Viral encephalitis associated with rituximab maintenance therapy: two cases and a review of literature.

Rituximab is increasingly used in the treatment of CD20-positive B-cell-mediated disease. Prolonged use may cause B-cell dysfunction, dose-dependent T-cell dysfunction, and hypogammaglobulinaemia and result in severe non-neutropenic infections. We present two cases of viral encephalitis in patients treated with rituximab maintenance therapy: one patient presented with deafness; the other patient with paroxysmal light flashes, apraxia, and weakness.