Late hepatitis B virus reactivation after lamivudine prophylaxis interruption in an anti-HBs-positive and anti-HBc-negative patient treated with rituximab-containing therapy.

We describe a case of an anti-HBs-positive patient who experienced hepatitis B reactivation 18 months after the discontinuation of rituximab and after 12 months of lamivudine prophylaxis. The patient carried a hepatitis B genotype D virus harbouring a single immune escape mutation, sT118K. No consensus guidelines regarding the optimal length of treatment or the best elective drug have been defined for antiviral prophylaxis for HBsAg-negative, anti-HBc- and/or anti-HBs-positive patients undergoing immunosuppressive treatment. Screening based on HBV serological markers and HBV DNA testing is a critical issue to recognise hepatitis B reactivation as early as possible. Furthermore, it is of outstanding importance to identify alternative markers (e.g. cccDNA, HBV core related antigen, etc.), that could be predictive of HBV reactivation.