Background
Multiple sclerosis (MS) is an immune mediated inflammatory disease of the central nervous system (CNS). Lymphocytes play a key role in the pathogenesis of MS. Due to the critical role of B lymphocytes in MS pathology, monoclonal antibodies targeting such cells have been proposed for MS treatment.(1) Rituximab, a monoclonal antibody against CD20 receptors on B lymphocytes, is now being widely used for autoimmune diseases such as MS, rheumatoid arthritis, and cancer therapy, and has had comparable clinical outcomes in managing MS than other injectable and oral disease modifying therapies (DMTs). (2) Therefore, rituximab is being prescribed by medical practitioners for MS therapy in certain countries.(1)
Infections and mild to moderate infusion related reactions are more common side effects of rituximab, and life threatening complications such as anaphylaxis appear to be less frequent. An important side effect of rituximab is cytokine release syndrome (CRS) characterized by rash, fever, mental status changes, etc.(3,4). CRS has been reported in MS patients treated with monoclonal antibodies such as alemtuzumab, however, rituximab induced CRS in MS patients is extremely rare.(5)