A TRIAD OF FEATURES: Adult onset Still's disease (ASD) is an uncommon disorder usually associating high spiking fever, evanescent skin rash constituted of small salmon pink macules, and arthritis. NUMEROUS SYSTEMIC MANIFESTATIONS: A sore throat is common and often misleading. More than 60% of the patients develop mobile and indolent lymph nodes, usually in the cervical area. Liver involvement is common and usually limited to a mild or moderate cytolysis. However, several observations of severe hepatitis have been reported justifying strict monitoring of the liver biology in these patients. Amongst the other numerous systemic manifestations that have been reported, pericarditis is common and sometimes responsible for tamponade, the pulmonary involvement may lead to an acute respiratory distress, and the rare neurological manifestations include aseptic meningitis or cranial nerve palsy. FROM A BIOLOGICAL POINT OF VIEW: The sedimentation rate is consistently elevated and there is usually a marked elevation in the polymorphonuclears. The bacteriological survey is negative as are the immunological tests. An increase in the serum level of IL-18 might be both diagnostic and prognostic. It is the increase of the serum level of ferritin and the marked decrease in its glycosylated fraction below 20% that seem to be of more potent diagnostic value.