Week 6 Flashcards

Question

What happens in a CN 3 palsy?

Answer 1

1. Pathogenesis: compressive aneursym arising from junction of ipsilateral **posterior communicationg artery** w/ **internal** **carotid** **artery**; **periphery** of nerve has **autonomic** function (**visceral** efferent fibers) that mediate pupillary light and near-reflex pathways Presentation: **dilated** pupil, diminished or absent pupillary light reflex/loss of accommodation, **"blown pupil"**, "down and out gaze" (**ptosis and diplopia**) **_later_** on; 2. Pathogenesis: **ischemia**, uncal herniation, **posterior cerebral artery aneurysm**, **vascular disease** (DM/ diabetic ophthalmoplegia); Interior portion of nerve has **somatic** efferent fibers that innervate CN3 controlled **muscles** of the eye Presentation: normal sized, reactive pupil, **down and out pupil**, **ptosis**

Answer 2

It is produced by N. meningitidis and N. gonorrhoeae, S. pneumoniae, and H. influenza. The enzyme **cleaves** secretory IgA at its **_hinge region_**, rendering it ineffective. This facilitates **bacterial adherence to mucosa**. Secretory IgA exists on **mucosal** surfaces and in secretions and acts to bind and inhibit the action of pili as well as other surface antigens that normally mediate mucosal adherence and subsequent penetration.

Answer 3

Presentation: irregulary shaped adherent breast mass; **upper** **outer** quadrants of the breast are the most common site of breast cancer; overlying skin retractions (e.g., dimpling) signal involvement of **suspensory ligaments** of the breast (e.g., **Cooper ligament**); malignant infiltration of these ligaments causes **fibrosis** and **shortening**, leading to **traction** on the skin w/ distortion in breast contour **Inflammatory breast carcinoma**: direct invasion of dermis; skin changes w/ erythema, and invasion of **lymphatic** spaces w/ malignant cells leads to **lymphedema** w/ finely pitted appearance known as **peau d'orange**

Answer 4

1. **The LV is perfused only during diastole**: contraction during systole leads to compression of coronary vessels and disruption of blood flow; wall tension highest near endocardium making **subendocardial** region prone to ischemia 2. **Myocardial O2 extraction is very high:** extracts 60-75% of O2 from blood; as a result, cardiac venous blood in **coronary sinus** (before reaching LA and mixing w/ blood returning from systemic circulation) is the **most** **deoxygenated** **blood** in the **body** 3. **Myocardial O2 demand and coronary blood flow are tightly coupled**: little capacity to increase myocardial O2 extraction during periods of increase O2 demand b/c it is already high at rest, so the only way to increase O2 delivery to heart is to increase coronary blood flow (adenosine and nitric oxide are important vasodilators responsible for increasing coronary blood flow)

Answer 5

1. middle **ear** cavity, eustachian tube, mastoid air cells 2. epithelial lining of palatine **tonsil** 3. dorsal wings: left and right **inferior parathyroids**; ventral wings: **thymus** 4. dorsal wings: **superior parathyroids**; ventral wings: ultimobranchial body, parafollicular cells of thyroid [Ear tonsil bottom to top]

Answer 6

Genital tubercle: glans clitoris, vestibular **bulbs** Urogenital **sinus**: greater vestibular **glands** (of **Bartholin**), urethral and paraurethral **glands** (of **Skene**) Urogenital folds: labia minora Labioscrotal **swelling**: labia **majora**

Answer 7

Genital tubercle: glans penis, corpus **cavernosum** ad **spongiosum** Urogenital sinus: bulbourethral **glands** (of **Cowper**), **prostate** gland Urogential folds: ventral **shaft** of penis (**penile** **urethra**) Labioscrotal swelling: **scrotum**

Answer 8

**Parents Start Observing** **Primitive** reflexes disappear; **Posture** - lifts head up prone, rolls and sits, crawls, stands, walks; **Picks** - passes toys hand to hand, **Pincer** grasp; **Points** to objects **Social** smile, **stranger** anxiety, **separation** anxiety **Orients** - first to **voice**, then to **name** and gestures; **Object** permanence; **Oratory** - says "mama" and "dada"

Answer 9

**Don't Forget, they're still Learning!** **Drive**-tricyle (3 wheels at 3y; **gross** **motor**); **Drawings** - copies lines or circle (**fine** **motor**), stick figure; **Dexterity** - **hops** on one foot, uses buttons or zippers, grooms self **Freedom** - comfortably spends part of day away from mother; **Friends** - play in **parallel** but **not** **cooperatively** w/ others, has **imaginary** friends Language - **1000** words by age 3 (3 zeros), uses complete sentences and prepositions; Legends: can tell **detailed** stories; can **describe** their age and gender

Answer 10

Pathogenesis: structural **brain** **injury** (e.g., stroke, tumor, head trauma), infection, metabolic abnormalities (e.g., hypoglycemia) and medication noncompliance in individuals w/ known epilsepy Presentation: A single seizure lasting greater than 5 minutes or the occurrence of multiple discrete seizures with **incomplete** **recovery** of **consciousness** **between** **episodes**. Tx: **IV lorazepam** and **phenytoin** given concurrently to prevent **recurrence** of seizure activity Phenytoin: long acting anticonvulsant that inhibits neuronal high-frequency firing by reducing the ability of Na channels to recover from inactivation

Answer 11

Pathogenesis: Defect in interatrial septum; **ostium secundum** defects most common and usually an isolated finding Presentation: wide, fixed splitting of S2, may lead to **paradoxical** **emboli** (systemic venous emboli use ASD to bypass lungs and become systemic arterial emboli); hemoydnamically significant ASD can produce chronic **pulmonary** **HTN** as a result of left to right shunting Eisenmenger syndrome is the late-onset reversal of left to right shunt due to pulmonary vascular sclerosis resulting from chronic pulmonary HTN. Closure of ASD required to prevent **irreversible** **pulmonary** **vascular** **sclerosis** and a **permanent** **Eisenmenger** syndrome.

Answer 12

Pathogenesis: aspirin administered to child w/ febrile illness (URI infection, influenza, measles, varicella or another **viral** disease); inborne metabolic error that renders children sensitive to toxic effects of salicylates Presentation: **hepatic failure** (vomiting, hepatomegaly); **encephalopathy** due to hepatic dysfunction and toxic effect of **hyperammonia** on CNS leading to **cerebral edema** Histology: liver - **microvesicular steatosis** (small fat **vacuoles** in cytoplasm); **no necrosis or inflammation**; **swelling**, **decreased** number of **mitochondria** and **glycogen** **depletion**

Answer 13

Pathogenesis: causative organism - aspergillus fumigatus, causes significant infection in immunocompromised or debilitated patients; colonized the bronchial mucosa Presentation: pts w/ **asthma** or **CF** develop an allergic hypersensitivity reaction to the fungus; intense airway inflammation and mucus plugging w/ exaceration and remissions; repeated exaceration may produce transient **pulmonary** **infiltrates** and proximal **bronchiectasis** Dx and Labs: high serum **IgE levels**, **eosinophilia**, and **IgE plus IgG serum** antibodies to Aspergillus

Answer 14

Pathogenesis: tears occur secondary to rapid increase of **intraabdominal** and **intraluminal** **gastric** **pressure**, during retching and vomiting Presentation: alcoholics; asymptomatic or can lead to GI hemorrhage that manifests as hematemesis Risk factors: hiatal hernias Histology: longitudinal mucosal tears at esophagogastric-squamocolumnar junction

Answer 15

Pathogenesis: commonly due to a direct blow to anterior aspect of the knee (e.g., fall, motor vehicle accident); indirectly - excessive force transmitted throiugh quadriceps tendon (e.g., landing on feet after falling from a height) Presentation: acute swelling, tenderness, **inability to extend** knee against gravity, **palpable** **gap** in the extensor mechanism; pts w/ intact medial and lateral retinaculum may have partially spared knee extension

Answer 16

****_Holo_**crine**: cell **lysis** releases entire contents of the cytoplasm and cell membrane; ex: **sebaceous** glands, **meibomian** glands of the eyelid **Merocrine**: cells secrete **_watery_** secretory product via exocytosis w/ **no loss of cell membrane** (mero maintains membrane); ex: **salivary** glands, **eccrine** **sweat** glands, **aprocrine** **sweat** glands **Apocrine**: cells secrete **_secetory_** product via **_membrane-bound_** vesicles; **mammary** glands

Answer 17

Pathogenesis: Keratinization of hair follicle w/ formation of keratin plug that blocks release of sebum, hypertrophy of sebaceous glands w/ excess sebum production, colonization of glands w/ **propionibacterium** acnes, bacterial hydrolysis of triglycerides in sebum and release of **inflammatory** **fatty** **acids**

Answer 18

Presence of LV systolic dysfunction due to reduced coronary blood flow at rest that is partially or completely **reversible** by coronary **revascularization**. A state of **chronic myocardial ischemia** in which both myocardial metabolism and functioni are **reduced** to match a concomitant reduction in coronary blood flow (due to moderate/severe flow-limiting stenosis) New equilibriuim **prevents myocardial necrosis**. Demonstrates decreased expression and disorganization of contractile and cytoskeletal proteins, altered adrenergic control, and reduced Ca2+ responsiveness. Coronary **revascularization** and subsequent **restoration** of blood flow to hibernation myocardium improves **contractility** and **LV function**.

Answer 19

Etiology: overdose, volume depletion (decreased GFR), drug interactions (thiazide diuretics, NSAIDs (not aspirin), ACE inhibitors, tetracyclines, metronidazole Presentation: **acute** **toxicity** (GI - N/v/d, late neurologic sequelae); **chronic** **toxicity** (neurologic): confusion, agitation, ataxia, **tremors**/**fasciculations** Mgmt: hemodialysis for severe cases

Answer 20

The most common pediatric malignancy. Pathogenesis: neoplastic cells of ALL arise from lymphocytic precursors of the pre-B or pre-T lineage (**blast** cells) Presentation: fever, fatigue, **pallor**, **petechiae**, bleeding; spread can cause **lymphadenopathy**, **hepatosplenomegaly**, and **bone** **pain** Presentation of T cell ALL: male in late childhood/young adulthood; large anterior **mediastinal** **mass** that can compress the great vessels, causing SVC syndrome; compression of esophagus causing **dysphagia**; compression of trachea causing **dyspnea** and **stridor** Markers: T cell (**TdT**, CD2-8), B cell (**TdT**, **CD10**, **19**, **20**) Blood smear: **blast** cells

Answer 21

Second most common cause of **ring**-**enhancing** lesions w/ mass effect in HIV. Pathogenesis: diffuse, large cell non-hodgkin lymphoma of **B cell origin** that usually occurs as a late complication of HIV infection; **EBV** is identified in almost all cases Presentation: pt w/ HIV and mutliple **ring**-**enhancing** lesions being treated empirically for toxoplasmosis, lack of clinical or imaging response after 1-3w of therapy; **negative** Toxo serology Histology: classically, large, solitary lesions; T cell infiltration **_not seen_** Dx: positive EBV pcr analysis in CSF; definitive dx requires **brain** **biopsy**

Answer 22

**Erythropoietin**, **darbepoetin** **alpha**; can be used to treat anemia of chronic kidney disease Improve anemia, avoiding the need for blood transfusions in CKD and dialysis patients SEs: associated w/ increased risk for **thromboembolic** **events** (e.g., vascular graft **thrombosis**, **stroke**) due to increased blood **viscosity**, as a result of the elevation in red cell mass; **hypertension** due to activation of EPO receptors on **vascular** **endothelial** and **smooth** **muscle** **cells**

Answer 23

Alanine Methionine Histadine Valine [**Alan** **met** **his** **val**entine.]

Answer 24

A rare form of **marrow** **failure** characterized by severe hypoplasia of marrow erythroid elements in the setting of **normal** granulopoiesis and thrombopoiesis. Pathogenesis: inhibitioni of erythropoietic precursors and progenitors by **IgG** **autoantibodies** or **cytotoxic T lymphocytes**; assoc. w. immune system diseases such as **thymomas** and **lymphocytic** **leukemias**; **parvovirus B19** infection (preferential destruction of proerythroblasts) Presentation: young patient; **pallor**, **fatigue**, **anemia** Labs: low RBC count, low percentage of reticulocytes (decreased RBC production) and low hemoglobin; WBC, platelet count, and bone marrow precursors are **normal** Dx: chest CT scan if **thymoma** is suspected; parvovirus infection: detection of **anti**-**B19** **IgM** **antibodies** in serum Tx: when **thymoma** is present, its removal can **cure** pure red cell aplasia

Answer 25

Pathogenesis: **autodigestion** of pancreas by pancreatic enzymes; high levels of circulating TGs lead to increased production of FFA w/in pancreatic capillaries by pancreatic lipase leading to **direct** **injury** to pancreatic acinar cells [TGs cause direct **tissue** **toxicity**] Causes: Idiopathic, **Gallstones\***, **Alcohol\***, Trauma, Steroids, Mumps, Autoimmune disease, Scorpion sting, Hypercalcemia/Hypertriglyceridemia (**\>1000mg/dL**), ERCP, Drugs (sulfa drugs, NRTIs, protease inhibitors) [I GET SMASHED] \*most common Presentation: middle-aged, older adults, women; acute epigastric pain radiating to **back** Labs: if due to alcohol in the **absence** of **gallstones**, AST:ALT ration greater than 2, **macrocytosis** related to poor nutrition (folate deficiency), liver disease and/or direct toxicity of alcohol on the marrow, can occur independently of folate deficiency Dx: increase serum amylase, **lipase** (more specific) Complications: **pseudocyst**, a collection of fluid rich enzymes and inflammatory debris; walls consist of **granulation** **tissue** and **fibrosis**, **_no epithelial lining_** [true cysts: lined by epithelium]

Answer 26

It counteracts alveolar collapse by **decreasing** **surface** **tension** as the alveolar radius decreases. As the inside area of the sphere decreases, surfactant becomes more concentrated and thus is able to **decrease** surface tension to a greater extent. As sphere grows larger, surfactant molecules become more spread out and do not reduce surface tension as much.

Answer 27

Pathogenesis: occurs when tumors w/ high cell turnover are treated w/ chemotherapy; lysis of cells causes intracellular ions, such as K and P and uric acid (metabolite of tumor nucleic acid) to be released into serum Uric acid is soluble at physiolgic pH, but can **precipitate** in normally **acidic** environment. Lowest (**acidic**) pH of nephron is found in **_distal tubules_** and _**collecting** **ducts**_. Prevention of TLS: urine alkalinization and hydration; high urine flow and high pH along nephron prevents crystallization and precipitationi of uric acid

Answer 28

A chest tube for drainage of pleural effusion is placed through the skin and subcutaneous fat into the **4th or 5th** intercostal space in the anterior axillary or **midaxillary** **line**. The tube traverse through the **serratus** **anterior** **muscle**, **intercostal** **muscles**, and **parietal** **pleura**.

Answer 29

Pathogenesis: Salmonella typhi; transmission via fecal oral route following ingestion of contaminated food or water; invade M cells Presentation: fever, bradycardia, water diarrhea or constipation, abdominal pain, **salmon**-**colored** **rose** **spots** on chest/abdomen; **hepatosplenomegaly**; ulceration of Peyer's patches can result in GI bleeding; transmural necrosis can cause intestinal perforation Risk for becoming chronic carrier

Answer 30

It codes for **p-glycoprotein**, a **transmembrane** **ATP dependent efflux pump** protein that has a broad specificity for hydrophobic compounds. It can reduce the influx of drugs into the cytosol and increase efflux from the cytosol, thereby preventing the action of chemotherapeutic drugs.

Answer 31

Pathogenesis: HSV1; **dsDNA** **virus**, **enveloped** Presentation: primary infection - gingivostomatitis (vesicles on the lips and hard palate), fever, lymphadenopathy; recurrent infection - lip lesions that are less severe due to existing cellular and humoral immunity from prior infection Histology: intranuclear inclusion bodies, multinucleated giant cells on Tzanck smear

Answer 32

**Enveloped**: Hepadna (Hep B), Herpes, Pox **Non**-**enveloped**: Adenovirus, Papova (HPV), Polyoma (JC and BK)

Answer 33

Pathogenesis: n**eural crest orgin**, involves adrenal medulla, sympathetic chain Presentation: median age \<2y, abdominal mass, periorbital (orbital metastases), spinal cord compression from epidural invasion ("dumbell tumor"), opsoclonus-myoclonus syndrome: **nonrrhythmic** conjugate eye movements and involuntary jerking movements of the trunk and limbs **"dancing eyes and dancing feet"** Histology: small, round blue cells, Homer Wright rosettes Dx: elevated catecholamine metabolites (HVA, VMA); **n-myc** amplification predicts poor prognosis

Answer 34

Presentation: skin (telangiectasias, capt medusae), breast (gyecomastia), abdomen (ascites, firm or nodular liver, splenomegaly), GU (testicular atrophy), palmar erythemia, dupuytren contracture, clubbing Labs: **_Function_**: impaired biosynthetic capacity (**elevated PT\*\***, **hypoalbuminemia**), impaired transport and metabolic capacity (**elevated** **bilirubin**) these all are the _**greatest** **prognostic** **significance**_ Hepatocellular damage: markers of **hepatocyte injury** (elevated AST, ALT, AST\>ALT); Markers of **cholestasis/biliary injury** (elevated ALP, gamma-glutamyl transpeptidase) **Thrombocytopenia** (due to splenic sequestration of platelets)

Answer 35

Pathogenesis: **autosomal** **dominant**; inheritance of one mutated allele of **TP53** with somatic mutation of the second allele (**2-hit** **hypothesis**); p53 maintains integrity of genome by causing cells w/ mutant DNA to arrest in **G1/S stage** until damage is repaired; w/o p53 defective cells divide unchecked and become cancerous Presentation: young patient; history of **breast** cancer, **adrenal** cancer, **sarcoma** (connective tissue), **leukemia** (WBCs); **brain** tumors are also common;

Answer 36

It is used in case-control studies in order to **control** **confounding**. Matching variables should always be the potential confounders of the study (e.g., age, race). Cases and controls are then selected based on the matching variables to that both groups have a similar distribution in accordance w/ the variables.

Answer 37

Pathogenesis: Maternal hyperglycemia causes transplacental glucose transfer to fetus, which stimulates fetal insulin production which increases fat deposition and enhanced fetal growth; glucose freely crosses the placenta; however maternal insulin cannot Presentation: **macrosomia**; **hyperinsulinism** remains after birth due to **beta** **cell** **hyperplasia** and baby is transiently **hypoglycemic** and needs frequent feeding or parenteral glucose to prevent hypoglycemia Complications: premature delivery, congenital malformation, respiratory distress, polycythemia and hyperviscosity Tx: supportive care, beta cell hyperplasia resolves over time

Answer 38

Pathogenesis: Gallbladder functions to **actively absorb water** from bile; conditions that cause gallbladder hypomotility result in **excessive** dehydration of bile; promotes precipitation and accumulation of particulate material (e.g., cholesterol monohydrate crystals, calcium bilirubinate, mucus) in bile, forming viscous **biliary** **sludge** that can cause transiet bile duct obstruction (biliary colic); precursor to gallstone formation Presentation: biliary colic (RUQ pain assoc. w/ nausea); slow/incomplete gallbladder emptying in response to CCK stimulaton (this is consistent w/ **gallbladder** **hypomotility**) Risk factors: pregnancy, rapid wt loss, high spinal cord injuries, prolonged use of total parenteral nutrition or octreotide

Answer 39

Pathogenesis: increased pressure and volume of endolymph due to defective resorption of endolymph (**endolymphatic** **hydrops**); resultant distension of endolymphatic system causes damage to vestibular and cochlear components of inner ear Presentation: unilateral **tinnitus** w/ feeling of **fullness**, recurrent **vertigo** w/ lightheadedness, N/V, unilateral **sensorineural** **hearing** **loss**

Answer 40

Pathogenesis: otoliths in semicircular canals Presentation: brief episodes of **vertigo** brought on by head movement; no auditory symptoms

Answer 41

Pathogenesis: **inflammation** of vestibular nerve (viral or postviral) Presentation: **single episode of vertigo** that can last for days; severe vertigo but no hearing loss

Answer 42

MOA: increases vagal tone (slows conduction through AV node - rate control effect); NaK ATPase inhibition: increased intracellular Na and Ca (increases cardiac contractility) Presentation: Cardiac: **bradycardia** and j**unctional escape beats** due to increased AV nodal block; **hypokalemia** can **precipitate** toxicity by increasing digoxin **binding** to NaK-ATPase; however, **_elevated K_** is a sign of digoxin toxicity as inhibition of NaK-ATPase pumps **increases** extracellular K GI: anorexia, n/v, abdominal pain Neurologic: fatigue, confusion, weakness, **color** **vision** **alterations**

Answer 43

Patients experiencing a major depressive episode should be carefully screened for past **manic** episodes to rule out **bipolar** **disorder**. Antidepressant monotherapy should be avoided in patients w/ bipolar disorder due to risk of **precipitating** **mania**.

Answer 44

Pathogenesis: **autosomal** **dominant** CTG trinucleotide repeat expansion in **DMPK** gene leads to abnormal expression of **myotonin** **protein** **kinase**; anticipation phenomenon Presentation: early childhood to late adulthood, **Cataracts**, **Toupee** (early balding in men), **Gonadal** **atrophy**, **myotonia** (inability to relax voluntary muscle after rigorus effort), muscle wasting, arrythmia; **classic**: **difficulty** **loosening** one's grip after a handshake or inability to release doorknob Microscopy: **type 1 fibers** are more affected

Answer 45

Pathogenesis: Factor 7 deficiency Presentation: **hemarthroses** and excessive bleeding following tooth extraction; coagulopathies present w/ **deep-tissue bleeding** into joints, muscles, and subcutaneous tissues Labs: normal bleeding time (adequate platelet function), normal aPiTT (intact intrinsic coag system), **prolonged PeT** [Platelet defects present w/ **mucocutaneous** bleeding (e.g., epistaxis, petechiae).]

Answer 46

Pathogenesis: **X-linked recessive** disorder caused bya defect in **hypoxanthine-guanine phosphoribosyltransferase (HGPRT)**; this results in failure of the **purine salvage pathway**, leading to increased degradation of hypoxanthine and guanine to uric acid De novo **purine** synthesis must **increase** to replace lost bases, necessitating an increase in **phosphoribosly pyrophosphate (PRPP) amidotransferase** activity to supply sufficient quantity of purine nucleotides. Presentation: dystonia, choreoathetosois, self mutilation, and hyperuricemia in first few years of life

Answer 47

**IgE-dependent** mast cell degranulation: assoc. w/ environmental exposure such as foods or vespid stings or meds such as beta-lactam and sulfonamid antibiotics; opiods can cause IgE-dependent degranulation (very rare), but IgE independent reactions are more common **IgE-independent** mast cell degranulation: caused by **opioids**, **radiocontrast** agents, and some **antibiotics** (e.g., vancomycin); due to activation of PKA and PI3 kinase Presentation: **acute** **pruritis** following administration of drug; pain, bronchospasm, localized swelling

Answer 48

Pathogenesis: obstructive lesion caused by **incomplete** **degeneration** of the central portion of the **fibrous** **tissue** band connecting walls of vagina Presentation: **primary** **amenorrhea**, normal secondary sex characteristic w/ cycle abdominal or pelvic pain due to accumulationi of menstrual blood in vagina and uterus (e.g., **hematocolpos**); pressure from blood collection can cause back pain and difficulties w/ defecation; secondary sexual development is normal as there are no chromosomal or hormonal abnormalities

Answer 49

Usually involves the skin and GI tract (bloody diarrhea); common in HIV pts not on antiretroviral therapy Colonoscopy findings: reddish/violet flat maculopapular lesions to raised hemorrhagic nodules or polypoid masses Biopsy: **spindle** cells, **neovscularization**, and extravasated RBCs w/ **hemosiderin** **deposition**

Answer 50

Colonoscopy findings: non-ulcerative inflammation Biopsy: **Basophilic** **clusters** seen on surface of intestinal mucosal cells

Answer 51

The most common inherited cause of intellectual disability. Pathogenesis: **mutation** of fragile X mental retardation 1 (FMR1) gene on long arm of X chromosome; normally 5-55 CGG repeats; full mutation characterized by **\>200 CGG** trinucleotide repeats, which causes **FMR1** **hypermethylation**; DNA methylaton **inactivates** FMR1 preventing transcription and production of FMR1 protein thereby impairing neural development Presentation: maroorchidism, dysmorphic facies (long and narrow face, prominent forehead and chin); developmental delay, ADHD, autism; delayed language acquisition and poor social skills are suggestive of autism Dx: southern blot analysis used to measure degree of **methylation** and determine the **number of CGG repeats**

Answer 52

Dopamine is produced in the **ventral** **tegmental** **area** and **substantia** **nigra** **pars** **compacta**, located in the **midbrain**. NE in the brain is synthesized in the **locus** **ceruleus**, located in the posterior **rostral** **pons** near the **lateral floor of the 4th ventricle**. It projects to all parts of the CNS and helps control mood, arousal (reticular activating system), sleep wake states, cognition, and automonic function. Dynorphin is an opioid peptide that modulates pain response, produced in the **periaqueductal** gray, rostral **ventral** **medulla**, and dorsal horn of the spinal cord.

Answer 53

Pathogenesis: malnourishment; vit. C is cofactor for **hydroxylation** of proline and lysine in the **RER** Presentation: alcoholics, the poor, the elderly; gingival swelling/bleeding, petechiae, ecchymoses, poor wound healing (due to impaired collagen synthesis); perifollicular hemorrhages and coiled (**corkscrew**) hairs

Answer 54

A peripheral mononeuropathy caused by **compression** of the **median** nerve in the carpal tunnel. Pathogenesis: Assoc. w/ conditions that reduce carpal tunnel space - pregnancy (fluid accumulation), **hypothyroidism** (glycosaminoglycan buildup), DM (connective tissue thickening), RA (tendon inflammation), pts w/ long hx of hemodialysis through deposition of beta2 microglobulin (dialysis assoc. **amyloidosis**) Presentation: sensory impairment, pain, and/or paresthesias in the median nerve distribution (palma surface of the first 3 digits and radial half of 4th digit); sx are worse at night; motor weakness during thumb abduction/opposition and thenar **atrophy**, **Tinel** sign (**tapping** over flexor surface of the wrist reproduces sx) and **Phalen** sign (**flexion** of the wrist reproduces symptoms)

Answer 55

A partial opioid receptor agonist that binds w/ high affinity but has low intrinsic activity. In patients on **long**-**term** opoid therapy, buprenorphine acts as an opioid receptor **antagonist** in the presence of full opioid agonists, displaces them, **precipitates** **withdrawal** in opioid tolerant patients w/ chronic pain.

Answer 56

Pathogenesis: NSAIDs concentrate in renal medulla along medullary osmotic gradient, w/ higher levels in the **papillae**; **uncouple** **oxidative** **phosphorylation** and cause **glutathione** **depletion** w/ subsequent lipid **peroxidation** resulting in damage to tubular and vascular endothelial cells; prolonged use results in **chronic interstitial nephritis**; decrease prostaglandin synthesis causing constriction of medullary vasa recta and **ischemic papillary necrosis** Presentation: evidence of tubular dysfunction (polyuria, nocturia); calcification Labs: elevation in serum creatinine, mild proteinuria; hematuria, **sterile** **pyuria**

Answer 57

Pathogenesis: autoimmune destructioni of platelets by anti-platelet antibodies, likely IgG autoantibodies against the platelet membrane glycoproteins **GP2b/3a** Presentation: children - acute and self-limited; adults - insidious and chronic course in adults; epistaxis, eccymoses, mucosal bleeding, and marked **thrombocytopenia** w/ **no obvious** causes (meds, BM failure); **unremarkable** physical examination and lab findings Labs: normal hematocrit, leukocyte count and differential, fibrinogen level, and PT/INR

Answer 58

Cachexia is a syndrome that encompasses **anorexia**, **malaise**, **anemia**, **weight** **loss**, and **generalized** **wasting** due to underlying systemic disease. Pathogenesis: **TNF-alpha** is produced by **macrophages** in response to infection as well as by some neoplastic cells; TNF-alpha (**cachectin**) is a main mediator of pareneoplastic cachexia (along w/ IL1Beta and IL6); it influences the **hypothalamus** leading to **appetite** **suppression**; it also **increases** **basal** **metabolic** **rate** In bacterial infections, it produces **fever** (along w/ IL1), mediates sx of septic shock, and causes hepatic release of **acute** **phase** **reactions** (c-reactive protein and fibrinogen)

Answer 59

It is also known as expectancy bias. It occurs when investigators misclassify data due to preconceived expectation or prior knowledge concerning the study or its participants. This type of bias is particularly important when outcomes are subjective (i.e., involve person interpretation of clinical, microscopic, or radiographic findings). This type of bias can be reduced by conducting a blinded study in which observers are unaware of study details and patient characteristics that could undly influence them.

Answer 60

Pathogenesis: autosomal recessive disorder characterized by defective breakdown of branched chain amino acids (isoleucin, leucine, and valine); metabolized by branched chain alpha ketoacid dehydrogenase complex (BCKDC) which is mutated; BCKD requires **Thiamine**, **Lipoate**, **Coenzyme** A, **FAD**, **NAD** (Tender Loving Care For Nancy) Presentation: accumulation of branched chain amino acids in serum and peripheral tissues resulting in neurotoxicity that includes seizures, irritability, lethargy, and poor feeding; metabolite of isoleucine gives urine a **sweet** **odor** Tx: high dose **thiamine** (B1) treatment, but most still require lifelong dietary restrictions of isoleucine, leucine, and valine

Answer 61

Presentation: weight loss despite normal to increased food intake, **polyuria**, **polydipsia**, and fatigue; may present with diabetic ketoacidosis (n/v, abdominal pain, decreased mental status, fruity odor to breath) Dx: fasting glucose greater than or equal to 126mg/dL, random glucose greater than or equal to 200mg/dL, or an elevated hemoglobin A1c (greater than or equal to 6.5%) Oral glucose preferred screening method for gestational diabetes and cystic fibrosis-related diabetes; not preferred for general use b/c it is more expensive and less convenient

Answer 62

B/c exercising muscle **extract** additional O2, the venous blood O2 conent is **decreased**. The mixed venous blood CO2 content is increased due to increased CO2 **production**. The venous blood pH is decreased (more acidic). Hemostatic mechanism maintain arterial blood gas levels and arterial pH near the resting values.

Answer 63

A common condition characterized by the **loss** of epidermal melanocytes. Pathogenesis: **autoimmune** activity, melanocytic self-destruction

Answer 64

Janeway lesion: painless/**nontender**, macular erythematous lesions typically located on the palms and soles; they are the result of **septic** **embolization** and **valvular** **vegetations**; composed of bacteria, neutrophils (microabscesses), necrotic material, and subcutaneous hemorrhage; found in pts w/ acute infective endocarditis Osler nodes: painful/**tender**, violaceous nodules typically located in the pulp of fingers and toes; due to **immune**-**complex** **deposition** in the skin

Answer 65

Presentation: progressive dyspnea, fine crackles, clubbing, diffuse reticular opacities Histology: progressive pulmonary fibrosis w/ thickening and stiffening of the pulmonary **interstitium**, this causes **increased** **lung** **elastic** **recoil**, as well as airway widening due to **increased** outward pulling (**radial** **traction**) by surrounding fibrotic tissue, this leads to increased expiratory flow rates when corrected for the low lung volume; fibrosis causes a reduction in the diffusion capacity of CO PFTs: decreased in almost everything; FVC and FEV1 are decreased as well; however FEV1/FVC ratio is typically normal or increased as FEV1 decreases less than FVC (due to airway widening relative to low lung volumes); **decreased** **lung** **compliance**

Answer 66

Pathogenesis: traumatic event dislodges **fat** **globules** from BM and they travel to **pulmonary** **microvessels** (hypoxemia); fat emboli assoc. microvascular occlusion in the CNS and dermal capillaries; **platelets** adhere to and coat fat microglobules Presentation: acute onset **neurologic** abnormalities, **hypoxemia**, and a **petechial** **rash** in a pt w/ severe long bone and/or pelvic fractures; occurs w/in first 24-72 hours after injury, but can develop 2w later [**Red** **thrombus** lodged in pulmonary artery is consistent w/ thromboembolism from a deep venous source.]

Answer 67

Pathogenesis: may be a primary disorder or occur secondary to other autoimmune disease such as SLE Presentation: venous or arterial **thromboembolic** **disease** (DVT, pulmonary embolism, ischemic stroke/transient ischemic attack); **adverse** **pregnancy** **outcomes** (unexplained **pregnancy** **loss**, premature brith due to placental insufficiency or preeclampsia) Labs: **lupus anticoagulant** effect (**aPTT prolongation** in vitro, not reversed on plasma mixing studies; in vivo they produce a **hypercoaguable** **state**); presence of **anticardiolipin** antibody and **anti-beta1 glycoprotein** I antibody Antibodies cause false positive results on nontreponemal serologic syphilis tests (RPR and VDRL) by reacting w. cardiolipin (antigen used in those tests)

Answer 68

SAH occurs due to rupture of saccular (berry) aneurysm or arteriovenous malformation. **Severe** **vasospasm** 4-12d after the initial insult is the major cause of morbidity and mortality in patients recovering from SAH; can cause **cerebral** **ischemia** which presents as new-onset confusion and/or focal neurological deficit Tx: **Nimodipine**, a selective calcium channel blocker, is often prescribed to prevent vasospasm.

Answer 69

**Decreased LV chamber size** in the long axis from base to apex, which causes ventricular septum to acquire **sigmoid** **shape**; **Atrophy** of myocardium results in increased interstitial connective tissue/collagen deposition, with concomitant extracellular **amyloid** **deposition**; Progressive accumulation of cytoplasmic granules containing brownish **lipofuscin** pigment (the result of indigestible byproducts of subcellular membrane lipid oxidation)

Answer 70

Pathogenesis: **congenital**; **sporadic**, developmental anomaly of neural crest derivates due to somatic mosaicism for an **activating** **mutation** in one copy of GNAQ gene Presentation: unilateral port wine stain of face, tram track calcifications (opposing gyri), seizures/epilepsy, intellectual disability, episcleral hemaniogoma, increased intraocular pressure, early onset glaucoma Sprodic, port wine Stain, Tram track calcifications, Unilateral, Retardation, Glaucoma, GNAQ gene, Epilepsy

Answer 71

Pathogenesis: TSC1 mutation on ch9 or TSC2 mutation on ch16; tumor suppressor genes; autosomal dominant Presentation: harmartomas in CNS and skin, facial angiofibromas, mitral regurgitation, ash-leaf spots, cardiac rhabdomyoma, intellectual disability, renal angiomyolipoma, seizures, shagreen patches; Increased incidence of subependymal giant cell astrocytomas and ungual fibromas (nails)

Answer 72

Pathogenesis: deletion of VHL gene on ch3p; autosomal dominant; VHL ubiquinates hypoxia-inducible factor 1a; Presentation: characterized by development of numerous tumors, both benign and malignant; **Hemangioblastoms** (retina, brainstem, cerebellum, spine); can produce EPO **Angiomatosis** (cavernous hemangiomas in skin, mucosa, organs) bilateral **Renal** cell carcinomas **Pheochromocytomas**

Answer 73

Pathogenesis: autosomal recessive trinucleotide repeat disorder (**GAA**) on ch9; encodes frataxin (iron binding protein); impairs mitochondria; degeneration of CST (spastic paralysis), spinocerebellar tract (ataxia), DCT (vibration, proprioception) and dorsal root ganglia (loss of DTRs); Presentation: childhood w/ kyphoscoliosis; ataxia, frequent falling, nystagmus, dysarthria, DM, pes cavus, hammer toes, **HOCM** (cause of death)

Answer 74

Damage to anterior spinal artery or vertebral arteries. Presentation: Lateral **CST**: contralateral paralysis - upper and lower limbs **Medial** **lemniscus**: decreased contralateral proprioception Caudal medulla: ipslateral **hypoglossal** dysfunction (tongue deviates ipsilaterally)

Answer 75

Damage to anterior inferior cerebellar syndrome Presentation: Lateral pons 5/STT: decreased pain and temperature sensation from contralateral body, ipsilateral face 7: paralysis of face; decreased lacrimation, salivation, taste from anterior 2/3 of tongue 8: vomiting, vertigo, nystagmus; Labyrinthine artery: ipsilateral sensorineural deafness, vertigo Sympathetic: ipsilateral Horner syndrome Middle and inferior cerebellar peduncles: ataxia, dysmetria

Answer 76

Damage to the basilar artery. Presentation: Pons, medulla, lower midbrain: RAS spared = preserved consciousness CST and corticobulbar tracts: quadriplegia; loss of voluntary facial, mouth, and tongue movements Ocular CN nuclei, paramedian pontine reticular formation: loss of horizontal, but not vertical eye movements (can only look up and down)

Answer 77

A thickening of the **distal** **phalanges (DIP)** associated w/ a number of chronic diseases causing **hypoxia**. Pathogenesis: can be primary (idiopathic) or secondary to - Heart disease: **cyanotic** congenital heart disease (**Tetralogy of Fallot**, Truncus arteriosus, Transposition of the great arteries, Total anomalous pulmonary venous connection, Tricuspid atresia) and bacterial endocarditis Lung diseases: lung cancer (esp. large-cell carcinoma), tuberculosois, cystic fibrosis, bronchiectasis, pulmonary HTN, empyema, and other chronic lung disease assoc. w/ hypoxia Presentation: "**drumstick**" appearance of the fingers, flattening of the nail folds, and shininess of the nail and distal portion of the finger; pressing on nails produces spongy fluctuant sensation caused by softening of nail beds Other: Inflammatory bowel diseases (Chron's disease, ulcerative colitis), hyperthyroidism, and malabsorption

Answer 78

Pathogenesis: arises from DVT in lower extremities and lodges w/in arterial blood supply of lungs Presentation: suddent onset **dyspnea** in the setting of recent calf-swelling Risk factors: obesity, smoking, prolonged immobilizaiton Findings: increased dead space ventilation, increaed ventilation/perfusion mismatch in remainder of lungs w/ consequent **hypoxemia**; hyperventilate to increase O2 content hyperventilation leads to **hypocapnia** and **respiratory** **alkalosis**; serum bicarb remains normal in acute phase, but metabolic compensation w/ renal bicarb loss occurs afater approx. 48hs

Answer 79

They secrete alkaline mucus into the duodenum; pass through the muscularis mucosa and terminate in the mucosal crypts (crypts of Lieberkuhn); found in the **first part of the duodenum** [Epithelial cells of pancreatic ductules and ducts produce water secretion containing high concentrations of bicarb ions; emptied into duodenum at the ampulla] [Presence of acid in duo and jej cause release of secretin from mucosa, stimulating bicarb from submucosal glands and pancreas]

Answer 80

Pathogenesis: distortion or fracture of the stereocilia (of the **Organ** of **Corti**) due to shearing forces against the tectorial membrane Presentation: high frequency hearing lost first, regardless of the frequency of sound causing the damage Noise-induced hearing loss from trauma to **sterociliated** hair cells of the **organ of Corti**.

Answer 81

Vascular malformation (sporadic or familial) that occur w/in the **brain** **parenchyma (intracerebral)** above the cerebellar tentorium Histology: clusters of dilated, thin-walled capillaries w/ little or no intervening nervous tissue Presentation: seizures, progressive neurologic deficits due to mass effect w/ interruption of cerebral microcirculation; **increased tendency to bleed and for sezures** to occur

Answer 82

Pathogenesis: philadelphia chromosome (transloction between ch9 and 22) or the BCR-ABL fusion gene or mRNA Labs: elevated WBC w/ an increase in precursor forms (e.g., bands, metamyeloctyes, **myelocytes**); **decreased leukocyte (neutrophil) alkaline phosphatase** because WBCs are cytochemically **abnormal**; immature blasts are typically **less than 2%** [In leukemoid reaction: leukocytosis, normal or elevated leukocyte (neutrophil) alkaline phosphatase] tx: tyrosine kinase inhibitor

Answer 83

Pathology: ssDNA virus; respiratory, congenital or hematogenous transmission; initial nonspecific period assoc. w/ heavy viremia and viral shedding Presention: HA, coryza, GI sx, hemolytic anemia: transient aplatic crisis; Erythema infectiosum (5th disease): primarily in children; bright red rash on cheeks; generalized reticular rash on arms, legs, and trunk; signifies active immune response w/ formation of immune complexes and minimal or undetectable viremia (reduced infectivity) **Acute** **arthropathy**: primarily in adults, **symmetric** polyarthritis involving PIP, metacarpal, knee, and ankle joints mimics RA; **self-limiting** and nondestructive; signifies active immune response w/ formation of immune complexes and minimal or undetectable viremia (reduced infectivity)

Answer 84

Pathogenesis: benign tumor (glomangioma) of the **modified** **smooth** **muscles** cells of a glomus body; subungual melanoma (role = pigmentation) Glomus bodes: small, encapsulated neurovascular organs in dermis of nail bed, pads of fingers, toes, and the ears; Role: **thermoregulation** - shunt blood away from skin in cold temps to prevent heat loss; direct blood flow to skin in hot temps to facilitate heat dissipation Presentation: tender, small (mm), **red-blue** lesion under the nail bed

Answer 85

Pathogenesis: transmission of virus via **Aedes aegypti** mosquito; SEA, Pacific Islands, Caribbean, Americas) Presentation: acute febrile illnes, HA, **retro-orbital pain**, joint and muscle pain; **hemorrhage** (petechiae, purpura, epistaxis, melena) thrombocytopenia, leukopenia, and hemoconcentration Aedes also transmits virus causing **chikungunya** Presentation: febrile illness w/ flu-like sx, prominent polyarthralgias/arthritis (hands, wrists, ankles) and diffuse macular rash Prevention: protective barriers and inset spraying

Answer 86

**Short** (T1/2 \<6h): TOM (Triazolam, Oxazepam, Midazolam); minimizes daytime side effects **Intermediate** (T1/2 6-24h): LAT (Lorazepam, Alprazolam, Temazepam); minimizes daytime side effects **Long** (T1/2 \>24h): DCF (Diazepam, Chlordiazepoxide, Flurazepam)

Answer 87

Pathogenesis: Rapid onset anemia w/in 1st year of life due to intrinsic defect in erythroid progenitor cells Presentation: **short** **stature**, **craniofacial** abnormalities, and upper extremity malformation (**triphalangeal** thumbs, 3 instead of 2) Labs: **Nonmegaloblastic** macrocystic anemia

Answer 88

Pathogenesis: defective dna repair Presenation: megaloblastic anemia; unexplained fatigue, poor stature, growth

Answer 89

Pathogenesis: autosomal dominant mutation in uroporphyrinogen decarboxylase; leading to accumulation of **uroporphyrin** (tea colored urine) Presentation: blistering cutaneous **photosensitivity** (presents as **vesicles** and **blisters**) and **hyperpigmentation**; exacerbated w/ alcohol consumption, assoc. w. hep **C**

Answer 90

Mu opioid analgesics such as morphine can cause **contraction** of **smooth muscles** in the **sphincter of Oddi**; this leads to increased **pressures**/**spasms** in the common bile duct and gallbladder Presentation: biliary colic; severe pain and **cramping** in the right upper abdomen Tx: discontinuation of mu opioid analgesics and pain control with NSAIDs (ketorolac, diclofenac)

Answer 91

Type 2 DM is due to insulin resistance and relative insulin deficiency. Insulin resistance in adipose cells hinders antilipolytic effects of insulin, leading to lipolysis and release of FFA. Chronically elevated FFA levels contribute to insulin resistance by **impairing** insulin-dependent glucose **uptake** and **increasing** hepatic **gluconeogenesis**. Presentation: **acanthosis** **nigricans**

Answer 92

Pathogenesis: clonal mast cell proliferation in the bone marrow, skin, and other organs; associated w/ mutation in the **KIT** receptor tyrosine kinase; cells are characterized by prominent expression of mast cell **tryptase** Presentation: **excessive histamine** release from degranulation of mast cells mediates syncope, flushing, hypotension, pruritus, and urticaria; histamine induces gastric acid secretions, which can lead to gastric **ulceration**; excess acid inactivates pancreatic and intestinal enzymes causing **diarrhea**; n/v/ and **abdominal** **cramps**

Answer 93

Pathogenesis: benign, autosomal recessive disorder; **fructokinase** **deficiency**; **hexokinase** takes over role of fructose metabolism, converting dietary fructose into fructose 6 phosphate Presentation: dietary fructose is excreted unchanged in urine

Answer 94

In **healthy** individuals, **PaCO2** is the major stimulator of respiration. O2 has small effect on respiratory drive when its partial pressure in arterial blood is greater than 70mmHg **Central chemoreceptors**: located in **medulla**, stimulated by **decreased pH** in surrounding CSF (BBB is impermeable to H+, but CO2 diffuses and forms H+); **_PaCO2_** is major stimulator of central chemoreceptors; increased respiratory response to **hypercapnia**; pts with COPD have decreased sensitivity to PaCO2 and **hypoxemia** becomes important contributor to respiratory drive **Peripheral chemoreceptors**: found in carotid and aortic bodies; primary sites for sensing arterial **_PaO2_**; stimulated by **hypoxemia**; also stimulated by increased PaCO2 levels and blood H+ concentration (but central chemoreceptors are more important for increased respiratory response to hypercapnia); can be **suppressed** w/ **O2 administration**

Answer 95

Pathogenesis: excessive bleeding is common in patients w/ significant renal dysfunction due to accumulation of **uremic** **toxins** in circulation; toxins **impair** platelet **aggregation** and adhesion, resultin in qualitative platelet disorder Presentation: pt w/ ESRD develops bleeding at catheter exit site; no treatment for anticoagulants prior to procedure Labs: **increased** **bleeding** **time**; **normal** **platelet count, PT, and aPTT** Tx: uremic bleeding can be improved w/ **dialysis** as it removes toxins and partially reverses bleeding abnormality

Answer 96

Common, transient hypersensitivity disorder Pathogenesis: IgE-mediated degranulation of mast cells; non-IgE-mediated degranuation (e.g., opiates, radiocontrast agents, physical urticaria); mast cell independent mechanisms (e.g., aspirin, hereditary angioneurotic edema) Presentation: intensely pruritic, raised, erythematous plaques (wheals) that arise suddently and resolve over several hours; increased permeability of microvasculature leads to **edema** of **superficial** **dermis**; involvement of deep dermis and subcutaneous tissue is **angioedema** Histology: mixed inflammatory infiltrate (mononuclear cells, neutrophils, eosinophils) surrounding superficial dermal venules; overlying **epidermis** appears **normal**

Answer 97

Pathogenesis: low partial pressure of O2 in environments greater than 2500m (8000ft); **hypobaric** **hypoxia** = barometric pressure drops w/ increasing altitude, leading to decreased pO2 in air and blood; tissue hypoxia stimulates peripheral **chemoreceptors** causing **hyperventilation** decreasing pCO2 and increasing blood pH (respiratory alkalosis); renal bicarb excretion compensates for alkalosis stabiizing pH toward normal range w/in 48h Presentation: headache, fatigue, nausea, dizziness, sleep disturbances; most cases subside w/in 2d, but progression to life-threatening cerebral and/or pulmonary edema is possible

Answer 98

Necrotic infection of pulmonary parenchyma Pathogenesis: aspiration of anaerobic bacteria from oropharynx; untreated pneumonia; **neutrophils** are key player in formation - release cytotoxic granules (lysosomes) that destroy extracellular bacteria, but also cause significant damage to pulmonary parenchyma resulting in **liquefying** **necrosis** of lung tissue and (potentiallly) lung abscess Presentation: several days of fever, cough productive of **copious** **sputum** (often foul-smelling) CXR: **cavitation** w/ **air-fluid** level

Answer 99

Pathogenesis: **pulsion** (pushes)- **increased intraluminal pressure** created during straind bowel movements (e.g., chronic constipation); increased pressure causes the **mucosa** and **submucosa** to herniate through areas of focal **weakness** in **muscularis** (**false** diverticula); **Traction** (true) **diverticula**: created by inflammation and subsequent **scarring** of gut wall, results in pulling and outpouching of all gut wall layers (**true** diverticula); may occur in midesophagus due to mediastinal lymphadenitis caused by TB or fungal infection Presentation: greater than 60yo; affects sigmoid colon, hematochezia; inflammed (diverticulitis; causes lower quadrant abdominal pain, low-grade fever, constipation or diarrhea)

Answer 100

**True**: outpouching that contains all layers (mucosa, submucosa, **muscularis**, and serosa) ex: Meckel's, normal appendix, traction diverticula **False/pseudo**: outpouching only contains muscosa and submucosa, serosa ex: Zenker's esophageal, diverticulosis

Answer 101

Peritoneum: **simple** squamous epithelium (mesothelium) Ovary: simple **cuboidal** (e.g., germinal) Fallopian tube: simple **columnar** (**ciliated**) Uterus: simple **columnar** Cervix: endocervix - simple **columnar**; ectocervix - **stratified** squamous non-keratinized Vagina: stratified squamous non-keratinized

Answer 102

Mesonephros: interim kidney for 1st trimester; later contributes to male genital system Metanephros: permanent - **uteric** **bud**: derived from caudal end of **mesonephric** **duct**; gives rise to ureter, pelvises, calyces, and collecting ducts - metanephric **mesenchym** (metanephric blastema): interacts with uteric bud; formation of **glomerulus** through to **distal** **convoluted** **tubule**

Answer 103

Pathogenesis: hereditary, ischemia, **multiple** **myeloma**, **nephrotoxins**, **lead** **poisoning** Defects: generalized reabsorption defect in **PCT** leads to increased excretion of glucose, amino acids, bicarb, and phosphate (any substance reabsorbed by PCT) Presentation: metabolic **acidosis** (proximal RTA), **hypophosphatemia**, **osteopenia**

Answer 104

Pathogenesis: autosomal recessive Defects: resorptive defect in **TAL** of Henle (affects Na, K, and Cl transporter) Presentation: metabolic **alkalosis**, **hypokalemia**, **hypercaliuria** (similar to using a loop diuretic)

Answer 105

Pathogenesis: autosomal recessive Defects: reabsorption defect of **NaCl** in **DCT** Presentation: metabolic alkalosis, hypomagnesemia, hypokalemia, hypocalciuria (presents similarly to lifelong thiazide diuretic use; less severe than Bartter syndrome)

Answer 106

Pathogenesis: Autosomal dominant Defect: gain of function mutation leads to increased activiaty of Na channel leading to increased Na **reabsorption** in collecting tubules Presentation: metabolic **alkalosis**, **hypokalemia**, **hypertension**, decreases in **aldosterone** Presents similarly to **hyperaldosteronism**, but aldosterone is nearly undetectable due to negative feedback from **Na**; Tx: **amiloride**

Answer 107

Pathogenesis: autosomal recessive; can acquire disorder from **glycyrrhetinic** **acid** (present in licorice), which **blocks** activity of 11beta hydroxysteroid dehydrogenase Defects: in cells containing mineralocorticoid receptors, **11beta hydroxysteroid dehydrogenase** **converts** **cortisol** (activates receptors) to **cortisone** (inactive on receptors); Hereditary deficiency of 11beta hydroxysteroid dehydrogenase leads to excess **cortisol** leading to increase in **mineralocorticoid** activity Presentation: metabolic alkalosis, **hypokalemia**, **HTN**, decrease serum aldosterone level (cortisol tries to be the **SAME** as **aldosterone**) Tx: treat w/ K sparing diuretics (decrease mineralocorticoid effects) or **corticosteroids** (**decrease** endogenous **cortisol** production)

Answer 108

Pathogenesis: amphotericin B toxicity, analgesic nephropathy, congenital anomalies, autoimmune diseases Defect: inability of **alpha** **intercalated** cells to **secrete H+**, no new HCO3- is generated = metabolic **acidosis** Labs: basic urine, low serum K, increased risk for Calcium Phosphate kidney stone due to **increased** urine pH and increased bone turnover

Answer 109

Pathogenesis: Fanconi syndrome, multiple myeloma, carbonic anhydrase inhibitors Defect: defect in **PCT** **HCO3**- **reabsorption** leads to increased excretion of HCO3 inurine = **metabolic** **acidosis** Increased risk for **hypophosphatemic** rickets (in Fanconi syndrome; don't absorb P)

Answer 110

Pathogenesis: **decrease** in **aldosterone** production (heparin) or aldosterone resistance (TMP-SMX) Defects: hypoaldosteronism or aldosterone resistance; **hyperkalemia** leads to **decreased** **NH3** synthesis in PCT leading to _**decreased** **NH4**+ excretion_

Answer 111

**WAGR complex:** Wilms tumor, Aniridia (absence of iris), Genitourinary malformations, mental Retardation/intellectual disability (WT1 **deletion**) Denys-Drash syndrome: Wilms Tumor, Diffuse mesangial **sclerosis** (early onset **nephrotic** syndrome), **Dysgenesis** of gonads (male pseudohermaphroditism) (WT1 **mutation**) Beckwith-Wiedemann Syndrome: Wilms tumor, **macroglossia**, organomegaly, **hemihyperplasia** (**WT2** **mutation**)

Answer 112

MAD HUNGER Metabolic **acidosis** Dyslipidemia (esp. increased **triglycerides**) Hyperkalemia **Uremia** (nausea, anorexia, pericarditis, asterixis, encephalopathy, platelet dysfunction) Na/H20 **retention** (HF, pulmonary edema, HTN) Growth retardation and developemntal delay **EPO** failure (anemia) Renal osteodystrophy (bone disease due to failure of maintaining **Ca** and **P** in blood)

Answer 113

Increased TSH and decreased T4. T3 is produced mainly in peripheral tissues and has a short half-life so serum T3 levels fluctuate widely and correlate poorly w/ clinical status. T3 is often **normal** in **primary** **hypothyroidism**.

Answer 114

MOA: a combination of sulfapyridine (antibacterial) and 5-aminosalicyclic acid (anti-inflammatory); activated by colonic bacteria Indication: **ulcerative** **colitis**; **crohn** **disease** (colitis component) SEs: malaise, nausea, sulfonamide toxicity, reversible **oligospermia**

Answer 115

Daily headaches at **temples**, bilaterally Confusion, memory issues; **forgetfulness** Broad-based **ataxic** gait; **slow** to answer questions

Answer 116

A protein that recruits an E2 ubiquitin-conjugating enzyme that has been loaded w/ ubiquitin, recognizes a protein substrate, and assists or directly **catalyzes transfer** of ubiquitin from E2 to the protein substrate

Answer 117

In the elderly: **confusion**, decreased alertness Low blood pressure (hypotensive) **refractive** to isotonic saline

Answer 118

Inflammatory facial skin disorder characterized by erythematous papules and pustules, but no comedones. May be assoc. w. facial **flushing** in response to **external** **stimuli** (alcohol, heat). Phymatous rosacea can cause rhinophyma (bullous deformation of **nose**). Tendency to **blush** or **flush** more; redness can **spread** **beyond** nose and cheeks to forehead and chin; **telangiectasias**

Answer 119

A lesion in the **optic tract** causes contralateral homonymous hemianopia and a relative **afferent** **pupillary** **defect** (Marcus Gunn pupil) in the pupil **contralateral** to the tract lesion. **Nasal** portion of the retina contributes more input to pretectal nucleus than the temporal portion of the retina.

Answer 120

Pts commonly die of hypertension-associated complication, including LV failure, ruptured dissecting aortic aneurysm, and **intracranial hemorrhage**. At increased risk for ruptured **intracranial aneurysms** b/c of increased incidence of **congenital berry aneursyms** of the circle of willis as well as aortic arch hypertension.

Answer 121

Lifetime hx of at **least 2 weeks** of psychotic symptoms (delusions, hallucinations) **without** significant mood disturbance (major depressive or manic episode) is a key requirement for schizoaffective diagnosis. However, mood symptoms **must be present** for most of the illness.

Week 6 Flashcards

(145 cards)