[Soluble interleukin-2 receptor assay is unhelpful in chronic inflammatory rheumatism]

The level of soluble interleukin-2 receptors (SIL2-R), which reflects lymphocyte activation, is often described as a useful parameter for evaluating disease activity and progression in patients with inflammatory conditions. Serum SIL2-R was assayed using a sandwich ELISA method in 98 subjects including 38 controls (C), 36 patients with ankylosing spondylarthropathy (AS) and 24 patients with rheumatoid arthritis (RA). SIL2-R levels were higher in RA patients than in controls and AS patients (p < 10(-4)), whereas the difference between AS patients and controls was small (p = 0.02). In RA patients, SIL2-R levels were not correlated with any of the clinical or biological parameters studied and remained unchanged during clinical improvements. In the AS group, SIL2-R levels showed no correlations with inflammation parameters (CRP, IgA) and was similar in patients with and without HLA B27 or appendicular joint involvement. This study failed to provide any evidence that SIL2-R levels are helpful for monitoring patients with inflammatory joint disease.