A case of rheumatoid meningitis: pathologic and magnetic resonance imaging findings.

Central nervous system (CNS) involvement is extremely rare in patients with rheumatoid arthritis (RA). Additionally, most patients with CNS involvement have chronic and severe RA. We present a report of a 66-year-old man who was diagnosed with rheumatoid meningitis and CNS vasculitis without a history of RA. His initial symptom was seizure. Brain magnetic resonance imaging showed leptomeningeal enhancement.CSF analysis revealed slight increase in the number of white blood cells. An examination of viral markers and culture studies for infectious etiology were unremarkable. However, the rheumatoid factor was positive and the levels of anti-cyclic citrullinated peptide antibody were very high. The patient was diagnosed with rheumatoid meningitis and received steroid therapy. However, he developed CNS vasculitis. We suggested that the possibility of rheumatoid meningitis should be considered during the differential diagnosis stage in patients with uncontrolled meningitis, even though RA does not typically show CNS involvement.