Fatal outcome of autochthonous hepatitis E in a patient with B cell lymphoma in Southeastern France

Case Report: Chronic hepatitis E in a hematopoietic stem cell transplant recipient: The first report of hepatitis E virus genotype 4 causing chronic infection in a non-solid organ recipient

Hepatitis E virus (HEV) is one of the most important public health issues around the world, and chronic HEV infection has been reported in immunosuppressed individuals. This study reported a male case, with very severe aplastic anemia (AA), who developed chronic hepatitis E after hematopoietic stem cell transplantation (HSCT). Abnormal alanine aminotransferase (ALT) appeared after HSCT and persisted for twenty-nine months. The case was seropositive for anti-HEV IgG and IgM after HSCT. Twenty-two months after HSCT, HEV RNA and antigen (Ag) testing were positive and persisted for five and seven months, respectively. Positive stains of HEV Ag were present in a liver biopsy sample. HEV Ag was present in bone marrow. The individual rapidly developed liver cirrhosis and was rescued by a regimen of oral ribavirin. These factors suggested there is a risk of HEV infection in HSCT recipients.

Hepatitis E Virus Infection-Immune Responses to an Underestimated Global Threat

Infection with the hepatitis E virus (HEV) is one of the main ubiquitous causes for developing an acute hepatitis. Moreover, chronification plays a predominant role in immunocompromised patients such as transplant recipients with more frequent severe courses. Unfortunately, besides reduction of immunosuppression and off-label use of ribavirin or pegylated interferon alfa, there is currently no specific anti-viral treatment to prevent disease progression. So far, research on involved immune mechanisms induced by HEV is limited. It is very difficult to collect clinical samples especially from the early phase of infection since this is often asymptomatic. Nevertheless, it is certain that the outcome of HEV-infected patients correlates with the strength of the proceeding immune response. Several lymphoid cells have been identified in contributing either to disease progression or achieving sustained virologic response. In particular, a sufficient immune control by both CD4⁺ and CD8⁺ T cells is necessary to prevent chronic viral replication. Especially the mechanisms underlying fulminant courses are poorly understood. However, liver biopsies indicate the involvement of cytotoxic T cells in liver damage. In this review, we aimed to highlight different parts of the lymphoid immune response against HEV and point out questions that remain unanswered regarding this underestimated global threat.

The burden of hepatitis E among patients with haematological malignancies: A retrospective European cohort study

BACKGROUND & AIMS

The burden of hepatitis E virus (HEV) infection among patients with haematological malignancy has only been scarcely reported. Therefore, we aimed to describe this burden in patients with haematological malignancies, including those receiving allogeneic haematopoietic stem cell transplantation.

METHODS

We conducted a retrospective, multicentre cohort study across 11 European centres and collected clinical characteristics of 50 patients with haematological malignancy and RNA-positive, clinically overt hepatitis E between April 2014 and March 2017. The primary endpoint was HEV-associated mortality; the secondary endpoint was HEV-associated liver-related morbidity.

RESULTS

The most frequent underlying haematological malignancies were aggressive non-Hodgkin lymphoma (NHL) (34%), indolent NHL (iNHL) (24%), and acute leukaemia (36%). Twenty-one (42%) patients had received allogeneic haematopoietic stem cell transplantation (alloHSCT). Death with ongoing hepatitis E occurred in 8 (16%) patients, including 1 patient with iNHL and 1 patient >100 days after alloHSCT in complete remission, and was associated with male sex (p = 0.040), cirrhosis (p = 0.006) and alloHSCT (p = 0.056). Blood-borne transmission of hepatitis E was demonstrated in 5 (10%) patients, and associated with liver-related mortality in 2 patients. Hepatitis E progressed to chronic hepatitis in 17 (34%) patients overall, and in 10 (47.6%) and 6 (50%) alloHSCT and iNHL patients, respectively. Hepatitis E was associated with acute or acute-on-chronic liver failure in 4 (8%) patients with 75% mortality. Ribavirin was administered to 24 (48%) patients, with an HEV clearance rate of 79.2%. Ribavirin treatment was associated with lower mortality (p = 0.037) and by trend with lower rates of chronicity (p = 0.407) when initiated <24 and <12 weeks after diagnosis of hepatitis E, respectively. Immunosuppressive treatment reductions were associated with mortality in 2 patients (28.6%).

CONCLUSION

Hepatitis E is associated with mortality and liver-related morbidity in patients with haematological malignancy. Blood-borne transmission contributes to the burden. Ribavirin should be initiated early, whereas reduction of immunosuppressive treatment requires caution.

LAY SUMMARY

Little is known about the burden of hepatitis E among patients with haematological malignancy. We conducted a retrospective European cohort study among 50 patients with haematological malignancy, including haematopoietic stem cell transplant recipients, with clinically significant HEV infection and found that hepatitis E is associated with hepatic and extrahepatic mortality, including among patients with indolent disease or among stem cell transplant recipients in complete remission. Hepatitis E virus infection evolved to chronic hepatitis in 5 (45.5%) patients exposed to a rituximab-containing regimen and 10 (47.6%) stem cell transplant recipients. Reducing immunosuppressive therapy because of hepatitis E was associated with mortality, while early ribavirin treatment was safe and effective.

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.

Hepatitis E in High-Income Countries: What Do We Know? And What Are the Knowledge Gaps?

Hepatitis E virus (HEV) is a positive-strand RNA virus transmitted by the fecal–oral route. HEV genotypes 1 and 2 infect only humans and cause mainly waterborne outbreaks. HEV genotypes 3 and 4 are widely represented in the animal kingdom, and are mainly transmitted as a zoonosis. For the past 20 years, HEV infection has been considered an imported disease in developed countries, but now there is evidence that HEV is an underrecognized pathogen in high-income countries, and that the incidence of confirmed cases has been steadily increasing over the last decade. In this review, we describe current knowledge about the molecular biology of HEV, its clinical features, its main routes of transmission, and possible therapeutic strategies in developed countries.

Public health risks associated with hepatitis E virus (HEV) as a food-borne pathogen

Hepatitis E virus (HEV) is an important infection in humans in EU/EEA countries, and over the last 10 years more than 21,000 acute clinical cases with 28 fatalities have been notified with an overall 10-fold increase in reported HEV cases; the majority (80%) of cases were reported from France, Germany and the UK. However, as infection in humans is not notifiable in all Member States, and surveillance differs between countries, the number of reported cases is not comparable and the true number of cases would probably be higher. Food-borne transmission of HEV appears to be a major route in Europe; pigs and wild boars are the main source of HEV. Outbreaks and sporadic cases have been identified in immune-competent persons as well as in recognised risk groups such as those with pre-existing liver damage, immunosuppressive illness or receiving immunosuppressive treatments. The opinion reviews current methods for the detection, identification, characterisation and tracing of HEV in food-producing animals and foods, reviews literature on HEV reservoirs and food-borne pathways, examines information on the epidemiology of HEV and its occurrence and persistence in foods, and investigates possible control measures along the food chain. Presently, the only efficient control option for HEV infection from consumption of meat, liver and products derived from animal reservoirs is sufficient heat treatment. The development of validated quantitative and qualitative detection methods, including infectivity assays and consensus molecular typing protocols, is required for the development of quantitative microbial risk assessments and efficient control measures. More research on the epidemiology and control of HEV in pig herds is required in order to minimise the proportion of pigs that remain viraemic or carry high levels of virus in intestinal contents at the time of slaughter. Consumption of raw pig, wild boar and deer meat products should be avoided.

Hepatitis E Virus in Industrialized Countries: The Silent Threat

Hepatitis E virus (HEV) is the main cause of acute viral hepatitis worldwide. Its presence in developing countries has been documented for decades. Developed countries were supposed to be virus-free and initially only imported cases were detected in those areas. However, sporadic and autochthonous cases of HEV infection have been identified and studies reveal that the virus is worldwide spread. Chronic hepatitis and multiple extrahepatic manifestations have also been associated with HEV. We review the data from European countries, where human, animal, and environmental data have been collected since the 90s. In Europe, autochthonous HEV strains were first detected in the late 90s and early 2000s. Since then, serological data have shown that the virus infects quite frequently the European population and that some species, such as pigs, wild boars, and deer, are reservoirs. HEV strains can be isolated from environmental samples and reach the food chain, as shown by the detection of the virus in mussels and in contaminated pork products as sausages or meat. All these data highlight the need of studies directed to control the sources of HEV to protect immunocompromised individuals that seem the weakest link of the HEV epidemiology in industrialized regions.

Epidemiology of Hepatitis E Virus in European Countries

Over the last decade the seroprevalence of immunoglobulin (IgG) anti hepatitis E virus (HEV) has been increasing in European countries and shows significant variability among different geographical areas. In this review, we describe the serological data concerning the general population and risk groups in different European countries. Anti-HEV antibody prevalence ranged from 1.3% (blood donors in Italy) to 52% (blood donors in France). Various studies performed on risk groups in Denmark, Moldova and Sweden revealed that swine farmers have a high seroprevalence of HEV IgG (range 13%-51.1%), confirming that pigs represent an important risk factor in HEV infection in humans. Subtypes 3e,f are the main genotypes detected in the European population. Sporadic cases of autochthonous genotype 4 have been described in Spain, France, and Italy. Although most HEV infections are subclinical, in immune-suppressed and transplant patients they could provoke chronic infection. Fulminant hepatitis has rarely been observed and it was related to genotype 3. Interferon and ribavirin treatment was seen to represent the most promising therapy.

Hepatitis E Virus of Subtype 3a in a Pig Farm, South-Eastern France

Hepatitis E virus (HEV) has emerged during the past decade as a causative agent of autochthonous hepatitis and is a clinical concern in Western developed countries. It has been increasingly recognized that pigs are a major reservoir of HEV of genotypes 3 and 4 worldwide and pig-derived food items represent a potential source of infections by these viruses in humans. Hepatitis E virus RNA testing was performed here on faeces from rectal swabs sampled in 2012 from 50 3-month-old farm pigs from the same farm located in south-eastern France than in a previous work conducted in 2007. Pig HEV sequences corresponding to genomic fragments of ORF2 and ORF1 genes were obtained after RT-PCR amplification with in-house protocols. Hepatitis E virus genotype was determined by phylogenetic analysis. Prevalence was similar to that determined 5 years earlier (68% versus 62%). Two robust phylogenetic clusters of HEV subtypes 3a and 3f were identified, and these sequences obtained in 2012 largely differ compared with those obtained in 2007. Notably, HEV sequences obtained in 2012 from a majority (62%) of the infected pigs belonged to subtype 3a, which was not previously described in France, including not being found in any of humans, pigs or wild boars. Further studies are needed to assess the circulation of HEV-3a in pigs and humans in this country. In addition, along with previous findings, this study supports the need for increased information to the public on the risk of HEV infection through contacts with pigs or consumption of pig-derived products in France.