验证降钙素原（PCT）与C反应蛋白（CRP）可否作为吻合口瘘（AL）早期预测指标，并确定最佳临界值，为结直肠癌术后AL的早期识别提供帮助。

收集2013年1月至2017年4月鞍钢集团总医院收治的408例结直肠癌手术患者为研究对象，于术后第3、5天检测PCT、CRP质量浓度及白细胞计数（WBC），记录患者手术方式、术后出现AL及其他并发症，比较术后第3、5天AL组与非瘘并发症组、无并发症组的PCT、CRP、WBC水平差异。根据ROC曲线比较PCT、CRP、WBC对AL的预测准确性，并计算其敏感度、特异度、联合敏感度、联合特异度、阴性预测值、阳性预测值及最佳临界值。

19例出现AL，术后第3、5天AL组的PCT、CRP值均高于非瘘并发症组及无并发症组（P<0.05），术后第3天PCT、CRP的ROC曲线AUC分别为0.773、0.839，术后第5天PCT、CRP的ROC曲线AUC分别为0.893、0.863。第5天PCT、CRP预测AL的准确性均优于第3天。术后第5天PCT最佳临界值为2.15 μg/L，AL阴性预测值为96.4%，阳性预测值为32.1%，敏感度为84.2%，特异度为90.7%。术后第5天CRP最佳临界值为129.5 mg/L，AL阴性预测值为95.7%，阳性预测值为19.6%，敏感度为94.7%，特异度为77.6%。联合术后第5天PCT和CRP预测AL的敏感度和特异度分别为100.0%、70.4%。

PCT和CRP是结直肠癌手术后早期诊断AL的有价值的指标，术后第5天联合检测PCT和CRP更加有助于AL预测。

To verify whether procalcitonin (PCT) and C-reactive protein (CRP) can be used as an early predictor of anastomotic leakage (AL) and determine the optimal cut-off value, so as to provide evidence for early identification of AL after colorectal cancer surgery.

From January 2013 to April 2017, four hundred and eight cases undergoing colorectal cancer operation in Anshan Iron and Steel Group General Hospital were selected. The concentration of PCT, CRP and the white cell count (WBC) were detected 3, 5 d after operation (POD). The methods of operation, AL and other complications after operation were recorded. The differences of PCT, CRP and WBC levels among the AL group, the non-AL group and the non-complication group were compared on 3rd, 5th POD. According to the ROC curve, the prediction accuracy of PCT, CRP and WBC for AL were compared, and their sensitivity (SE), specificity (SP), joint sensitivity, joint specificity, negative predictive value (NPV), positive predictive value (PPV), the best critical value were also calculated.

AL occurred in 19 cases, and the PCT and CRP values of the AL group were higher than the other two groups (P<0.05). The AUC of PCT and CRP was 0.773 and 0.839 on 3rd POD, and 0.893 and 0.863 on 5th POD, respectively. The prediction accuracy of the 5th POD was better than that of the 3rd POD for AL. The optimal cut-off value of PCT on 5th POD was 2.15 g/L, and NPV, PPV, SE, and SP of AL were 96.4%, 32.1%, 84.2% and 90.7%, respectively. The optimal cut-off value of CRP on 5th POD was 129.5 mg/L, NPV, PPV, SE, and SP of AL were 95.7%, 19.6%, 94.7% and 77.6%, respectively. A joint-detection of PCT and CRP could provide higher SE and SP up to 100.0% and 70.4%, respectively.

PCT and CRP are valuable indicators for early diagnosis of AL after colorectal surgery. Combined detection of PCT and CRP on 5th POD may be more conducive to the prediction of AL.