SERUM FERRITIN AND ISOFERRITINS ARE TOOLS FOR DIAGNOSIS OF ACTIVE ADULT STILLS DISEASE

Objective. Still's disease is an acute systemic inflammatory disorder. There are no pathognomonic symptoms or specific laboratory abnormalit ies. Serum ferritin concentration in rheumatoid arthritis together wit h some plasma glycoproteins such as alpha(2)-glycoprotein and C-reacti ve protein are part of the response to inflammation. Ferritin in plasm a is glycosylated and the sialoglycosylated forms increase its microhe terogeneity. Our purpose was to confirm in a large series that high va lues of ferritin can be found in adult Still's disease (ASD) and to se e ifa specific isoferritin can be isolated in this disease compared wi th the other systemic diseases. Methods. Thirty-one sera were investig ated from 11 men and 9 women with ASD and compared with 27 sera from 2 7 patients with systemic diseases. We studied the course of one case o f ASD for 15 months. Serum ferritin was determined by immunoenzymology (Abbott(TM) Ferrizin). The isoferritins were investigated by isoelect ric focussing and the percentage of glycosylation by affinity for conc anavalin A (Con-A). Results. In patients with active ASD, the ferritin levels were higher than in patients with inactive ASD or other system ic diseases: p < 0.001. The glycoforms of ferritin were basic and the proportion of ferritin bound to Con-A was lower than other ASD: p < 0. 001. Conclusions. Serum ferritin levels have a diagnostic value for ac ute ASD. The study of sialylation and abnormalities in the glycosylati on of ferritin helps to discriminate ASD from arthritis or other syste mic diseases. In conclusion, the glycoform of isoferritins and the per centage of glycosylation offers an additional tool for the diagnosis o f Still's disease.