Dogs II Flashcards

Question

You have just diagnosed your first case of nephrogenic diabetes insipidus, with a little help from the internist in your practice. The owner would like to discuss treatment options. **Which of the following is a treatment option for primary nephrogenic diabetes insipidus in a dog?** - Hydrochlorothiazide - Salting the food - DDAVP - Insulin

Answer 1

Answer: **Hydrochlorothiazide** Explanation The correct answer is hydrochlorothiazide. Hydrochlorothiazide is a thiazide diuretic that paradoxically reduces urine output in patients with diabetes insipidus. Hydrochlorothiazide and AVOIDING excess salt intake are palliative measures that reduce urine output by reducing plasma sodium concentration, which reduces stimulation to the thirst center and water intake. This leads to a reduction in extracellular fluid volume and a decreased glomerular filtration rate. DDAVP is a synthetic antidiuretic hormone (ADH) used for treating central diabetes insipidus. With nephrogenic diabetes insipidus, there is an adequate amount of ADH, but the ADH receptors in the kidneys do not function properly. Diabetes mellitus requires insulin because it causes elevated blood sugar levels. Nephrogenic diabetes is due to a problem in the kidneys, and is not treated with insulin.

Answer 2

Answer: **Spherule** Explanation The correct answer is spherule. The diagnostic stage of Coccidioides immitis is the spherule. This is a 20-200 micrometer round, double-walled structure containing many endospores. As a reminder, the broad-based budding yeast is Blastomyces. The small yeast with large capsule is Cryptococcus, and the branching fungal hypha is Aspergillus. The small intracellular yeast is Histoplasma.

Answer 3

Answer: **Extraocular polymyositis** Explanation The answer is extraocular polymyositis. Extraocular polymyositis is a condition seen primarily in young Goldens and they present with the signs above. It is kind of similar to masticatory muscle myositis in that it occurs due to an autoimmune reaction against muscle antigens. It is treated with prednisone +/- azathioprine. The condition can be differentiated from these other conditions because orbital neoplasia and retrobulbar abscesses are usually unilateral. Abscesses are usually accompanied by more systemic signs. Orbital neoplasia is usually more slowly progressive and seen in older animals. Lymphoma could present in a similar fashion but is less likely in such a young dog with no other signs.

Answer 4

Answer: **Pyridostigmine** Explanation The correct answer is pyridostigmine. The important thing to do in this case is to both read the question carefully and view the radiograph in concert with each other. This dog has signs and findings that are most consistent with myasthenia gravis and resultant megaesophagus. Accordingly, pyridostigmine, which is an acetylcholinesterase inhibitor (anticholinesterase), is the best answer choice. If you chose sucralfate because you saw the megaesophagus and thought the dog must have esophagitis, your thinking was accurate but you ignored the dog's clinical signs of weakness. If this dog had presented for regurgitation, that would have been a more appropriate course of action. Acquired myasthenia gravis can also be treated with systemic corticosteroids to decrease immune attack of acetylcholine receptors, but inhaled fluticasone would not do the trick. Enalapril and NSAIDs are not indicated in this patient. Annotations: Orange lines: Outline of the gas dilated esophagus Yellow circles: Areas of alveolar pattern consistent with aspiration pneumonia. Radiographs provided by Adrien Hespel, DVM, MS, DACVR and University of Tennessee College of Veterinary Medicine

Answer 5

Answer: **Xanthine** Explanation The correct answer is xanthine stones. Allopurinol is used in the treatment of urate stone forming Dalmatians. It acts by inhibiting the enzyme, xanthine oxidase, which metabolizes xanthine. The idea is that by stopping the purine metabolism pathway at this point, uric acid will not be formed in high quantities. However, if given at too high of a dose, xanthine will accumulate to levels where xanthine stones will form.

Answer 6

Answer: **The dog appears to be in proestrus** Explanation The timing of the dog's clinical presentation and vaginal cytology findings are most consistent with proestrus. Proestrus is characterized by <90% cornified cells. The cytology here is predominantly parabasal and intermediate cells; it is common for early proestrus to be characterized by these cells and gradually transition until nearly 100% of the cells are cornified by estrus. It is also common to see bloody vaginal discharge and very few or no red blood cells on the vaginal smear. ***PowerLecture: Estrous Cycle Part 1

Answer 7

Answer: **Give a dose of dexamethasone SP that is approximately 5 times the physiologic dose of prednisone before surgery followed by twice the regular dose of prednisone the following day** Explanation Patients with Addison's disease have hypoadrenocorticism. This means that the patient is not producing an adequate amount of glucocorticoids. During times of stress Addisonian patients require additional amounts of glucocorticoids or else they are at risk of going into a crisis. The exact amount of additional glucocorticoid to administer is not known but it is generally accepted that patients should receive 2-10 times a physiologic dose of prednisone. The physiologic dose of prednisone is considered by many to be 0.1 mg/kg/day but there is some variation depending on the source. Therefore the best answer is to give a dose of dexamethasone that is approximately 5 times the physiologic dose of prednisone followed by twice the regular dose of prednisone the following day. The patient is likely receiving deoxycorticosterone pivalate (Percorten) which is given at approximately 25-28 day intervals and is a means of providing the necessary mineralocorticoids. An alternative treatment for mineralocorticoid replacement is fludrocortisone acetate (Florinef). This medication needs to be administered daily. Weaning the patient off of prednisone is contraindicated and will result in an Addisonian crisis as the patient is unable to produce its own cortisol.

Answer 8

Answer: **Poor with surgical repair of the lesion** Explanation The correct answer is poor. The lack of deep pain with spinal cord trauma is a poor prognostic indicator, and even with surgical intervention at this point, there is less than a 5% chance of a return to function.

Answer 9

Answer: **Atoxalaner** Explanation From the list of medications Afoxalaner (Nexgard) is the best choice. This flea medication contains an adulticide; whereas, pyriproxyfen and Lufenuron are only insect growth regulators. Spinosad should never be used with extra-label doses of Ivermectin and is probably why this client discontinued flea medications in the first place. Permethin is an excellent flea medication, as it is a repellent and adulticide, but it is toxic to cats. Fipronil is toxic to rabbits. ***PowerPage: Flea Allergy Dermatitis

Answer 10

Answer: **Avascular necrosis of the femoral head. Perform femoral head and neck ostectomy or total hip replacement** Explanation Based on the breed and age of the patient, avascular necrosis of the femoral head should immediately be the top differential. This condition is also known as Legg-Calves-Perthes disease and results in a collapse or fragmentation of the femoral epiphysis (as seen on the radiographs) because of a disruption in blood flow. The cause of blood flow interruption is unknown. The condition occurs in young small-breed dogs prior to closure of the capital femoral physis. The condition can be seen bilaterally in 10-17% of patients. Dogs are usually 6-7 months of age when they first start showing clinical signs but the age may range from 3-13 months. Treatment with a femoral head and neck ostectomy (FHO) generally yields excellent results. Alternatively, if owners demand perfect biomechanics, a total hip replacement may be considered, but most veterinarians tend to recommend an FHO. Radiographs will typically show a shortening of the femoral neck as well as osteochondrosis with chronicity, as appreciated in this patient. Note the significant muscle atrophy of the patient's left limb as compared to the right. Patellar luxation should always be a differential in any small breed dog and this should be ruled out via palpation since the patient may not necessarily be luxated at the time the radiograph was taken. The patient's patellas are in a normal position in this radiograph. Septic arthritis of the femoral head is an uncommon condition which is more often seen in large-breed dogs with a history of degenerative joint disease of the hips. They present with acute lameness, severe hip pain, and are usually febrile. Radiographs usually show degenerative joint disease along with potentially lytic areas associated with the femoral head. Neoplasia should also be considered in these cases. Small-breed dogs are less likely to have hip dysplasia as compared to large-breed dogs and should be kept as a lower differential. Radiographs provided by Adrien Hespel, DVM, MS, DACVR and University of Tennessee College of Veterinary Medicine

Answer 11

Answer: **Dogs: Anemia / Humans: Cutaneous larval migrans** Explanation This is a case of hookworms (Ancylostoma caninum). The eggs are recognizable by their thin-walled appearance with 2-8 cells that are passed. Hookworms penetrate through the skin in young pups and migrate to the lungs where they are coughed up and swallowed and mature in the small intestine. There, the worms suck blood and cause bleeding ulcers; up to 0.1 ml of blood per worm can be lost per day. Aberrant migration under the skin of infected people results in cutaneous larva migrans. Visceral and ocular larva migrans in people are usually due to Toxocara (roundworms).

Answer 12

Answer: **Fanconi syndrome** Explanation The correct answer is Fanconi syndrome. Fanconi syndrome is an inherited disease in Basenjis. The disease involves renal tubular defects causing an abnormal loss of electrolytes and solutes leading to hypophosphatemia, hypokalemia, and metabolic acidosis. DM is less likely because serum glucose is normal. The lab abnormalities present in this dog are not consistent with pyelonephritis. Pyometra is not a viable choice as the signalment describes a male.

Answer 13

Answer: **Inherited glaucoma** Explanation The correct answer is inherited glaucoma. Cocker Spaniels are predisposed to developing eye problems such as cataracts, distichiasis, retinal abnormalities, and primary glaucoma. Even though only the left eye currently has increased intraocular pressures, the right eye should be treated as well because it will likely develop glaucoma in the future.

Answer 14

Answer: **Cholinesterase inhibitors** Explanation The correct answer is cholinesterase inhibitors. The dog has Myasthenia Gravis, which is caused by antibody-mediated destruction of acetylcholine receptors. Cholinesterase inhibitors decrease the break down of acetylcholine, making more acetylcholine available to bind to the remaining acetylcholine receptors. Myasthenia Gravis can be caused by immune mediated disease (related to hypothyroidism), paraneoplastic syndrome (associated with thymoma), and can be familial in certain breeds (Newfoundland and Great Dane).

Answer 15

Answer: **Leptospirosis** Explanation The correct answer is leptospirosis. Leptospirosis typically manifests as acute renal failure.

Answer 16

Answer: **Tell the owner the dog has a guarded to poor prognosis and may need hemodialysis** Explanation The correct answer is tell the owner the dog has a guarded to poor prognosis and may need hemodialysis. 4-MP and ethanol act by preventing alcohol dehydrogenase from converting ethylene glycol to its toxic metabolites. In animals where oliguric renal failure has already begun, most of the ethylene glycol will already have been metabolized, so there is no benefit to giving ethanol or 4-MP. Activated charcoal should only be given if the ethylene glycol was ingested within 2 hours. ***PowerPage: Toxins in the Garage (ethylene glycol, household cleaners)

Answer 17

Answer: **He has a post-ganglionic lesion** Explanation The answer is that he has a post-ganglionic lesion. Hydroxyamphetamine acts by encouraging release of norepinephrine (NE) from the postsynaptic neuron. If there is a pre-ganglionic lesion, NE will still be released by the postsynaptic neuron and signs will resolve. If there is a post-ganglionic lesion, there will be no NE to release. Also, with a post-ganglionic lesion, denervation hypersensitivity to NE occurs. As a result, adding phenylephrine topically can cause a rapid response. With pre-ganglionic lesions, the response usually takes greater than 20 minutes.

Answer 18

Answer: **Malassezia infection** Explanation Malassezia infection of the claws often produces a red-brown discoloration. Other clues that this is more likely Malassezia include biting at the nails (sign of pruritus), multiple claws are infected, and the dog has other symptoms of allergy (pruritus in summer months), which could be this patient's underlying disease. Trauma and neoplasia are less likely since multiple claws are infected, and these typically are not pruritic unless there is a secondary bacterial component. Symmetrical lupoid onychodystrophy results in severe splitting and deformation of the nails. Sarcoptes does not discolor the nails.

Answer 19

Answer: **Continue to monitor carefully without disturbing her and have the dog return in 24 hours if she has not delivered the puppies** Explanation Based on the history and clinical examination findings, this dog has presented in stage 1 of labor. This stage is typically 6-12 hours of length and can persist for up to 36 hours. In this stage, it is expected for the dog to exhibit panting, trembling, nesting behavior, and restlessness. Occasionally dogs will also vomit. At this point, there is sub-clinical uterine contraction and dilation of the cervix. Stage 2 will also last approximately 6-12 hours (and persist up to 36hr) and is characterized by abdominal straining which coincides with uterine contraction. Puppy delivery occurs during Stage 2 at an interval of 30-60min (up to 4 hours). Stage 3 involves the expulsion of fetal membranes as well as involution of the uterus. Fetal membranes are usually passed 5-15 minutes after birth of a pup before another puppy can be delivered from the same horn. Thick greenish discharge (lochia) is seen in all stages of labor and may persist for up to three weeks. Complete uterine involution and endometrial recovery occurs in approximately 3 months.

Answer 20

Answer: **Ventrodorsal** Explanation The correct answer is ventrodorsal. Pleural effusion obscures the heart completely on a dorsoventral radiograph and at least partially on lateral radiographs. Ventrodorsal positioning usually moves the pleural fluid away from the heart and allows for a radiographic view of the heart to be obtained. Of course, in dyspneic animals, it may not be wise to position them ventrodorsally.

Answer 21

Answer: **Neorickettsia helminthoeca** Explanation The correct answer is Neorickettsia helminthoeca. This dog most likely has salmon poisoning disease. The etiologic agent of the disease is the rickettsia, Neorickettsia helminthoeca, which is vectored by the intestinal fluke, Nanophyetus salmincola. Dogs get the disease by eating salmonid fish infected with the cercaria of the fluke, which harbor the rickettsia. Clinical signs along with finding fluke eggs in the feces of the dog is usually enough to make the diagnosis. Paragonimus kellicotti is a lung fluke of the dog.

Answer 22

Answer: **Dexamethasone** Explanation The correct answer is dexamethasone. Administration of dexamethasone or desoxycorticosterone acetate (DOCA) prior to ACTH stimulation test does not confound the test results. Administration of prednisone, cortisone, prednisolone, and flucortisone acetate would show false elevations in test results.

Answer 23

Answer: **Degenerative myelopathy** Explanation According to this patient's clinical signs there is a lesion from T3-L3, evidenced by the upper motor neuron signs in the hind limbs and no clinical signs in the front limbs. Because of the progressive nature of the disease, you can rule out a fibrocartilaginous embolism. Hip dysplasia can be difficult to differentiate from degenerative myelopathy in some patients, but the reflexes should not be affected with degenerative joint disease. Lyme disease would likely be acutely painful and/or recurrent in nature.

Answer 24

Answer: **ACTH low, cortisol high** Explanation The correct answer is ACTH low, cortisol high. Prednisone is a synthetic corticosteroid that cross reacts with assays measuring endogenous cortisol levels, causing an artificially elevated cortisol measurement on blood tests. The feedback mechanism on the pituitary gland inhibits ACTH production, making it low.

Answer 25

Answer: **Struvita** Explanation The correct answer is struvite. Struvite or magnesium ammonium phosphate crystals form in alkaline urine, whereas most other crystal types form in acidic urine. The cocci present are urease positive bacteria that cleave urea to ammonia causing the urine pH to rise and making the environment more favorable for struvite crystals to form. Cysteine crystals form as a result of a genetic defect of the renal tubules, and are almost exclusively seen only in males. Urate crystals only form in Dalmatians (due to a genetic defect in urate metabolism) and animals with portosystemic shunts or liver dysfunction. Urates are less likely in this patient, since it is not a Dalmatian and shows no signs of liver disease.

Answer 26

Answer: **Direct fluorescent antibody test** Explanation The correct answer is direct fluorescent antibody test. There are no gross pathologic lesions associated with rabies. A diagnostic microscopic lesion is the visualization of Negri bodies. Most commonly they occur in the hippocampus in carnivores and Purkinje cells in herbivores. However, these are only seen 50% of the time. Immunohistochemistry allows strain differentiation and the ability to differentiate vaccine vs. wild-type. RT-PCR has been used on autolyzed brain tissue that is difficult to evaluate with fluorescent antibodies, but this is not the test of choice at this time. Direct FA is the current preferred method of diagnosis; it is both rapid and sensitive. Usually impressions of the medulla, cerebellum, and hippocampus are performed.

Answer 27

Answer: **Phenylpropanolamine** Explanation The correct answer is phenylpropanolamine. This medication increases urethral sphincter tone and helps prevent incontinence. Diethylstilbesterol and testosterone have been used for incontinence, but both are hormones. Propranolol is a beta blocker used for certain types of heart disease.

Answer 28

Answer: **Phenylpropanolamine** Explanation The correct answer is phenylpropanolamine. This medication increases urethral sphincter tone and helps prevent incontinence. Diethylstilbesterol and testosterone have been used for incontinence, but both are hormones. Propranolol is a beta blocker used for certain types of heart disease.

Answer 29

Answer: **Typell external fixator** Explanation The correct answer is Type Il external fixator. A type I external fixator can be placed from the lateral aspect of the femur, but the medial aspect of the femur can not be approached for a type ll external fixator due to the bone being directly adjacent to the trunk of the animal.

Answer 30

Answer: **Topical mannitol** Explanation The answer is topical mannitol. Carbonic anhydrase inhibitors act by decreasing aqueous production which is partially dependent on the conversion of carbon dioxide to bicarbonate. It can be used topically or systemically. Latanoprost (Xalatan) is a prostaglandin analog frequently used topically in the treatment of glaucoma. IV mannitol works to decrease IOP through its properties as an osmotic attractant. It is not used topically.

Answer 31

Answer: **T3-L3 myelopathy** Explanation This signalment and clinical signs are consistent with interverebral disc disease (disc herniation). Dachshunds are the most common breed to develop IVDD. The clinical signs described in this case are not complete but do give you enough information to determine that upper motor neuron signs are present (hyper-reflexive). This immediately eliminates the possibility of having a caudal spinal cord injury as those result in lower motor neuron signs (hypo-reflexia). Deficits of the forelimbs are usually associated with neck lesions. A Schiff-Sherington posture is one exception in which the forelimbs are affected but the lesion is not in the neck. Although it is very common for lesions to be between T11-13 such a specific location is not defined by the neurologic exam findings provided. The neurological exam description is not very specific and the localization is T3-L3.

Answer 32

Answer: **Depigmentation of the nasal planum** Explanation The correct answer is depigmentation of the nasal planum. Clinical signs consistent with DLE include depigmentation, erythema, scaling, and loss of the "cobblestone" appearance of the nasal planum. Alopecia, crusting, scaling, and ulcerations can also be seen on the face, muzzle, lips, pinnae, and periorbitally. Truncal alopecia would be more common with endocrine disease, such as hypothyroidism or Cushing's disease. Discoid lupus is the cutaneous form, and the joints are not affected like they are with systemic lupus erythematosus (SLE).

Answer 33

Answer: **Depigmentation of the nasal planum** Explanation The correct answer is depigmentation of the nasal planum. Clinical signs consistent with DLE include depigmentation, erythema, scaling, and loss of the "cobblestone" appearance of the nasal planum. Alopecia, crusting, scaling, and ulcerations can also be seen on the face, muzzle, lips, pinnae, and periorbitally. Truncal alopecia would be more common with endocrine disease, such as hypothyroidism or Cushing's disease. Discoid lupus is the cutaneous form, and the joints are not affected like they are with systemic lupus erythematosus (SLE).

Answer 34

Answer: **Chorioretinitis** Explanation Chorioretinitis (posterior retinitis) refers to inflammation of the choroid and retina. Signs of ongoing or acute chorioretinitis in dogs are poorly defined gray spots throughout the fundus, retinal separation, and retinal hemorrhage. Active disease, such as in this dog, is typically caused by systemic disease. Full labwork and infectious disease testing should be submitted. The list of potential causes for chorioretinitis is fairly long: Parasites Fungal infections Bacterial infection (e.g., Rickettsia) Viral infections (e.g., canine distemper virus, rabies virus, and herpes virus, which is rare and usually seen in newborn puppies) Algal infections (water plant-based infection, typically from plants growing in stagnant water) Protozoal infection Autoimmune disease Genetic predisposition Metabolic Cancer Generalized infection, such as blood poisoning or bacteria in the blood Toxicity (e.g., antifreeze poisoning, or adverse reaction to medications) Physical trauma Idiopathic Chorioretinitis can lead to glaucoma as a complication, but this dog has below normal intraocular pressures at this time (suggestive of inflammation in the anterior portion of the eye). Optic nerve hypoplasia is a genetic condition where the optic nerve never fully develops and causes vision loss or blindness. This dog's tear test is normal, ruling out KCS.

Answer 35

Answer: **HOD can be extremely painful, causing lameness in dogs** Explanation The correct answer is HOD can be extremely painful, causing lameness in dogs. HOD usually occurs in young, large breed dogs. It can recur after an episode resolves, and treatment usually involves analgesia and supportive care. Surgery is not a treatment option. Radiographically, this condition appears as a line of lucency where the bone has been destroyed, typically parallel to the growth plates of the affected bones. This is sometimes referred to as a "double physis" sign.

Answer 36

Answer: **Desmopressin acetate** Explanation The correct answer is desmopressin acetate (DDAVP). Administration of desmopressin results in release of von Willebrand factor, which will help this patient with clotting. Given this dog's breed and elevated BMBT there is a very strong likelihood she is afflicted with von Willebrand's disease. In Dobermans this results in an inability to form a clot. This can be life threatening if the dog is taken to surgery. A whole blood transfusion does not provide an adequate source of von Willebrand factor but may be necessary if the patient's bleeding cannot be controlled despite appropriate pre-operative measures. 1,25 dihydrocholecalciferol is the active form of vitamin D which aids intestinal resorption of calcium. The BMBT does not assess factors 2, 7, 9, or 10 and therefore vitamin K is not indicated.

Answer 37

Answer: **Actinomyces** Explanation The correct answer is Actinomyces. This is a filamentous, branching, gram positive bacteria that is a normal inhabitant of the mouth and oropharynx. It is commonly associated with grass awn migration. These are usually contaminated in the oropharynx and then migrate through the body from the respiratory or GI tracts. Many times it takes months to years to make a diagnosis. Nocardia is a ubiquitous soil saprophyte found everywhere and is usually introduced via the respiratory tract.

Answer 38

Answer: **Sporotrichosis** Explanation The correct answer is Sporotrichosis. All of these fungal diseases can infect both animals and people. However, they are not considered contagious (not to be confused with infectious) with the exception of Sporothrix. This is because they are mainly acquired from the environment, and transmission from animal to animal is rare. Sporothrix, especially in cats, is a high risk to veterinarians and care should be taken to limit contact with exudates and lesions in cats. Aspergillus is generally considered a ubiquitous fungus that causes infection due to host factors such as immunosucceptibility or certain breed predilections. Cryptococcus is also not a contagious disease (do NOT confuse this with cryptosporidium, which is very contagious and zoonotic as several of my colleagues can attest to profusely). Cryptococcus infection occurs from inhalation of the yeast from the environment, frequently avian habitats, as it survives ideally in pigeon droppings. Essentially, histoplasma, blastomyces, and Coccidioides are also all environmental diseases as well and not considered contagious. Incidentally, there is a true story of a pathologist who did acquire Coccidioides from an animal that was having a necropsy. It is likely that the fungus reverted to the mycelial phase and produced infectious arthroconidia at the low temperatures achieved in the dead animal. This is also a risk when changing bandages for the same reason. These fungi are also potentially infectious when they are being grown on culture plates. So even though they are not technically contagious (at least in terms of how the board examiners view them), there are still risks.

Answer 39

Answer: **800 kcal/day** Explanation The correct answer is 800 kcal/day. There are many formulas for calculating RER and they all should work out to be pretty close to this. The formula used here is body weight (kg) to the 0.75 power times 70. (70 * BW^0.75). Another formula that has been recommended for this calculation is (30 * BW + 70). Note that the results will be different compared to the (70 * BW^0.75) formula but they both should get you close enough to the correct answer. You will have access to an "on screen" calculator during the exam if necessary, but may want to remember multiple ways to do a calculation should there not be access to a "power" (^) function.

Answer 40

Answer: **Amitraz (Mitaban)** Explanation The correct answer is amitraz (Mitaban). This is a case of generalized demodicosis which can occur in older dogs as well as young dogs. It is caused by the commensal mite, Demodex canis, and is often secondary to an underlying disease or immunosuppression. There are several treatment options (and you should probably know them all) but the only FDA-approved treatment is Amitraz (Mitaban). Ivermectin and milbemycin are also used to treat this condition in part because it is difficult to obtain Mitaban. Mitaban is used as dip and should be administered in a hospital, which is time consuming when there are other treatment options that can be similarly effective although used "off-label". Mitaban should be used cautiously in animals with skin lesions since more systemic absorption of Mitaban will occur which increases the likelihood of toxic affects.

Answer 41

Answer: **Low carbohydrate and fat, high protein diet** Explanation The answer is low carbohydrate and fat, high protein diet. Animals with hepatic encephalopathy require protein reduction in their diets. Lactulose is given because it decreases colonic pH, trapping ammonia, and decreases transit time through the gut, leading to decreased ammonia uptake because ammonia contributes to hepatic encephalopathy. Oral neomycin is used to dampen urease-producing microflora of the gut and consequently, decrease ammonia production in the gut. It has also been shown that vegetable and dairy proteins are better tolerated than meat proteins. On the radiograph, note the liver tucked well under the rib cage and the corresponding cranial shift of the gastric axis consistent with microhepatica.

Answer 42

Answer: **Toceranib phosphate (Palladia)** Explanation In 2009, toceranib (Palladia) became the first FDA-approved veterinary chemotherapeutic for treatment of cancer. Toceranib is an inhibitor of a membrane-bound signaling molecule called a receptor tyrosine kinase (RTK). Many mast cell tumors are known to have mutations in an RTK that contributes to their aggressive behavior and can be blocked by this drug. Previously, all chemotherapeutics were human-approved drugs used off-label, and this is the case for the other choices listed. Because the approval of this drug was the first of its kind, it has the potential to show up on boards.

Answer 43

Answer: **Butorphanol and theophylline** Explanation The radiographs show dynamic collapse of the intrathoracic trachea, carina, and mainstem bronchi. There is a marked redundant tracheal membrane in the cervical region. The left atrium may be slightly enlarged but there is no evidence of left heart failure. Based on these findings, you should suspect that tracheal collapse is the cause of the dog's clinical signs. Treatment options include bronchodilators (i.e. theophylline, terbutaline), cough suppressants (hydrocodone, butorphanol), weight loss, and corticosteroids to control inflammation. In severely affected dogs, sedation may be necessary to break the cough cycle. Dogs should be kept away from smoke and environmental pollution. About 70% of dogs respond to medical management. Those that don't are sometimes treated with stents or tracheal rings, but neither repairs the underlying cartilaginous defect. Furosemide is not an appropriate treatment as there is no evidence of heart failure. Nebulization and coupage are used to treat pneumonia, which is also not present in this case. Annotations: Red is the tracheal diameter, much more narrowed on the Right lat Green is a redundant tracheal membrane visible on the left lateral Yellow are primary bronchi for the right cranial lung lobe (left lateral), and cranial subsegment of the left cranial lung lobe (right lateral). Notice the large difference in diameter. Tracheomalacia, bronchomalacia and redundant tracheal membrane. Blue: there is significant narrowing of the tracheal bifurcation on the right lateral compared to left. Indicative of dynamic airway collapse. Radiographs provided by Adrien Hespel, DVM, MS, DACVR and University of Tennessee College of Veterinary Medicine

Answer 44

Answer: **Tetracycline antibiotics** Explanation The correct answer is tetracycline antibiotics. The causative agent for the dog's clinical signs is Neorickettsia helminthoeca. Treatment of choice for this rickettsial agent is tetracycline antibiotics. The fluke itself is not responsible for the clinical signs, but may be treated effectively with Praziquantel.

Answer 45

Answer: **Chlorhexidine** Explanation The key here is to recognize that the question is asking about peripheral vestibular disease; otherwise, metronidazole would be a good choice as a cause of central vestibular disease. Chlorheadine is a topical drug implicated in ototoxicity and peripheral vestibular disease. Another excellent choice would be aminoglycosides including neomycin, kanamycin, tobramycin, amikacin and gentamicin.

Answer 46

Answer: **Serum cholesterol** Explanation The correct answer is serum cholesterol. Cholesterol is elevated in up to 90% of hyperadrenocorticism cases. BUN is usually low in patients with hyperadrenocorticism secondary to the increased diuresis that occurs with elevated cortisol levels. ALT increases due to swelling and death of some hepatocutes. SAP increases due to a steroid-induced isoenzyme of SAP from the liver. Mild cholestasis due to swelling of hepatocytes also contributes to a minor part of the increase in SAP. T4 is often low in patients with Cushinga?? because they are euthyroid sick. Potassium is usually elevated with hypoadrenocorticism (not hyperadrenocorticism).

Answer 47

Answer: **Desmopressin acetate** Explanation The correct answer is desmopressin acetate (DDAVP). Administration of desmopressin results in release of von Willebrand factor, which will help this patient with clotting. Given this dog's breed and elevated BMBT there is a very strong likelihood she is afflicted with von Willebrand's disease. In Dobermans this results in an inability to form a clot. This can be life threatening if the dog is taken to surgery. A whole blood transfusion does not provide an adequate source of von Willebrand factor but may be necessary if the patient's bleeding cannot be controlled despite appropriate pre-operative measures. 1,25 dihydrocholecalciferol is the active form of vitamin D which aids intestinal resorption of calcium. The BMBT does not assess factors 2, 7, 9, or 10 and therefore vitamin K is not indicated.

Answer 48

Answer: **CN VII** Explanation The correct answer is CN VII. This is the facial nerve which is responsible for motor of the facial muscles as well as sensation in the ear and lacrimation. CN V is mostly responsible for sensation. CN Ill is the oculomotor nerve and serves in movement of the eye. CN VI is also involved in movement of the eye.

Answer 49

Answer: **Skin scrape** Explanation Demodex injai typically causes greasy seborrhea, especially on the face and dorsal trunk. Terriers and Shih Tzus may be predisposed. Some dogs may be pruritic. This mite is long and slender when compared with Demodex canis. A diet trial and intradermal skin test may be indicated in the future if the skin scrape is negative. A bacterial culture may be needed if bacteria were seen on cytology. There is no indication to perform a CBC. None of the other tests would be considered part of a dermatological database.

Answer 50

Answer: **Staphylococcus** Explanation Bacteria may be a cause of folliculitis. Pustules such as this are commonly associated with Staphylococcus. Dermatophytes, and most species of Demodex, can also infect the hair follicle. Sarcoptes scabiei, which is a non-seasonal, intensely pruritic, transmissible mite, affects the stratum corneum and is less likely to cause a folliculitis. Chyletiella mites feed on the keratin layer of the skin as well and are less likely to cause folliculitis. These mites are known as "walking dandruff" and may cause skin flaking and typically intense pruritis. Trichodectes is a chewing louse, which chews the skin but does not involve the hair follicle.

Answer 51

Answer: **Hyposensitization injections based on intradermal skin test results** Explanation Based on the signalment, history, and physical exam findings, you should be most suspicious of atopic dermatitis (atopy). Atopy can occur in any aged dog but typically begins in dogs between 1.0 and 3 years of age. It frequently can be seasonal, in contrast to food allergy. Ultimately, atopy is frequently a diagnosis of exclusion made by ruling out flea and food allergy with measures such as strict flea control and an elimination diet. However, enough clues are given here, and the question specifically asks for the treatment for the most likely underlying etiology. Fipronil (Frontline) and S-methoprene are flea insecticidal therapies. The distribution of the lesions makes flea allergy less likely, and additional flea insecticides unwarranted. Cephalexin and chlorheadine shampoos are treatments for pyoderma; pyoderma can occur secondary to any allergic skin disease but is not the likely underlying etiology in this case. ***PowerPage: Allergic Skin Disease

Answer 52

Answer: **Staphylococcus pseudintermedius (Staphylococcus intermedius)** Explanation Intracytoplasmic cocci from a dog's skin are most likely Staphylococcus pseudintermedius (formerly called Staphylococcus intermedius), which is the species host-adapted to canines. Staphylococcus hyicus is host-adapted to pigs, so is less likely to be isolated from a dog. Malassezia (yeast) organisms are much larger than cocci and are not observed within the cytoplasm of neutrophils.

Answer 53

Answer: **Careful hygiene should be instituted after playing with the animal, but the risk of humans developing this infection is low** Explanation Good hygiene practice such as hand washing should be performed after contact with the animal. There is a low risk of transfer of Staphylococcus pseudintermedius from animals to humans since this staphylococcus is host-adapted to dogs. The risk is higher for immunocompromised humans and humans with open wounds. Euthanasia is unnecessary, since this is a curable disease and the risk to humans is low. Quarantine is generally not indicated. If these bacteria had been Staphylococcus aureus, the risk to humans would be much greater. Most dogs do not culture Staphylococcus aureus, since it is host-adapted to humans. Additionally, it is believed that most cases of Staphylococcus aureus in dogs are a result of transfer from their owners. Quarantine may be necessary for select cases of Staphylococcus aureus in dogs if their owner is immunocompromised.

Answer 54

Answer: **Mast cell tumor** Explanation The correct answer is mast cell tumor. Mast cells contain granules with inflammatory mediators including heparin and histamine and commonly cause local inflammation. They can also cause paraneoplastic signs associated with hyperhistaminemia and hyperheparinemia. Half of mammary tumors in dogs are benign and half are malignant. Even the malignant ones do not usually have associated inflammation with the noteworthy exception of a relatively rare type of tumor called an inflammatory mammary carcinoma that carries a very poor prognosis. Hemangiosarcoma and lymphoma are both malignant tumors but are not usually associated with extensive inflammation. Cutaneous melanoma in the dog is benign in 80-90% of cases in contrast to humans. ***PowerPage: Mast Cell Tumors

Answer 55

Answer: **Fine needle aspiration of the mass and abdominal ultrasound** Explanation A mass in the 4 o'clock or 8 o'clock regions is most consistent with an anal sac tumor, which are most commonly apocrine gland adenocarcinomas; however, a fine needle aspirate or biopsy is needed for a definitive diagnosis. Hypercalcemia is occasionally associated with this tumor type and dogs commonly present for tenesmus or licking around the perianal region. The sublumbar lymph nodes are the most common site for metastasis so abdominal ultrasound prior to excision of the mass is recommended to determine the extent of the disease. Depending on the size of the mass, surgical removal should be recommended along with surgical removal of the sublumbar lymph nodes if they are enlarged. Radiation therapy of the anal sac region along with the lymph nodes (if not excised) may also be recommended to slow or prevent tumor recurrence. Chemotherapy has been used in conjunction with other therapies but results are variable.

Answer 56

Answer: **Regular** Explanation Listed from shortest acting and most potent to longest acting and least potent: Regular, NPH, Lente, PZI, Ultralente. The treatment of DKA involves IV fluids and regular insulin, given either by CRI or the intermittent IM dosing technique. Regular insulin is continued until the patient is eating well and is hydrated, and can be switched to a longer-acting insulin, to be given SQ at home.

Answer 57

Answer: **Triglyceride concentration of the fluid compared to serum** Explanation The correct answer is triglyceride concentration of the fluid compared to serum. The fluid described is most consistent with a chylous effusion. The best way to definitively classify chyle is finding an elevated triglyceride level compared to serum. If you chose differential cell count, this is also a good answer because most chylous effusions are composed primarily of lymphocytes, unlike other effusions. However, with prolonged loss of lymphocytes, chronic chylous effusions may be composed primarily of neutrophils, which may lead you to believe it is an exudate. Radiographs and culture and sensitivity may be appropriate tests but will not help you classify the fluid. Glucose concentration of the fluid is not useful in this instance. It is sometimes used to diagnose pyothorax as glucose concentrations are typically < 10 mg/dl.

Answer 58

Answer: **Observation without treatment** Explanation The correct answer is observation without treatment. Most cases of canine oral papillomatosis will resolve without treatment in about 3 months. In severe cases, treatment might include surgical removal, laser ablation, or cryotherapy. Although, papillomatosis is usually benign, transformation to squamous cell carcinoma can occur but this is very rare. Canine oral papillomatosis is very common and affects young dogs. It is caused by papillomavirus, which spreads by direct and indirect contact. Usually infection occurs at sites of damaged skin or mucous membranes.

Answer 59

Answer: **Pancreatic acinar atrophy** Explanation The correct answer is pancreatic acinar atrophy. This is an idiopathic condition where the exocrine cells of the pancreas atrophy with minimal inflammation. Chronic pancreatitis is a much more common cause of EPI in cats than dogs. For this reason, dogs with EPI do not usually have concurrent diabetes mellitus because the endocrine cells are spared, whereas cats often do have concurrent DM. Neoplasia and infection are rare causes of EPI. ***PowerPage: Pancreatitis and Exocrine Pancreatic Insufficiency ***PowerLecture: Pancreatitis

Answer 60

Answer: **Morphine and thiopental** Explanation In this case, thiopental is contraindicated because the patient is a sighthound. Thiopental is an ultrashort acting barbiturate. Recovery depends on redistribution to tissues, including fat. Because sighthounds have very little fat, they have prolonged recoveries and greater complications with these drugs. Morphine is contraindicated in this patient due to the ulcerating mast cell tumor. Morphine can cause histamine release and should be avoided in mast cell tumor patients. ***PowerLecture: Opiates

Answer 61

Answer: **Supraventricular tachycardias may progress to atrial fibrillation and cause progressive left ventricular dysfunction, whereas ventricular tachycardias may lead to ventricular fibrillation and death.** Explanation Supraventricular tachycardia can lead to atrial fibrillation, which is not life threatening. With atrial fibrillation, the atrial depolarization rate in a dog is usually from 400-700/minute. Usually, about one third of depolarizations get through the AV node to the ventricles to cause a ventricular contraction. Rapid supraventricular arrhythmias can wear out the LV myocardium causing LV dysfunction. Ventricular tachycardias, however, can cause electrical instability and progress to ventricular fibrillation, which leads to cardiovascular collapse and death if not rapidly converted back to a normal rhythm.

Answer 62

Answer: **Total solids of 6.0** Explanation HGE is characterized by acute onset of hemorrhagic diarrhea accompanied by marked hemoconcentration. HGE can be due to a hypersensitivity reaction in the intestines or from Clostridium perfringens enterotoxin. It usually affects small dogs such as Miniature Poodles and Miniature Schnauzers. They develop a raspberry jam-like diarrhea, vomiting, and abdominal pain. The key findings are a high PCV of 55-60 and normal total protein that is not as high as would be expected from the degree of hemoconcentration, probably due to protein loss into the intestine

Answer 63

Answer: **Carbonic anhydrase inhibitor** Explanation Carbonic anhydrase inhibitors (such as dorzolamide) act by decreasing aqueous production, which is partially dependent on the conversion of carbon dioxide to bicarbonate. It can be used topically or systemically. Latanoprost (Xalatan) is a prostaglandin analog frequently used topically in the treatment of glaucoma. IV mannitol works to decrease IOP through its properties as an osmotic attractant; it is not used topically. Atropine is contraindicated in some glaucoma cases. Tacrolimus is used as a topical immunosuppressant, and used most commonly for dry-eye.

Answer 64

Answer: **Iron deficiency** Explanation The correct answer is iron deficiency. The CBC shows a microcytic, hypochromic, non-regenerative anemia. Reticulocyte counts under 60,000/ul are typically considered non-regenerative in most labs. This is consistent with chronic iron deficiency. This most common reason for chronic blood loss is gastrointestinal tract disease such as an ulcer or cancerous lesion.

Answer 65

Answer: **Tetanus antitoxin can cause anaphylaxis.** Explanation The facial contraction and smirk is a characteristic sign of tetanus. Tetanus is caused by the neurotoxin produced by Clostridium tetani. This bacteria enters the body through a wound and begins producing tetanospasmin, a potent neurotoxin that blocks GABA release at the motor end plate and causes sustained muscle contraction. Treatment involves wound debridement, sedation, antibiotics, and minimizing external stimuli as these animals are hyperesthetic. Tetanus antitoxin is given after an initial test dose to monitor for anaphylaxis. Antitoxin prevents further toxin binding but does not affect already bound toxin so it helps decrease progression of clinical signs but will not reverse the signs present. Tick paralysis starts with hind limb weakness which progresses to a stiff forelimb gait and flaccid paralysis. Patients will improve quickly after removal of the tick. Clostridium botulinum causes botulism which is characterized by lower motor neuron paresis/paralysis starting in the pelvic limbs and progressing to quadriplegia. There is decreased muscle tone in all limbs.

Answer 66

Answer: **High-dose dexamethasone suppression test** Explanation The correct answer is high-dose dexamethasone suppression test. HDDST will suppress cortisol secretion in about 75% of PDH patients 3-6 hours post dexamethasone administration. Cortisol secretion does not become suppressed with dexamethasone administration with adrenal dependent hyperadrenocorticism. If cortisol secretion is suppressed with a HDDST, PDH is diagnosed. If cortisol is not suppressed, there is a 50-50 chance that the hyperadrenocorticism is due to PDH or an adrenal tumor. LDDST will suppress cortisol secretion in approximately 65% of pituitary dependent hyperadrenocorticism patients. The urine cortisol:creatinine ratio measures the significance of urine cortisol concentration and may be increased with both PDH and ADH. Serum cortisol levels may be affected in many different situations such as stress; therefore they are an unreliable indicator of disease. An elevated serum cortisol level will not differentiate between PDH and ADH.

Answer 67

Answer: **Chronic lymphocytic leukemia** Explanation 'Chronic' describes the clinical course of the disease, which is considered indolent or slowly progressive. The neoplastic cells of chronic leukemias are well differentiated or mature cells; therefore, CLL is considered a chronic or indolent form of leukemia made up of small, mature lymphocytes. These are difficult to distinguish from normal lymphocytes. The mildly prominent lymph nodes and prominent spleen are classic findings for chronic leukemias. The large disease burden within the bone marrow and relatively less affected lymphoid tissues (relative to lymphoma) makes this a lymphocytic leukemia as opposed to a small cell or low grade lymphoma.

Answer 68

Answer: **Cricopharyngeal dysphagia** Explanation The correct answer is cricopharyngeal dysphagia. This is a congenital disorder characterized by in-coordination of the swallowing reflex leading to the signs described. Megaesophagus could also cause regurgitation but should not cause the repeated swallowing and would probably be identifiable on radiographs in most cases. Pancreatitis often causes vomiting in dogs but not usually regurgitation unless there is secondary esophagitis. Ascarid infection also could cause vomiting if sufficiently severe.

Answer 69

Answer: **Familiarize yourself with your state's laws concerning the reporting of animal abuse and then determine the next steps.** Explanation Laws and procedures vary by state for mandatory reporting, You should review the laws in your state to ensure you are complying.

Answer 70

Answer: **Your dog likely has osteochondrits dissecans of the medial trochlear ridge and removal of the flap and curettage is recommended.** Explanation The radiographs show evidence of effusion when compared to the contralateral limb. There is also a widened joint space of on the medial aspect at the level of the tibio-tarsal joint with flattening of the medial trochlear ridge. Those specific findings are highly suggestive of osteochondritis dissecans (OCD). The signalment of the patient also fits with this diagnosis. Young dogs are not typically affected by fragmentation of the medial trochlear ridge. If you selected this answer you are probably confusing yourself with a fragmented medial coronoid process which is a component of elbow dysplasia. A joint infection of six weeks duration is highly unlikely and we would expect the dog to be more clinical if it was present for that length of time. Lethargy, inappetance, and pyrexia would be expected. The radiographic findings would probably show severe degenerative changes if it were ongoing for six weeks. A ligamentous injury cannot be ruled out on this radiograph alone. Stress radiographs would be necessary to see if there is excessive laxity of the joint. If the findings consistent with OCD were not present, offering the owners stress radiographs as the next step would be reasonable.

Answer 71

Answer: **Microsporum canis (cats); Microsporum gypseum (soil), Trichophyton mentagrophytes (rodents)** Explanation Microsporum gypseum is geophilic (meaning that it loves to grow in soil). This species often affects dogs that like to dig. Trichophyton mentagrophytes is zoophilic and usually rodents serve as the host; dogs such as hunting dogs or roaming cats are most commonly affected. Microsporum canis is most commonly contracted from cats. It is extremely important to know which species of dermatophyte is causing the infection in order to prevent re-exposure. For example, in dogs with Microsporum gypseum, preventing them digging in the yard is going to be an important part of the treatment plan.

Answer 72

Answer: **Piroxicam and carboplatin chemotherapy** Explanation Transitional cell carcinoma of the bladder in dogs can be palliatively managed with non-steroidal anti-inflammatory drugs such as piroxicam. Progression-free interval and survival can be extended with the addition of chemotherapy. The most commonly used agents are carboplatin, cisplatin, and mitoxantrone. Although cisplatin is effective against TCC, it has increased nephrotoxicity with piroxicam and is less commonly used these days in the author's experience. Secondary infections can be treated with appropriate antibiotics.

Answer 73

Answer: **It will probably also develop glaucoma in 6-12 months** Explanation The correct answer is that it will probably also develop glaucoma in 6-12 months. The usual course for primary glaucoma is development in one eye with the contralateral eye following in 6-12 months. These animals have an iridocorneal angle that becomes increasingly compromised during the first few years of life and eventually causes an acute pressure spike in the eye.

Answer 74

Answer: **Central diabetes insipidus** Explanation The correct answer is central diabetes insipidus. Males with Sertoli cell tumors may develop bilateral alopecia with occasional pruritus and papular eruptions. Hypothyroid dogs often develop alopecia, seborrhea, and pyoderma. Hyperadrenocorticism patients commonly develop hyperpigmentation, alopecia, calcinosis cutis, seborrhea, and pyoderma.

Answer 75

Answer: **Diestrus** Explanation The correct answer is diestrus. In diestrus, progesterone is the predominant hormone, and it promotes endometrial growth, suppresses myometrial activity, and inhibits leukocyte response to infection. This all predisposes the dog to development of pyometra.

Answer 76

Answer: **Blastomycosis** Explanation The correct answer is blastomycosis. Finding a broad-based budding organism is specific to blastomycosis. This dog is likely to have a travel history to the Ohio River valley. Being on chronic steroids resulted in immunosuppression and acquiring subsequent infection.

Answer 77

Answer: **Fluoxetine** Explanation Fluoxetine (Prozac) is an anti-depressant and SSRI that can be used to treat cats for anxiety related disorders at a dose of 0.5 mg/kg orally once daily. The other drugs listed are also antidepressants but are not SSRIs. Clorazepate (Tranxene) and alprazolam (Xanax) are benzodiazepine derivatives. Clomipramine and amitriptyline are tricyclic antidepressants. These drugs act, in part, by inhibiting serotonin-norepinephrine re-uptake but they are not selective serotonin re-uptake inhibitors.

Answer 78

Answer: **Treat with frequent doses or a constant rate infusion (CRI) of regular insulin initially to get the cat under glycemic control** Explanation The correct answer is to treat with frequent doses or a CRI of regular insulin initially to get the cat under glycemic control. Animals in DKA should be rehydrated with IV fluids and aggressively treated with frequent doses (or a CRI) of short-acting insulin (regular insulin) to obtain glycemic control before making any alterations to its normal insulin regimen at home. Careful blood glucose monitoring should be instituted as well to make sure the animal does not become hypoglycemic. An underlying cause for its sudden poor glycemic control should also be investigated. Commonly, underlying conditions such as pancreatitis, urinary tract infection, or other underlying infections are responsible for disrupting a diabetic's glycemic control, making them go into DKA. ***PowerPage: Diabetes Mellitus

Answer 79

Answer: **Cutaneous lymphoma** Explanation This is a common presentation for cutaneous lymphoma (mycosis fungoides). Patients with this cancer will often be worked-up for allergies because many are pruritic. However, most cases of allergies will not have lesions affecting the oral mucosa or foot pads. It is important to have cutaneous lymphoma on your list of differentials for older patients with skin disease who are not responding to conventional therapy. Although, mast cell tumors can cause pruritus through release of histamine, the clinical presentation is not consistent with a mast cell tumor. Mast cell tumors are variable in appearance but usually do not cause generalized exfoliative erythroderma or affect the mucous membranes. Sebaceous adenomas are benign tumors of the sebaceous glands that appear as "wart-like" masses. Histiocytomas are usually present in younger dogs as a soft well-circumscribed pink mass. These tumors regress spontaneously. Liposarcomas are poorly circumscribed infiltrative masses. They are usually solitary, but can be multiple. ***PowerPage: Tumors of the Skin

Answer 80

Answer: **C1-C5 of the spinal cord** Explanation The correct answer is C1-C5 of the spinal cord. All 4 limbs are showing signs of an upper motor neuron lesion, which would be consistent with a C1-C5 myelopathy or multifocal spinal lesions. A C6-2 lesion would manifest as lower motor neuron signs in the thoracic limbs and upper motor neuron signs in the pelvic limbs. A T3-L3 lesion would manifest as upper motor neuron signs in the pelvic limbs with normal thoracic limbs. A L4 and caudal lesion would manifest as lower motor neuron signs in the pelvic limbs with normal thoracic limbs. Remember that multifocal lesions in different areas of the spinal cord can make neuroanatomic localization trickier.

Answer 81

Answer: **The dog suffered a brachial plexus avulsion and will most likely need to have the leg amputated.** Explanation The correct answer is the dog suffered a brachial plexus avulsion and will most likely need to have the leg amputated. Dogs that are hit by cars or who jump out of moving cars often suffer brachial plexus avulsions. Complete nerve root avulsions are not treatable and usually require amputation of affected limbs. Partial avulsions carry a better prognosis but require large amounts of time and physical therapy before seeing any improvement. The lack of deep pain and motor function in the limb is a negative prognostic indicator supporting the diagnosis of a complete brachial plexus avulsion.

Answer 82

Answer: **Prothrombin time (PT)** Explanation The correct answer is PT. These compounds act by inhibiting vitamin K, which is required for synthesis of clotting factors II, VIl, IX, and X. Factor VII has the shortest half-life of these and will be depleted first. Since PT measures the extrinsic system which contains factor VII, it becomes prolonged first.

Answer 83

Answer: **Perform radiographs** Explanation The correct answer is to obtain a radiograph. This question can potentially be controversial as to what is the correct answer. In this case, radiograph is a good choice because you are dealing with an older small breed dog which would have a higher likelihood of malpositioning or malformation. Giving oxytocin to an animal when the fetus is unable to fit through the pelvic canal may result in uterine tear or rupture.

Answer 84

Answer: **Melanoma** Explanation The cytology shows cells with large nuclei, stippled chromatin with prominent and sometimes multiple nucleoli (labeled with 1). A few cells (labeled with a 2) have dark green/black melanin granules. Melanoma is an important differential for a nail bed tumor. At this site, they are frequently malignant and the local lymph node should be palpated and aspirated. Additional staging (thoracic radiographs and abdominal ultrasound) should also be considered. If there is no evidence of metastasis, the affected digit should be amputated.

Answer 85

Answer: **Blastomyces dermatitidis** Explanation The correct answer is Blastomyces dermatitidis. You can come to this diagnosis by thinking about the clinical findings and travel history, which are both characteristic for blastomycosis. On cytology you can expect to see a 5-20 micrometer diameter thick, refractile, double-contoured cell wall, and broad-based budding organism. Transmission is a result of spores inhaled from the environment which form yeast in the lungs and then disseminate through the blood and lymphatics. Itraconazole is usually the drug of choice for uncomplicated disease. Histoplasmosis usually occurs in the Ohio, Mississippi, and Missouri river valleys, but skin and ocular lesions occur uncommonly. Usually, you will see Gl involvement, especially large bowel. Usually, with histoplasmosis you will see large numbers of small round bodies with a basophilic center in mononuclear phagovtes from vour sample.

Answer 86

Answer: **Medial meniscus** Explanation The correct answer is medial meniscus. The medial meniscus is commonly damaged in a dog with a ruptured cranial cruciate ligament because the meniscus is closely associated with the medial collateral ligament, which prevents the meniscus from moving around within the joint when the femoral condyle compresses and slides against it. When there is joint instability following the CCL rupture, the medial collateral ligament is no longer able to prevent movement of the medial meniscus and damage occurs. The lateral meniscus is not associated with the collateral ligament and can freely move around when compressed by the femur. ***PowerPage: Cruciate Ligament Disease ***PowerLecture: Cranial Cruciate Ligament Rupture

Answer 87

Answer: **Chronic superficial keratitis** Explanation The answer is chronic superficial keratitis, sometimes referred to as pannus. It is a condition seen mainly in German Shepherd and shepherd crosses and is due to UV light exposure. It is believed that the UV light alters corneal proteins leading to an immune reaction. It is treated with topical steroids and cyclosporine, and animals often require lifelong therapy. KCS is not the correct choice because of the normal tear test. Lymphoma in the eye should cause changes in the uvea or retina but rarely the cornea.

Answer 88

Answer: **Second degree Mobitz I heart block** Explanation The correct answer is Second degree Mobitz type I heart block, also known as the Wenckebach beat. In a Mobitz type Il block, the P-R interval duration is unchanged and occasionally you will observe a P wave without a QRS complex. These blocks are thought to be caused by a refractory AV node which is not responding to a delayed atrial depolarization. In a 1st degree heart block, you will observe an increased P-R interval and no dropped QRS. In 3rd degree heart blocks, the P waves are unassociated from the QRS complex.

Answer 89

Answer: **Incorporating gastropexy** Explanation The correct answer is incorporating gastropexy. This technique is easy and rapid to perform. It involves making an incision through the seromuscular layer of the stomach and then suturing it to the linea alba as you are closing your incision. As a result, if one ever goes back into the abdomen, there is a risk of cutting into the stomach since it will be adhered to the linea alba. For this reason, some surgeons will advise against this procedure. A circumcostal gastropexy involves wrapping a section of the seromuscular layer of the stomach around a rib and then suturing it back onto the stomach. An incisional gastropexy involves making an incision onto the abdominal wall and the seromuscular layer of the stomach, and then suturing them together so the stomach ends up sutured up against the body wall. A belt loop gastropexy involves making two parallel incisions into the abdominal wall musculature and then passing a section of seromuscular layer of the stomach through one incision, out the other, and then suturing it back onto the stomach. An endoscopically-assisted gastropexy is a method of performing a fast and relatively easy prophylactic gastropexy.

Answer 90

Answer: **German Shepherd** Explanation The correct answer is German Shepherd Dog. EPI is believed to be an autosomal recessive trait in German Shepherd Dogs that results in atrophy of the exocrine pancreas. Dogs lose the ability to digest fat and protein and become emaciated. They have voluminous, soft feces, a voracious appetite, and may develop pica. The trypsin-like immunoreactivity (TLI) is diagnostic for EPI. Treatment entails adding powdered pancreatic enzyme extract, or raw pancreas to meals. These dogs should not be bred.

Answer 91

Answer: **Metabolic acidosis** Explanation The correct answer is metabolic acidosis. A low bicarbonate and total CO2 level is consistent with a metabolic acidosis. An elevated blood lactate of greater than 2.0 mmol/L implies that there is anaerobic metabolism occurring in this patient as a result of inadequate tissue perfusion, perhaps due to bleeding and trauma. Nothing can be said about respiratory acidosis or alkalosis because no PaCO2 or pH is provided.

Answer 92

Explanation This is a description of septic arthritis based primarily on the cytologic findings of neutrophils and bacteria in the joint fluid cytology. Note that the bacteria are within the neutrophils (intracellular bacteria) which assures that this is not contamination on your slide. There is no other likely explanation for such a finding. The dog's clinical presentation of nonspecific signs and mild lameness or decreased weight bearing is consistent with this diagnosis. There may be a history of trauma to the affected joint that allowed for entry of bacteria, but such an instance is not always identified. The bloodwork is within normal limits. Occasionally, systemic signs of inflammation or infection may be present with septic arthritis but if the infection is contained within the joint, it is common for bloodwork to be unremarkable. All of the answer choices might be reasonable recommendations but the most important diagnostic test is to culture the joint fluid to determine the etiologic agent and its antibiotic susceptibility as this will most directly impact your choice of therapy. The treatment of choice for septic arthritis is a prolonged (at least one month) course of an appropriate antibiotic. In some cases, drainage/lavage of the joint or surgery may be necessary. Total protein of the joint fluid can be helpful to classify it and monitor changes with treatment. Urinalysis or echocardiogram might be indicated if you were suspicious that the septic joint was the result of hematogenous spread of bacteria from another site such as a subclinical urinary tract infection or valvular endocarditis. Arthroscopy might be useful to better examine and to flush the joint.

Answer 93

Answer: **Bacterial or white blood cell casts in urine** Explanation The correct answer is bacterial or white blood cell casts in urine. Bacterial or white blood cell casts are highly suggestive of a past or present bacterial infection in the kidneys. Bacteria or white blood cells in the urine may be due to cystitis. Small, irregular kidneys may be due to any chronic pathology in the kidneys. Pain on abdominal palpation can be caused by pain from any abdominal organ or structures adjacent to the abdomen. Other signs associated with pyelonephritis include fever, anorexia, depression, and vomiting. A nephropyelogram may show blunted, dilated calices and dilated, tortuous ureters. Renal biopsy and culture would give the definitive diagnosis of pyelonephritis.

Answer 94

Answer: **Low dose dexamethasone suppression test** Explanation The 8-hour post-dexamethasone sample is used to determine if the pet has hyperadrenocorticism. If the 8-hour sample is above 1.4 ug/dL, the test is diagnostic for hyperadrenocorticism (either pituitary dependent or adrenal dependent). If the 4-hour sample is below 1.4 ug/dL or less than half of the baseline value, it is diagnostic for pituitary dependent hyperadrenocorticism. The urine cortisol:creatinine ratio is a screening test to rule out hyperadrenocorticism, if it is normal. The endogenous ACTH level and high dose dexamethasone suppression tests are differentiating tests only. An АСТН stimulation test is a screening test but cannot differentiate pituitary versus adrenal dependent hyperadrenocorticism. ***PowerPage: Hyperadrenocorticism (Cushing's Disease)

Answer 95

Answer: **Toxocara canis infection** Explanation The correct answer is Toxocara canis infection. Toxocara canis is a canine roundworm that is passed along to puppies transplacentally. The roundworms migrate from the small intestines through the liver and lungs, which is what causes the animal to cough. Beyond 6 months of age, the larvae distribute to the somatic tissue, where their development is arrested. Dirofilaria immitis or heartworm disease takes at least 6 months before the infection is patent. It would take even longer for the infection to progress to congestive heart failure, causing the dog to cough. Trichuris vulpis, the canine whipworm, and Toxascaris leonina, another canine roundworm, do not migrate through the lungs.

Answer 96

Answer: **Epithelial origin; carcinoma** Explanation This is a nasal adenocarcinoma. The classification scheme for tumors by cell of origin and cytologic description is: Carcinoma- These tumors come from epithelial cells including cells of glandular tissues such as salivary glands, mammary glands, and cells lining most tissues including squamous cells or transitional cells. The cytologic appearance is that of COHESIVE CLUSTERS of cells. Here, you can see some of the tight cellular junctions in the cluster which is typical. Cells are often polygonal in shape. Sarcoma- These tumors come from mesenchymal cells and are named by the specific cell type such as fibroblasts (fibrosarcoma) and osteoblasts (osteosarcoma). Cytologically, they tend to appear as isolated spindle-shaped cells with elongated cytoplasm and often oval nuclei. Round cell tumors- There are 5 round cell tumors and most but not all come from blood cells. They are lymphoma, mast cell tumors, plasma cell tumors, histiocytic tumors, and transmissible venereal tumors. Remember, these are also sometimes also referred to as sarcomas (i.e. lymphosarcoma or histiocytic sarcoma). Cytologically, they appear usually as large populations of cells that are not in defined clusters. The cells have a round shape, often with unique identifiable features such as the purple granules in mast cell tumors. ***PowerLecture: Nasal Tumors

Answer 97

Answer: **Compensatory increase in mean arterial pressure to maintain cerebral perfusion pressure** Explanation The correct answer is a compensatory increase in mean arterial pressure to maintain cerebral perfusion pressure. Cerebral perfusion pressure= Mean arterial pressure - intracranial pressure or (CPP=MAP-ICP). This response is seen in situations where intracranial pressure increases such as in brain trauma. In this case, you need to think before you intervene to decrease your patient's mean arterial pressure as this might eliminate cerebral blood flow and kill your patient.

Answer 98

Answer: **Toggle pin fixation** Explanation Since this hip has luxated again and it has likely been going on for a couple of days, an open reduction surgery would now be recommended. Since the hip bones are otherwise healthy, a toggle pin fixation would be the best option for this dog. If there were a fracture or severe osteoarthritis present, a total hip replacement or FHO would be other options to consider. Amputation would not be an option for this condition.

Answer 99

Answer: **Cystitis** Explanation The correct answer is cystitis. In addition to the usual side effects of chemotherapeutic drugs such as myelosuppression and Gl side effects, a major concern with cyclophosphamide administration is causing sterile hemorrhagic cystitis due to a breakdown product of the drug called acrolein. To reduce this risk, animals should be encouraged to drink lots of water or be given fluids and encouraged to urinate frequently to prevent the toxic compound from sitting in the bladder for a long time. The drug that causes cardiotoxicity is doxorubicin. The drug that causes ileus is vincristine. The drug that causes anaphylaxis is L-asparaginase. The drug that causes nephrotoxicity is cisplatin.

Answer 100

Answer: **Canine idiopathic vestibular disease (Old dog vestibular disease)** Explanation The correct answer is canine idiopathic vestibular disease (Old dog vestibular disease). This disease is usually diagnosed after all other vestibular causes have been ruled out. Otitis interna would be ruled out with an otic exam, CBC, and lack of pain and fever. Bacterial meningitis could be ruled out by a CBC and lack of pain and fever. Polyps in the ear rarely occur in dogs; most aural polyps occur in cats. In addition, an otic exam would rule this out anyway.

Answer 101

Answer: **Direct fecal smear** Explanation Giardia trophozoites and cysts are typically found on a direct fecal smear. Giardia cysts can be found on fecal flotation also. The organism can also be detected by FA and ELISA. The Baermann technique is a method of recovering larvae from fecal material and is most commonly used when looking for nematode parasites, most often lungworm. Here is an image of a Giardia trophozoite:

Answer 102

Answer: **Polyostotic, aggressive** Explanation There are multiple lytic lesions in the cervical and thoracic vertebrae, especially visible in C2 and in the spinous processes of the T1-T8. There are also lytic lesions in the proximal humerus of one leg and in the bones of the skull.

Answer 103

Answer: **You are most concerned about a severe and potentially life-threatening cutaneous drug reaction and the dog should be hospitalized for supportive care and testing** Explanation The history and clinical appearance are very concerning for toxic epidermal necrolysis which is usually associated with an adverse reaction to a drug. In severe cases such as the dog shown in this image, there is concern for extensive loss of fluids, electrolytes, and colloids as well as secondary bacterial infection of the skin. Concurrent medications should be withdrawn and aggressive supportive care, analgesia, and use of a different antibiotic protocol are indicated. The prognosis is guarded depending on response to removal of a suspected inciting cause. The other possibilities listed in this question are less consistent with the cutaneous lesions shown and the very rapid onset and progression as well as the histopathologic findings.

Answer 104

Answers **30 mL** Explanation The correct answer is 30 mls. 25% corresponds to 250 mg/ml strength. At a dose of 500 mg/kg, the total dose for a 15 kg dog should be 7,500 mg which divided by 250 mg/ml equals 30 mls.

Answer 105

Answer: **Thoracic radiographs** Explanation Blastomycosis is caused by a dimorphic fungus and generally occurs in the Missouri, Mississippi, Tennessee, and Ohio river valleys. Pulmonary involvement occurs in the majority of cases, so thoracic radiographs are an important step to staging the patient. Other organs that can be affected include the lymph nodes, eyes, bones, central nervous system, and urinary tract. Abdominal radiographs are not very sensitive to detect involvement with internal organs. Abdominal ultrasound, if available, would be preferred over abdominal radiographs. Antibody tests are neither sensitive nor specific and are not very useful once a diagnosis is already made.

Answer 106

Answer: **Arthroscopy for evaluation and treatment of fragmented medial coronoid process** Explanation The radiographic findings are consistent with a fragmented medial coronoid process. A CT scan may be recommended to help evaluate the joint prior to arthroscopy; however, this was not offered as a choice. During arthroscopy the surgeon will be able to carefully evaluate the joint for other components of elbow dysplasia such as OCD and elbow incongruency. In addition to evaluation, the surgeon will also be able to treat the condition by performing a sub-total coronoidectomy and removing and diseased cartilage if OCD is present. ***PowerPage: Elbow Dysplasia

Answer 107

Answer: **Previous distemper virus infection** Explanation The correct answer is previous distemper virus infection. Infection before the eruption of permanent dentition occurred to this dog. Many consider this finding pathognomonic for previous infection. Tetracycline administration to young dogs may lead to yellow discoloration of the teeth. Congenital enamel hypoplasia is extremely rare in dogs. All other choices are not accurate.

Answer 108

Answer: **Invasion into the vena cava is not necessarily associated with an increased mortality rate, and surgery should still be considered.** Explanation Uncontrolled hypertension is associated with an increased mortality rate. Interestingly, in a recent study, pretreatment with phenoxybenzamine for several weeks prior to surgery in order to control hypertension showed an increase in survival time. As long as the pheochromocytoma is being removed by a skilled surgeon familiar with vascular surgery, there is no increase in mortality noted if caval thrombosis is present; however, invasion of disease such that a nephrectomy needs to be performed is associated with increased mortality.

Answer 109

Answer: **Increased folate, decreased cobalamin** Explanation The correct answer is increased folate, decreased cobalamin. The reason for this is that bacteria synthesize folate leading to decreased absorption of cobalamin.

Answer 110

Answer: **Corneal scarring** Explanation Chronic uveitis can lead to cataract formation and corneal scarring because the inflammatory mediators in the anterior chamber can destroy corneal and lens proteins. It can lead to glaucoma when debris from uveitis plugs the iridocorneal angle. Uveitis cannot extend into the lacrimal glands and destroy them, and thus doesn't cause KCS. PRA occurs when the photoreceptors in the retina develop abnormally, causing early onset blindness. It is a heritable disease and not caused by chronic anterior uveitis.

Answer 111

Answer: **Treatment with a flea adulticide and insect growth regulator** Explanation The distribution of lesions is highly suggestive of flea allergy dermatitis. Although the patient is on flea control (Lufenuron), this is usually not adequate to control fleas in a dog with flea allergies. Lufenuron is only an insect growth regulator and does not have any effect on adult fleas. Pododermatitis is not typical of flea allergy and may be due to another allergy (food/environmental). If an acceptable pruritus level is not achieved after flea treatment, then further work-up of allergies will be necessary. This may include a diet trial to rule out food allergy and/or an intradermal or serum allergy test to develop an allergy vaccine for immunotherapy. ***PowerPage: Flea Allergy Dermatitis

Answer 112

Answer: **Hansen's Type 1 disc disease usually involves chondrodystrophic dogs. tis usually acute, painful, and should be considered an emergency.** Explanation The correct answer is Hansen's Type 1 disc disease usually involves chondrodystrophic dogs (Dachshunds, Corgis, Shih-Tzus, etc.). It is usually acute, painful, and should be considered an emergency.

Answer 113

Answer: ** Explanation The correct answer is exposure keratitis. CN VIl is responsible for lacrimation. Deficits in lacrimation would cause exposure keratitis. Loss of motor function in the muscles of mastication would occur in CN V (mandibular branch) deficits. Strabismus of the eyes would be caused by deficits in CN Ill (oculomotor nerve), CN IV (trochlear nerve) or CN VI (abducent nerve). Nystagmus occurs with CNS disease or CN VIII deficits.

Answer 114

Answer: **Azathioprine, prednisone, cyclophosphamide** Explanation For patients with immune-mediated thrombocytopenia, immunosuppressive doses of corticosteroids should be started. Cyclophosphamide can be given to help induce remission. Azathioprine can help maintain remission and can be given long-term, usually with fewer side effects than with corticosteroids. Doxycycline would be given for patients with Ehrlichiosis. Famotidine would be helpful in preventing stomach ulcers while administering corticosteroids. Vitamin K would be given to patients who ingested Vitamin K antagonists like warfarin or brodifacoum (the drugs found in rat poisons). Aspirin would be contraindicated as aspirin decreases platelet aggregation.

Answer 115

Answer: **Castration** Explanation Based on the history and ruling out other endocrinopathies this patient likely has hair cycle arrest (Alopecia X). The pathogenesis of this disease is not known. This condition is common in Pomeranians, Chow Chows, Alaskan Malamutes, Toy Poodles, and Samoyeds. The most common clinical signs are truncal alopecia and hyperpigmentation. The treatment of choice (if the dog is intact) is to neuter; however, it is not uncommon to see a relapse in clinical signs 1-2 years after neutering. Melatonin may help new hair to grow if a relapse occurs. Trilostane, mitotane, and growth hormone supplementation have been tried with varying success. Levothyroxine is a thyroid supplement and would not be indicated.

Answer 116

Answer: **Iron deficiency** Explanation The correct answer is iron deficiency. The CBC shows a microcytic, hypochromic, non-regenerative anemia. Reticulocyte counts under 60,000/ul are typically considered non-regenerative in most labs. This is consistent with chronic iron deficiency. This most common reason for chronic blood loss is gastrointestinal tract disease such as an ulcer or cancerous lesion.

Answer 117

Answer: **Neomycin, bacitracin, and polymyxin B** Explanation This patient has a high number of malassezia yeast visualized on cytology. This organism can be responsible for perpetuating otitis externa. It is not unusual to see yeast in the ear canal of a dog; however, yeast numbers of greater than 5 per high powered field can be considered abnormal. Other clinical signs of otitis externa may include ear pain, pruritis, aural discharge, bad odor, and neurologic signs. Effective treatments for uncomplicated otitis externa typically contain an antifungal, antibiotic, and an anti-inflammatory. Since this dog primarily has a yeast infection it is imperative that the ear medication prescribed has an anti-fungal. The answer choices provided are commonly known as triple antibiotic ointment (neomycin, bacitracin, and polymyxin B), Tresaderm (thiabendazole, neomycin, and dexamethasone), Mometamax (mometasone, gentamicin, clotrimazole), and Otomax (gentamicin, betamethasone valerate, and clotrimazole). Note that the triple antibiotic ointment does not contain an anti-fungal. Additionally, the ears should be cleaned before applying the ear medication. Many ear cleaners contain antifungals too (Triz Ultra + Ketoconazole), which may enhance treatment response.

Answer 118

Answer: **Right cerebellum** Explanation The correct answer is the right cerebellum. This dog has a left head tilt by definition because his left ear is closer to the ground. The key to answering this question is seeing the left head tilt and reading that the question asks about PARADOXICAL vestibular disease. Vestibular disease can be peripheral or central, and central vestibular disease can be classic in appearance or paradoxical. Peripheral vestibular disease is due to a lesion in the inner ear or vestibular portion of cranial nerve VIII. Classic central vestibular disease is due to a lesion in the brainstem or cerebellum. Signs with peripheral and classic central vestibular disease include head tilt, falling, and circling to the same side as the lesion with nystagmus with fast phase to the opposite side. With paradoxical vestibular disease, the lesion is in certain regions of the cerebellum (flocculonodular lobe) or caudal cerebellar peduncle and produces signs to the opposite sides from which is seen with peripheral and classic central disease.

Answer 119

Answer: **Hypoproteinemia** Explanation The correct answer is hypoproteinemia. The calcium measured on a chemistry panel is the protein-bound calcium, which will appear low if the animal is hypoproteinemic. The ionized form of calcium is the active form and is not affected by an animal having a low blood protein level; therefore, when the total calcium on a chemistry panel is low due to hypoproteinemia, you should not see clinical signs of hypocalcemia as long as the ionized calcium is normal. The remaining answer choices cause an actual decrease in ionized calcium, causing clinical signs of hypocalcemia.

Answer 120

Answer: **Strict cage rest** Explanation By far, the most likely diagnosis is intervertebral disc disease (IVDD) based on the history and myelogram showing a collapsed intervertebral space at T12-13 and an extradural compressive lesion originating from the same site. IVDD can be managed by surgical decompression or non-surgically. The most important aspect of non-surgical management of IVDD is STRICT cage rest, usually for a full 8 weeks. Exercise should be avoided during the period of cage rest. Steroids, analgesics, and/or muscle relaxants may be useful additions to the management of these dogs.

Answer 121

Answer: **External abdominal oblique** Explanation The external abdominal oblique is a component of the external inguinal ring. All others make up the internal inguinal ring. The rectus abdominis makes up the medial border. The inguinal ligament makes up the lateral and caudal border. Finally, the internal abdominal oblique makes up the cranial border.

Answer 122

Answer: **Cranial cruciate ligament disease** Explanation The correct answer is cranial cruciate ligament disease. Approximately 30% of dogs evaluated for hip dysplasia have a cranial cruciate ligament injury (M. Powers JAVMA 2005). Dogs with hip dysplasia don't acutely decompensate as the patient described in this question. All dogs should be thoroughly evaluated, as you should not send a dog home on medical management for hip dysplasia or recommend a total hip replacement when the immediate problem (and source of discomfort) is the stifle. Capital physeal dysplasia is a disease of young male neutered cats that are usually obese. This usually manifests as a fracture across the femoral head physis. Aortic thromboemboli are very rare in dogs. A peripheral nerve sheath tumor usually has a gradual onset in clinical signs. Many hips are actually subluxated in patients with severe hip dysplasia. Subluxation secondary to hip dysplasia is not typically a cause of acute lameness.

Answer 123

Answer: **Exposure keratitis** Explanation The correct answer is exposure keratitis. CN VII is responsible for lacrimation. Deficits in lacrimation would cause exposure keratitis. Loss of motor function in the muscles of mastication would occur in CN V (mandibular branch) deficits. Strabismus of the eyes would be caused by deficits in CN Ill (oculomotor nerve), CN IV (trochlear nerve) or CN VI (abducent nerve). Nystagmus occurs with CNS disease or CN VIII deficits.

Answer 124

Answer: **Microsporum canis (cats); Microsporum gypseum (soil), Trichophyton mentagrophytes (rodents)** Explanation Microsporum gypseum is geophilic (meaning that it loves to grow in soil). This species often affects dogs that like to dig. Trichophyton mentagrophytes is zoophilic and usually rodents serve as the host; dogs such as hunting dogs or roaming cats are most commonly affected. Microsporum canis is most commonly contracted from cats. It is extremely important to know which species of dermatophyte is causing the infection in order to prevent re-exposure. For example, in dogs with Microsporum gypseum, preventing them digging in the yard is going to be an important part of the treatment plan.

Answer 125

Answer: **Schistocytes** Explanation Schistocytes are fragmented red blood cells that are mechanically broken up due to the irregular vessels and fibrin strands they pass through in hemangiosarcoma patients. Other typical findings on a CBC in a patient with hemangiosarcoma are thrombocytopenia, anemia (although not with Heinz bodies), and leukocytosis. [Schistocytes](https://eclinpath.com/hematology/morphologic-features/red-blood-cells/poikilocytosis/) Notability: **Hemangiosarcoma** [Heinz bodies](https://eclinpath.com/hematology/morphologic-features/red-blood-cells/rbc-inclusions/)

Answer 126

Answer: **Perianal adenoma** Explanation The correct answer is perianal adenoma. These tumors are primarily seen in older male intact dogs. These tumors will often shrink or resolve after castration.

Answer 127

Answer: **Mandibular branch** Explanation The correct answer is mandibular branch. The mandibular branch supplies innervation to the muscles of mastication (temporalis, masseter, medial and lateral pterygoids, rostral digastricus, and mylohyoid). The maxillary and ophthalmic branches contain sensory afferents to the eyes, face, eyelids, pinnae, corneas, nasal septum, etc. There is no such thing as the facial branch of the trigeminal nerve. The facial nerve is CN VII.

Answer 128

Answer: **There is a less than 7% incidence of post-operative medial meniscal injury rate after a tibial plateau leveling osteotomy** Explanation Studies show a post-operative meniscal injury rate ranging between 2-7% when performing a tibial plateau leveling osteotomy. This is in contrast to a study on the tibial tuberosity advancement procedure which had a much higher incidence of post-operative medial meniscal tears. The two most common meniscal injuries observed are the bucket handle tear (caudal longitudinal tear) and a "crush" of the caudal horn of the meniscus (this is essentially an incomplete bucket handle tear). The outer 25-30% of the meniscus is avascular which helps explain why meniscal injuries don't heal well. Additionally, the inner 2/3 of the meniscus is also avascular. This level of detail is probably greater than what you will need to know for a board examination but it is important to understand that performing a meniscal release at the time of cruciate ligament surgery may not be indicated based on the low probability of post-operative injury to this structure.

Answer 129

Answer: **Epiphysis and physis** Explanation The correct answer is the epiphysis and physis. A type I Salter-Harris fracture is physeal only. Type Il involves the physis and metaphysis, type Ill involves the physis and epiphysis, type IV involves physis, metaphysis, and epiphysis, and type V is a compression injury to the physis.

Answer 130

Answer: **Both are diffuse changes throughout the lens, but the animals can see through an incomplete cataract.** Explanation The correct answer is that both are diffuse changes throughout the lens, but the animals can see through an incomplete cataract. An incomplete cataract is not completely opacified and a tapetal reflection can be seen through it. The animal can see through an incomplete cataract, albeit probably not as clearly as through a normal lens. A complete cataract is a completely opacified lens that cannot be seen through and through which a tapetal reflection cannot be seen. A focal cataract is referred to as an incipient cataract. The normal aging change to the center of the lens is nuclear sclerosis. Degradation of lens proteins after developing a cataract is termed a resorbing cataract.

Answer 131

Answer: **Heartworm disease** Explanation Although all of these are associated with PTE, dirofilaria or heartworm is the most commonly recognized cause.

Answer 132

Answer: **43 days gestation** Explanation The correct answer is 43 days gestation. The fetal skeleton ossifies at 42-45 days in the dog and 35-39 in the cat. In the dog, a mineralized fetus can usually be seen around 42-46 days. The scapula, humerus, and femur can be made out around 46-51 days. The ribs can be seen at 52-59 days. Teeth and toes can be seen at 58-63 days. For the PowerLecture'" on this topic, view Estrous Cycle Part 3 (5:52)

Answer 133

Answer: **Azotemia** Explanation The correct answer is azotemia. The classic laboratory finding for an Addisonian includes hyponatremia, hyperkalemia, azotemia, anemia, acidosis, hypoglycemia, and of course a low resting cortisol level or low ACTH stimulation test result.

Answer 134

Answer: **Respiratory depression** Explanation Mu agonist opioids, such as morphine, hydromorphone, and Fentanyl may cause CNS depression, decreased intestinal motility, respiratory depression, and decrease in body temperature. Other side effects include panting, cough suppression, and bradycardia. Sometimes, opioids may cause a transient hyperthermia in cats.

Answer 135

Answer: **A branch of the facial nerve is responsible for taste in the rostral 2/3 of the tongue** Explanation The chorda tympani nerve, which branches off CN VII, is responsible for taste in the rostral 2/3 of the tongue. While conditions such as otitis media can be seen concomitant to facial nerve and vestibular signs, these occur due to effects on CN VIII (auditory-vestibular nerve), not CN VII. CN VIII transmits sound from the inner ear to the brain. Otitis media (not externa) often causes deficits in CN VIlI and CN VII, since the two nerves run adjacent to each other through the middle ear.

Answer 136

Answer: **Epiphysis and physis** Explanation The correct answer is the epiphysis and physis. A type I Salter-Harris fracture is physeal only. Type II involves the physis and metaphysis, type III involves the physis and epiphysis, type IV involves physis, metaphysis, and epiphysis, and type V is a compression injury to the physis.

Answer 137

Answer: **Hypoallergenic diet trial** Explanation A diet trial is considered an important diagnostic test to rule out dietary intolerances in animals with suspected inflammatory bowel disease (IBD). It is not wrong to pursue the other diagnostic options, but many internists will recommend a strict diet trail to start. Some patients will respond so favorably that additional testing may not be necessary. To definitively diagnose IBD you will need a biopsy and histopathology, and it is important to warn the clients that this is a disease to be managed, not necessarily cured.

Answer 138

Answer: **Praziquantel** Explanation The correct answer is *praziquantel*. Pyrantel and ivermectin are not known to be effective against Taenia infections. Fenbendazole is effective against Taenia pisiformis, but not other subspecies of Taenia, making it a less desirable answer choice. ChGPT: **Tapeworms** [Tapeworms in Dogs and Cats](https://www.merckvetmanual.com/digestive-system/gastrointestinal-parasites-of-small-animals/tapeworms-in-dogs-and-cats?query=Taenia%20canine) **Praziquantel** Uses/Indications Praziquantel is indicated for (FDA-approved labeling) for the treatment of Dipylidium caninum, Taenia pisiformis, and Echinococcus granulosis in dogs, and Dipylidium caninum and Taenia taeniaeformis in cats. Fasting is not required nor recommended before dosing. A single dose is usually effective, but measures should be taken to prevent reinfection, particularly against D. caninum. Praziquantel can also be used for treating Alaria spp. in dogs and cats and Spirometra mansonoides infections in cats. Praziquantel has been used in birds and other animals, but it is usually not economically feasible to use in large animals. In humans, praziquantel is used for schistosomiasis, other trematodes (lung, liver, intestinal flukes) and tapeworms. It is not routinely effective in treating F. hepatica infections in humans. Combination products can give a wide spectrum of internal parasite control in a variety of species. Pharmacology/Actions Praziquantel's exact mechanism of action against cestodes has not been determined, but it may be the result of interacting with phospholipids in the integument causing ion fluxes of sodium, potassium and calcium. At low concentrations in vitro, the drug appears to impair the function of their suckers and stimulates the worm's motility. At higher concentrations in vitro, praziquantel increases the contraction (irreversibly at very high concentrations) of the worm's strobilla (chain of proglottids). In addition, praziquantel causes irreversible focal vacuolization with subsequent cestodal disintegration at specific sites of the cestodal integument. In schistosomes and trematodes, praziquantel directly kills the parasite, possibly by increasing calcium ion flux into the worm. Focal vacuolization of the integument follows and the parasite is phagocytized.

Answer 139

Answer: **Septic Peritonitis** Explanation The most common complication of this surgery is leakage at the surgery site, resulting in septic peritonitis. An abdominal tap and labwork should be performed. The dog should be stabilized immediately and will need to go back to surgery. While acute renal failure can be a sequelae of sepsis, the most immediate concern is to find out if the bowel has leaked. The most common time for anastomosis failure is 3-5 days postoperative. This is due to the timing of degradation of fibrin at the site prior to deposition of sufficient collagen.

Answer 140

Answer: **Pancreatic Enzyme Replacement for the life of the dog** Explanation TLI (canine trypsin-like immunoreactivity) levels <2.5 ug/L along with clinical disease are highly suggestive of Exocrine Pancreatic Insufficiency (EPI). EPI is a deficiency of pancreatic enzymes which causes a disease of maldigestion. EPI is treated with pancreatic enzyme replacement for the life of the patient, because that portion of the pancreas is destroyed and will not recover. This patient does not need to be hospitalized for dehydration or gastric symptoms as those are not severe or not present. This patient does not need supplemental feeding as the pancreas cannot digest the food anyway. The diarrhea is not due to Giardia or indiscriminate eating, so metronidazole and probiotics are not necessary. ChGPT: **Exocrine Pancreatic Insufficiency (EPI)**

Answer 141

Answer: **Pleural fissure lines on both lateral and ventrodorsal projections** Explanation Pleural fissure lines are typically diagnostic for pleural effusion. The fissures are the normal divides between the lung lobes and are not visualized on radiographs unless there is fluid in the chest or the pleura is very thickened. When there is a large amount of fluid, you may begin to appreciate a loss of detail, and it is possible lung lobes will collapse as a result of an inability to properly expand in the face of the pleural effusion. A lobar sign is seen when there is a line of demarcation between a radiopaque (consolidated) lung lobe and a radiolucent (normal) lung lobe. There can be several causes for a lobar sign including hemorrhage, edema, or pus within the lobe. An air bronchogram is seen when alveolar edema occurs as a result of fluid accumulating within the alveoli. Alveolar edema will result in a sharp contrast between the fluid in the alveoli and the air in the bronchi.

Answer 142

Answer: **Unilateral arytenoid lateralization** Explanation The correct answer is unilateral arytenoid lateralization. Resection of the soft palate is performed when dogs have respiratory problems as a result of having an elongated soft palate. Resection of the laryngeal saccules is performed when they are everted and causing respiratory distress. A partial laryngectomy is pertormed in cases where there may be a mass or tumor to be removed. For the PowerPage: Laryngeal Paralysis Article: **Surgical Management of Laryngeal Paralysis** **Laryngeal paralysis** is a condition characterized by the inability of the laryngeal cartilages to open and close properly during respiration, leading to compromised airflow. This disorder is common in dogs and rare in cats. Etiology: • Acquired Laryngeal Paralysis: Typically observed in middle-aged to older, large and giant dog breeds such as Labrador Retrievers, Irish Setters, and Great Danes. The exact cause often remains unidentified, but it may be associated with generalized polyneuropathy, trauma, neoplasia affecting the neck or mediastinum, or hypothyroidism. • Congenital Laryngeal Paralysis: Less common and seen in breeds like Bouvier des Flandres, Leonbergers, Siberian Huskies, Bulldogs, and racing sled dogs. This hereditary form presents early in life. Pathophysiology: The larynx functions to regulate airflow into the trachea and lungs. In laryngeal paralysis, there is a dysfunction of the recurrent laryngeal nerves, leading to paralysis of the cricoarytenoid dorsalis muscle. This results in the failure of the arytenoid cartilages to abduct during inspiration, causing airway obstruction. Over time, this can lead to increased respiratory effort, stridor, and potential respiratory distress. Clinical Signs: • Respiratory Distress: Noisy breathing (stridor) that worsens with stress or exertion. • Voice Changes: Alterations in vocalization, such as a hoarse bark in dogs. • Coughing: Dry cough, which may be exacerbated during eating or drinking. • Exercise Intolerance: Reduced ability to perform physical activities. • Collapse: In severe cases, especially during periods of excitement or heat stress. The progression of clinical signs is typically slow, developing over months to years before significant respiratory distress becomes evident. Diagnosis: • Clinical Evaluation: Observation of clinical signs and breed predisposition. • Laryngoscopy: Performed under light anesthesia to visualize laryngeal function. Affected animals exhibit absent or paradoxical laryngeal movements during respiration. • Electromyography: May reveal denervation potentials, positive sharp waves, and occasionally myotonia in laryngeal muscles. • Radiography: Thoracic radiographs can help rule out other causes of respiratory distress but are not diagnostic for laryngeal paralysis. Differential Diagnoses: • Myositis • Recurrent Laryngeal or Vagal Nerve Tumor • Inflammation • Myasthenia Gravis • Severe Hypothyroidism • Trauma • Generalized Neurologic Degeneration Treatment: • Medical Management: • Tranquilization: To reduce anxiety and respiratory effort in mild cases. • Corticosteroids: Administered to decrease laryngeal inflammation and edema. • Environmental Modification: Avoiding heat stress, excitement, and overexertion. • Surgical Intervention: Indicated in moderate to severe cases to enlarge the glottic opening and improve airflow. Techniques include: • Arytenoid Cartilage Lateralization (Tie-back Procedure): Suturing the arytenoid cartilage in an abducted position to prevent airway obstruction. • Ventriculocordectomy and Partial Arytenoidectomy: Removal of vocal fold tissue to widen the airway. • Castellated Laryngofissure: A surgical approach to access and modify the laryngeal cartilages. • Permanent Tracheostomy: Considered in severe cases or when other surgical interventions are contraindicated. Studies have demonstrated that bilateral ventriculocordectomy through a ventral median laryngotomy has had good long-term treatment success for idiopathic laryngeal paralysis in dogs. Unilateral arytenoid lateralization is also considered suitable for treating laryngeal paralysis in cats. Prognosis: With appropriate surgical intervention, many animals experience significant improvement in respiratory function and quality of life. However, potential complications include aspiration pneumonia, which necessitates careful postoperative monitoring and management. Understanding the clinical presentation, diagnostic approaches, and treatment options for laryngeal paralysis is essential for veterinary professionals to effectively manage this condition and improve patient outcomes.

Answer 143

Answer: **Gastrointestinal surgery** Explanation The correct answer is gastrointestinal surgery. Nitrous oxide moves into closed gas spaces such as the intestines. As such, its use is contraindicated in bowel surgeries. You should also be aware that nitrous oxide decreases tractional inspired oxygen levels although this can be managed and monitored in most instances. Nitrous oxide is contraindicated when pathology such as pulmonary bullae are present. - PowerLecture: Inhalant Anesthetics

Answer 144

Answer: **5-7 days** Answer Explanation The correct answer is 5-7 days. White blood cells have a circulating half life of 5-9 hours and red blood cells have an approximate life span of 110 days in dogs Note: The approximate life span of red blood cells in other species (in days) is as follows: cat-70, cow-160, horse-145, pig-86, sheep- 150

Answer 145

Answer: **The animal is hypovolemic** Explanation The correct answer is the animal is hypovolemic. CVP is a decent measure of circulating volume. A normal CVP can range from 0-10 cmH2O. It is important to interpret the CVP in light of your patient's clinical signs and to observe the trend in CVP measurements. [A Review of Central Venous Pressure and Its Reliability as a Hemodynamic Monitoring Tool in Veterinary Medicine](https://www.sciencedirect.com/science/article/abs/pii/S1938973616300277)

Answer 146

Answer: **Schirmer tear test** Explanation The correct answer is Schirmer tear test. A mucoid ocular discharge is the primary sign of keratoconjunctivitis sicca. A Schirmer tear test measures the amount of aqueous tear film being produced. In KCS, it should measure very low. The Fluorescein dye stain would check for disruption of the corneal layers such as a corneal ulcer. Tonometry would measure the intraocular pressure and look for diseases such as uveitis or glaucoma. The Fundic exam evaluates the retina and optic nerve for abnormalities. - PowerLecture: Keratoconjunctivitis Sicca - Keratoconjunctivitis sicca in the dog - PDF NAVLE prep file

Answer 147

Answer: **Color changes may occur seasonally** Explanation This is seasonal nasal hypopigmentation. Season associated lightening of the nasal planum occurs during winter months and can darken in the spring and summer. Complete depigmentation is not noted. Hypopigmentation and discoloration of the nose and mucocutaneous junctions can vary from benign immune-mediated diseases, such as vitiligo that lower the amount of melanocytes in the skin to seasonal variations in coloring, commonly called a "Dudley Nose" or "Snow Nose". Certain breeds are more predisposed than others, such as Siberian Huskies, Golden and Labrador Retrievers, and Bernese Mountain Dogs. This can be seen in any breed. With vitiligo, which is a benign immune related depigmentation, antimelanocyte antibodies can be found in circulation and a biopsy will show decreased melanocytes. Typically multiple areas will be affected, including ear tips, footpads, claws, and hair coat. Breeds predisposed to vitiligo can include German Shepherd Dogs, Collies, Rottweilers, Doberman Pinschers, and Giant Schnauzers There are no treatments to prevent these disorders, and they typically cause no harm to the animals.

Answer 148

Answer: **Normal response** Explanation The correct answer is normal response. Dark red vaginal discharge occurs normally for up to 6 weeks after whelping. Subinvolution can cause fresh bleeding for 12-15 weeks post-partum. Metritis is usually accompanied by systemic signs and may have abnormal vaginal discharge but not usually hemorrhage. Retained placentas typically do not occur in bitches. Pyometras occur during the luteal phase when progesterone levels are high, up to 9 weeks after estrus, and would not occur post-whelping.

Answer 149

Answer: **C6-T2** Explanation The correct answer is C6-T2. In a dog, the spinal cord is divided into the four regions listed above. Upper motor neuron signs include hyper-reflexia of spinal reflexes and increased muscle tone. Lower motor neuron signs include decreased or absent spinal reflexes and decreased muscle tone. A lesion between the C6-T2 spinal cord segments would result in lower motor neuron signs in the thoracic limbs and upper motor neuron signs in the pelvic limbs, as described in the patient in the question. A lesion between C1-C5 spinal cord segments would manifest as upper motor neuron signs in the thoracic and pelvic limbs. Lesions between T3-L3 spinal cord segments would not affect the thoracic limbs, but would manifest as upper motor neuron signs in the pelvic limbs. Lesions between L4-S3 spinal cord segments would result in normal thoracic limbs and lower motor neuron signs in the pelvic limbs. **PowerLecture: Spinal Cord Localization

Answer 150

Answer: **Salmon-poisoning disease** Explanation The correct answer is salmon-poisoning disease. In order to determine the correct diagnosis you need to put together several key pieces of information. The signalment gives you a heads up in that this dog is a sporting breed. The history practically gives away the answer when you put it together with the physical exam findings. The CBC and Chemistry results are not all that rewarding. The fecal sedimentation results should reinforce your suspicion that this is salmon poisoning. Remember, the dog eats the fish which had a fluke (Nanophyetus salmincola) which had Neorickettsia helminthoeca.

Answer 151

Answer: Explanation A bunny-hopping gait is most often seen in cases of hip dysplasia. Radiographs of the hips would be the next best step. Since there is no cranial drawer movement, there is not likely a CCL rupture. Panosteitis can be seen in younger dogs which are growing and would cause pain in the long bones. Typically lameness from rickettsial disease is painful and may affect multiple joints or limbs. ***PowerPage: Hip Dysplasia ***PowerLecture: Hip Dysplasia

Answer 152

Answer: **Proestrus and estrus** Explanation The correct answer is proestrus and estrus. During both of these phases, the female attracts males but she will only stand to be mated during estrus. ***PowerLecture: Estrous Cycle Part 1

Answer 153

Answer: **Complete blood count, coagulation panel, D-dimers** Explanation Cowboy's history and clinical signs are highly suggestive of disseminated intravascular coagulation (DIC). DIC cannot be diagnosed with just one test or pathognomonic clinical sign. It is important to look for thrombocytopenia, increased clotting times, and breakdown products of crosslinked fibrin via the D-dimer or FDP (fibrin degradation product) tests.

Answer 154

Answer: **Remove L-Asparaginase from the protocol** Explanation The signs described above are consistent with anaphylaxis, a potential side effect of treatment with L-asparaginase. Vincristine can also cause vomiting and diarrhea, but it usually takes a few days before they start, as opposed to within an hour of administration as seen with allergic reactions to L-asparaginase.

Answer 155

Answer: **Retina** Explanation The correct answer is *retina*. An ERG measures nerve impulses generated by the retina in response to a flash of light. Even if there is an abnormality in the optic nerve or brain, if the retina is functioning normally, the ERG will be normal. Even with preetinal lesions such as a complete cataract or corneal edema, enough light is transmitted through to the retina to yield a response. **Electroretinogram** In dogs, as in most other animal species, subjective assessment of retinal function is difficult even for the experienced clinician. Thus, for more than a century, recording of electrical currents driven by the photoreceptors in response to light stimuli has been used to objectively assess retinal function in the dog [1]. The full-field, flash electroretinogram (ERG) is now a well-established test of canine retinal function for the clinical diagnosis of hereditary retinal dystrophies and other causes of retinal degeneration. ERG is also used to assess retinal function in patients with opaque media and rule out generalized retinal diseases in patients with sudden loss of vision.

Answer 156

Answer: **Omega-3 fatty acids** Explanation Consuming a high concentration of omega-3 fatty acids (eicosapentaenoic acid and docosahexaenoic acid) has been shown to result in the preferential use of these compounds to form eicosanoids. Eicosanoids derive from either omega-3 or omega-6 fatty acids. Omega-6 eicosanoids are generally pro-inflammatory, while omega-3 eicosanoids are less inflammatory. Omega-3 fatty acid supplementation results in a decrease in pro-inflammatory omega-6 eicosanoids; providing potential benefit to patients with osteoarthritis. Carnitine is thought to potentially aid in weight loss as it is involved in fat metabolism, but there are limited studies demonstrating significant clinical benefit to supplementation at this time. Glucosamine is a precursor of glycosaminoglycans which is a major constituent of the joint and thought to be of great importance for joint health. Chondroitin is also an important constituent of cartilage and helps provide resistance to compressive force. It is commonly administered in conjunction with glucosamine. The amount of clinical benefit of glucosamine and chondroitin supplementation is not currently well established.

Answer 157

Answer: **Transmissible venereal tumor** Explanation The correct answer is transmissible venereal tumor. This tumor contains 59 chromosomes in contrast to dogs, which have 78.

Answer 158

Answer: **Thoracic radiographs and fungal serology** Explanation Osteolytic lesions along the distal femur are highly suspicious of osteosarcoma (OSA). Given the age and clinical history it should be your first differential. The other differential would be fungal disease such as coccidioidomycosis (Valley Fever). This fungal infection is seen predominantly in the southwestern United States, but should not be excluded without full testing. The appropriate next step to differentiate OSA from Valley Fever would be thoracic radiographs to look for metastases and fungal serology to determine exposure and antibody levels to fungal diseases. Chest films are available for review below which show metastatic disease. Of note, coccidioidomycosis can also affect the lungs, leading to an interstitial, bronchiolar, multifocal, or alveolar pattern as well. Gold standards for diagnosis of OSA are biopsy of the affected boney lesion. Remember OSA should not cross the joint. Elevations in alkaline phosphatase and/or gross visible metastatic lesions give a worse prognosis with shorter longevity, even with aggressive treatments. [Clinical clinicopathologic and radiographic findings in dogs with coccidioidomycosis](https://avmajournals.avma.org/downloadpdf/view/journals/javma/222/4/javma.2003.222.461.pdf)

Answer 159

Answer: **3-6 months** Explanation The correct answer is 3-6 months. However, in dog populations where vaccination is poorly practiced, all dogs may be affected. Before 3 months, puppies are most likely protected through maternal antibodies. CDV is very contagious and spread mainly via aerosolized respiratory secretions. The virus is shed for several weeks after infection.

Answer 160

Answer: **SNAP Parvo test** Explanation The most appropriate next step in diagnosis would be a parvovirus test. Even though the puppy is vaccinated for parvovirus, the puppy's age can contribute to incomplete vaccination. The puppy also has been to a dog park recently, so would be at a higher exposure risk. Direct fecal smear could lead to a diagnosis of parasitic or protozoal diseases, but the puppy's symptoms are more acute and severe than is typical for those diseases. The symptoms and history are also typical of pancreatitis (PLI) and upper Gl obstruction (barium study and ultrasound), and those should be explored once parvovirus is ruled out.

Answer 161

Answer: **Lymph node aspirates and thoracic radiographs** Explanation Malignant melanoma is the most common malignant oral tumor in dogs. Melanoma is highly metastatic, so further treatment is indicated. Additionally, thoracic radiographs and regional lymph node aspirates should be performed to identify metastases before radical treatment is initiated. A second surgery may or may not be required, depending on the margins obtained, but staging is needed first. Radiation therapy is generally preferred over chemotherapy for melanoma, but treatment protocols depend on the patient and the tumor location. The melanoma vaccine is recommended for every patient, but should be administered only after staging results are obtained.

Answer 162

Answer: **Immune-mediated hemolytic anemia. Administer a packed red blood cell transfusion, prednisone, and cyclosporine.** Explanation This signalment is classic for IMHA, and cocker spaniels are the only known breed to be genetically predisposed to IMHA. The clinical signs are also typical for IMHA but the key to answering this question is the bloodwork. IMHA typically has a normocytic normochromic regenerative anemia and the classic findings seen are autoagglutination and spherocytes. The only abnormal finding commonly seen on a chemistry panel with this disease is a mild to moderate bilirubinemia due to red blood cell hemolysis. The treatment for IMHA is immunosuppressive therapy (prednisone and cyclosporine). A blood transfusion may be indicated if the PCV is very low (usually less than 20%) or if the patient is showing clinical signs for their anemia. Packed red blood cells would be indicated in this case over a whole blood transfusion because it would provide a higher number of red blood cells and maximize the PCV. Vincristine is a drug administered in an emergency situation for immune-mediated thrombocytopenia to increase the function of functional platelets.

Answer 163

Answer: **Immune-mediated** Explanation In canine patients, the most common cause of KCS is immune-mediated. This is why these patients are treated with cyclosporine, a t-cell modulator. Penicillin has not been documented to result in KCS, although sulfonamide-containing antibiotics, such as trimethoprim-sulfa, have been shown to cause KCS in some patients. Long-term atropine administration has also been shown to result in KCS. Atropine is a parasympatholytic and will result in decreased tear production. Etodolac has also been associated with KCS in dogs. While food allergy may cause ocular itching or irritation, it doesn't typically cause dry eye. Early spay or neuter has not been shown to cause KCS. The corneal pigmentation seen with this condition is a nonspecific response to chronic irritation or inflammation. There is also evidence of corneal vascularization, which occurs as part of the inflammatory and healing response. ***PowerLecture: Keratoconjunctivitis Sicca

Answer 164

Answer: **The dog is infected with a tapeworm species that is not susceptible to fenbendazole** Explanation The best answer to this question is the dog is infected with a tapeworm species that is not susceptible to fenbendazole. While fenbendazole is effective against Taenia species, it has no activity against the more common tapeworm, *Dipylidium caninum*, which requires **praziquantel for treatment**. The history and the owner's diligence make the likelihood that the dog is still encountering fleas and being reinfected with tapeworms very low. There is no known emergence of resistance to fenbendazole in formerly susceptible tapeworm species, and there is no other currently known canine parasite that presents with the classic "grain of rice" description.

Answer 165

Answer: **Bernese Mountain Dogs** Explanation The correct answer is Bernese Mountain Dogs. These dogs are by far, the most overrepresented breed for developing histiocytic neoplasia.

Answer 166

Answer: **Immune-mediated hemolytic anemia** Explanation The correct answer is immune-mediated hemolytic anemia. Pulmonary thromboembolism is the most common site for thromboembolic disease. In this patient, the thrombus is likely lodged at the iliac bifurcation, causing obstruction of blood flow distal to the site of impaction. Hyperadrenocorticism (not hypoadrenocorticism) can cause a hypercoagulable state and increase risk for a thromboembolism. There has been no association between idiopathic epilepsy and increased risk of thromboembolism. Wobbler syndrome is cervical spondylomyelopathy, a disease of the cervical spine (mostly in large-breed dogs) causing spinal cord or nerve root compression, neck pain, and neurologic symptoms.

Answer 167

Answer: **Hyperkalemia and whipworm infection** Explanation The fecal flotation shows whipworm eggs. Whipworm infection is a cause of hyperkalemia (elevated potassium), which causes bradycardia. Hypothermia, hyperkalemia, A-V conduction blocks, and high vagal tone can all lead to bradycardia. Whipworm infection and hypoadrenocorticism (Addison's disease) are two causes of elevated potassium levels. You may also wish to perform an ACTH stimulation test in this dog to rule out concurrent hypoadrenocorticism.

Answer 168

Answer: **Medial** Explanation The correct answer is medial. Luxating patellas in both small and large breed dogs occur more commonly to the medial side. Some large breed dogs will luxate laterally but not as frequently as to the medial side. Small breed dogs rarely have luxating patellas to the lateral side. ***PowerLecture: Patellar Luxation

Answer 169

Answer: **Bartonella sp** Explanation The correct answer is Bartonella sp. The most commonly reported organisms recovered in animals with endocarditis include Staphylococcus aureus, Streptococcus sp., Corynebacterium sp., Pseudomonas aeruginosa, Erysipelothrix, E. coli, and Bartonella sp.

Dogs II Flashcards

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