Absence of chronic hepatitis E virus infection in liver transplant recipients: Report from a hyperendemic region

The Risk of Reinfection or Primary Hepatitis E Virus Infection at a Liver Transplant Center in Brazil: An Observational Cohort Study

The hepatitis E virus is a major etiological agent of chronic hepatitis in immunosuppressed individuals. Seroprevalence in the liver transplantation setting varies according to the seroprevalence of the general population in different countries. This was a prospective cohort study of liver transplant recipients in southeastern Brazil. Recipients were systematically followed for one year, with the objective of determining the prevalence, incidence, and natural history of HEV infection in this population. We included 107 liver transplant recipients and 83 deceased donors. Positivity for anti-HEV IgG was detected in 10.2% of the recipients and in 9.7% of the donors. None of the patients tested positive for HEV RNA at baseline or during follow-up. There were no episodes of reactivation or seroconversion, even in cases of serological donor-recipient mismatch or in recipients with acute hepatitis. Acute and chronic HEV infections seem to be rare events in the region studied. That could be attributable to social, economic, and environmental factors. Our data indicate that, among liver transplant recipients, hepatitis E should be investigated only when there are elevated levels of transaminases with no defined cause, as part of the differential diagnosis of seronegative hepatitis after transplantation.

Epidemiology and treatment of hepatitis E in the liver transplantation setting: A literature review

Hepatitis E virus (HEV) is a common cause of acute hepatitis in developing countries, but it can also take a chronic course especially in immunocompromised patients. Its epidemiology after liver transplantation (LT) is hard to assess and treatment options are still explored. Between 2009 and 2020, literature reporting HEV prevalence and treatment in LT recipients was searched and a synthesis was attempted. Sixteen studies reported HEV prevalence in consecutive LT patients: HEV RNA positivity ranged between 0%-1.4% and 0%-7.7% for Western and Eastern cohorts, respectively. In studies published between 2009-2014 and 2015-2020, HEV RNA positivity ranged between 0.35%-1.3% (all European) and 0%-7.7% (European: 0%-1.4%), respectively. Five studies evaluated HEV prevalence in LT recipients with abnormal liver enzymes: HEV RNA positivity was 2.9% in studies published between 2009 and 2014 and from 3.5% to 20% in studies published between 2015 and 2020. Twenty-seven studies reported HEV treatment in LT recipients: sustained virologic response was achieved in 15% by immunosuppression reduction alone and in 83% of cases by ribavirin regiments. Chronic HEV infection is affecting LT recipients, mostly those with abnormal liver enzymes and in Eastern countries. HEV diagnoses should be based on PCR techniques. Successful treatment can be achieved with ribavirin in most cases.

Sofosbuvir in the Treatment of Hepatitis E virus Infection: A Review of in vitro and in vivo Evidence

Chronic hepatitis E virus (HEV) infection, which occurs almost exclusively in immunocompromised patients, if untreated may progress to cirrhosis and possibly hepatocellular carcinoma. The reduction of immunosuppression and/or administration of ribavirin is frequently curative but there remain many immunocompromised individuals whose HEV infection is refractory to these therapeutic strategies. Moreover, the haematological toxicity of ribavirin limits its use. Pegylated interferon has demonstrated success in a small number of patients with chronic HEV infection; however, the potentially increased risk of graft rejection associated with its use renders it unsuitable for many transplant recipients. Alternative therapeutic strategies are therefore required. This article reviews the in vitro and in vivo literature to date of the antiviral agent sofosbuvir (well established in the treatment of hepatitis C) in the treatment of HEV infection.

Viral Hepatitis E and Chronicity: A Growing Public Health Concern

Hepatitis E viral infection recently emerges as a global health concern. Over the last decade, the understanding of hepatitis E virus (HEV) had changed with the discovery of new genotypes like genotype-7 and genotype-8 with associated host and mode of infection. Diversification in the mode of hepatitis E infection transmission through blood transfusion, and organ transplants in contrast to classical feco-oral and zoonotic mode is the recent medical concern. The wide spectrum of infection ranging from self-limiting to acute liver failure is now overpowered by HEV genotype-specific chronic infection especially in transplant patients. This concern is further escalated by the extra-hepatic manifestations of HEV targeting the central nervous system (CNS), kidney, heart, and pancreas. However, with the development of advanced efficient cell culture systems and animal models simulating the infection, much clarity toward understanding the pathogenetic mechanism of HEV has been developed. Also this facilitates the development of vaccines research or therapeutics. In this review, we highlight all the novel findings in every aspect of HEV with special emphasis on recently emerging chronic mode of infection with specific diagnosis and treatment regime with an optimistic hope to help virologists and/or liver specialists working in the field of viral hepatitis.

Hepatitis E virus infection in liver transplant recipients: a descriptive literature review

Hepatitis E virus infection has been recognized as a rising hepatotropic viral infection in the developing countries but overlooked in the developed countries, due to its lower prevalence. However, hepatitis E virus prevalence is on rise in the liver transplant recipients due to immunosuppression, which needs prompt recognition by healthcare practitioners. Hepatitis E virus infection is commonly believed to be transmitted via an animal host; but in the post-liver transplant patients, it can also be acquired via blood and blood products transfusion and autochthonous route. Previous studies have shown the significance of hepatitis E virus infection in post-liver transplant, as the patients at a high risk of progressing to chronic hepatitis and cirrhosis. Pediatric patients are at higher risk of hepatitis E virus infection post-liver transplant. Specific hepatitis E virus genotypes have the potential for greater severity. The clinical manifestation of hepatitis E virus can also present as extrahepatic features which need high level of suspicion for early recognition and treatment. Treatment options of hepatitis E virus range from immunosuppressive drug minimization, ribavirin therapy to novel direct-acting antiviral regimens. Herein, we aim to explore epidemiology, prevalence, risk factor, diagnosis, and management of hepatitis E virus infection giving special attention to liver transplant recipients.

Temporal profile of HEV RNA concentration in blood and stool from patients with acute uncomplicated hepatitis E in a region with genotype 1 predominance

Acute hepatitis E virus (HEV) is associated with viremia and faecal excretion of the virus. The information on duration and temporal pattern of viremia and faecal shedding in HEV infection is important, but is not available. Serial serum and stool specimens were collected from patients with acute hepatitis E (typical clinical picture, serum alanine aminotransferase levels > 5-folds the upper limit of normal and presence of IgM anti-HEV), beginning from within 7 days of the onset of symptoms. HEV RNA concentrations were measured in sera and 10% stool suspensions, using a real-time Taqman-based nucleic acid amplification assay. Seventeen patients (median age 25 [range 19-61] years; all men) were enrolled within a median of 5 (range 3-8) days of the onset of the first symptom and provided 113 serum specimens and 71 stool specimens. The median (range) highest levels of serum bilirubin, alanine aminotransferase and aspartate aminotransferase in the patients were 10.3 (5.9-43.4) mg/dL, 1817 (442-4642) IU/L and 1016 (88-4561) IU/L, respectively. All the 17 patients had demonstrable viremia, and 12 of the 13 patients who were tested had faecal excretion at one or more time points. The HEV RNA titres were the highest in the early phase of disease and declined rapidly with time, becoming nondetectable in the serum by day 20 and in the stool by day 21. In most of the patients with acute uncomplicated acute hepatitis E, the degree of viremia and faecal shedding decline quickly after the onset of clinical illness and rapidly disappear in parallel with each other.

Hepatitis E: an expanding epidemic with a range of complications

BACKGROUND

Hepatitis E virus (HEV) is a common cause of viral hepatitis worldwide. Previously considered a disease of the developing world, it is increasingly recognized that locally acquired HEV infection is common in industrialized countries.

OBJECTIVES

The aim was to highlight the changing epidemiology of HEV infection, particularly in the developed world, and inform clinicians of the diverse clinical presentations and extra-hepatic complications associated with the virus.

SOURCES

References for this review were identified through searches of MEDLINE/PubMed, and Google Scholar, up to January 2020. Searches were restricted to articles published in English.

CONTENT

Hepatitis E virus is an under-recognized, emerging pathogen with important implications for public health in both the developing and developed world. The number of cases reported in resource-rich settings is increasing, in part due to improved case ascertainment but also as a result of increased incidence in some countries. The reasons behind these epidemiological shifts are not currently known. Chronic HEV infection has been reported in immunocompromised patients. A range of extra-hepatic manifestations have also been reported, most notably neurological and renal complications. There is evidence to suggest a causal link with Guillain-Barré syndrome, neuralgic amyotrophy and encephalitis/myelitis. Glomerular disease has been reported in the context of both acute and chronic infection.

IMPLICATIONS

HEV should be included in non-invasive liver screens and considered in the differentials for patients presenting with alanine aminotransferase elevation, suspected drug-induced liver injury or decompensated liver disease. Any patients with acute neurological injury and deranged liver function should be tested for hepatitis E, and all patients presenting with Guillain-Barré syndrome or neuralgic amyotrophy should be tested regardless of liver enzymes. Immunocompromised patients with persistently raised liver enzymes should be tested with molecular techniques and offered annual routine screening.

Prevalence of hepatitis E viraemia among blood donors: a systematic review

BACKGROUND

Hepatitis E virus (HEV) is usually transmitted by faecal-oral route. Recent reports have documented HEV viraemia in donated blood units and HEV transmission through blood transfusion. This systematic review summarizes the available data on prevalence of HEV viraemia in blood donors.

METHODS

Electronic databases were searched on 17 December 2018 to identify full-text English papers reporting original data on prevalence of HEV RNA in donated blood units. Two authors independently extracted the relevant data, which were pooled using simple aggregation as well as a random-effects meta-analysis; heterogeneity was assessed using the I2 method.

RESULTS

In all, 59 data sets from 28 countries were identified. The available data showed marked heterogeneity. Of a total of 2 127 832 units studied, 561 (263·6 [95% confidence intervals = 242·7-286·4] per million units) tested positive for HEV RNA. On random-effects meta-analysis, the pooled prevalence was 60·9 [6·7-155·4] per million units. In the viraemic units, HEV RNA titre varied by nearly one million-fold, and most had genotype 3 HEV. The prevalence was higher in blood units with anti-HEV antibodies or elevated alanine aminotransferase. Only nearly one-fourth of viraemic units had anti-HEV antibodies.

CONCLUSIONS

The prevalence of HEV viraemia among healthy blood donors is low, though the available data had limited geographical representation and marked heterogeneity. There is a need for further data on HEV viraemia in blood donors from areas with non-3 HEV genotype preponderance.

The Clinical Perspective on Hepatitis E

Every year, there are an estimated 20 million hepatitis E virus (HEV) infections worldwide, leading to an estimated 3.3 million symptomatic cases of hepatitis E. HEV is largely circulating in the west and is associated with several hepatic and extrahepatic diseases. HEV Genotype 1 and 2 infections are waterborne and causative for epidemics in the tropics, while genotype 3 and 4 infections are zoonotic diseases and are mainly transmitted by ingestion of undercooked pork in industrialized nations. The clinical course of these infections differs: genotype 1 and 2 infection can cause acute illness and can lead to acute liver failure (ALF) or acute on chronic liver failure (ACLF) with a high mortality rate of 20% in pregnant women. In contrast, the majority of HEV GT-3 and -4 infections have a clinically asymptomatic course and only rarely lead to acute on chronic liver failure in elderly or patients with underlying liver disease. Immunosuppressed individuals infected with genotype 3 or 4 may develop chronic hepatitis E, which then can lead to life-threatening cirrhosis. Furthermore, several extra-hepatic manifestations affecting various organs have been associated with ongoing or previous HEV infections but the causal link for many of them still needs to be proven. There is no approved specific therapy for the treatment of acute or chronic HEV GT-3 or -4 infections but off-label use of ribavirin has been demonstrated to be safe and effective in the majority of patients. However, in approximately 15% of chronically HEV infected patients, cure is not possible.

Prevalence of hepatitis E virus viremia and antibodies among healthy blood donors in India

BACKGROUND

Hepatitis E virus (HEV) is transmitted primarily through contaminated water and food. Recently, HEV viremia in blood donors and transfusion-related transmission of HEV have been reported, leading to calls to screen donated blood for this virus. However, these data are from regions where genotype 3 HEV is predominant. In India, where human infections are caused only by genotype 1 HEV, the frequency of subclinical HEV viremia is unknown.

METHODS

Minipools of sera prepared from three donor units each from our institution's  blood bank in Lucknow, India, were tested for HEV RNA using a sensitive amplification-based assay. A randomly selected subset was also tested for IgG anti-HEV antibodies using a commercial (Wantai) immunoassay.

RESULTS

Sera from 1799 donors (median [range] age 30 [18-63] years; 1746 [97.0%] men) were collected (June-July 2016, 900; November-December 2016, 899). Of these, 17 (0.95%), 16 (0.90%), and 3 (0.17%) tested positive for HBsAg, anti-HCV, and anti-HIV antibodies, respectively. None of the donors tested positive for HEV RNA. Of 633 randomly selected donors (age 30 [18-63] years, 613 [96.8%] male) tested for IgG anti-HEV, 383 (60.5%) tested positive. Seropositivity rate increased with age, being 70/136 (52%), 177/299 (59%), 100/154 (65%), 30/34 (88%), and 6/10 (60%) in the 18-24, 25-34, 35-44, 45-54, and 55 years or older age groups, respectively.

CONCLUSIONS

In healthy blood donors from northern India, HEV viremia is infrequent though anti-HEV antibody prevalence is high. This suggests that asymptomatic HEV viremia may be less frequent in areas with genotype 1 predominance than those with genotype 3 predominance.