Procalcitonin and C-reactive protein: markers in the early diagnosis of anastomotic leak.

Objective: To determine the efficacy of serum procalcitonin (PCT) and C-reactive protein (CRP) in the early diagnosis of anastomotic leak (AL) in patients undergoing colorectal surgery.

Method: Diagnostic test in a tertiary care hospital. Patients who did not have preoperative measurements of PCT and CRP were excluded. Those with postoperative infection not related to AL were eliminated. The diagnostic efficacy measures were sensitivity (Sn), specificity (Sp), positive (PPV) and negative (NPV) predictive values, positive (LR+) and negative (LR-) likelihood ratios, and area under the receiver operating characteristic curve (AUROC).

Results: Thirty-nine patients were analyzed; six had AL (15.4%). PCT and CRP increased on the second postoperative day, only in patients with AL. The cut-off points at the second postoperative day were 1.55 ng/mL for PCT and 11.25 mg/L for CRP. The most efficacious test was PCR at second postoperative day (AUROC: 1.00; Sn: 100%; Sp: 96.7%; PPV: 85.7%; NPV: 100%; LR+: 33.0).

Conclusions: CRP at second postoperative day was the most effective test in the early diagnosis of AL in patients undergoing colorectal surgery, with a cut-off point lower than that reported in the international literature.