Polymerase chain reaction for Enterococcus faecalis in drain fluid: the first screening test for symptomatic colorectal anastomotic leakage. The Appeal-study: analysis of parameters predictive for evident anastomotic leakage.

ABSTRACT

PURPOSE: With current diagnostic methods, the majority of patients with symptomatic colorectal anastomotic leakage(CAL) is identified approximately 1 week after operation.The aim of this study is to determine whether real-time polymerase chain reaction (RT-PCR) for detection of Escherichia coli and Enterococcus faecalis on drain fluid can serve as a screening test for CAL in the early postoperative phase. METHODS: All patients included in this multicenter prospective observational study underwent left-sided colorectal resection for both malignant and benign diseases with construction of an anastomosis. In all patients, an intra-abdominal drain was placed during operation. During the first five postoperative days, drain fluid was processed for RT-PCR. The quantitative results of the RT-PCR on days 2 to 5 were compared to the results of day 1 in order to detect concentration changes. RESULTS: In total, 243 patients, with both benign and malignant diseases, were included of whom 19 (7.8 %) developed symptomatic CAL. An increase in E. coli concentration was found insignificantly more patients with CAL on day 4 and 5 [p =0.0004; diagnostic odds ratio (DOR) 7.9]. For E. faecalis, this result was found for days 2, 3, and 4 (p <0.003) with highest DOR on day 3 (31.6). Sensitivity and negative predictive values were 92.9 and 98.7 %, respectively, virtually ruling out CAL in case of negative test results on the third postoperative day. CONCLUSION: Quantitative PCR for E. faecalis performed on drain fluid may be an objective, affordable and fast screening tool for symptomatic colorectal anastomotic leakage.