[The clinical significance of the measurement of serum soluble interleukin-2 receptors in various diseases].

We measured the serum levels of soluble interleukin-2 receptor (sIL-2R) in patients with collagen disease, viral hepatitis, and chronic renal failure on hemodialysis (HD) by enzyme immunoassay. sIL-2R levels were significantly higher in patients with collagen diseases (rheumatoid arthritis (RA), 843 +/- 509; systemic lupus erythematosus (SLE), 774 +/- 308; Sjögren's syndrome (SjS), 760 +/- 288; progressive systemic sclerosis (PSS), 649 +/- 198U/ml), with the viral markers of hepatitis B or C (HBsAg positives, 911 +/- 589; anti-HCV positives, 664 +/- 455U/ml) or with chronic renal failure on HD(1,431 +/- 406U/ml) than in the controls (302 +/- 57U/ml). In RA patients, there was a significant positive correlation between sIL-2R level and Lansbury's Indice or serum rheumatoid factor level. Patients with viral hepatitis showed a significantly positive correlation between the sIL-2R level and the level of ZTT or TTT. There was a significant difference between the HD patients with the anti-HCV antibody and those without, and between those with the anti human T lymphotrophic virus-I (HTLV-I) antibody and those without. In addition, there was a significant positive correlation between the sIL-2R level and duration of HD. These findings suggest that sIL-2R is a useful marker for disease activity in collagen diseases, especially in RA, and chronic viral infection such as HBV, HCV or HTLV-I in HD patients.