C-reactive protein: the best laboratory indicator available for monitoring disease activity.

Recent technical advances in measurement of serum C-reactive protein (CRP) have made this laboratory test highly specific, sensitive, reproducible, quantitative, and easy and rapid to perform. Several studies have shown that serial and quantitative measurement of serum CRP can be very helpful in monitoring disease activity in a wide variety of clinical situations, and that CRP testing offers distinct advantages over testing for any of the other acute-phase reactants. CRP testing is superior to erythrocyte sedimentation rate (ESR) measurements on clinical, scientific, and practical grounds, and it is strongly recommended that serious consideration be given to replacing ESR with CRP testing for monitoring disease activity.