Livello sierico della COMP (Cartilage Oligomeric Matrix Protein): Uso potenziale come marker di progressione del danno articolare nei pazienti con "Early Rheumatoid Arthritis"

Background. Recent studies advice that the serum concentration of cartilage oligomeric matrix protein (COMP) in patients suffering from rheumatoid arthritis (RA) is a marker of progression of cartilage destruction. Nevertheless, even though these evidences, the practical use of this biochemical marker to predict tissue destruction is still limited. The aim of the work was to study the possible contribution of COMP in the valuation of the level of the progression of structural damage, estimated by contrast RMN, in patients with RA in the first year of disease. Methods. 16 patients with RA were studied, according with ACR criteria of the 1988; the onset of the disease was less than 6 months ago. Out of each patient, the age, the sex, and the disease duration from the start of the articular symptoms were established at the beginning and after 6 months. A clinic-biohumoral and instrumental evaluation was also effected and registered. Serum samples were collected twice to perform the hematologic and serum routine, and to measure COMP levels with commercial kit "COMP ELISA" (AnaMar Medical, Lund, Sweden). Results. The patients studied were divided in two groups according to the presence/absence of early erosion. The 75% of the patients showed already erosive lesions at the RMN at the beginning of the disease. The basal serum level of COMP was higher in the group with early erosion. The correlation between the basal serum level of COMP and the RMN score about the bone erosions was significant statistically at the beginning and after 6 months. The correlation between the variations of serum levels of COMP was also significant statistically (δ RMN erosions 6 months vs basal) (r = 0,63; p = 0,0079). There were not correlations between the variations of RMN erosive score and the variations of clinical-biohumural parameters of inflammation. Conclusions. From our study seems that the absence of an increase of serum level of COMP in patients with early rheumatoid arthritis, independent of variation of inflammatory, clinical, and biohumural markers, guarantees from the progression of the structural articular damage. Therefore we could suppose the future use of this marker to evaluate an individual answer at the pharmacological treatment, inducing to choose "aggressive" therapeutic plans in the patients with high risk of cartilage destruction.