Systemic Juvenile Idiopathic arthritis (still disease)
Adult onset Still disease (AOSD) is a rare systemic inflammatory disorder characterized by daily fever, inflammatory polyarthritis, and a transient salmon-pink maculopapular rash. AOSD is alternatively known as systemic onset juvenile idiopathic arthritis. Even though there is no specific diagnostic test, a serum ferritin level of more than 1000ng/ml is common in AOSD.The etiology of AOSD is unknown. Adult-onset Still disease is a very uncommon disease. Its annual incidence has been estimated to be 0.1 to 0.4 cases per 100,000 people in Europe. Females are affected slightly more than males. It has bimodal age distribution, the first peak between the ages of fifteen to twenty-five and the second between thirty-six to forty-six. However, about three-quarters of the patients report the onset of disease between sixteen and thirty-five years of age.There are three main patterns of the clinical course of adult-onset Still disease (AOSD) namely monophasic, intermittent, and chronic. The primary clinical features seen in adult-onset Still disease (ASD) are fever, rash, and arthritis or arthralgia. Other common symptoms are myalgia, pharyngitis, lymphadenopathy, and splenomegaly.