Organic brain syndrome in rheumatoid arthritis following corticosteroid withdrawal.

Six patients with seropositive nodule-forming rheumatoid arthritis developed severe central nervous system manifestations consistent with a diagnosis of organic brain syndrome. Organic brain syndrome occurred while 5 of these patients were undergoing corticosteroid withdrawal after prolonged administration. Neuropsychiatric symptoms rapidly cleared, responding to reinstitution of oral or parenteral corticosteroids in large doses in 4 patients, to increase in dosage in 1 patient, and to no drug therapy in the remaining 1. Marked reduction in rheumatoid factor in sera and demonstration of IgM deposits in the choroid plexus in 1 of the patients raised the possibility of immune complex-mediated central nervous system vasculitis.