Serum C-reactive protein in polymyalgia rheumatica. A prospective serial study.

A prospective serial study of 13 well-documented, previously untreated cases of polymyalgia rheumatica was undertaken in order to assess the behavior of the nonspecific indices of disease activity, erythrocyte sedimentation rate and serum C-reactive protein (CRP) concentration, during induction of disease remission by prednisolone therapy. The clinical manifestations of all patients responded rapidly and completely to steroids, and the serum CRP value, which was raised in all patients at presentation, fell to normal at a rate which precisely reflected the clinical improvement. The erythrocyte sedimentation rate also fell, but did so much more slowly than the CRP concentration and, in half the patients, was still not normal after 14 days. These results indicate that assay of serum CRP provides a precise means of objectively assessing the course of polymyalgia rheumatica during initial therapy with steroids, and suggest that routine measurements of CRP may make a useful contribution to the management of the disease.