Serological assessment of HEV in unexplained acute hepatitis

Background: Hepatitis E virus (HEV) infection is considered a rare cause of acute hepatitis in industrialized countries. However, this view is challenged by several reports of autochtonous hepatitis E in Western countries such as France, the Netherlands and the UK. No systematic analysis of HEV infection has been performed yet in Belgium. We therefore decided to retrospectively assess serological markers of HEV infection in cases of liver injury not due to infection with more common hepatotropic viruses. Methods: Frozen serum samples, collected in Ghent University Hospital between 2008 and 2010, were considered eligible for this study if an elevation in serum transaminases was present, if the patient had clinical evidence of acute hepatitis, if anti-HAV IgM, HBV surface antigen, anti-CMV IgM and anti-EBV IgM levels had been determined for routine diagnostic purposes (reflective of possible infectious origin of the hepatitis), and if these markers had been found to be negative. Cases with a clear explanation for the hepatitis were ruled out. Selected sera (n=25) were analyzed for the presence of anti-HEV IgM and anti-HEV IgG using a commercial ELISA method that has been reported to be more sensitive than other assays (Biorex Diagnostics). Results: Mean serum transaminase levels were 445 IU/L for ALT (range, 76-3202 IU/L) and 287 IU/L for AST (range, 30-1169 IU/L). Three out of the 25 samples had an increased anti-HEV IgG level, whereas none of the samples was positive for anti-HEV IgM. Conclusion: HEV infection is not a common cause of acute hepatitis in our study