Hepatitis E infection in stem cell and solid organ transplantpatients: A cross-sectional study: The importance of HEV RNA screening in peri-transplant period

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.

Hepatitis E Virus Infection Epidemiology in Recipients of Allogeneic Hematopoietic Cell Transplant

Among 292 recipients of allogeneic hematopoietic cell transplant (2018-2022), 64 (21.9%) tested positive for anti-hepatitis E virus (HEV) immunoglobulin G. Among 208 recipients tested by plasma/serum HEV polymerase chain reaction (2012-2022), 3 (1.4%) primary HEV infections were diagnosed; in 1 patient, plasma HEV polymerase chain reaction relapsed positive for 100 days. HEV infection remains rare albeit associated with persistent viral replication.

Hepatitis E Virus Infection, a Risk for Liver Transplant Recipients in Sweden

Following exposure to hepatitis E virus (HEV), liver transplant (LT) recipients have an increased risk of developing chronic infection, which may rapidly progress to severe liver damage if not treated. The prevalence of HEV infection after LT is unclear and likely varies geographically. The aim of this study was to investigate the prevalence of acute and chronic HEV infection among LT recipients in an HEV endemic region.

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.

[Vaccines against hepatitis E virus: state of development]

In Europa ist aktuell kein Impfstoff gegen das Hepatitis-E-Virus (HEV) zugelassen. Demgegenüber steht in China bereits seit 10 Jahren mit HEV-239 (Hecolin®, Xiamen Innovax Biotech Co., Xiamen, China) ein Vakzin gegen den HEV-Genotyp 4 zur Verfügung. Herausforderungen für die Entwicklung von Impfstoffen ergeben sich v. a. aus den Unterschieden zwischen den Genotypen bezüglich Verbreitung, Übertragungswege und Risikogruppen. Weitere Hindernisse sind die Umhüllung von HEV im Blut durch Wirtsmembranen, die Replikation in verschiedenen Organen außerhalb der Leber sowie schwächere Immunantworten in vulnerablen Gruppen. In diesem Artikel wird der aktuelle Stand der verfügbaren und in fortgeschrittener präklinischer Evaluation befindlichen Vakzine gegen HEV mit Fokus auf Strategien der Impfstoffentwicklung dargestellt. Herausforderungen und Limitationen werden beschrieben.

Aktuelle Impfkandidaten fokussieren auf proteinbasierte Immunisierungen mit dem Ziel der Induktion von schützenden, neutralisierenden Antikörperantworten. Das Ziel der HEV-239-Zulassungsstudie mit mehr als 100.000 Studienteilnehmern war die Verhinderung von akuten symptomatischen Infektionen. Es ist jedoch unklar, inwieweit asymptomatische Infektionen durch das Vakzin verhindert wurden und ob es in Risikopatienten für einen komplizierten Verlauf, wie Patienten mit Leberzirrhose, Immunsupprimierten und Schwangeren, effektiv genug wirkt. Effiziente In-vitro-Modelle ermöglichen zunehmend die Entwicklung von monoklonalen neutralisierenden Antikörpern zur passiven Immunisierung oder Therapie.

Zukünftige Vakzine sollten neben einem sehr guten Sicherheitsprofil eine eindeutige Protektion gegenüber allen Genotypen demonstrieren. Die Entwicklung einer effizienten passiven Immunisierungsstrategie, insbesondere für immunsupprimierte Personen, ist wünschenswert.

Hepatitis E virus infection in hematopoietic stem cell transplant recipients: a systematic review and meta-analysis

Although most patients with hepatitis E virus (HEV) infection are asymptomatic or have mild symptoms, its infection is generally underdiagnosed and overlooked. In immunocompromised patients, HEV infection can lead to acute liver failure and death. However, the clinical evidence of HEV infection in hematopoietic stem cell transplant (HSCT) recipients is scarce; thus, we conducted this systematic review and meta-analysis to assess the prevalence of HEV infection in this population. We searched MEDLINE, EMBASE, and the Cochrane Library databases from inception through October 2020 to identify studies that reported the prevalence of HEV infection among HSCT recipients. HEV infections were confirmed by HEV-IgG/IgM or HEV-RNA assay. A total of 1977 patients from nine studies with a follow-up time up to 40 months were included in the final analysis. The pooled prevalence of positive HEV-RNA was 3.0% (95% CI 2.3% to 4.0%). The pooled prevalence of positive HEV-IgG was 10.3% (95% CI 4.5% to 21.8%). The pooled prevalence of de novo HEV infection was 2.9% (95% CI 1.8% to 4.5%). Age and male gender were not associated with HEV-RNA or HEV-IgG positivity in the meta-regression analysis. In conclusion, the prevalence of HEV-IgG in HSCT recipients was about 10%, while the prevalence of HEV-RNA was only 3%. However, further studies that focus on the clinical outcomes in this population are warranted.

HEV infection in stem cell transplant recipients-retrospective study of EBMT Infectious Diseases Working Party

HEV infection is an emerging cause of acute and chronic hepatitis in stem cell transplant (SCT) recipients. We performed a retrospective observational study among EBMT centers with the aim of describing characteristics, management and outcome of HEV after SCT. There were 34 cases of HEV infection from 12 centers in 6 countries, diagnosed in median 4.5 months after SCT; 20 of acute and 14 of chronic infection. Non-hepatic findings possibly associated with HEV infection were present in 9 (26%). Patients with chronic infection had more characteristics associated with severely immunocompromised status. Ribavirin was provided to 16 patients (47%; 40% with acute and 57% with chronic infection), in median for 75 days. Three (19%) patients discontinued it due to side effects. HEV-RNA clearance occurred in 29 patients (85%; 85% in acute and 86% in chronic infection). HEV was considered a cause of death in 3 (9%), with 2 cases with late diagnosis. Reduction of immunosuppression in those receiving it, and ribavirin treatment in those with chronic infection were associated with shorter time to HEV-RNA clearance. Policy on HEV testing varied between the centers. In conclusion, acute and chronic HEV hepatitis should be promptly diagnosed and managed in SCT recipients.

Evaluation of a Novel CLIA Monotest Assay for the Detection of Anti-Hepatitis E Virus-IgG and IgM: A Retrospective Comparison with a Line Blot and an ELISA

Despite the increasing relevance of Hepatitis E, an emerging disease endemic in developing and with increasing numbers of sporadic cases in industrialized countries, commercial tests are mainly based on batch oriented serological assays. In this retrospective study, we compared a line immunoassay (LIA; recomLine HEV, Mikrogen) and an ELISA (EIA; Anti-Hepatitis E Virus ELISA, Euroimmun) with a novel chemoluminescence immunoassay in a monotest format (CLIA; Hepatitis E VirClia, Vircell). Twenty sera of PCR proven cases of hepatitis E and 68 blood samples serologically pre-characterized were included. Applying the WHO reference standard, the CLIA demonstrated the highest analytical sensitivity for IgG and IgM. The combinations of CLIA/EIA (IgG and IgM) and CLIA/LIA (IgG) measurements showed substantial correlation. Compared to overall antibody detection (seropositivity in ≥2 assays), CLIA correlation was excellent, outperforming LIA (IgM) and EIA (IgG and IgM). Minor IgM cross reactivity in samples of patients with acute EBV infection was observed in all three assays. The CLIA showed good performance in diagnostic samples compared to established LIA and EIA assays. Due to its ready-to-use monotest format, the CLIA allows simple, time- and cost-effective handling of single samples. These qualities make the assay suitable for diagnostics, especially in the emergency setting and for low-throughput laboratories.

Hepatitis E in solid organ transplant recipients: A systematic review and meta-analysis

BACKGROUND

Hepatitis E virus (HEV) infection is underdiagnosed due to the use of serological assays with low sensitivity. Although most patients with HEV recover completely, HEV infection among patients with pre-existing chronic liver disease and organ-transplant recipients on immunosuppressive therapy can result in decompensated liver disease and death.

AIM

To demonstrate the prevalence of HEV infection in solid organ transplant (SOT) recipients.

METHODS

We searched Ovid MEDLINE, EMBASE, and the Cochrane Library for eligible articles through October 2020. The inclusion criteria consisted of adult patients with history of SOT. HEV infection is confirmed by either HEV-immunoglobulin G, HEV-immunoglobulin M, or HEV RNA assay.

RESULTS

Of 563 citations, a total of 22 studies (n = 4557) were included in this meta-analysis. The pooled estimated prevalence of HEV infection in SOT patients was 20.2% [95% confidence interval (CI): 14.9-26.8]. The pooled estimated prevalence of HEV infection for each organ transplant was as follows: liver (27.2%; 95%CI: 20.0-35.8), kidney (12.8%; 95%CI: 9.3-17.3), heart (12.8%; 95%CI: 9.3-17.3), and lung (5.6%; 95%CI: 1.6-17.9). Comparison across organ transplants demonstrated statistical significance (Q = 16.721, P = 0.002). The subgroup analyses showed that the prevalence of HEV infection among SOT recipients was significantly higher in middle-income countries compared to high-income countries. The pooled estimated prevalence of de novo HEV infection was 5.1% (95%CI: 2.6-9.6) and the pooled estimated prevalence of acute HEV infection was 4.3% (95%CI: 1.9-9.4).

CONCLUSION

HEV infection is common in SOT recipients, particularly in middle-income countries. The prevalence of HEV infection in lung transplant recipients is considerably less common than other organ transplants. More studies examining the clinical impacts of HEV infection in SOT recipients, such as graft failure, rejection, and mortality are warranted.

Treatment for chronic hepatitis E virus infection: A systematic review and meta-analysis

Hepatitis E virus infection can cause chronic hepatitis in immunocompromised patients with significant chance of progressive fibrosis and possibly cirrhosis. The aim of this systematic review was to summarize the efficacy and safety of the various treatment options for chronic hepatitis E. We performed a systematic literature search. The primary outcome measure was a sustained virological response (SVR). Secondary end points were rapid virological response (RVR), relapse rates, side effects and adverse events. Forty-four articles were included with a total of 582 patients. Reduction of immunosuppressive medication induced viral clearance in 55/174 (32%) of the patients. Meta-analysis of 395 patients showed a pooled SVR rate of 78% (95-CI 72%-84%) after ribavirin treatment. Twenty-five per cent of the patients obtained a RVR, whereas a relapse occurred in 18% of the patients. Anaemia during treatment led to dose reduction, use of erythropoietin and/or blood transfusion in 37% of the patients. A second treatment attempt with ribavirin led to a SVR in 39/51 (76%) of the patients. Pegylated interferon-alpha was administered to 13 patients and SVR was obtained in 85%. Two patients (15%) suffered from acute transplant rejection during treatment with interferon. In conclusion, reduction of immunosuppressive medication and treatment with ribavirin is safe, generally well tolerated and induced viral clearance in 32% and 78% of patients, respectively. Therefore, ribavirin should be considered as first treatment step for chronic hepatitis E. Treatment with pegylated interferon-alpha increases the risk of transplant rejection and should therefore be administered with great caution.

Persistent Hepatitis E virus infection across England and Wales 2009-2017: Demography, virology and outcomes

The first clinical case of persistent HEV infection in England was reported in 2009. We describe the demography, virology and outcomes of patients identified with persistent HEV infection in England and Wales between 2009 and 2017. A series of 94 patients with persistent HEV infection, defined by HEV viraemia of more than 12 weeks, was identified through routine reference laboratory testing. Virology, serology and clinical data were recorded through an approved PHE Enhanced Surveillance System. Sixty-six cases (70.2%) were transplant recipients, 16 (17.0%) had an underlying haematological malignancy without stem cell transplantation, six (6.4%) had advanced HIV infection, five (5.3%) were otherwise immunosuppressed, and one patient (1.1%) had no identified immunosuppression. Retrospective analysis of 46 patients demonstrated a median 38 weeks of viraemia before diagnostic HEV testing. At initial diagnosis, 16 patients (17.0%) had no detectable anti-HEV serological response. Of 65 patients treated with ribavirin monotherapy, 11 (16.9%) suffered virological relapse despite undetectable RNA in plasma or stool at treatment cessation. Persistent HEV infection remains a rare diagnosis, but we demonstrate that a broad range of immunocompromised patients are susceptible. Both lack of awareness and the pauci-symptomatic nature of persistent HEV infection likely contribute to significant delays in diagnosis. Diagnosis should rely on molecular testing since anti-HEV serology is insufficient to exclude persistent HEV infection. Finally, despite treatment with ribavirin, relapses occur even after cessation of detectable faecal shedding of HEV RNA, further emphasising the requirement to demonstrate sustained virological responses to treatment.

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.

Hepatitis E Virus Infection in an Italian Cohort of Hematopoietic Stem Cell Transplantation Recipients: Seroprevalence and Infection

Chronic hepatitis E virus (HEV) infection in hematopoietic stem cell transplantation (HSCT) recipients is an emerging threat. The aim of this study was to provide data on the HEV burden in an Italian cohort of HSCT recipients and analyze risk factors for HEV seropositivity. This retrospective study reports data from 596 HSCT recipients compiled between 2010 and 2019. It included patients who underwent transplantation between 2010 and 2015 for whom pretransplantation (n = 419) and post-transplantation (n = 161) serum samples were available and tested retrospectively, as well as patients in whom prospective HEV testing was performed during the standard care: pre-HSCT IgG screening in 144, pre-HSCT HEV-RNA screening in addition to IgG screening in 60, and HEV-RNA testing in case of clinical suspicion of HEV infection in 59 (26 of whom were also included in the IgG screening cohorts). The rate of pre-HSCT HEV-IgG positivity was 6.0% (34 of 563). Older age was an independent risk factor for seropositivity (P = .039). None of the 34 HEV-IgG-positive patients had detectable HEV-RNA. One case of transient HEV-RNA positivity pre-HSCT was identified through screening. Two patients were diagnosed with chronic HEV hepatitis, and 1 patient was successfully treated with ribavirin. The burden of HEV infection in HSCT recipients in Italy is limited, and pre-HSCT screening appears to be of no benefit. Timely diagnosis of HEV infection with HEV-RNA is mandatory in cases of clinical suspicion.

Cost-Effectiveness Analysis of Screening for Persistent Hepatitis E Virus Infection in Solid Organ Transplant Patients in the United Kingdom: A Model-Based Economic Evaluation

BACKGROUND

Despite potentially severe and fatal outcomes, recent studies of solid organ transplant (SOT) recipients in Europe suggest that hepatitis E virus (HEV) infection is underdiagnosed, with a prevalence of active infection of up to 4.4%.

OBJECTIVES

To determine the cost-effectiveness of introducing routine screening for HEV infection in SOT recipients in the UK.

METHODS

A Markov cohort model was developed to evaluate the cost-utility of 4 HEV screening options over the lifetime of 1000 SOT recipients. The current baseline of nonsystematic testing was compared with annual screening of all patients by polymerase chain reaction (PCR; strategy A) or HEV-antigen (HEV-Ag) detection (strategy B) and selective screening of patients who have a raised alanine aminotransferase (ALT) value by PCR (strategy C) or HEV-Ag (strategy D). The primary outcome was the incremental cost per quality-adjusted life-year (QALY). We adopted the National Health Service (NHS) perspective and discounted future costs and benefits at 3.5%.

RESULTS

At a willingness-to-pay of £20 000/QALY gained, systematic screening of SOT patients by any method (strategy A-D) had a high probability (77.9%) of being cost-effective. Among screening strategies, strategy D is optimal and expected to be cost-saving to the NHS; if only PCR testing strategies are considered, then strategy C becomes cost-effective (£660/QALY). These findings were robust against a wide range of sensitivity and scenario analyses.

CONCLUSIONS

Our model showed that routine screening for HEV in SOT patients is very likely to be cost-effective in the UK, particularly in patients presenting with an abnormal alanine aminotransferase.

Hepatitis E virus is an infrequent but potentially serious infection in allogeneic hematopoietic stem cell transplant recipients

Hepatitis E virus (HEV) can cause chronic infection and liver cirrhosis in immunocompromised individuals. The frequency and clinical importance of HEV was studied retrospectively in a cohort of 236 Swedish allogeneic hematopoietic stem cell transplantation (HSCT) recipients. In blood samples collected at 6 months after HSCT, HEV RNA was identified in 8/236 (3.4%) patients, and 11/236 (4.7%) patients had detectable anti-HEV IgG and/or IgM, eight of whom were HEV RNA negative. Two of the patients with positive HEV RNA died with ongoing signs of hepatitis: one of acute liver and multiple organ failure, the other of unrelated causes. The remaining six patients with HEV RNA had cleared the infection at 7-24 (median 8.5) months after HSCT. HEV infection was associated with elevated alanine aminotransferase at 6 months after HSCT (OR 15, 1.3-174, p = 0.03). Active graft-versus-host disease of the liver at 6 months after HSCT was present in 3/8 (38%) patients with HEV RNA, but was not significantly associated with HEV infection. In conclusion, HEV infection is an important differential diagnosis in patients with elevated liver enzymes after HSCT. Although spontaneous clearance was common, the clinical course may be severe.

Epidemiology of hepatitis E virus infection in a cohort of 4023 immunocompromised patients

OBJECTIVES

The prevalence of active, chronic, and former hepatitis E virus (HEV) infections was investigated in a cohort of immunocompromised patients. The association with transfusion transmitted HEV was evaluated, and the HEV seroprevalence was compared with that in healthy blood donors.

STUDY DESIGN AND METHODS

Serum samples from 4023 immunocompromised patients at Rigshospitalet, Denmark were retrospectively tested for HEV RNA and anti-HEV IgG. HEV RNA-positive patients were followed up by HEV testing, clinical symptoms, and transfusion history. Factors associated with anti-HEV were explored by multivariable logistic regression analysis. Samples from 1226 blood donors were retrospectively tested for anti-HEV IgG.

RESULTS

HEV RNA was detected in six patients (0.15%) with no indications of chronic HEV infection. HEV RNA prevalence rates among recipients of allogeneic haematopoietic stem cell transplantation (allo-HSCT) and solid organ transplantation (SOT) were 0.58% and 0.21%, respectively. Transfusion transmitted infections were refuted, and transfusion history was not associated with anti-HEV positivity. The difference in HEV seroprevalence between patients (22.0%) and blood donors (10.9%) decreased when adjusting for age and sex (odds ratio 1.20, 95% confidence interval 0.97-1.48).

CONCLUSIONS

HEV viremia among allo-HSCT and SOT recipients suggests that clinicians should be aware of this diagnosis. The lack of association of blood transfusion with anti-HEV positivity supports food-borne transmission as the main transmission route of HEV common to both patients and blood donors.