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

Abstract

Objective - To evaluate the NycoCard::: CRP test (Nycomed A7S, 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. Design - C-reactive protein and ESR were simultaneously measured in 607 consecutive patients at four community health centres.

Setting - Four community health centres in southern Sweden.

Results - 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/1 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. Conclusion - 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.

Key Words:

• C-reactive protein
• erythrocyte sedimentation rate
• general practice
• inflammatory diseases
• infections