Rituximab in the Treatment of Secondary Autoimmune Neutropenia.

Autoimmune cyclical neutropenia is a rare syndrome with periodically severe but temporary neutropenia with occurrence of 3–4 weeks, but not rarely in 2 or 5 week intervals. Antibodies with specificity for the neutrophils has been demonstrated in a number of different neutropenic disorders and is often associated with systemic autoimmune disease. Since the role of monoclonal antibodies in the treatment of autoimmune disorders is not clearly optimized, we evaluated the effectiveness of Rituximab in the treatment of immune neutropenia.

We present two cases (male 66 years and 42 years female) with immune neutropenia, associated with systemic autoimmune disease, Chron’s disease in male patient and rheumatoid arthritis in female patient. Bone marrow biopsy revealed reduction of granulopoesis and absence of neutrophils in the peripheral smear-agranulocytosis. Immunological investigations revealed increased polyclonal IgG, positive indirect granulocyte immunofluorescence test. Both patients had a clinical course with continuously intermittent neutropenia every 2 weeks, presented with recurrent febrile episodes and serious lower respiratory tract infections. Treatment with G-CSF was immediately started in both patients to reach neutrophil recovery, but after one year of periodically persistent neutropenia it was decided to start treatment with Rituximab, an infusion with standard single agent 375 mg/m² weekly for 4 weeks. After 4 infusions neutrophils reached normal levels and the treatment continued with every 2 weeks infusion of monoclonal antibody in duration of 2 months and now once a month as maintenance treatment. The patients are one year and six months after beginning treatment with monoclonal antibodies, in stable clinical and laboratory condition. We can conclude that B cells play a central role in the autoimmune process and Rituximab treatment has been used in patients with autoimmune neutropenia. Further randomized studies will define optimal role of Rituximab in the treatment of autoimmune diseases.