Measurement of C-reactive protein and the erythrocyte sedimentation rate in general practice

Abstract
To evaluate the NycoCard:::CRP test (Nycomed A/S, Oslo, Norway) in relation to ESR in consecutive patients in general practice. NycoCard:::CRP test was also compared with a reference method for CRP quantitation. C-reactive protein and ESR were simultaneously measured in 607 consecutive patients at four community health centres. Four community health centres in southern Sweden. We obtained consistent results in 71% of the cases. In 20% CRP was increased more than ESR, while ESR was increased more than CRP in 9%. CRP was increased in 16% while ESR was below the upper reference limit for age and sex. On the other hand ESR was increased while CRP was below 10 mg/l in five % of the patients. In most of the cases where there was a discrepancy- for example, in infectious diseases-the CRP results were more clear-cut. Using the NycoCard test the CRP concentration can be measured directly in a whole blood sample with the result available within minutes. Comparison of the NycoCard:::CRP test with the reference method for CRP quantitation showed good agreement. In clinical situations with suspected inflammatory diseases, the CRP test appears often to yield more useful results than the ESR. The NycoCard:::CRP test is suitable for use in general practice.