Objective. To examine the usefulness of determining extended serum cytokine profiles in patients with juvenile rheumatoid arthritis (JRA), for the purpose of improving differential diagnosis and monitoring disease activity.
Methods. In a 2-year prospective study, serum levels of interleukin-lp (IL-lp), soluble IL-2 receptor (sIL-2R), IL-6, IL-8, tumor necrosis factor a (TNFa), and the p55 soluble TNF receptor (sTNFR) were repeatedly determined by enzyme-linked immunosorbent assay in 40 patients with JRA, 13 patients with postinfectious arthropathies, and 30 healthy controls. The data were compared with conventional parameters of inflammation, such as C-reactive protein (CRP), iron and hemoglobin levels, erythrocyte sedimentation rate (ESR), white blood cell (WBC) counts, and platelet counts. WBC subsets were analyzed by flow cytofluorometry.
Results. At the first visit and at the peak of inflammatory activity according to CRP levels andor ESR, serum levels of sIL-~R, IL-6, and sTNFR in JRA patients correlated significantly with conventional inflammation indicators, whereas IL-lp, IL-8, and TNFa did not. No changes in leukocyte subset distribution were noted. Among the different clinical subtypes of JRA, sIL-~R, IL-6, and sTNFR values at the time of the initial visit showed a pattern similar to CRP, whereby patients with systemic disease exhibited by far the