title: Nonvasculitic autoimmune meningoencephalitis after rituximab: the potential downside of depleting regulatory B cells in the brain.
abstract: Nonvasculitic autoimmune meningoencephalitis (NAIM) is a rare condition describing a syndrome of steroid-responsive encephalopathy in patients with similar clinical and pathologic features. It can be associated with autoimmune diseases, such as Sjogren's syndrome and autoimmune thyroiditis. Brain biopsies usually show inflammatory cells without evidence of vasculitis. In this article, we present a patient who developed NAIM after receiving rituximab, a B-cell-depleting therapy for rheumatoid arthritis. The brain biopsy showed a lack of B lymphocytes in the brain tissue, and the patient responded well to intravenous immunoglobulins. We further discuss the role of B lymphocytes and specific regulatory B lymphocytes in suppressing autoimmunity in the brain and propose that the depletion of regulatory B cells may contribute to the pathogenesis of NAIM. This case illustrates a potential side effect of rituximab and demonstrates the importance of regulatory B cells in maintaining the immune response.
authors.affiliation: From the *John H. Stroger Jr. Hospital of Cook County, Chicago, IL; Departments of †Medicine, and ‡Pathology, Rush University School of Medicine, Chicago, IL; and §Department of Medicine, The University of Pennsylvania Penn Tower, Philadelphia, PA.
authors.forename: Indira
authors.initials: I
authors.lastname: Hadley
authors.forename: Richa
authors.initials: R
authors.lastname: Jain
authors.forename: Antoine
authors.initials: A
authors.lastname: Sreih
mesh_terms: D000368:Aged; D058846:Antibodies, Monoclonal, Murine-Derived / Q000009:adverse effects* / Q000494:pharmacology / Q000627:therapeutic use; D018501:Antirheumatic Agents / Q000009:adverse effects* / Q000494:pharmacology / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000188:drug therapy; D001327:Autoimmune Diseases / Q000139:chemically induced* / Q000175:diagnosis; D060151:B-Lymphocytes, Regulatory / Q000187:drug effects / Q000473:pathology*; D001706:Biopsy; D001921:Brain / Q000473:pathology*; D005260:Female; D006801:Humans; D007111:Immunity, Cellular / Q000187:drug effects; D016756:Immunoglobulins, Intravenous / Q000494:pharmacology / Q000627:therapeutic use; D008590:Meningoencephalitis / Q000139:chemically induced* / Q000175:diagnosis; D000069283:Rituximab; D016896:Treatment Outcome
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D018501:Antirheumatic Agents; D016756:Immunoglobulins, Intravenous; D000069283:Rituximab