Good Performance of Immunoglobulin M Assays in Diagnosing Genotype 3 Hepatitis E Virus Infections

Abstract

We have evaluated three anti-hepatitis E virus (anti-HEV) immunoglobulin M (IgM) assays, the EIAgen HEV IgM assay (Adaltis), the HEV IgM enzyme-linked immunosorbent assay 3.0, and the Assure HEV IgM rapid test (MP Diagnostics), for the routine detection of acute genotype 3 HEV. Their sensitivities were fairly good (90%, 88%, and 82%), and their specificities were excellent (100%, 99.5%, and 100%).The hepatitis E virus (HEV) is an RNA virus whose genome comprises three open reading frames (ORFs). Four HEV genotypes are identified (12). In countries where HEV is endemic, most of the HEV samples belong to genotype 1 or 2 (9). Autochthonous infections also occur in industrialized countries with genotype 3 HEV (2, 10, 14). Most of the serological assays for diagnosing HEV use recombinant proteins derived from the ORF2 and/or ORF3 proteins. It has been reported that anti-ORF2 antibodies are not specific (13). The sensitivities of the serological assays for immunoglobulin M (IgM) have been found to vary greatly, from 42% to 93% (6,8,11,16). Current commercial serological assays are based on genotype 1 and 2 antigens and thus may be less sensitive for detecting infections with genotype 3 or 4 (4, 15). As there is increasing awareness of HEV in industrialized countries, we have assessed the performance of three serological assays for diagnosing genotype 3 HEV infections: two microplate enzyme immunoassay tests, the EIAgen HEV IgM kit (Adaltis) and the HEV IgM enzyme-linked immunosorbent assay (ELISA) 3.0 (MP Diagnostics), and an immunochromatographic assay, the Assure HEV IgM rapid test (MP Diagnostics).The sensitivities of the three IgM assays were assessed using 50 HEV RNA-positive samples from French patients with symptoms of acute hepatitis (49 samples with genotype 3 HEV

Genotype 3 Diversity and Quantification of Hepatitis E Virus RNA

“…Because serological tests may lack sensitivity (9,29), the detection of virus genomic RNA in serum or stool samples by RT-PCR is a crucial marker of an acute or a chronic HEV infection. The ubiquitous nature of HEV genotype 3 strains in domestic pigs and wild boars also raises public health concerns for zoonotic infection through direct contacts with infected animals (5,7,38) or the consumption of contaminated animal products (6,30,45).…”

Hepatitis E Virus: What Transplant Physicians Should Know

“…However, HEV RNA then becomes undetectable in the serum in ∼3 weeks after the onset of symptoms, although it remains detectable in the stools for two additional weeks (1). A diagnosis of HEV infection can be made either by detecting HEV RNA or by indirectly detecting anti-HEV IgM directed against a range of recombinant viral antigens using enzyme immunoassays or immunochromatographic kits (6). All four genotypes elicit similar antibody responses and seem to represent a single serotype (7).…”

Performance of Two Commercial Assays for Detecting Hepatitis E Virus RNA in Acute or Chronic Infections

“…Most infections in industrialized countries are due to zoonotic transmission, often of genotype 3 (HEV3); subtypes 3a and 3b are frequent in North America and Japan, and subtypes 3c, 3e, and 3f are more prevalent in Europe (3-5). HEV3 is an emerging concern for immunocompromised patients, as it can lead to chronic infection and cirrhosis (6-12).As evaluations of anti-HEV IgM assays revealed appreciable variations in their performances (13,14), it is important to diagnose HEV infections by detecting HEV RNA. Several in-house reverse transcription-PCRs (RT-PCRs) were recently evaluated, and their sensitivities were shown to differ greatly (15).…”

“…As evaluations of anti-HEV IgM assays revealed appreciable variations in their performances (13,14), it is important to diagnose HEV infections by detecting HEV RNA. Several in-house reverse transcription-PCRs (RT-PCRs) were recently evaluated, and their sensitivities were shown to differ greatly (15).…”