title: A Case of Adult Onset Still's Disease Misdiagnosed as Septic Arthritis.
abstract: We present a case of adult onset Still's disease (AOSD) that was misdiagnosed as septic arthritis of the shoulder and knee. A forty-nine-year-old woman was admitted for pain in the left knee. The patient's medical history showed that she had undergone arthroscopic irrigation twice and an open debridement under the diagnosis of septic shoulder at another hospital. The laboratory and joint fluid analysis findings led us to suspect septic knee. Arthroscopic irrigation and antibiotics treatment were performed. At five weeks after discharge, she presented with pain in the same joint, fever, and rash. The symptoms were consistent with Yamaguchi's criteria for AOSD. We started corticosteroid therapy, and clinical remission was achieved. In conclusion, we suggest that AOSD should be considered as a diagnosis of exclusion to avoid misdiagnosis with septic arthritis.
authors.affiliation: Department of Orthopaedic Surgery, Kyung Hee University College of Medicine, Seoul, Korea.
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Song
authors.forename: Dae Kyung
authors.initials: DK
authors.lastname: Bae
authors.forename: Jung Ho
authors.initials: JH
authors.lastname: Noh
authors.forename: Geon Wook
authors.initials: GW
authors.lastname: Seo
authors.forename: Dong Cheol
authors.initials: DC
authors.lastname: Nam