Abnormal primary tissue collagen composition in the skin of recurrent incisional hernia patients.

Recurrence of incisional hernia may be as high as 50 per cent. Abnormal collagen I/III ratios have been observed within scar tissue of patients with recurrent incisional hernias. We sought to determine whether collagen composition in primary, nonscarred tissue was similarly affected in these patients. In this prospective, case-control study, nonscarred, primary abdominal wall skin and fascia biopsies were obtained in 12 patients with a history of recurrent incisional hernias and 11 control subjects without any history of hernia while undergoing abdominal laparoscopic surgery. Tissue protein expression of collagen I and III was assessed by immunohistochemistry followed by densitometry analysis. The collagen I/III ratio in skin biopsies from the recurrent hernia group was significantly less compared with control subjects (0.88 +/- 0.01 versus 0.98 +/- 0.04, respectively, P < 0.05). Fascia biopsies from patients with recurrent hernias was not significantly decreased in collagen I/III ratio compared with control subjects (0.90 +/- 0.04 versus 0.94 +/- 0.03, respectively, P = 0.17). Decreased collagen I/III ratios within the skin of patients with recurrent hernias not involved with scar or healing tissue suggest an underlying collagen composition defect. Such a primary collagen defect, in addition to abnormal scar formation, likely plays a significant role in the pathogenesis of recurrent incisional hernias.