Adult onset Still's disease (AOSD) is an uncommon, systemic, inflammatory disorder of unknown etiology, characterized by the triad of fever, arthritis and rash.
We describe 8 cases of AOSD (3 male, 5 female) diagnosed and treated in the Department of Rheumatology from 1980 to 1996. The delay in reaching a firm diagnosis was between 2 and 86 months, due to both lack of specific serum markers and the abundance of possible differential diagnoses. Our therapeutic strategies and results are presented and the value of obtaining serum ferritin levels for both diagnosis and follow-up studies is discussed. The patients data are compared to those of the world's literature on AOSD.
The differential diagnosis of fever of unknown origin should always include AOSD, because these patients could be spared from invasive and unnecessary diagnostic measures. Increased serum ferritin levels are of particular value in the diagnosis of acute AOSD and the normalization of the serum ferritin value is a reliable indicator of therapeutic success.