Time course alterations of virus sequences and immunoglobulin titers in a chronic hepatitis E patient.

Abstract

HepatitisE virus (HEV) can cause chronic infection in immunocompromised hosts. However, the dynamics of HEV during persistent infection is not well understood. To elucidate time course alterations in virus sequences and anti-HEV antibodies during persistent infection, we analyzed the HEV sequences and titers of anti-HEV antibodies from a chronic hepatitisE patient. Serum samples were obtained from a chronic hepatitisE patient under corticosteroid therapy for neurological disease. The titers of anti-HEV antibodies (immunoglobulinA, immunoglobulinM, and immunoglobulinG) in serum samples were detected by enzyme immunoassay. The full or near-full nucleotide sequences of HEV isolated from consecutive serum samples were identified and compared. Phylogenetic analysis was also performed. Alterations of anti-HEV antibodies from a chronic hepatitisE patient were different from those previously reported in acute hepatitisE patients. The virus sequence was unchanged in the period without treatment, but nucleotide mutations were observed after ribavirin treatment was started. In addition, the sequence of this strain had extremely high identity to that isolated from swine liver in Japan. Virus mutations in HEV emerged after ribavirin treatment was started. Sequence analysis may useful for deciding the treatment strategy for chronic hepatitisE patients who did not eliminate the virus with 3months of RBV treatment and inferring the origin of the infection. This report provides insights into the chronicity of hepatitisE, and the impact of persistent infection and ribavirin treatment on the emergence of virus mutations.