Meningoencephalitis in relapsing polychondritis: A case report.

RATIONALE: Aseptic meningoencephalitis is a rare central nervous system complication of relapsing polychondritis (RP). PATIENT: We report a 61-year-old Japanese male patient with spiking fever and impaired consciousness. Neurological examination revealed meningealirritation, and cerebrospinal fluid (CSF) examination showed lymphocytic pleocytosis with elevated protein (199 mg/dL) and interleukin-6 (3810 pg/mL). Serological analysis showed high levels of anti-type II collagen antibodies, and the result of auricular biopsy was consistent with the diagnosis of RP showing cartilage degeneration surrounded by inflammatory cell infiltrations. DIAGNOSIS: A clinical diagnosis of RP was made according to the diagnostic criteria established by MacAdams et al. INTERVENTION: Steroid pulse therapy (methylprednisolone 1000 mg, consecutive 3 days) followed by oral prednisolone (60 mg/day) resolved the patient's high fever and disturbance of consciousness. OUTCOMES: The patient rapidly improved after steroid treatments and has a normal quality of life under the maintenance dose of steroid plus methotrexate (4 mg/week). LESSONS: RP-associated meningoencephalitis is a rare complication with significant morbidity and mortality. It should be considered and differentiated in patients with RP with unexplained spiking fever and impaired consciousness. In addition, the assessment of cerebrospinal fluid interleukin-6 levels may be useful to investigate the disease activity of RP-related meningoencephalitis. Further prospective studies are required to confirm this result.