Collagen metabolites in the peripheral and splanchnic circulation of patients with Crohn disease

Fragments of collagen arising during synthesis and breakdown have been sugg ested as markers of fibrous tissue remodelling in Crohn disease. We compare d serum concentrations of the C-terminal propeptide of collagen I (PICP), t he N-terminal propeptide of collagen III (PIIINP) and the C-terminal telope ptide of type I collagen (ICTP) in the splanchnic and systemic circulation in Crohn disease requiring segmental intestinal resection. Method: 15 conse cutive patients undergoing surgery due to strictures or continuous inflamma tion. Male:female ratio was 6:9. Blood was drawn from a peripheral vein pri or to surgery. Immediately before intestinal resection, additional samples were drawn from the antecubital vein and from a mesenteric vein draining th e affected intestinal segment. PIIINP, PICP and ICTP were measured with rad ioimmunoassays. Results. Pre-surgery S-ICTP (median 5.5 mug/L; range 3.2-17 .2 mug/L) was significantly increased in peripheral blood compared with hea lthy controls (median 2.6 mug/L; range 0.6-5.7 mug/L), P less than or equal to 0.05. By contrast, S-PICP (median 98 mug/L: range 62-137 mug/L) and S-P IIINP (median 2.5 mug/L; range 1.2-7.4 mug/L) were significantly lower than S-PICP (median 133 mug/L; range 66-284 mug/L) and S-PIIINP (median 3.4 mug /L. range 1.0-7.1 mug/L) in healthy controls, P less than or equal to0.05. During surgery, no difference in S-PICP and S-PIIINP was documented between peripheral blood and splanchnic blood. In contrast, S-ICTP was increased i n splanchnic blood (median 6.2 mug/L; range 2.7-17.4) compared to periphera l blood (median 5.0 mug/L; range 3.1-13.4) (P = 0.05). Conclusion: The pres ent study provides further evidence that the altered intestinal collagen me tabolism in Crohn disease is reflected in the local and systemic circulatio n.