ESR or CRP, which inflammatory measure can accurately replace clinical measures in rheumatoid arthritis?

Background ESR and CRP are two commonly used laboratory inflammatory parameters. The controversy remains which of the two is a better measure to use and which parameter closely reflects the clinical measures of inflammation as well the disease process in Rheumatoid arthritis. Methods We used mountain plot analysis to find out the congruency of ESR and CRP individually with clinical measures namely Tender joint count (TJC), Swollen joint count (SJC) and Visual analogue scale for Pain (VAS). 303 RA patients who are in our regular follow-up were included in the study. There TJC, SJC and VAS pain and ESR and CRP were retrieved. Results 242 were female and 61 were male patients. The mean age was 46.8 years (17–79 years), mean duration of illness was 70.81 (3–307) months. All of them were on conventional DMARD with majority on combination of methotrexate, Hydroxychloroquine and/or leflunomide. Both ESR and CRP correlated with all three measures such as TJC, SJC and VAS. The correlation was stronger with ESR than CRP. When the effectiveness of ESR vs CRP was compared for their overlapping on the clinical parameters TJC, SJC and VAS by using mountain plot method, CRP performed better than ESR and coincided with all three clinical parameters of the disease RA. Conclusion Our study emphasizes the fact that CRP is a better measure of inflammation than ESR and represents the information on the inflammatory component provided by both TJC and SJC, as appreciated by the close overlap. The CRP can replace the clinical measures (joint counts and Pain scale) more effectively than ESR, provided other causes for elevation of CRP are excluded.