Central nervous system inflammatory demyelination after rituximab therapy for idiopathic thrombocytopenic purpura.

A 53-year-old female developed unilateral shoulder girdle pain, entire body paresthesiae and imbalance starting 10 days after completing a course of rituximab for chronic idiopathic thrombocytopenic purpura. Neuroimaging studies showed inflammatory demyelinating lesions of the cervical spinal cord and cerebellum. Immunocytochemistry of spinal fluid lymphocytic pleocytosis showed an absolute B cell depletion and a polyclonal/inflammatory T cell response. Intravenous immunoglobulin infusions were associated with clinical and radiological improvements. Anti-CD20-therapy possibly resulted in an imbalance between B cell and T cell populations in the central nervous system, and may have triggered a predominantly cell-mediated immune attack against unidentified nervous system antigens.