Circulating collagen metabolites in systemic sclerosis. Differences between limited and diffuse form and relationship with pulmonary involvement.
OBJECTIVE
To study collagen metabolites in systemic sclerosis (SSc) and their relationship with clinical manifestations of the disease.


METHODS
Forty-eight SSc patients, 13 with a diffuse form (dcSSc), 23 with a limited form (lcSSc) and 12 with suspected SSc not fulfilling the ACR criteria, and 31 healthy controls were examined. Serum concentrations of aminoterminal type III procollagen peptide (PIIINP), aminoterminal and carboxyterminal type I procollagen peptides (PINP and PICP) and cross-linked carboxyterminal telopeptide of collagen I (ICTP) were determined by radioimmunoassay.


RESULTS
Increased serum concentrations of ICTP were found in SSc patients compared with controls. Distinctly higher levels of ICTP were observed in dcSSc than in lcSSc. High serum ICTP was correlated with skin score and acute phase reactants, and with reduced pulmonary function. Serum PIIINP concentration was elevated in both lcSSc and dcSSc.


CONCLUSIONS
Augmented collagen catabolism accompanies the increased collagen synthesis in SSc. Serum ICTP concentration is a marker of this feature and also reflects clinical severity.
Scheja
A
A
Department of Rheumatology, University Hospital, Lund, Sweden.
Wildt
M
M
Wollheim
F A
FA
Akesson
A
A
Saxne
T
T
D000328:Adult; D000368:Aged; D003094:Collagen / Q000032:analysis / Q000378:metabolism*; D024042:Collagen Type I; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000097:blood; D010455:Peptides / Q000032:analysis; D011347:Procollagen / Q000097:blood; D012594:Scleroderma, Localized / Q000378:metabolism* / Q000503:physiopathology; D012595:Scleroderma, Systemic / Q000378:metabolism* / Q000503:physiopathology
D024042:Collagen Type I; D010446:Peptide Fragments; D010455:Peptides; D011347:Procollagen; C052929:collagen type I trimeric cross-linked peptide; C047202:procollagen Type I N-terminal peptide; C041876:procollagen Type III-N-terminal peptide; C042813:procollagen type I carboxy terminal peptide; D003094:Collagen