The Value of Procalcitonin in Early Diagnosis of Anastomotic Leak After Colorectal Surgery

BACKGROUND: Anastomotic leakage (AL) is the most feared complication after colorectal surgery, with high morbidity and mortality. Early detection remains challenging, as clinical and radiological signs are often delayed. This study aimed to evaluate the diagnostic value of procalcitonin (PCT) kinetics between postoperative days (POD) 1 and 3 in predicting AL after colorectal surgery. METHODS: A prospective analytical study was conducted from January 2021 to January 2024 at the Department of General Surgery, Trauma and Burns Center, Ben Arous, Tunisia. Patients undergoing colorectal resection with immediate anastomosis were included. Serum levels of white blood cells (WBC), C-reactive protein (CRP), and PCT were measured on POD1 and POD3. The diagnostic performance of each marker and their kinetics was assessed using receiver operating characteristic (ROC) analysis. RESULTS: Among 114 included patients, 11 (9.6%) developed an AL. Significant associations were found with older age (p = 0.038), absence of bowel preparation (p = 0.048), and manual anastomosis (p = 0.013). PCT and CRP levels at POD3 were significantly higher in patients with AL (p < 0.001). The optimal PCT cutoff at POD3 was 3.53 ng/mL (AUC = 0.85; sensitivity = 81%; specificity = 80%). The ΔPCT (POD3-POD1) > 0.51 ng/mL showed the best performance (AUC = 0.94). The combined variable (CRP + PCT at POD3) achieved an AUC = 0.95 and a negative predictive value of 98.9%. CONCLUSIONS: PCT kinetics between POD1 and POD3 are a reliable early predictor of AL after colorectal surgery. Combined monitoring of PCT and CRP improves diagnostic accuracy and may optimize postoperative management.