Soluble interleukin-2 receptor in primary and secondary Sjögren's syndrome.

Serum levels of soluble interleukin-2 receptor (sIL2-R) were studied in patients with or without Sjögren's syndrome (SS). The mean sIL2-R level was significantly higher (P < 0.0001) in those with autoimmune diseases, whether with or without SS, than in healthy people. The serum level of sIL2-R did not help to distinguish primary from secondary SS, or the absence of this syndrome in patients with autoimmune diseases. We found a correlation between the sIL2-R level and the presence of SS-A and SS-B antibodies or antinuclear antibody levels, and no correlation with other serological and clinical markers. Salivary gland anomalies were always accompanied by high sIL2-R levels, but there was no correlation between sIL2-R levels and degree of glandular lesion. Routine determination of sIL2-R in patients with dry syndrome is likely to prove useful for ruling out SS without resorting to invasive testing.