Background: Rituximab has been increasingly prescribed in the treatment of multiple sclerosis (MS) over recent years. Tumefactive demyelinating lesions can occur at the onset or over the course of MS. Another major cause of these lesions is the side effects of drugs such as natalizumab or fingolimod. This study is a case report of a young MS patient who suffered from tumefactive lesions following the injection of rituximab.
Case presentation: The patient was an 18-year-old man with MS who developed double vision, imbalance, and quadriparesis symptoms followed by a decrease in his consciousness two days after administration of rituximab. Tumefactive lesions were observed in the patient's brain magnetic resonance imaging (MRI).
Conclusion: Rituximab should be considered as a potential cause of tumefactive demyelinating lesions in patients with MS.
Keywords: Multiple Sclerosis Rituximab.; Tumefactive demyelinating lesions.