Hepatitis B virus reactivation in a primary central nervous system lymphoma patient following intrathecal rituximab treatment.

A 69-year-old woman with relapsed primary central nervous system (CNS) lymphoma was treated with intrathecal rituximab without a concomitant systemic steroid or other chemotherapeutic drugs. Her initial viral status was HBs Ag negative and anti-HBs Ab positive. After 12 weeks of the last intrathecal rituximab application, the levels of AST and ALT were 1,005 and 1,134 IU/l, respectively. The viral status was changed as follows: HBs Ag positive, anti-HBs Ab negative, anti-HBe Ag positive, and anti-HBe Ab negative. The titer of hepatitis B virus (HBV) DNA was 106,000 IU/ml. She was diagnosed with acute hepatitis due to HBV reactivation. To our knowledge, this is the first reported case of HBV reactivation occurring after intrathecal rituximab monotherapy, suggesting that monitoring of HBV markers should be considered during intrathecal rituximab treatment in primary CNS lymphoma patients who are HBs Ag positive or anti-HBs Ab positive.