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