Hepatitis E virus (HEV) is considered an agent responsible for acute hepatitis that does not progress to chronic hepatitis. We identified 14 cases of acute HEV infection in three patients receiving liver transplants, nine receiving kidney transplants, and two receiving kidney and pancreas transplants. All patients were positive for serum HEV RNA. Chronic hepatitis developed in eight patients, as confirmed by persistently elevated aminotransferase levels, serum HEV RNA, and histologic features of chronic hepatitis. The time from transplantation to diagnosis was significantly shorter and the total counts of lymphocytes and of CD2, CD3, and CD4 T cells were significantly lower in patients in whom chronic disease developed.

A weak immune response to two doses of vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been observed in recipients of solid-organ transplants.^1,2 Severe cases of coronavirus disease 2019 (Covid-19) have also been reported in transplant recipients who had received two doses of vaccine.³ These reports prompted the French National Authority for Health to recommend the use of a third dose in immunosuppressed patients.⁴ Here, we report the humoral response in a group of 101 consecutive solid-organ transplant recipients (mean [±SD] age, 58±2 years; 69% were men) who were given three doses of the messenger RNA vaccine BNT162b2 (Pfizer–BioNTech). The group included 78 kidney-transplant recipients, 12 liver-transplant recipients, 8 lung-transplant or heart-transplant recipients, and 3 pancreas-transplant recipients. The first two doses were given 1 month apart, and the third dose was administered 61±1 days after the second dose. The time between transplantation and the initiation of vaccination was 97±8 months. Immunosuppression was due to the use of glucocorticoids (in 87% of patients), calcineurin inhibitors (in 79% of patients), mycophenolic acid (in 63% of patients), mammalian target of rapamycin inhibitors (in 30% of patients), and belatacept (in 12% of patients). The levels of antibodies to SARS-CoV-2 spike protein were assessed in all the patients with the use of the Wantai enzyme-linked immunosorbent assay (Beijing Wantai Biological Pharmacy Enterprise).⁵ Antibody titers are expressed as the ratio of the sample signal to a calibrator-assigned cutoff signal (the signal-to-cutoff ratio). According to French law, because this was an anonymous retrospective study, institutional review board approval was not required.

SUMMARY: Hepatitis E virus (HEV) infection is a worldwide disease. An improved understanding of the natural history of HEV infection has been achieved within the last decade. Several reservoirs and transmission modes have been identified. Hepatitis E is an underdiagnosed disease, in part due to the use of serological assays with low sensitivity. However, diagnostic tools, including nucleic acid-based tests, have been improved. The epidemiology and clinical features of hepatitis E differ between developing and developed countries. HEV infection is usually an acute self-limiting disease, but in developed countries it causes chronic infection with rapidly progressive cirrhosis in organ transplant recipients, patients with hematological malignancy requiring chemotherapy, and individuals with HIV. HEV also causes extrahepatic manifestations, including a number of neurological syndromes and renal injury. Acute infection usually requires no treatment, but chronic infection should be treated by reducing immunosuppression in transplant patients and/or the use of antiviral therapy. In this comprehensive review, we summarize the current knowledge about the virus itself, as well as the epidemiology, diagnostics, natural history, and management of HEV infection in developing and developed countries.