To determine the serum levels of soluble adhesion molecules in patients with juvenile idiopathic arthritis (JIA), and to determine whether the levels of these molecules differ between active disease and remission in the same JIA subtype, and whether differences in these levels exist between controls and the three JIA subtypes.
The serum levels of soluble E-selectin (sE-selectin) and soluble intercellular adhesion molecule-1 (sICAM-1) were determined by enzyme linked immunosorbent assay (ELISA) in 40 patients with JIA (12 systemic, 13 polyarticular, and 15 oligoarticular) who had active disease or were in clinical remission and 16 healthy controls. Differences in the levels of adhesion molecules of the same JIA subtype during different disease activity were determined by the paired t test, and differences between the disease and control groups were calculated by one way analysis of variance. A value p<0.01 was considered significant.
During the same disease stage (active or in remission), systemic JIA was associated with a significantly higher sE-selectin level than the oligoarticular JIA subtype, whereas this was not found for sICAM-1. Although the mean levels of sE-selectin and sICAM-1 in active systemic and polyarticular JIA were higher than those in remission, this did not reach statistical significance. The levels of sE-selectin and sICAM-1 of the three JIA subtypes, in both the active stage and clinical remission, were still significantly higher than in normal controls.
Systemic JIA is associated with a higher sE-selectin level than oligoarticular JIA both in active disease and in clinical remission. This may explain why the morbidity of systemic JIA is greater than that of oligoarticular JIA-namely, owing to increased endothelial cell activation. As significantly higher levels of sE-selectin and sICAM-1 were found in the active and remission stages of the three JIA subtypes compared with those in the control group, JIA may recur even when clinical remission has been achieved.