Chronic hepatitis E in immunosuppressed patients: a comprehensive review of the literature

Hepatitis E virus (HEV) is the commonest cause of acute viral hepatitis in Western countries, especially genotypes 3 and 4. Chronic cases are reported in immunosuppressed patients, which includes patients who have undergone solid organ or stem cell transplantation, patients who are being treated for cancer or autoimmune diseases. Chronic HEV can eventually lead to liver fibrosis, and exceptional cases requiring liver transplantation for decompensated liver cirrhosis have been reported. The mechanisms leading to chronic HEV and its incidence in the immunosuppressed population is still unclear due to the paucity of well-designed prospective studies. According to studies conducted in various European countries, the HEV seroprevalence in immunocompromised patients ranges up to 40% and HEV RNA viremic prevalence between 0,5 to 2%. In this review, we provide a description of the epidemiology, risk factors and natural history of chronic HEV in relation to various types of underlying immunosuppressive conditions and discuss the different treatment options available.