Friday, November 24, 2017

Repeated USMLE Questions Step 1- 205

A 20-year old female student represents with a 1-week history of nausea, vomiting and anorexia. She returned 2-weeks ago from a trip to Guatemala. On physical examination, her temperature was 100.3 F, clear chest and she has mild jaundice and a palpable tender liver. Her CBC was normal and her liver function tests are as follows: Serum total bilirubin 3.1 mg/dL. Serum aspartate aminotransferase 1100. Serum alanine aminotransferase 1900. Serum alkaline phosphatase 112. What is the most likely lab test to confirm your diagnosis?

A- IgM antibody to hepatitis A virus

B- Antibody to hepatitis B surface antigen

C- Antibody to hepatitis C virus

D- DNA for Epstein-Burr virus

E- Serum anti-mitochondrial antibodies


This patient has typical presentation of hepatitis A virus infection. His recent travel, short incubation period and mode of infection in addition to lab results confirm this diagnosis. The only option that is almost always positive in hepatitis A virus recent infection is IgM antibody to hepatitis A virus.

The correct answer is A

No comments:

Post a Comment