Clinical characteristics of hepatitis E in a "Non-Endemic" population

Acute liver failure caused by hepatitis E virus genotype 3 and 4: A systematic review and pooled analysis

BACKGROUND & AIMS

Acute liver failure caused by hepatitis E virus genotype 3 and 4 has been rarely described. Because of the presence of a short golden therapeutic window in patients with viral acute liver failure from other causes, it is possible that early recognition and treatment might reduce the morbidity and mortality. We performed a systematic review and pooled analysis of acute liver failure caused by hepatitis E virus genotype 3 and 4.

METHODS

Two reviewers appraised studies after searching multiple databases on June 12th, 2017. Appropriate tests were used to compare hepatitis E virus genotype 3 vs 4, suspected vs confirmed genotypes, hepatitis E virus-RNA positive vs negative, and to discern important mortality risk factors.

RESULTS

We identified 65 patients, with median age 58 years (range: 3-79), and a male to female ratio of 1.2:1. The median bilirubin, ALT, AST and alkaline phosphatase (expressed by multiplication of the upper limit of normal) levels were 14.8, 45.3, 34.8 and 1.63 respectively. Antihepatitis E virus IgG, antihepatitis E virus IgM and hepatitis E virus-RNA were positive in 84%, 91% and 86% of patients respectively. The median interval from symptoms onset to acute liver failure was 23 days, and 16 patients underwent liver transplantation. Final outcome was reported in 58 patients and mortality was 46%. Age was a predictor of poor prognosis in multivariate analysis. No important differences were found between patients infected with genotype 3 vs 4, patients with confirmed vs suspected genotypes, or patients with positive vs negative RNA.

CONCLUSION

Acute liver failure caused by hepatitis E virus genotype 3 and 4 is rare, similar between genotypes, occurs commonly in middle-aged/elderly patients and has a very high mortality. Age is predictive of poor prognosis in multivariate analysis.

A Case of Acute Hepatitis E Infection in a Patient with Non-Hodgkin Lymphoma Treated Successfully with Ribavirin

We present the case of a man who, following immunosuppressive treatment for non-Hodgkin lymphoma, became infected with viral hepatitis E. Acute hepatitis E virus infection should be considered in patients with deranged liver function on a background of haematological malignancies or immunosuppression, even without travel to endemic regions. Whilst clearance is usually spontaneous in immune-competent individuals, these at-risk groups may develop a more complicated and protracted disease course. Thus awareness is important as additional treatment with ribavirin or pegylated interferon may be required, as in this case, in order to help achieve eradication.

Hepatitis E virus seroprevalence among the general population in a livestock-dense area in the Netherlands: a cross-sectional population-based serological survey

Background

Recent serological studies indicate that hepatitis E virus (HEV) is endemic in industrialised countries. The increasing trend in the number of autochthonous cases of HEV genotype 3 in Western European countries, stresses the importance to get insight in the exact routes of exposure. Pigs are the main animal reservoir, and zoonotic food-borne transmission of HEV is proven. However, infected pigs can excrete large amounts of virus via their faeces enabling environmental transmission of HEV to humans. This might pose a risk for of neighbouring residents of livestock farming.

Methods

Within a large study on the health of people living in the vicinity of livestock farming we performed a cross-sectional population-based serological survey among 2,494 non-farming adults from the general population in a livestock-dense area in the south of the Netherlands. Participants completed risk factor questionnaires and blood samples of 2,422 subjects (median age 58 years, range 20–72) were tested for anti-HEV IgG using an enzyme immune assay (Wantai). The aim of this study was to determine the HEV seroprevalence and to assess whether seropositivity in adults was associated with living in the vicinity of pig farms.

Results

The average seroprevalence of HEV was 28.7% (95% CI: 26.9–30.5). Determinants associated with an increased risk for HEV seropositivity were male gender and low level of education. There was a clear trend of increasing prevalence with increasing age (Chi-square test for linear trend, X² = 83.1; p < 0.001). A high number of pigs within 1,000 m of the residential address was not a risk factor for seropositivity.

Conclusions

This study confirmed the high HEV seroprevalence (29%) in the general population of the Netherlands, but presence of antibodies was not associated with residential proximity to pig farms. The prevalence increased with age from 10% in adolescents to 33% among those aged 50 and above, supporting the assumption of a cumulative lifetime exposure to HEV in the Netherlands as well as a higher infection pressure in the past. Our findings cannot refute the assumption that transmission is primarily food-borne.

Role of HEV antigen detection in HEV-related acute viral hepatitis and acute liver failure

Detection of HEV antigen presents as an interesting low cost, novel, and rapid diagnostic technique to ascertain HEV viremia where facilities for reverse transcriptase polymerase chain reaction (RT PCR) are sparse. This study was undertaken to assess the relative efficacy of HEV antigen detection by ELISA with currently available diagnostic tests in patients of HEV-related acute viral hepatitis (AVH) and acute liver failure (ALF). This study included 36 ALF and 64 AVH cases. HEV RNA and HEV viral load were determined by RT PCR and real time PCR, respectively. Evidence of recent HEV infection was detected in 45/64 AVH cases and 22/36 ALF cases. IgM anti-HEV antibody, HEV RNA, and HEV antigen were positive in 34/45 (75.56%), 26/45 (57.77%), and 21/45 (46.66%), in the AVH group, and 16/22 (72.72%), 14/22 (63.63%), 12/22 (54.54%) in ALF group, respectively. The concordance between HEV RNA and HEV antigen was 75.56% (P < 0.01) with κ-coefficient of 0.516 and 75.27% (P = 0.07) with κ-coefficient of 0.441 (P = 0.07) in the AVH and ALF patients, respectively, indicating moderate concordance. It was established that HEV antigen detection can be used as a valuable marker of active viremia and a cheaper surrogate to HEV RT PCR, particularly in window period, pregnant and immunocompromised patients, however, it did not correlate with severity of disease or influence the final outcome of illness in any of the study groups. J. Med. Virol 88:2179-2185, 2016. © 2016 Wiley Periodicals, Inc.

A Proline-Rich Domain in the Genotype 4 Hepatitis E Virus ORF3 C-Terminus Is Crucial for Downstream V105DLP108 Immunoactivity

The hepatitis E virus (HEV) is responsible for serious viral hepatitis worldwide. Animals are considered a reservoir of HEV, particularly pigs. While HEV infection in pigs and dogs is always asymptomatic, the virus causes high death rates in patients with pre-existing chronic liver disease and pregnant women in developing countries. HEV open reading frame 2 (ORF2) has been used as a diagnostic target to detect specific antibodies against HEV in serum samples. Recent research has additionally supported the potential utility of the ORF3 protein as a target in serum anti-HEV detection. However, the epitope distribution of ORF3 protein remains ambiguous. In the current study, we showed that continuous amino acid motif, VDLP, at the C-terminus of genotype 4 HEV ORF3 is a core sequence of the ORF3 protein epitope. Moreover, cooperative interaction with upstream elements is essential for its immunoactivity. Three proline residues (P99, P102 and P103) in the upstream proline-rich domain exerted significant effects on the immunocompetence of VDLP. ELISA results revealed that SAPPLPPVVDLP and SAPPLPPVVDLPQLGL peptides containing the identified VDLP epitope display weaker reactions with anti-HEV serum than the commercial ELISA kit. Our collective findings provide valuable information on the epitope distribution characteristics of HEV ORF3 and improve our understanding of the influence of the proline-rich domain on the immunoactivity of downstream amino acids in the C-terminal region.

Hepatitis E virus infections in humans and animals

Hepatitis E has traditionally been considered an endemic disease of developing countries. It generally spreads through contaminated water. However, seroprevalence studies have shown that hepatitis E virus (HEV) infections are not uncommon in industrialized countries. In addition, the number of autochthonous hepatitis E cases in these countries is increasing. Most HEV infections in developed countries can be traced to the ingestion of contaminated raw or undercooked pork meat or sausages. Several animal species, including pigs, are known reservoirs of HEV that transmit the virus to humans. HEVs are now recognized as an emerging zoonotic agent. In this review, we describe the general characteristics of HEVs isolated from humans and animals, the risk factors for human HEV infection, and the current status of human vaccine development.

An analysis of the benefit of using HEV genotype 3 antigens in detecting anti-HEV IgG in a European population

Background

The benefit of using serological assays based on HEV genotype 3 in industrialised settings is unclear. We compared the performance of serological kits based on antigens from different HEV genotypes.

Methods

Taking 20 serum samples from patients in southwest France with acute HEV infection (positive PCR for HEV genotype 3) and 550 anonymised samples from blood donors in southwest Switzerland, we tested for anti-HEV IgG using three enzyme immunoassays (EIAs) (MP Diagnostics, Dia.Pro and Fortress) based on genotype 1 and 2 antigens, and one immunodot assay (Mikrogen Diagnostik recomLine HEV IgG/IgM) based on genotype 1 and 3 antigens.

Results

All acute HEV samples and 124/550 blood donor samples were positive with ≥1 assay. Of PCR-confirmed patient samples, 45%, 65%, 95% and 55% were positive with MP Diagnostics, Dia.Pro, Fortress and recomLine, respectively. Of blood donor samples positive with ≥1 assay, 120/124 (97%), were positive with Fortress, 19/124 (15%) were positive with all EIAs and 51/124 (41%) were positive with recomLine. Of 11/20 patient samples positive with recomLine, stronger reactivity for HEV genotype 3 was observed in 1/11(9%), and equal reactivity for both genotypes in 5/11 (45.5%).

Conclusions

Although recomLine contains HEV genotype 3, it has lower sensitivity than Fortress in acute HEV infection and fails to identify infection as being due to this genotype in approximately 45% of patients. In our single blood donor population, we observe wide variations in measured seroprevalence, from 4.2% to 21.8%, depending on the assay used.

Serological investigation for hepatitis E virus infection in the patients with chronic maintenance hemodialysis from southwest of Iran

BACKGROUND AND OBJECTIVES

A global distribution has been shown for hepatitis E virus (HEV) infection. Although the fecal-oral was considered as the primary infection route, there is controversial evidence for increased risk of the infection and consequent problems in patients on maintenance hemodialysis (HD) with suppressed immunity. The aim is to find if the prevalence of anti-HEV IgG, in patients with maintenance HD is higher than normal population in southwest of Iran.

MATERIALS AND METHODS

During November and December 2010, in a cross-sectional study we compared the seroprevalence of HEV among 80 patients with maintenance HD and 276 healthy individuals from Jahrom and Shiraz, Southwest of Iran. In addition to the clinical and laboratory records, serum samples were tested for the presence of IgG anti-HEV antibody by enzyme immunoassay (ELISA) test. The Chi-square, the Student's 't' and Fisher's exact tests were used for the statistical analysis.

RESULTS

ELISA tests detected anti-HEV antibody in five males of the patients (6.3%) and in eight of the healthy controls (2.9%, 6 males and 2 female) which statistically were not different. The mean levels of the aspartate aminotransferase and the alanine aminotransferase in the sera of the patients were 19.96±11.08U/L and 23.93±14.26 IU/L, respectively. However, no one of the individuals with positive anti-HEV antibody showed elevated liver enzymes. Moreover, there was not a significant association between positive anti-HEV antibody result, age and the history of the hemodialysis.

CONCLUSIONS

We did not observe statistically significant higher anti-HEV prevalence among patients with chronic HD; however, more safety precaution is needed to keep HD patients from the risk of possible exposure to HEV infection.

The global burden of hepatitis E virus genotypes 1 and 2 in 2005

We estimated the global burden of hepatitis E virus (HEV) genotypes 1 and 2 in 2005. HEV is an emergent waterborne infection that causes source-originated epidemics of acute disease with a case fatality rate thought to vary by age and pregnancy status. To create our estimates, we modeled the annual disease burden of HEV genotypes 1 and 2 for 9 of 21 regions defined for the Global Burden of Diseases, Injuries, and Risk Factors Study (the GBD 2010 Study), which represent 71% of the world's population. We estimated the seroprevalence of anti-HEV antibody and annual incidence of infection for each region using data from 37 published national studies and the DISMOD 3, a generic disease model designed for the GBD Study. We converted incident infections into three mutually exclusive results of infection: (1) asymptomatic episodes, (2) symptomatic disease, and (3) death from HEV. We also estimated incremental cases of stillbirths among infected pregnant women. For 2005, we estimated 20.1 (95% credible interval [Cr.I.]: 2.8-37.0) million incident HEV infections across the nine GBD Regions, resulting in 3.4 (95% Cr.I.: 0.5-6.5) million symptomatic cases, 70,000 (95% Cr.I.: 12,400-132,732) deaths, and 3,000 (95% Cr.I.: 1,892-4,424) stillbirths. We estimated a probability of symptomatic illness given infection of 0.198 (95% Cr.I.: 0.167-0.229) and a probability of death given symptomatic illness of 0.019 (95% Cr.I.: 0.017-0.021) for nonpregnant cases and 0.198 (95% Cr.I.: 0.169-0.227) for pregnant cases.

CONCLUSION

The model was most sensitive to estimates of age-specific incidence of HEV disease.

Prevalence of hepatitis E virus-specific antibodies in humans with occupational exposure to pigs

Due to the increasing number of non-travel-associated hepatitis E virus (HEV) infections observed in several industrialised countries including Germany, there is a substantial interest in the characterisation of risk factors and transmission routes relevant to autochthonous HEV infections. Autochthonous cases are believed to be the result of a zoonotic HEV transmission from pigs, wild boars and deer. Recently, a high prevalence of HEV-specific antibodies in the German domestic pig population has been demonstrated. Thus, one may assume a higher prevalence of HEV-specific antibodies in humans with occupational exposure to pigs. In this study, sera obtained from 24 slaughterers, 14 meat inspectors, 46 pig farmers and 22 veterinarians were tested for the presence of HEV-specific antibodies using a line immunoassay. For comparison, sera obtained from 116 age- and gender-matched blood donors were also included. Twenty eight per cent (28.3%; 30/106) of the swine-exposed humans and 15.5% (18/116) of the blood donors without contact to pigs exhibited IgG-antibodies determined as reactive (i.e. borderline or positive) against HEV. Thus, an increased risk of HEV infection in humans occupationally exposed to pigs and particularly for slaughterers (41.7%; 10/24) was demonstrated.

[Chronic hepatitis E in an immunocompetent patient]

Hepatitis E virus (HEV) is a Herpesvirus, with four different genotypes. Genotypes 1 and 2 often cause acute hepatitis, which presents as outbreaks in endemic regions of Asia and Africa. Genotypes 3 and 4 cause sporadic cases of acute hepatitis in Europe and North America, where it is considered a zoonosis. Symptoms usually resolve spontaneously, but in recent years cases have been detected that progress to chronic liver disease mainly in immunocompromised patients (patients with solid organ transplants, lymphoma, human immunodeficiency virus, primary immunodeficiencies, and those under treatment with corticosteroids and immunosuppressive agents..). We report the case of a healthy, immunocompetent man who developed an episode of acute HEV hepatitis, which progressed to chronic liver disease with fibrosis grade III/IV in the liver biopsy within a year and half.

[Chronic hepatitis E]

The hepatitis E virus is an RNA virus with 4 genotypes. Genotypes 1 and 2 only affect humans and produce epidemic acute hepatitis in endemic regions (Asia and Africa). Genotypes 3 and 4 are considered a zoonosis and produce episodic acute hepatitis in non-endemic areas (America and Europe). However, in the last 3 years there have been cases of chronic HEV hepatitis, mainly in immunosuppressed patients. Here we review the known data of chronic hepatitis E in terms of evolution and treatment.