Rituximab Therapy for Insulin Allergy in Type-1 Diabetes Mellitus

Allergic reactions to insulin have decreased significantly since the introduction of human insulin preparation, but up to 2.4% of insulin-treated patients can still be affected. Rituximab is a monoclonal antibody against the surface antigen CD20 on B lymphocytes, and it is largely used to treat lymphoproliferative and rheumatological conditions. In a very few published case reports, rituximab has been used as an investigational drug to treat severe insulin allergy refractory to conventional therapy. Here, we present an unusual case of a 40-year-old woman with T1DM and severe insulin allergy that was successfully treated with rituximab.