Naproxen–induced aseptic meningitis in a woman with synovitis–acne–pustulosis–hyperostosis–osteitis syndrome

Abstract

A 33–year–old woman with synovitis–acne–pustulosis–hyperostosis–osteitis (SAPHO) syndrome developed non–throbbing headache. She was permitted to take a tablet of naproxen by her doctor in advance when being febrile or having a headache due to SAPHO syndrome. She took a tablet of naproxen as usual, but her headache was getting worse. In the next day, she developed not only severer headache, but also impaired consciousness, nausea, and vomiting. Neurological examinations revealed abnormal fluctuation of consciousness level and meningeal signs. Blood tests showed severe inflammatory reaction, and cerebrospinal fluid tests showed pleocytosis with polymorphonuclear predominancy and an elevated level of protein. Discontinuation of naproxen rapidly diminished her symptoms and signs. After exclusion of other possible diagnoses, we finally diagnosed her as naproxen–induced aseptic meningitis. Nonsteroidal anti–inflammatory drugs are recognized as a possible cause of drug induced aseptic meningitis (DIAM), but naproxen–induced aseptic meningitis is extremely rare in Japan. Allergic reaction against the dura associated with the autoimmune abnormality based on SAPHO syndrome is suggested as the main mechanism of DIAM in this case.