Results of Treatment with Rituximab (Anti-CD20) in Three Patients with Autoimmune Hemolytic Anemia and/or Immune Thrombocytopenia and a Concise Review of Reported Cases

Rituximab, a human-mouse chimeric monoclonal antibody against the CD20 antigen on B lymphocytes, is increasingly used for treatment of autoimmune diseases. We report on the outcome of rituximab therapy in 1 patient with decompensated idiopathic autoimmune hemolytic anemia (AIHA) and in 2 patients with severe immune thrombocytopenia (ITP) in combination with compensated AIHA (Evans’ syndrome). All 3 patients were refractory to conventional therapies and received rituximab in standard doses. While the drug led to a partial response in the patient with AIHA for roughly 8 months, it was largely ineffective in the 2 patients with Evans’ syndrome. Our results and those of all hitherto reported cases indicate that rituximab therapy is most effective in children with AIHA. It is also effective in 83% of adult patients with cold agglutinin disease (CAD), secondary AIHA and/or ITP, but in only 46% of adults with idiopathic AIHA and/or ITP.