Correlation of serum collagen I carboxyterminal telopeptide concentrations with cutaneous and pulmonary involvement in systemic sclerosis
Allanore, Y.; Borderie, D.; Lemaréchal, H.; Cherruau, B.; Ekindjian, O.G.; Kahan, A.
Journal of Rheumatology 30(1): 68-73
2003
ISSN/ISBN: 0315-162X PMID: 12508392 Document Number: 559956
Objective: Systemic sclerosis (SSc) is characterized by fibrosis involving the skin and various internal organs. Type I collagen (Col I) is the most abundant extracellular matrix protein deposited in cutaneous involvement. We investigated Col I biochemical markers in patients with SSc. Methods: All consecutive patients admitted for SSc over a 9 month period and a healthy control group were investigated. Serum concentrations of the C-terminal telopeptide of Col I (s-CTX-I), C-terminal type I procollagen propeptide (PICP), osteocalcin, and bone alkaline phosphatases (ALP), and urinary concentrations of deoxypyridinoline (u-DPD) and u-CTX-I were determined by ELISA. Results: A total of 33 patients with SSc were included: mean age+-SD was 54+-12 yrs, with a mean disease duration of 5.4+-3.9 years. Sixteen of 33 patients with SSc had s-CTX-I values exceeding the upper limit of normal values of the test and the mean+-SEM was significantly higher (7388+-1422 pmol/l) than in healthy controls (2800+-1120 pmol/l; p<0.001). s-CTX-I correlated with the Rodnan skin score (p=0.003); it was higher in patients with diffuse disease (8459+-3125; n=14) than in patients with the limited form (6453+-1235; n=19; p<0.02). This marker also correlated with acute phase reactants (C-reactive protein, p=0.004; erythrocyte sedimentation rate, p=0.02). s-CTX-I was high in patients with positive antitopoisomerase I autoantibodies (p=0.04) and in patients with a decrease in forced vital capacity to less than 75% (p=0.02). u-DPD concentration was high in patients with SSc (10.6+-1.4 nmol/mmol creatinine vs 6.3+-2.1 in controls; p<0.01). No difference between patients and controls or correlations with the disease were found for PICP, u-CTX-I, osteocalcin, and bone ALP concentrations. Conclusion: s-CTX-I, a marker of Col I degradation, is correlated with cutaneous and pulmonary involvement and with acute phase reactants in patients with SSc. This marker is a good candidate for further evaluation for disease activity and treatment purposes.