Aseptic Meningitis-retention Syndrome Associated with Tocilizumab in a Patient with Idiopathic Multicentric Castleman Disease

This is the first report of tocilizumab-associated meningitis-retention syndrome in a patient with idiopathic multicentric Castleman disease. A 57-year-old man presented with headache, nuchal rigidity, impaired consciousness, pyramidal tract signs and urinary retention. A cerebrospinal fluid examination revealed increased cell counts and protein levels. These symptoms were improved by intravenous methylprednisolone. Tocilizumab-associated meningoencephalitis has been reported in patients with rheumatoid arthritis and juvenile idiopathic arthritis but not with multicentric Castleman disease. This case presents evidence of the increased probability of meningitis as a neurological complication of tocilizumab administration.