Acute hepatitis E virus infection in Taiwan 2002-2006 revisited: PCR shows frequent co-infection with multiple hepatitis viruses

Sporadic cases of acute hepatitis E virus (HEV) infection with production of anti-HEV IgM have been reported occasionally in Taiwan despite no reported outbreaks in the past. This study was undertaken to determine whether serological markers correlated with virus detection. From 2002 to 2006, 72 reported cases of acute hepatitis E seropositive for anti-HEV IgM in Taiwan were enrolled for investigation. Acute phase serum samples were collected for detection of HEV RNA, HBV DNA, HCV RNA, and GBV-C RNA by PCR. The results showed that viral sequences of HEV, HBV, HCV and GBV-C were detected in 54 (75%), 21 (29.2%), 9 (12.5%), and 22 (30.6%) of cases, respectively. Acute hepatitis A co-infection was excluded in all patients because none were seropositive for anti-HAV IgM and, nine patients (12.5%) did not seroconvert to anti-HEV IgG. These results suggest that serum markers did not correlate completely with viremia in the diagnosis of acute HEV infection. Multiple viruses may co-infect with acute hepatitis E virus in Taiwan. Detection of hepatitis E viremia together with seropositivity for anti-HEV IgM and followed by seroconversion to anti-HEV IgG should be included in the diagnostic criteria for HEV infection.