[ Serum osteocalcin in chronic polyarthritis in stage III]

Osteocalcin, a major noncollagenous protein component of bone matrix which reflects the level of new bone formation, was measured in serum by radioimmunoassay, in 45 patients with rheumatoid arthritis (RA) (Steinbrocker stage III) and in 45 age- and sex-matched healthy subjects. According to the literature, serum osteocalcin concentrations were slightly decreased in the RA group but this was not statistically significant. Only RA patients on corticosteroid therapy had statistically significant decreased osteocalcin levels, compared with normal controls. No correlation was determined in the RA patients between serum osteocalcin levels and levels of C-reactive protein, erythrocyte sedimentation rate, circulating immune complexes (Clq binding assay) and rheumatoid factors of the IgA, IgG or IgM class.