Collagen distribution and expression of matrix metalloproteinases 1 and 13 in patients with anastomotic leakage after large-bowel surgery.

Abstract

Despite improved surgical techniques, anastomotic leakage is still a serious complication in colorectal surgery, resulting in increased morbidity and mortality. Based on recent studies showing a disturbance of the collagen synthesis in hernia patients, this pilot study was designed to find out whether there are any hints of disorders concerning the collagen metabolism in patients developing anastomotic leakage after colonic surgery. Ten samples of colonic tissue from patients who developed anastomotic dehiscence after surgery for colonic cancer were compared with 14 specimens from patients with uncomplicated anastomotic healing. All samples were obtained at the primary operation. We performed a sirius red test for the overall collagen content and immunhistochemical studies facing differentiation between collagen I and III and the expression of MMP-1 and MMP-13. In the bowel sections from patients developing anastomotic leakage, decreased levels of collagen I and III, and a smaller amount of overall collagen were found. The ratio of collagen I:III was similar in both groups. While MMP-1 was expressed in all samples, there was a difference concerning the expression of MMP-13. In only 6 of 14 patients with uncomplicated healing was MMP-13 present, while in 9 of 10 patients developing a leakage. Our data may indicate the presence of an individual disturbance of the collagen metabolism in patients developing a leakage after colorectal surgery. Further studies are underway to define more precisely whether a preexisting impairment of wound healing could be a risk factor for anastomotic leakage.