Ear and Nose Abnormalities in Meningoencephalitis Associated With Relapsing Polychondritis: A Case Report

Relapsing polychondritis (RPC) is a rare autoimmune disease that affects cartilage and connective tissue, especially the ear and nose. The diagnosis of relapsing polychondritis is challenging due to its low incidence, and cases with meningoencephalitis as the predominant manifestation are particularly difficult to identify. We report a case of meningoencephalitis associated with relapsing polychondritis. A 67-year-old woman who had a 1.5-month history of fever, acute impaired consciousness, and nuchal rigidity was diagnosed with aseptic meningoencephalitis of uncertain etiology and referred to our hospital. Cerebrospinal fluid (CSF) analysis revealed pleocytosis and high levels of interleukin-6 (IL-6). Head magnetic resonance imaging (MRI) revealed a meningeal enhancement. Her ear and nose deformities were noted, and a biopsy from her pinna was conducted. Based on the histological findings, relapsing polychondritis was diagnosed with central nervous system (CNS) involvement. The symptoms were partially relieved by immunotherapy, and intrathecal interleukin-6 decreased. She has significantly improved and was discharged six months after the initiation of treatment. Since the most frequent clinical manifestation of relapsing polychondritis is auricular chondritis, this finding can become a clue to diagnosis. Neurologists, upon the diagnosis of meningoencephalitis of unknown cause, should carefully examine for nasal and, especially, ear abnormalities, considering the potential for central nervous system involvement in relapsing polychondritis.