Efficacy and safety of ribavirin therapy for chronic hepatitis E after kidney transplantation

Hepatitis E virus (HEV) infection has been recognized as an acute condition. However, recent reports have shown that immunocompromised patients, such as those receiving solid‐organ transplantation, can develop chronic hepatitis with HEV infection. We report two cases of chronic hepatitis E after kidney transplantation (KT) who were successfully treated with ribavirin monotherapy. Several years after KT, both patients had sustained elevations in the levels of liver enzymes for a period of more than 6 months. Both patients had HEV infection, genotype 3a. Histological studies showed infiltration of inflammatory cells without fibrosis. Treatment included ribavirin monotherapy at a dosage of 600 mg daily for 3 months. One month after therapy initiation, HEV‐RNA turned to negative, and remained negative at 24 weeks after ribavirin therapy without severe complications. Although the treatment of chronic hepatitis E is not fully established, ribavirin therapy can be a safe and effective treatment for chronic hepatitis E.     

Clinical features and determinants of chronicity in hepatitis E virus infection

Hepatitis E virus (HEV) has traditionally been associated with an acute, self‐limiting hepatitis and is not known to have any chronic sequelae. HEV genotypes 1 and 2, which are human pathogens, have been associated with this self‐limiting presentation, in both sporadic and epidemic settings. HEV genotype 3, which is zoonotically transmitted, is increasingly being reported as a cause of chronic infection in immunocompromised patients. These include patients with solid organ transplants, patients receiving chemotherapy for haematologic malignancies and patients infected with HIV. Chronic infection is associated with rapidly progressing liver disease and extrahepatic manifestations including neurologic disorders. We review the clinical manifestations of chronic HEV infection and discuss factors determining persistence and chronicity of HEV.     

Lack of evidence of hepatitis E virus infection among renal transplant recipients in a disease‐endemic area

Persistent hepatitis E virus (HEV) infection has been reported among solid‐organ transplant recipients in nonendemic areas. Such chronic infections have all been related to genotype 3 HEV, which is prevalent in these areas. Whether persistent infection occurs with genotype 1 HEV, prevalent in areas where the infection is hyperendemic, is unclear. We therefore tested sera from renal transplant recipients receiving immunosuppressive agents in India, where genotype 1 HEV infection is endemic, for alanine aminotransferase levels, and presence of IgM and IgG anti‐HEV antibodies and HEV RNA. Of the 205 subjects studied [aged 16–65 (median, 38) years, 182 male], 46 (22.4%) had abnormal ALT levels (>40 IU/mL). IgG anti‐HEV was detected in 52 (20.5%) and IgM anti‐HEV was detected in 14 (6.8%) subjects, including four who had IgG anti‐HEV; antibody positivity had no relation with serum ALT or serum creatinine. All the sera tested were negative for HEV RNA. These findings suggest that chronic infection with genotype 1 HEV is infrequent.     

Hepatitis E in immunocompromised individuals

Hepatitis E virus (HEV) originally identified as a cause of acute icteric hepatitis in developing countries has grown to be a cause of zoonotic viral hepatitis in developed countries such as the United States. While there are eight identified genotypes to date, genotype 1 (HEV1), HEV2, HEV3, HEV4 are the most common to infect humans. HEV1 and HEV2 are most common in developing countries including Latina America, Africa and Asia, and are commonly transmitted through contaminated water supplies leading to regional outbreaks. In contrast HEV3 and HEV4 circulate freely in many mammalian animals and can lead to occasional transmission to humans through fecal contamination or consumption of undercooked meat. The incidence and prevalence of HEV in the United States is undetermined given the absence of FDA approved serological assays and the lack of commercially available testing. In majority of cases, HEV infection is a self-limiting hepatitis requiring only symptomatic treatment. However, this is not the case in immunocompromised individuals, including those that have undergone solid organ or stem cell transplantation. In this subset of patients, chronic infection can be life threatening as hepatic insult can lead to inflammation and fibrosis with subsequent cirrhosis and death. The need for re-transplantation as a result of post-transplant hepatitis is of great concern. In addition, there have been many reported incidents of extrahepatic manifestations, for which the exact mechanisms remain to be elucidated. The cornerstone of treatment in immunocompromised solid organ transplant recipients is reduction of immunosuppressive therapies, while attempting to minimize the risk of organ rejection. Subsequent treatment options include ribavirin, and pegylated interferon alpha in those who have demonstrated ribavirin resistance. Further investigation assessing safety and efficacy of anti-viral therapy is imperative given the rising global health burden. Given this concern, vaccination has been approved in China with other investigations underway throughout the world. In this review we introduce the epidemiology, diagnosis, clinical manifestations, and treatment of HEV, with emphasis on immunocompromised individuals in the United States.     

Viral RNA but no evidence of replication can be detected in the peripheral blood mononuclear cells of hepatitis E virus–infected patients

Summary. Hepatitis E virus (HEV) infection is an important cause of acute viral hepatitis in several developing countries but has recently been shown to cause chronic hepatitis in immunosuppressed persons. Other hepatotropic viruses that cause chronic infection have been shown to infect peripheral blood mononuclear cells (PBMCs) and to persist in those cells. We therefore decided to look for evidence of replication of HEV in PBMCs obtained from patients with acute hepatitis E, using strand‐specific assays for positive and negative HEV RNA. Of the 44 patients with acute hepatitis E during an outbreak in India, including 27 with detectable IgM anti‐HEV and 19 with detectable serum HEV RNA, 11 had detectable HEV RNA in their PBMCs. However, of the six PBMC specimens with strong HEV RNA signal, none had detectable negative‐strand HEV RNA, a marker of viral replication. These findings indicate the presence of HEV RNA but the absence of its replication in PBMCs from patients with acute hepatitis E.     

Hepatitis E: an emerging global disease – from discovery towards control and cure

Hepatitis E is a systemic disease affecting the liver predominantly and caused by infection with the hepatitis E virus (HEV). HEV has marked genetic heterogeneity and is known to infect several animal species including pigs, boar, deer, mongoose, rabbit, camel, chicken, rats, ferret, bats and cutthroat trout. HEV is the sole member of the family Hepeviridae and has been divided into 2 genera: Orthohepevirus (mammalian and avian HEV) and Piscihepevirus (trout HEV). Human HEVs included within the genus Orthohepevirus are designated Orthohepevirus A (isolates from human, pig, wild boar, deer, mongoose, rabbit and camel). Hepatitis E is an important public health concern, and an estimated one‐third of the world population has been infected with HEV. In recent years, autochthonous hepatitis E is recognized as a clinical problem in industrialized countries. Several animal species especially domestic swine, wild boar and wild deer are reservoirs of genotype HEV‐3 and HEV‐4 in these countries. Human infections occur through intake of uncooked or undercooked meat of the infected animals and pig livers or sausages made from these livers and sold in supermarkets. HEV can be transmitted through blood and blood component transfusions, and donor screening for HEV is under serious consideration. Chronic hepatitis E resulting in rapidly progressive liver cirrhosis and end‐stage liver disease has been described in organ transplant patients. Ribavirin monotherapy attains sustained virological response in most patients. HEV 239 vaccine has been marketed in China and its long‐term efficacy over four and a half years reported.     

Acute hepatitis E virus infection causing acute liver failure requiring living‐donor liver transplantation in a non‐pregnant immunocompetent woman

We report a rare case of acute liver failure from acute hepatitis E virus (HEV) in a non‐pregnant woman without comorbidities who survived after liver transplantation. The source was likely consumption of partially cooked pig liver. HEV genotype 3 is the second most common genotype causing acute hepatitis E in developed countries. Fulminant hepatitis E rarely occurs without a risk factor, as in our patient. Vigilant monitoring for chronic hepatitis E in post‐transplant immunocompromised patients is needed.     

慢性戊型肝炎的研究进展

戊型肝炎病毒(hepatitis E virus,HEV)引起的戊型肝炎一直被认为是一种急性自限性感染过程,然而最近发现,器官移植、人类免疫缺陷病毒(human immunodeficiency virus,HIV)感染者等免疫力低下的患者感染HEV能够发展为慢性戊型肝炎.有些慢性戊型肝炎病例肝脏快速纤维化而出现肝硬化,并最终导致肝脏衰竭.患者免疫抑制作用减弱,免疫功能恢复有助于体内持续存在的HEV清除.研究发现干扰素和利巴韦林对治疗慢性戊型肝炎有效.     

Chronic hepatitis E after solid organ transplantation

Large outbreaks of acute hepatitis E, caused by hepatitis E virus (HEV) genotypes 1 and 2, are known from developing countries with suboptimal sanitation infrastructure. An increasing incidence of HEV infections is being reported in industrialised countries, caused mainly by HEV genotypes 3 and 4, which are often found among pigs. Recent evidence suggests that in immunocompromised patients about 50% of the cases of acute hepatitis E evolve to chronic hepatitis with rapid progression to cirrhosis. Thus, HEV should be considered a cause of chronic hepatitis in immunocompromised patients, such as solid organ transplant recipients. Because an antibody response to HEV may be absent in these patients, an HEV RNA test should be carried out when serum liver tests are elevated over months. In small case series, ribavirin has been shown to represent a promising treatment option for chronic HEV infection. To increase the awareness for HEV infection in immunocompromised patients, a representative case report of an HEV-infected renal transplant recipient with chronic hepatitis E, successfully treated with ribavirin, is presented. Studies are required to determine the optimal duration of ribavirin therapy and to assess outcome for solid organ transplant recipients with chronic HEV infection.     

警惕输血引起的慢性戊型肝炎

戊型肝炎主要是HEV经粪-口传播引起的病毒性肝炎,然而近年来陆续报道了一些通过输血传播的病例。虽然通常情况下戊型肝炎为急性自限性疾病,但患者如处于免疫抑制状态（如器官移植、肿瘤化疗或HIV感染等）,感染HEV后会发展为慢性肝炎,并有可能迅速发展为肝纤维化和肝硬化。由于这些患者常常需要多次输血,更加大了感染HEV的风险。本文总结了全球献血员的HEV流行情况、经输血传播HEV的病例及免疫缺陷患者感染HEV后的危害等,提示应警惕输血引起的慢性戊型肝炎。     

Hepatitis E infection in HIV‐infected liver and kidney transplant candidates

Hepatitis E virus (HEV) has been reported to cause acute and chronic hepatitis in those with HIV infection and among solid organ transplant recipients in Europe. Limited data indicate that HEV is endemic in the United States, but the prevalence and significance of HEV infection among those with HIV and awaiting solid organ transplantation is unknown. We evaluated anti‐HEV IgM and IgG antibodies and HEV RNA in 166 HIV‐infected solid organ transplant candidates enrolled in the NIH HIV‐Transplant Cohort. Overall prevalence of anti‐HEV IgG approached 20% in both liver and renal transplant candidates. Evidence of recent infection was present in approximately 2% of liver transplant candidates and none of the kidney transplant candidates. HEV RNA was not detected in any patient. We conclude that markers of HEV infection are frequent among candidates for transplantation, but active, ongoing viremia is not seen. Evidence of recent infection (acute on chronic) liver disease was present in liver but not kidney recipients.     

Successful treatment of hepatitis E virus‐associated cryoglobulinemic membranoproliferative glomerulonephritis with ribavirin

Hepatitis E virus genotype‐3 (HEV3) infection can cause chronic hepatitis in immunosuppressed patients and induce extra‐hepatic manifestations, such as neurological symptoms, kidney injuries, and immune‐mediated thrombocytopenia. Very few cases of HEV‐induced kidney manifestations have been reported. Herein, we report, for the first time, a case of de novo membranoproliferative glomerulonephritis that occurred in a kidney transplant patient who developed a chronic HEV3 infection, which was successfully treated with ribavirin.     

Hepatitis E and pregnancy: understanding the pathogenesis

Hepatitis E virus (HEV) is a single‐stranded RNA virus that causes large‐scale epidemics of acute viral hepatitis, particularly in developing countries. In men and non‐pregnant women, the disease is usually self‐limited and has a case‐fatality rate of less than <0.1%. However, in pregnant women, particularly from certain geographical areas in India, HEV infection is more severe, often leading to fulminant hepatic failure and death in a significant proportion of patients. In contrast, reports from Egypt, Europe and the USA have shown that the course and severity of viral hepatitis during pregnancy is not different from that in non‐pregnant women. The reasons for this geographical difference are not clear. The high mortality rate in pregnancy has been thought to be secondary to the associated hormonal (oestrogen and progesterone) changes during pregnancy and consequent immunological changes. These immunological changes include downregulation of the p65 component of nuclear factor (NF‐κB) with a predominant T‐helper type 2 (Th2) bias in the T‐cell response along with host susceptibility factors, mediated by human leucocyte antigen expression. Thus far, researchers were unable to explain the high HEV morbidity in pregnancy, why it is different from other hepatitis viruses such as hepatitis A with similar epidemiological features and the reason behind the difference in HEV morbidity in pregnant women in different geographical regions. The recent developments in understanding the immune response to HEV have encouraged us to review the possible mechanisms for these differences. Further research in the immunology of HEV and pregnancy is required to conquer this disease in the near future.     

Hepatitis E,what’s the real issue?

Hepatitis E Virus (HEV) infection is a worldwide disease and the primary cause of acute viral hepatitis in the world with an estimated 20 million cases every year and 70 000 deaths. Hepatitis E is a waterborne infection in the developing countries. In these countries, HEV genotypes 1 and 2 cause large outbreaks and affect young subjects, resulting in significant mortality in pregnant women and patients with cirrhosis. In the developed countries, HEV genotypes 3 and 4 are responsible for autochthonous, sporadic hepatitis and transmission is zoonotic. Parenteral transmission by the transfusion of blood products has been identified as a potential new mode of transmission. The prevalence of positive HEV viraemia in blood donors in Europe ranges from 1/600 to 1/2500 in highly endemic European countries. HEV can cause neurological disorders and chronic infections in immunocompromised patients. The progression of acute hepatitis E is usually asymptomatic and resolves spontaneously. Diagnostic tools include anti‐HEV IgM antibodies in serum and/or viral RNA detection in the blood or the stools by PCR. Ribavirin is used to treat chronic infection. A vaccine has been developed in China.     

Hepatitis E: virología molecular,epidemiología y patogénesis

Hepatitis E represents a significant proportion of enteric transmitted liver diseases and poses a major public health problem, mainly associated with epidemics due to contamination of water supplies, especially in developing countries. Hepatitis E virus (HEV) is responsible for self-limiting acute liver oral-faecal infections. In industrialised countries, acute hepatitis E is sporadic, detected in travellers from endemic areas but also in sporadic cases with no risk factors. HEV is a non-enveloped virus with a single-stranded RNA genome classified into 4 genotypes and a single serotype. Genotypes 1 and 2 only infect humans, and are predominant in the developing countries, while 3 and 4 are predominant in industrialised countries, and also infect other species of mammals, especially pigs, and multiple evidence classifies HEV as a zoonotic agent. Some HEV chronic infections have recently been reported in kidney and liver transplant patients. The mortality rate of HEV infection is greater than hepatitis A. In addition to faecal-oral transmission, parenteral transmission of HEV has also been reported. Several vaccines are currently in development. The severity of this infection in some groups of patients, especially pregnant women, and the occurrence of chronic hepatitis, even with progression to cirrhosis, have raised interest in the application of interferon and/or ribavirin therapy.     

Epidemiology of hepatitis E: Current status

Hepatitis E, caused by infection with hepatitis E virus (HEV), is a common cause of acute hepatitis in areas with poor sanitation. The virus has four genotypes with one serotype: genotypes 1 and 2 exclusively infect humans, whereas genotypes 3 and 4 also infect other animals, particularly pigs. In endemic areas, both large outbreaks of acute hepatitis as well as sporadic cases occur frequently. These cases are usually due to genotype 1 or 2 HEV and are predominantly caused by fecal–oral transmission, usually through contamination of drinking water; contaminated food, materno-fetal (vertical spread) and parenteral routes are less common modes of infection. The acute hepatitis caused by this virus has the highest attack rates in young adults and the disease is particularly severe among pregnant women. HEV superinfection can occur among persons with pre-existing chronic liver disease. In non-endemic regions, locally acquired disease was believed to be extremely uncommon. However, in recent years, an increasing number of cases, due mostly due to genotype 3 or 4 HEV, have been recognized. These are more often elderly men who have other coexisting illnesses, and appear to be related to zoonotic transmission from pigs, wild boars and deer, either food-borne or otherwise. Also, chronic infection with genotype 3 HEV has been reported among immunosuppressed persons in these regions. A subunit vaccine has been shown to be effective in preventing clinical disease, but is not yet commercially available. Our understanding of hepatitis E epidemiology has undergone major changes in recent years, and the future may hold even more surprises.     

Hepatitis E virus:Epidemiology,diagnosis,clinical manifestations,and treatment

The hepatitis E virus(HEV) is the fifth known form of viral hepatitis and was first recognized as the cause of an epidemic of unexplained acute hepatitis in the early 1980 s. Globally, it is one of the most frequent causes of acute viral hepatitis. The majority of HEV infections are asymptomatic and lead to the spontaneous clearance of the virus. Among the eight different genotypes identified to date, HEV genotype 1(HEV1), HEV2, HEV3, and HEV4 are the most frequent genotypes causing infections in humans. HEV1 and HEV2 are prevalent in developing regions and able to result in large-scale outbreaks originating from contaminated water supplies. They are also responsible for severe hepatitis in pregnant patients and infants. In contrast, HEV3 and HEV4 are zoonotic, and the transmission of these genotypes to humans occurs mainly through the fecal contamination of water and consumption of contaminated meat from infected animals. Their main reservoir is the pig, and they are mostly encountered in developed countries. The major risk groups for HEV infection and its ensuing adverse consequences are pregnant women, infants, older people, immunocompromised individuals, patients with underlying chronic liver diseases, and workers that come into close contact with HEV-infected animals. In the clinical perspective, HEV infections have diverse clinical manifestations including acute and self-limiting hepatitis, acute-on-chronic liver disease, chronic hepatitis, cirrhosis, and liver failure. Although HEV mainly results in acute selflimiting infection, chronic HEV infection may occur among immunocompromised patients(e.g., solid-organ transplant recipients). Additionally, HEV-associated extrahepatic manifestations involving various organs have been reported in the last decade, although the causal link for many of them still needs to be proven. Ribavirin and interferon-alpha are the most widely used agents for the treatment of HEV infections with a certain level of success. However, ribavirin is contraindicated in pregnant patients, and interferon-alpha cannot be used in most transplant recipients. Therefore, there is an urgent need for novel antiviral compounds that are safe and effective particularly for patients having contraindications for ribavirin or interferon-alpha and infected by the ribavirinresistant HEV. In this review article, a literature search using PubMed and MEDLINE databases was performed, up to March 2020. Only the articles published in English were reviewed.     

Features of hepatitis E virus infection in humans and animals in Japan

In Japan, hepatitis E had long been considered to be a rare liver disease which can be accidentally imported from endemic countries in Asia and Africa, where the sanitation conditions are suboptimal. However, since the identification of the first autochthonous hepatitis E case and hepatitis E viremic domestic pigs in Japan in 2001, our understanding of hepatitis E virus (HEV) infection in this country has been changing markedly. This has largely been due to the development of serological and gene‐based diagnostic assays, the accumulation of molecular epidemiological findings on HEV infection in humans and animals (as potential reservoirs for HEV in humans) and the recognition of the importance of zoonotic food‐borne and other routes of transmission of HEV, including blood‐borne transmission. Although it is now evident that autochthonous hepatitis E in Japan is far more common than was previously thought, clinical and subclinical HEV infections indigenous to Japan remain underdiagnosed and their prevalence is still underestimated due to the presence of unknown transmission routes and a low awareness of the infection status by many physicians in Japan. This review focuses on the features of HEV infection in humans and animals, as definitive or potential reservoirs for HEV, in Japan, and updates the current knowledge on the routes of transmission, including zoonotic routes, which are important for the maintenance and spread of HEV in Japan.     

Chronic hepatitis E in hematopoietic stem cell transplant patients in a low‐endemic country?

Cases of chronic hepatitis E have been described in patients after kidney and liver transplantation. In addition, hepatitis E virus (HEV) reactivation was reported after hematopoietic stem cell transplantation (HSCT). We here evaluated if HEV infection might explain elevated liver enzymes in a well selected cohort of allogeneic HSCT patients with biochemical evidence of hepatitis (n = 52). Of note, none of the subjects tested positive for HEV RNA, including 2 HSCT patients who had been infected with HEV already before transplantation. Thus, both chronic courses of HEV infections and HEV reactivations seem to be rather rare events in HSCT patients in a non-endemic country.     

Hepatitis E: An Underdiagnosed,Emerging Infection in Nonendemic Regions

Although hepatitis E virus (HEV) is the primary cause of enterically transmitted acute hepatitis and jaundice in developing countries, locally acquired HEV infections are increasing in nonendemic countries. As such, HEV is emerging as an underdiagnosed cause of infection. This report describes three clinically variable cases of HEV infection with unusual clinical presentations. These cases highlight the fact that HEV should be considered in the differential diagnosis of patients with unexplained hepatitis (acute or chronic) with or without extrahepatic manifestations. HEV should also be considered in patients with persistently elevated liver enzymes who have not travelled to known HEV-endemic regions. Lack of knowledge among physicians and an absence of standardized diagnostic tests may result in increased morbidity and mortality from HEV infection.