Early diagnosis of anastomotic leakage in colorectal surgery: prospective observational study of the utility of inflammatory markers and determination of pathological levels.

Procalcitonin (PCT) and C-Reactive Protein (CRP) are acute-phase reactants that indicate the presence and severity of an infection. The aim of this study was to verify the utility of CRP and PCT as tools for early diagnosis of anastomotic leakage (AL) in patients undergoing elective colorectal surgery. A prospective observational study including 95 patients undergoing elective colorectal surgery with anastomosis, where patients were divided into two groups according to whether or not AL happened. Different variables were compared using a uni- and multivariate analyses to identify the risk factors for AL. Receiver Operating Characteristic (ROC) curves were added to establish a cut-off point for CRP and PCT. The inflammatory marker levels were analysed in other complications different from AL. AL was detected in 11 patients (14%), 7 required an emergency reoperation. The overall morbidity rate was 42.1% and the mortality was 3.2%. In the univariate study, increased CRP on days 3 and 5, male sex and intraoperative complications were significantly associated with AL. In the multivariate study, CRP on day 5 was the only factor related to AL. AUC at ROC curves showed that CRP results ≥ 15.3 mg/dL on day 3 and 9.1 mg/dL on day 5 were predictors of AL. Normal CRP and PCT values had a high negative predictive value. CRP on postoperative day 5 is a reliable marker for early detection of anastomotic leakage in colorectal surgery. Both CRP and PCT on days 3 and 5 have a high negative predictive value.Trial registration: The study has been registered at ClinicalTrials.gov. Code: NCT04632446.