Rituximab Induced Neutropenia in a Patient with Bullous Pemphigoid

Rituximab, a chimeric monoclonal antibody against the CD20 B-cell antigen, is used to treat B-cell malignancies, rheumatoid arthritis, and autoimmune blistering diseases. Adverse events seen with rituximab include infusion reactions, infections, and late or early-onset neutropenia. Specifically, neutropenia is classified as grade III, an absolute neutrophil count (ANC) of 0.5-1.5 x 109/L, or grade IV, an ANC less than 0.5 x 109/L. In this case, we present a bullous pemphigoid (BP) patient with grade IV rituximabinduced neutropenia and safe re-treatment after two years.