Currently circulating genotypes of hepatitis E virus in India, 2014-2018

Role of real-time polymerase chain reaction in diagnosing Hepatitis E, the commonest cause of acute hepatitis in adult patients seeking institutional care

Background

This cross-sectional study was performed with the aim of determining the prevalence of hepatitis E virus (HEV) infection among acute hepatitis patients attending a tertiary care teaching hospital in a developing country and to determine the relative performance of prevalent diagnostic assays in establishing its diagnosis.

Materials and Methods

A total of 46 adult patients were included in this study, all of whom presented with jaundice of <4 weeks' duration and elevation of AST and ALT above 500 U/L. The prevalence of HEV among patients with acute hepatitis was calculated on the basis of the proportion of recruited patients reacting positively in serum anti-HEV immunoglobulin M (IgM) and real-time polymerase chain reaction (RT-PCR) assays.

Results

Among the recruited patients, 11 (23.91%) and 15 (32.6%) patients were positive for anti-HEV IgM and RT-PCR, respectively. The two tests demonstrated poor inter-test agreement, thereby implying the necessity of performing both tests for reliable diagnosis of acute HEV virus infection. We also observed a significant difference in the duration of illness between RT-PCR positive and negative patients (P = 0.008). The mean (±SD) duration of illness in the two groups was 8.6 (±3.50) and 11.66 (± 5.15) days, respectively. Combining the results of IgM ELISA and RT-PCR, we observed that 23 out of 46 patients (50%) had evidence of acute HEV virus infection among our patients.

Conclusion

Our study suggests that HEV is the commonest cause of acute hepatitis in adult patients attending a tertiary care teaching hospital and that the diagnostic algorithm for its confirmation should include both IgM ELISA and RT-PCR assays.

Severe maternal-fetal pathological damage and inflammatory responses contribute to miscarriage caused by hepatitis E viral infection during pregnancy

BACKGROUND

Hepatitis E virus (HEV) infection causes serious adverse pregnancy outcomes during pregnancy. However, the maternal and fetal damage induced by HEV infection is rarely reported.

METHODS

A BALB/c pregnant mouse model was established to explore the maternal and fetal pathological damage and inflammatory responses caused by HEV infection.

RESULTS

Notably, miscarriages and stillbirths were observed in HEV-infected pregnant mice. HEV infections were identified by qRT-PCR, immunohistochemical analysis and immunofluorescence assay in the uterus, placenta, umbilical cords and livers and brains of fetuses. Serious inflammatory responses and pathological damage were triggered in the uterus and placenta of HEV-infected pregnant mice. Vertical transmission of HEV resulted in severe pathological damage and inflammatory responses in the livers and brains of fetuses, as well as emerging apoptosis cells in the brains of fetuses. Most of the cytokines/chemokines in the sera were significantly increased in the HEV-infected pregnant mice. Remarkably, cytokines/chemokines were significantly different between HEV-infected pregnant and miscarriage mice; IL9, GM-CSF and IL1α were the most important three cytokines/chemokines in determining the pregnancy outcomes.

CONCLUSION

HEV infections cause serious maternal/fetal pathological damage, inflammatory responses and apoptosis, which may be responsible for adverse pregnancy outcomes.

Application of a truncated ORF2 protein-based ELISA for diagnosis of hepatitis E in an endemic area

Enterically transmitted waterborne hepatitis E (HE) caused due to hepatitis E virus (HEV) prevails as a significant public health problem endemic to India. Due to short-term viremia/fecal excretion and poor in vitro transmissibility of HEV, HE diagnosis depends on detection of specific IgM antibodies in serum. Present study evaluated performances of two in-house and six commercial IgM detection enzyme-linked immunosorbent assays (ELISAs) using sera collected from volunteers/acute hepatitis patients (n = 716). The in-house ELISAs were based on complete and truncated open reading frame 2 (ORF2) proteins containing neutralizing epitope/s region of genotype 1 HEV (ORF2p, 1-660 amino acid (a.a.) and T1NEp, 458-607 a.a., respectively). The commercial ELISAs included Wantai (China), MP Diagnostics (MPD) (Singapore), DIA.PRO Diagnostics (Italy), MBS (Italy), abia (Germany), and ImmunoVision (USA). T1NE ELISA showed 97.0% positive percent agreement (PPA), 99.4% negative percent agreement (NPA), and 98.6% concordance (κ = 0.97, P = 0.0000) with ORF2 ELISA. ORF2, T1NE, Wantai, and MPD ELISAs agreed on results for 88% of sera tested. Two percent sera showed reactivity in each combination of three and two of aforementioned four ELISAs. Remaining 8% sera were single ELISA reactive. PPA and NPA value ranges were 76.3-99.0% and 84.8-99.5%, respectively. Pairwise concordances between all the eight ELISAs ranged from 88.0 to 100% (κ: 0.74-1.00). Both the in-house ELISAs agreed better with Wantai over MPD ELISA. In conclusion, both ORF2 and T1NE ELISAs were equally efficient in diagnosing HEV infections. T1NEp proved to be an excellent tool in HE sero-diagnosis and is worth exploring in development of simple rapid tests. KEY POINTS: • In-house ELISA based on bacterially expressed neutralizing epitope/s region protein • In-house ELISA based on complete ORF2 protein expressed in insect cells • Comparison of two in-house and six commercial anti-HEV IgM antibody detection ELISAs.

Transfusion-transmitted hepatitis E: What we know so far?

Hepatitis E virus (HEV) is a major cause of viral hepatitis globally. There is growing concern about transfusion-transmitted HEV (TT-HEV) as an emerging global health problem. HEV can potentially result in chronic infection in immunocompromised patients, leading to a higher risk of liver cirrhosis and even death. Between 0.0013% and 0.281% of asymptomatic blood donors around the world have HEV viremia, and 0.27% to 60.5% have anti-HEV immunoglobulin G. HEV is infectious even at very low blood concentrations of the virus. Immunosuppressed patients who develop persistent hepatitis E infection should have their immunosuppressant regimen reduced; ribavirin may be considered as treatment. Pegylated interferon can be considered in those who are refractory or intolerant to ribavirin. Sofosbuvir, a nucleotide analog, showed modest antiviral activity in some clinical studies but sustained viral response was not achieved. Therefore, rescue treatment remains an unmet need. The need for HEV screening of all blood donations remains controversial. Universal screening has been adopted in some countries after consideration of risk and resource availability. Various pathogen reduction methods have also been proposed to reduce the risk of TT-HEV. Future studies are needed to define the incidence of transmission through transfusion, their clinical features, outcomes and prognosis.