SERUM LEVELS OF SOLUBLE INTERLEUKIN-2 RECEPTOR IN PATIENTS WITH SYSTEMIC LUPUS-ERYTHEMATOSUS AND SYSTEMIC IDIOPATHIC VASCULITIS

Soluble interleukin 2 receptor (sIL2R) may be used as an index of immu ne perturbation. We report on the correlation between the serum levels of sIL2R, as assessed with a sandwich-ELISA, and disease activity in 61 patients with Systemic Lupus Erythematosus (SLE) and in 15 with sys temic idiopathic vasculitis (SIV). The mean levels of sIL2R in SLE and SIV patients were significantly higher than in healthy controls and h igher values were detected in patients with active disease or severe o rgan involvement or infection. We also studied patients with clinicall y silent SLE, characterized by the presence of several immunologic abn ormalities. The sIL2R mean level in this group did not differ from tha t of quiescent SLE patients, suggesting that immunologic alterations a re present even in inactive SLE. Finally, the sIL2R assay showed highe r sensitivity and specificity than most of the common immunologic para meters.