A 20-year-old woman presents with a 2-week history of fever, malaise, and brown-colored urine. She recently visited Mexico. Physical examination reveals jaundice, mild hepatomegaly, and tenderness in the right upper quadrant. The serum bilirubin is 7.8 mg/dL, with 60% in the conjugated form. Serum levels of AST and ALT are markedly elevated (400 and 392 U/L, respectively). Serum albumin and immunoglobulin levels are normal. Serum IgM anti-hepatitis A virus (anti-HAV) is positive. IgG anti-hepatitis B surface antigen (anti-HBsAg) antibodies are positive. Anti-hepatitis C virus antibodies are negative.What is the most likely diagnosis?
High-Yield Explanation
HAV RNA Transmitted by the fecal-oral route and may be contracted by contamination of water and food. Never pursues a chronic course, does not have a carrier state, and provides life-long immunity. IgM anti-HAV is identified in acute infections. -The presence of serum IgG anti-HBsAg indicates prior exposure to hepatitis B virus but does not reflect active disease . -Individuals with chronic hepatitis B do not have detectable anti-HBsAg in their blood. -Acute and chronic hepatitis C are ruled out by the negative serology.