Serum markers of collagen synthesis and degradation in acute respiratory failure patients.

Abstract

Procollagen-derived propeptides reflect the rate of collagen synthesis and type I cross-linked collagen telopeptides (ICTP) collagen I degradation. We studied the collagen metabolism to find out if changes seen in acute respiratory distress syndrome patients are observed in patients with acute respiratory failure (ARF), and whether multiple organ dysfunction (MOD) has impact on it. ARF patients with prolonged hospitalisation at least 21 days were included to the study. Blood samples for serum procollagen aminoterminal propeptide I (PINP) and III (PIIINP), and ICTP measurements were collected at study admission (day 0) and on days 2, 7, and 21. The study population comprised 68 patients. Forty-three patients (63%) developed MOD during the first week. PIIINP levels increased in all patients over time. The increase was slightly more pronounced in patients with MOD. During the first week, the synthesis of PIIINP increased more than PINP, and PINP degradation exceeded its production. By day 21, the balance of collagen metabolites returned to baseline. The collagen metabolism was altered in ARF patients. The first week was dominated by degradation of type I collagen and production of type III collagen, but by day 21, the collagen composition returned to more stable form.