Diagnostic Accuracy of Cartilage Oligomeric Matrix Protein (COMP), for Cartilage Damage in Rheumatoid Arthritis

Background: Cartilage oligomeric matrix protein (COMP), is an extracellular matrix (ECM) non-collagenous glycoprotein that is mainly localized within the cartilage, and also be found in tendon and synovium.Recent studies in west and Asia Pacific region has shown that COMP, is a prognostic marker in Rheumatoid arthritis(RA).

Objective: To correlate serum COMP levels with disease severity and cartilage destruction in rheumatoid arthritis.

Methods: The study was conducted in Department of Pathology and Rheumatology, Ziauddin University Hospital, Karachi from June 2018 to May 2019. Patients were recruited as per American College of Rheumatology (ACR) 2010 classification criteria. The study population consists of 88 healthy subjects and 88 RA patients. Sandwich ELISA technique was used to assess serum COMP level. Other inflammatory markers such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) antibodies like rheumatoid factor, and anti-cyclic citrullinated protein (anti-CCP) were also assessed. Results were analyzed using SPSS-20 and P-value ≤0.05 was considered as significant.

Results: Serum COMP levels were significantly higher in RA patients 51.35 ng/ml than controls 21.454 ng/ml with significant p value=<0.0001. There was strong positive correlation between COMP level and disease severity in RA patients with moderate as well as high disease activity score (DAS) with significant p value. Serum COMP showed 96% sensitivity and 83% specificity at level of 27.01 ng/ml for diagnosis of RA.

Conclusions: COMP has significant positive correlation with severity of RA. Serum COMP can be utilized as a biomarker to quantify cartilage destruction in RA patients.