Evaluation of the VIDAS hepatitis E IgM test in a nonendemic region

Hepatitis E virus (HEV) causes worldwide more than 20 million new hepatitis cases yearly. These infections can take on fulminant forms or cause severe extrahepatic manifestations, and integration into hepatitis differential diagnosis is recommended. In developed countries, genotypes 3 and 4 are most common, mainly through zoonotic transmission. HEV diagnosis is usually first approached with serological methods, sometimes completed with PCR. In this study, we tested the VIDAS anti-HEV immunoglobulin M assay for its specificity on 181 serum samples from patients infected with selected pathogens possibly causing comparable symptoms or false-positive hepatitis E IgM, such as cytomegalovirus, enterovirus, or other hepatitis viruses. Additionally, serum samples were included from 29 patients who tested positive for autoantibodies in immune-mediated liver disease. We report 8 false-positives (specificity 96%), predominantly for hepatitis A, Epstein-Barr virus, and cytomegalovirus, with numbers that are generally lower than reported for comparable assays. A small sensitivity study showed that its use is limited in immunocompromised patients, for whom molecular detection is recommended as first-line test.