Hepatitis E virus infection: considerations for immunologists and rheumatologists.

Globally widespread hepatitis E virus (HEV) is considered an emerging epidemiological threat, particularly dangerous for those with compromised immunity, including transplant recipients and patients with rheumatic diseases. The management of this infection involves many challenges, particularly in patients with rheumatic diseases. The aim of this review has been to provide a comprehensive, summary of the current knowledge, focusing on applicable for rheumatology practice. The review was conducted using Scopus, PubMed, and Web of Science databases. Searched terms included hepatitis E virus, HEV, rheumatology, connective tissue disease. Multiple studies suggest the underassessment of the prevalence. There are four main genotypes, HEV3 is typical for Europe, and its transmission is associated with undercooked wild boar or pork meat consumption. The disease is usually self-limiting, presenting as an acute hepatitis; chronic infections also occur, especially in immunosuppressed. Multiple extrahepatic manifestations, most often neurological, have been described. This variety of symptoms is attributed to the impact on the immune system. Diagnosis of the infection is often challenging. Treatment is not required in acute infections. Immunocompromised may need a reduction of immunosuppressants. Ribavirin off-label use is also recommended by the experts. HEV infection poses an important risk to immunosuppressed patients. Further research is required to fully reveal the mechanisms of infection and proper strategies of treatment. It is important for clinicians taking care of immunocompromised to include HEV in the differential diagnosis, even when typical signs and symptoms are not present.