Abstract
Adult-onset Still's disease (AOSD) is characterized by fever, rash, and joint pain and may lead to chronic arthritis. The cause of AOSD is unknown, and it is rare. In children, Still's Disease is called systemic juvenile rheumatoid arthritis. We encountered a patient with adult-onset Still's disease following a severe sore throat and fever. The patient was a 17-year-old woman who consulted our hospital because of a sore throat and fever. She was admitted and treated with antibiotics, but the fever persisted. Laboratory parameters of inflammatory activity increased at an accelerated rate, and after ruling out sepsis, EBV-associated disease, and malignant lymphoma, a diagnosis of AOSD was made. Steroid therapy was very effective. When acute pharyngitis is observed in association with significant changes in laboratory parameters despite mild local symptoms, or when pharyngitis is observed in association with joint pain, continuous fever, and a rash, it is important to consider AOSI).