[Adult-Onset Still's Disease, an improbable differential diagnosis: a case report]

Juvenile idiopathic arthritides (JIA) comprehend a heterogeneous group of inflammatory diseases of the joints, with an unknown aetiology, arising within 16 years of age, and lasting more than six weeks. The systemic form, known as Still's disease, represents from 4 to 17% of all the JIA. AOSD (Adult Onset Still's Disease) is a variant of JIA affecting adults, with identical clinical manifestations. Here we describe the case of a 36 year old woman, with a symptomatology characterized by fever, skin rash, arthralgies and lymphadenopathy. The arise of the fever in this case has uncommonly preceded by several weeks the arise of the other signs; this has determined a considerable delay in the diagnosis: Still's disease diagnosis is made hard as it shares its signs and symptoms with several infectious, immunological as well as tumoral diseases. In this case, the blossoming of the laboratory parameters at the sixth day of hospitalization with leucocytosis and neutrophilia represented the solving clue. Still's disease, though a rare nosographic entity, must be kept into consideration in unclear cases occurring in an internal medicine department.