Serum sulphydryl levels in early synovitis.

The determination of serum sulphydryl levels has been assessed as a diagnostic/prognostic indicator of rheumatoid arthritis in patients attending an early synovitis clinic. This simple assay has been compared with other test systems including C-reactive protein, plasma viscosity, IgM rheumatoid factor and immune complexes. Results show that a low serum sulphydryl at presentation is a useful prognostic indicator for development of persistent synovitis. Patients with normal sulphydryl levels suffered only mild or transient symptoms. These results suggest that, since stimulated phagocytes generate the oxygen-derived species responsible for sulphydryl oxidation, such cells are active before the patient develops persistent symptoms.