Atypical manifestations of hepatitis A infection: a prospective, multicenter study in Korea

The clinical outcome of symptomatic hepatitis A and the incidence and clinical characteristics of atypical presentation of hepatitis A were studied using prospective, multicenter design. The atypical presentation included delayed anti-hepatitis A virus (HAV) immunoglobulin M (IgM) seroconversion defined as positive anti-HAV IgM on the repeated test within 7 days of hospital admission after the initially negative result, prolonged cholestasis, and acute kidney injury (AKI). A total of 595 patients with symptomatic hepatitis A requiring hospital admission were enrolled prospectively from September 2006 to August 2008 in four major hospitals in a Korean city with a population of approximately 1 million. Clinical outcomes of symptomatic hepatitis A showed a case fatality rate of 0.2%, and fulminant hepatitis in 0.5%. Delayed anti-HAV IgM seroconversion was found in 6.4%, and was significantly associated with shorter intervals from symptom onset to hospital admission, higher body mass index, and lower alanine aminotransferase (ALT) level at admission. Prolonged cholestasis was found in 4.7% of patients, and could be predicted by preexisting chronic hepatitis B viral infection, prolonged prothrombin time, and higher total bilirubin level. AKI was complicated in 1.5%, which could be predicted by lower albumin level, higher ALT level, and higher white blood cell (WBC) count. More than half of the patients required hemodialysis. Substantial occurrence of delayed anti-HAV IgM seroconversion, prolonged cholestasis, and AKI was confirmed with various predictable factors, which could be helpful for accurate diagnosis and management of hepatitis A patients.