Résumé : A 17-year-old buy presented with fever, bilateral conjunctival infection, angina and extensive cervical adenopathy, Amoxycillin was started. Ten days later he was admitted to hospital because of persistant high fever, cervical adenopathy, erythrema of the pharynx and tongue and lip fissuration. The most important interventions of his first hospitalization were endotracheal intubation because of increasing dyspnoea due to adult respiratory distress syndrome and haemodialysis for renal insufficiency. His admission to our hospital was marked by the echocardiographic discovery of giant coronary aneurysms in the first few centimeters of both right and left coronary arteries. Coronary angiography confirmed giant aneurysm formation of the right and left coronary arteries. Similarly, medium sized arteries (cerebral, hepatic, mesenteric, iliac) presented abnormalities on angiography. Kawasaki syndrome was the final diagnosis, based on clinical presentation, coronary artery abnormalities and laboratory findings. This is the first description of adult-onset Kawasaki disease with giant coronary aneurysm formation and more generalized arterial involvement. The severity of the clinical symptoms and the severity of the coronary disease indicates that Kawasaki disease of the adult does not always have a benign course.