Abstract
BACKGROUND: Hepatitis E virus (HEV) is a significant cause of acute viral hepatitis, particularly in regions with poor sanitation. Co-infection with hepatitis B virus (HBV) is common in high-risk populations, such as individuals with chronic liver disease, but data on HEV prevalence in patients living with HBV in Southeast Asia are limited. This study investigates HEV seroprevalence among patients with HBV and those with hepatitis of unknown etiology (HUE) in central Vietnam. METHOD: Blood samples from 587 patients with HBV and 158 individuals with HUE were collected and analyzed for anti-HEV immunoglobulin G (IgG) and immunoglobulin M antibodies by enzyme-linked immunosorbent assay. HEV RNA was detected using reverse transcriptase-polymerase chain reaction, and HBV viral load was quantified via real-time polymerase chain reaction. RESULTS: The overall anti-HEV IgG seroprevalence was 26% in patients with HBV and 36% in those with HUE. Although patients with liver cirrhosis and hepatocellular carcinoma exhibited higher rates of anti-HEV IgG seropositivity, these differences were not statistically significant. Among patients with HBV, the seroprevalence was highest in those with liver cirrhosis and hepatocellular carcinoma (46%), whereas the lowest (24%) was found in patients with symptomatic chronic hepatitis B. Only 1 (0.1%) tested positive for anti-HEV immunoglobulin M, and no HEV RNA positivity was detected. Furthermore, biochemical laboratory parameters in patients with liver diseases were not found to be associated with anti-HEV seropositivity. CONCLUSIONS: Anti-HEV IgG seroprevalence was relatively high among patients with chronic liver disease, including those with HBV. However, no association was observed between HEV exposure and liver disease progression. HEV is not a common cause of hepatitis in Central Vietnam.