Alemtuzumab induced red cell aplasia and other immune cytopenias - not so 'pure'

Lay abstract We report a case of 28-year-old women with relapsing remitting multiple sclerosis who was treated with alemtuzumab and subsequently developed a series of autoimmune complications. Several months after completing her second course of alemtuzumab the patient became breathless and noticed bruising on her legs. On investigation she was found to be anemic and had a low platelet level (which predisposed her to bruising). In addition, her immune system was also impaired meaning she was more prone to developing opportunistic infections. The patient was treated with a variety of different medications and required blood transfusions for several months before she recovered. Despite the multiple complications the patient developed from alemtuzumab her multiple sclerosis remains stable with no new relapses 3 years following treatment. We report on the presentation and outcome of a 28-year-old female who developed red cell aplasia following alemtuzumab therapy for relapsing remitting multiple sclerosis. The patient also developed synchronous immune thrombocytopenia and immune neutropenia, but not aplastic anemia. This patient received high dose steroids, intravenous immunoglobulin (iv.Ig), rituximab, red cell transfusions, vincristine, G-CSF, cyclosporin and mycophenolate to treat the combination of cytopenias over a period of 6 months with subsequent improvement in bone marrow function. While alemtuzumab has several recognized autoimmune complications, little is known about the potential hematological side effects. The combination of red cell aplasia, immune thrombocytic purpura and autoimmune neutropenia has not previously been described in the literature following alemtuzumab immunotherapy and highlights the importance of monthly blood monitoring post alemtuzumab administration.