Rituximab-Associated Liver Toxicity Without Known Viral Reactivation.

Rituximab is a targeted immunotherapeutic agent that has demonstrated efficacy in treating CD20+ B-cell neoplasms as well as other lymphoproliferative and autoimmune disorders. A major adverse effect of rituximab is hepatocellular injury attributed to hepatitis B viral reactivation, necessitating viral titers before treatment. In this case report, we illustrate the rare presentation of a patient with marginal zone B-cell lymphoma who experienced symptomatic liver injury with a peak 15-fold aminotransferase elevation following his first dose of rituximab, without evidence of viral reactivation.