Horizontal transmission of de novo hepatitis B between spouses: A case report.

We report a female patient with acute hepatitis B due to horizontal transmission of hepatitis B virus from her husband, who suffered from de novo hepatitis B. A 48-year-old man underwent peripheral blood stem cell transplantation (PBSCT) for adult T-cell leukemia/lymphoma. Nine months after the initial treatment, he was referred to our hospital because of jaundice. Laboratory data showed elevated serum aminotransferase levels and hepatitis B surface antigen (HBsAg) positivity. We diagnosed de novo hepatitis B because a pre-PBSCT serum sample was negative for HBsAg and positive for anti-hepatitis B core antibody (HBcAb). His liver function improved with entecavir therapy. Two months after his diagnosis of hepatitis B, his 31-year-old wife was admitted with fever and appetite loss. She was diagnosed with acute hepatitis B because of increased serum aminotransferase levels and HBsAg and immunoglobulin M HBcAb positivity. Sequencing of HBV DNA in the serum obtained from both patients showed 99.9% homology. Therefore, we diagnosed her acute hepatitis B as due to horizontal transmission of de novo hepatitis B from her husband. HBV derived from de novo hepatitis B should be considered a potential source of infection, although intrafamilial transmission of de novo hepatitis B is rare.