Serum Cartilage Oligomeric Matrix Protein (COMP) in Rheumatoid arthritis: relation to severity and activity of the disease

Abstract

Summary R heumatoid arthritis (RA) is an autoimmune disease that results in chronic systemic inflammatory disorder that may affect many tissues and organs. It can be a disabling and painful condition which can lead to substantial loss of function and mobility if not adequately treated. Early diagnosis of disease and aggressive treatment with tight control of disease activity will decrease the morbidity and mortality of the disease. Early diagnosis of bad prognostic markers is needed to define patients who are at risk of developing erosions and bone damage. Treatment of these patients with tight control of disease activity and regular monitoring will help to avoid bone damage. This study was designed to assess the level of serum Cartilage Oligomeric Matrix Protein (COMP) in rheumatoid arthritis patients and its relation to disease activity and severity in those patients. This study included 40 patients with recent onset rheumatoid arthritis (<I year) who satisfied the ACR/ EULAR classification of RA and whose onset of symptoms started within a year. And 20 healthy subjects, as a normal control group. In the present study the majority of rheumatoid patients were females (90%), their ages ranged from 18-50 with mean SD 34.75 ± 6.90 and mean duration of disease 6.73 ± 3.53.Anti-CCP was positive in 35% and negative in 65% of patients. There was highly significant statistical difference between patients and control groups as regard serum COMP level (P <0.001).and the best cutoff point for serum COMP level was >130ng/ml, with specificity 95% and sensitivity 65%. A highly statistically significant association between serum COMP and DAS 28 CRP (p<0.010), As well high significant positive correlation with SJC 28 (P<0.002) and Significant positive correlation with TJC28 (P<0.029). In this study RA patients were sub grouped according to DAS 28 CRP score into mild ( 2.5%),moderate (32.5%),severe (65%) and a high significance positive correlation was found between serum COMP level and degree of disease activity(p<0.000). A high significance positive correlation was found between serum COMP level and CRP (P<0.010), Anti-CCP (0.009).and significant positive correlation with ESR (P<0.028) and OMERACT score for ultrasonographic changes (p<0.19). On the other hand no correlation was found between serum COMP level with age, sex or disease duration of those patients. And no statistical association was found between serum COMP and patient’s CBC or Larsen score of patient’s radiography.