4/30 - UWorld

Question 1

What are the substances within the fluorescent areas in posttrep glomerulonephritis?

Answer 1

IgG, IgM, and C3

Question 2

What is the characteristic immunologic cells found in sarcoidosis?

Answer 2

Elevated CD4+/CD8+ T-cell ratio in bronchoalveolar lavage fluid

Question 3

What is the mutated gene involved in renal cell carcinoma?

Answer 3

VHL

Question 4

Describe the mechanism behind cyanide poisoning

Answer 4

♣ Hemoglobin with oxidized form of Hb (Fe3+) that does not bind O2 readily but has increased affinity for cyanide
• Can be caused by oxidation via nitrates or sulfonamides
♣ Presents with cyanosis and chocolate-colored blood
♣ You can induce methemoglobinemia with nitrites (will oxidize Fe2+ to Fe3+) in order to treat cyanide poisoning
♣ Treatment of methemoglobinemia:
• Methylene blue
• Vitamin C

Question 5

Describe the mechanism behind carbon monoxide poisoning

Answer 5

♣ Hb bound to CO instead of O2
♣ It decreases O2 bound to Hb but also causes a L shift in the curve
• Hb bound to O2 is decreased because it is bound to CO instead the height of curve is lower
o Decreased O2 content in the blood
• The heme groups NOT bound to CO have increased affinity for O2 L shift of curve
o This makes it more difficult for O2 to be unloaded in tissues
♣ These 2 effects together lead to very low O2 delivery to the tissues
♣ Treat with 100% O2

Question 6

What type of vaccination is offered for strep pneumonia?

Answer 6

Polysaccharide vaccine and conjugate vaccine (polysaccharide-protein conjugate)

Question 7

Features of Gardner syndrome

Answer 7

Familial adenomatous polyps

Osteomas/soft tissue tumors (osteoma of facial bone)

Impacted/supernumerary teeth

Question 8

Causes of hepatic encephalopathy

Answer 8

Liver disease (urea cycle occurs in hepatocytes)

Urea cycle enzyme deficiency (ornithine transcarbamylase is the most common deficiency)

Question 9

What structures are responsible for b-hCG production?

Answer 9

Syncytiotrophoblasts

b-hCG functions to maintain corpus luteum until placenta takes over for estrogen and progesterone synthesis

b-hCG reaches highest levels at 9 weeks, and then drops to very low levels once corpus luteum degenerates

Question 10

Enzyme deficiency in fructose intolerance?

Answer 10

Aldolase B

Question 11

What test is often used instead of bacitracin?

Answer 11

Pyrrolidonyl arylamidase (PYR) test

Strep Pyogenes is PYR-positive aka Bacitracin sensitive

Question 12

What is Mallory Weiss syndrome?

Answer 12

o Tear of the gastroesophageal junction caused by excessive/forceful vomiting

Question 13

Treatment for neuroleptic malignant syndrome

Answer 13

Dantrolene (muscle relaxant)

Bromocriptine (D2 receptor agonist)