Recurring Anastomotic Leak-A Prospective Clinicopathological Investigation of a Distinct Disease Pattern.

BACKGROUND: Intestinal anastomotic insufficiency (AI) is a common problem in visceral surgery associated with overexpression of matrix metalloproteinases (MMPs). In some patients it occurs more than once. The etiology of recurring anastomotic insufficiency (RAI) is not understood yet and should be addressed as an independent disease entity. MATERIALS AND METHODS: Thirty nine consecutive patients with AI were treated at our university center and were included in this prospective study. Clinical data were evaluated by correlative statistical analysis to identify independent risk factors for RAI. Patients were divided in two groups: 18 patients had a single operative revision until restoration (group SAI), and 21 patients had two or more revisions (group RAI). Anastomotic tissue samples as well as untouched bowel wall were collected during reoperations for analysis of MMPs and tissue inhibitor of metalloproteinases (TIMP2). Clinical data were correlated with pathological observations. RESULTS: Significant differences of clinical and molecular pathological data were found between the two groups. Transfusion of red blood cells until the first reoperation and alcohol abuse led to RAI and were the only independent risk factors for RAI in multivariate analysis. Overexpression of MMP-8, -9, and -13 in anastomotic tissue correlated with the administration of red blood cells during initial operation. Reduced expression of TIMP2 was frequent in nearly all patients without differences throughout the subgroups. CONCLUSIONS: RAI seems to have an independent disease pattern. Transfusion of blood products is not only a known risk factor for AI but seems to significantly disturb the anastomotic healing process leading to RAI.