Cats and dogs 15 Flashcards
What to do with a sick dog chronic vomiting with albumin <20g/L
○ Start with all 3 -> immune suppression, modify microbiome, diet
§ BUT NOT FMT or probiotics in a sick dog
§ May need a supportive diet at the start
○ Taper off according to dog
§ 1. antibiotics, 2. immune suppression 3. diet
What approach for chronic SI diarrhea in a cat
- SAME AS FOR VOMITING
- Rule out metabolic disease, out on diet trial
- Diagnosis
○ Ultrasound
○ Biopsy of gut
○ Vitamin B12
Usually need lifelong immune suppression - prednisolone
What is the role of the LI
- Physiological barrier (mucus)
- Large commensal bacterial population:
○ Produce short chain fatty acids (SCFA)
○ Contributes up to 10% energy requirements
○ Dogs majority anaerobes, cats 50%
○ If not well developed flora excess sugars not metabolised to SCFA and results in osmotic diarrhoea - MAJOR WATER RESERVOIR
- NO DIGESTIVE ROLE
What are the main signs of LI disease
- Mucoid faeces
- Haematochezia (fresh blood)
- Tenesmus (straining to defecate
- Dyschezia (pain on defecation)
- Very occasionally weight loss/vomiting
- Constipation
Rectal prolapse/perineal swelling
Differentials for colitis what main in australia, mainly causing haematochezia, really sick
COMMON IN AUS - Fibre-responsive (idiopathic) - IBD - ○ Lymphocytic-plasmacytic ○ Histiocytic ulcerative (granulomatous) colitis in boxers - C perfingens overgrowth - Trichuris vulpis (whipworm) - cat HAEMATOCHEZIA - Neoplasia ○ Lymphoma ○ Adenocarcinoma REALLY SICK - Uraemic colitis - Pancreatitis
What is the clinical approach to LI diarrhoea in dogs
- Initially must:
○ Establish whether any signs of weight loss, systemic illness or signs of diffuse diarrhoea
○ Do a thorough rectal examination - 360 degree examination - If animal is well, a breed other than boxer and no palpable rectal abnormality - non-specific treatment trial
- Investigate if
○ A boxer or French bulldog
○ Weight loss
○ Diffuse diarrhoea
○ Systemically unwell
What are the 2 main things within non-specific treatment trial in LI diarrhoea for dogs and what should do with different results
Non-specific treatment trial
- Faecal analysis OR fenbendazole 50mg/kg sid 5 days - FOR WHIPWORM
- Fibre supplementation
○ Add Psyllium (soluble) OR low-residue diet
Result
- If good response taper/discontinue fibre or diet if desired after 2-3 months
- If poor response or SICK dog then investigate further
a. Faecal analysis
b. Metabolic screening
c. Biopsy
Biopsy of LI in dogs what are the 2 ways and compare
- Full-thickness biopsies inherently risky in diseased colon
1. Colonoscopy: required preparation, can exam the entire LI and ileo-colic valve
2. Proctoscopy: rigid scope -> only seeing descending colon -> enema and 24 hours of fasting only - Colonoscopy vs proctoscopy
○ Most LI conditions can be diagnosed with rigid proctoscopy except:
§ Occult trichyriasis, ileocolic or caecocolic intussusception, typhlitis or neoplasia that is localised to the transverse or ascending colon
○ The main complication of colonoscopy -> perforation of the colon
§ Can occur upon introduction of the instrument, when the colon is insufflate with air, or when biopsies are taken
Biopsy of LI in dogs what preparation is needed for colonscopy
○ Fast for 24 hours
○ Go lytely (osmotic cathartic solution)
§ Stomach tube 3 doses of 33mL/kg minimum 3-4 hours apart
§ Naso-oesophageal tube 100mL/kg over 6-8 hours
○ Warm water enemas
§ Evening before and morning of (not within 2 hours)
Cats with LI disease what is less common than in dogs and what is the order of investigation
- Idiopathic disease and clostridial overgrowth LESS COMMON than in dogs
- Investigation is recommended in following order:
○ Faecal analysis - for Trichuris
○ Trial treatment with fenbendazole and diet
○ Metabolic screening (including T4, FeLV, FIV)
○ Ultrasound - higher possibly for lymphoma
○ Colonic biopsies if no response to treatment after initial work-up
List the 3 main types of colitis
- L-P (lymphocytic-plasmacytic) colitis
- Clostridial growth (dysbiosis - of clostridia)
- Granulomatous (histiocytic ulcerative colitis)
L-P (lymphocytic-plasmacytic) colitis what may also have, diagnosis and treatment
○ May have concurrent upper GI sins (may be clinically silent)
○ Biopsy confirmation
○ Try hypoallergenic diet and fibre first then
§ Immunosuppression 6-8 weeks if moderate signs
○ Sulfasalazine (or derviateives) if only LI disease - SIDE EFFECTs
Clostridial growth (dysbiosis) how generally occur, diagnosis and treatment
○ Often stress triggered -> generally dysbiosis then causes stress -> goes back to cycle
○ Difficult to diagnose - spores in healthy dogs
○ Treat with fibre
○ Antimicrobials not necessary unless very poor response or concerned about translocation
Granulomatous (histiocytic ulcerative colitis) what does it lead to, breed mainly wihtin and presentation
○ Form of colitis with severe mucosal ulceration
○ Predominantly affects boxer dogs, although has been reported in other breeds
Presentation
§ Usually young (<2 yo) at presentation
§ Severe clinical signs
□ Profound haematochezia
□ Often weight loss and poor growth - KNOW IS SEVERE AS NOT COMMON IN LI
§ Also french bulldogs
Granulomatous (histiocytic ulcerative colitis) diagnosis and prognosis with what treatment
○ Diagnosis - Endoscopically severe ulceration - Histologically a mucosal infiltrate of plasma cells, lymphocytes and PAS-positive macrophages □ Severe mucosal ulceration □ Patchy distribution - Culture for E. coli - IF SUSCEPT THEN CALL C. MANSIFELD ○ Prognosis - Several reports of cures with enrofloxacin □ 8 weeks at 5mg/kg sid □ Long-term remission (>4.5 years) □ Genetic defect in bacterial killing of E.coli - destroy bacteria with antibiotics
Tritrichomonas foetus what species within, how prevalent and where mainly found
CATS - World-wide distribution in cats ○ Australia does not have as high prevalence as US or Europe - Mainly cat breeders and shelters ○ Bengals pre-disposed ○ Up to 30%
Tritrichomonas foetus clinical signs
○ Colitis when increased frequency of defaecation
○ The anus may become inflamed and painful, +/- faecal incontinence
○ Majority under 12 months of age
Most affected cats are otherwise well, and show significant weight loss
Tritrichomonas foetus diagnosis and prognosis
- Diagnosis
○ Looking for moving parasites in fresh faecal smears - positive 5/36 cats (not very sensitive)
○ Using a specific culture system -> positive 20/36 cats
○ Be detection of T-foetus DNA using PCR - positive 34/36 cats
○ Faecal sample - should get deep sample not voided - Place tube within rectum with syringe -> sedation
- Prognosis
○ Some cats will recover spontaneously by 2 years of age
○ However, many will have very severe clinical signs
Tritrichomonas foetus treatment
○ Resistant to fenbendazole ○ Ronidazole more effective - Some neurological side effects - is treatment worse than disease - Not licensed for use in cats - Bitter taste (so put in capsules) - 30mg/kg sid 2 weeks - Decrease dose in young cats
Irritable bowel syndrome how defined, what pets, characterised by
- Poorly defined disease ○ Altered bowl motility ○ Visceral hypersensitivity ○ Psychosocial factors ○ Neurotransmitter imbalance ○ Mucosal inflammatory cytokine - Pocket puppies - Is it a real disease or symptomatic issues - Characterised by diarrhoea (usually LI) vomiting and abdominal cramping
Irritable bowel syndrome diagnosis and treatment
- Diagnosis of exclusion
○ Main DDx is IBD with associated pain - Treatment
○ Empirical treatment with anti-cholinergic and fibre supplementation
§ NB careful with altering motility without histology
○ Reduce stresses
if mainly Haematochezia what should do and main differentials
- Main differentials if eliminate metabolic disease, infectious disease (parvovirus, HE) and colitis
○ Rectal adenocarcinoma
○ Rectal polyp
○ INCREASE INDEX OF SUSPESSION
Adenocarcinoma in LI what can result in, diagnosis and treatment
- Infiltrative and cause narrowing of rectum so often also tenesmus
○ Metastasise to Sub-lumbar lymph nodes can be huge and then lead to tenesmus - Diagnose on rectal examination most of the time, may need biopsy and proctoscopy
- Older dogs
- Surgery ideal
- Piroxicam for palliation
Polyps in LI does it cause obstruction, when diagnosis, treatment and prognosis
- Rarely cause obstruction
- Usually pedunculated on rectal exam
- Solitary or multiple
- Need good sample size for confirmation with histology
- Surgical excision or anti-inflammatories if indicated
- Good prognosis
What is animal present with dyschezia/tenesmus what does that indicate and differentials
- OBSTRUCTION TO DEFECATION
- Perineal fistulae
- Prostatic disease
- Pelvic fractures
- Perineal hernias
- Perianal gland tumours
- AG tumours
- Abscess (cat)
- Constipation
Rectal stricture
Anal sacculitis what occurs, general presentation, what needed and treatment
- Anal sac becomes infected (may cause cellulitis)
- Older, small dogs
- Very painful
○ Sedation or GA often required to examine adequately - Treatment
○ Expression
○ Lavage with saline and instil antibiotic solution
○ Higher fibre food to increase defecation and therefore expression
○ Removal if recurrent NOT IF RUPTURED
Anal sac adenocarcinoma what sex, what associated with, diagnosis, treatment and prognosis
- Older females
- Associated with paraneoplastic hypercalcaemia - PU/PD - generally why present no the LI signs
- Need careful rectal palpation
- Assess SL lymph nodes
- Surgical excision (+/- palliative chemo)
- Guarded prognosis
What is animal present with straining and no result what indicate and differentials
CONSTIPATION AND OBSTIPATION - Differential as for tenesmus/dyschezia as well as: ○ Poor colonic motility § Idiopathic megacolon § Systemic disease (low K, Ca, low T4) § Neuromuscular disease high ○ Obstruction ○ Dehydration ○ Dietary (especially bones) ○ Drug-induced
If animal present with straining without result what is the diagnostic approach
- Evaluate for systemic signs and any rectal/perineal disease
- IV fluids if dehydrated
- Abdominal radiographs (pelvic #)
- Evacuation of faeces (enema)
- +/- ultrasound or barium enema
- +/- proctoscopy
Enema when use and how done
colitis, impaction
- Use lukewarm water
- Don’t use hypertonic enemas if bone impaction
- Break down impacted faeces with sponge forceps or hose attachment
- GENTLY - can take hours
Idiopathic megacolon what is it a major cause of, why occurs, differentials and diagnosis
- Major cause of constipation in cats
- Smooth muscle functional defect
- Rule out pelvic stenosis, neurological disease, neoplasia and metabolic disease
- Abdominal radiographs essential
What is the normal radiographic appearance of the oesophagus and what is needed for investigation
NORMALLY - cannot see it because it is collapsed and is of the same opacity as the soft tissue within the cervical region and mediastinum
Examinations using contrast media are usually necessary to investigate suspected oesophageal disorders
How to use and which contrast use for contrast studies of oesophagus
- Radiographs must be taken prior to any contrast study
- Positive contrast used in evaluation of oesophageal lesions and motility disorders
- Dynamic fluoroscopic examination is usually necessary to evaluate functional abnormalities
- Barium used to evaluate the mucosa and lumen and can be mixed with food
- Risk of aspiration -> small volume barium is usually benign but should be still be avoided
- Use non-ionic iodinated contrast medium
○ Swallowing disorders -> best evaluated fluoroscopically as dynamic diseases
megaoesophagus radiographic appearance and what can look like this
Air within the oesophagus gives contrast (able to see soft tissue opacity of the walls of oesophagus)
- Dogs when stressed may swallow air see focal area of air within (will not be focal like this)
Tracheooesophageal strip sign what used for and what see when present
Helps determine whether air within oesophagus
- NORMALLY DON’T SEE DORSAL ASPECT OF THE DORSAL WALL OF TRACHEA
- Seeing Dorsal wall of trachea (ventral and dorsal aspect of this wall)
Megaoesophagus what does it indicate and causes
- Indicates enlargement of oesophagus which may be segmental or generalised, congenital, hereditary or acquired
○ Acquired -> neuromuscular, endocrine, inflammatory or obstructive disorders
○ Most idiopathic
○ May occur cranial to obstruction or associated with oesophagitis
Oesophageal strictures when occur and possible radiographic finding
- Stricture formation may occur with deep oesophageal due to oesophagitis, neoplasia, trauma, FB
- Oesophagus often normal on survey radiograph
- Dilation of the oesophagus proximal to the stricture is an inconsistent finding
What are the 3 further imaging tests for the oesophagus
- Fluoroscopy: Dynamic evaluation of swallowing and oesophageal motility with fluoroscopy important in mild, intermittent or segmental disease.
- Ultrasound: Wall layering, relationship to other cervical and abdominal organs
- Cross-sectional Imaging - (Computed Tomography, Magnetic Resonance Imaging): Relationship with other organs
assessing the stomach radiographically what is important to assess and what is normal
- Assess size ○ No greater than 3 intercostal spaces wide ○ Fundus typically 2 x wide as pylorus - Contents - ideally fasted 12-24 hours before exam - Position ○ Cranial to 12thrib ○ Axis should be parallel to the ribs - Is this a surgical abdomen?
what causes a displacement of gastric silouette caudally and cranially and contrast studies within stomach, what indicate and timing
Displacement of the gastric silhouette caudally -> hepatic enlargement
Displacement cranially -> reduction in size of liver
Contrast studies
- Will indicate delayed gastric emptying
○ Normal stomach empty within 1-4 hours after barium administration
○ Retention within 3-4 hours after indicates pyloric obstructive disease
- Fluoroscopy assessment best way to diagnose pyloric obstructive disease
