ROC曲线评估血小板参数对移植肾功能恢复延迟的预测价值

ROC curve-based evaluation of platelet parameters for predicting delayed renal graft function

目的探讨血小板五项参数对移植肾功能恢复延迟（DGF）临床结局的预测价值。方法对本中心330例肾移植术后患者的临床资料进行回顾性分析,其中DGF47例（DGF组）,未发生DGF283例（非DGF组）,采用ROC曲线对肾移植术后受者外周血小板数量（PLT）、大型血小板比值（P-LCR）、血小板平均容积（MPV）、血小板分布宽度（PDW）、血小板压积（PCT）评估分析。结果术前DGF组血小板五项参数水平与非DGF组比较无明显差异。但在DGF诊断日,两组血小板参数相比具有显著的统计学差异（P〈0.05）。其中,DGF组PLT和PCT指标显著低于非DGF组（P〈0.05,P〈0.02）,而P-LCR、MPV、PDW指标则明显高于非DGF组（P=0.01,P〈0.01,P=0.036）。P-LCR、PDW和MPV的AUC分别为0.611±0.047,0.603±0.048和0.762±0.037,均显著大于机会参考下面积（P〈0.05）,最佳临界值分别为34.80%、12.95fl和11.55fl,其中,MPV的敏感度、特异度和youden指数均处于较高水平。PDW与P-LCR指标的敏感度较高,但特异性较低,两者对预测DGF的发生有一定的参考价值,但MPV预测DGF发生的价值更好,可作为诊断DGF发生的一种参考指标。PLT与PCT的AUC为0.37和0.38,对DGF无明显的预测价值。结论DGF发生时,血小板五项参数同未发生DGF的对照组比较有显著的差异,对肾移植术后早期受者MPV、PDW、P-LCR指标变化的监测,有助于早期诊断并及早治疗DGF,血小板参数MPV预测DGF的临床价值达到中度（0.7~0.9）,MPV〉11.55fl时,需警惕患者有发生DGF的风险。

Objective To investigate the value of evaluating 5 platelet parameters in predicting delayed graft function（DGF） in patients following kidney transplantation. Methods We retrospectively analyzed the pre- and postoperative（within 2 months）data of 330 renal transplant recipients. The cases with DGF and those without were analyzed to assess the association between relationship between DGF following transplantation and the variations of blood platelet parameters including platelet count（PLT）, large platelet ratio（P- LCR）, mean platelet volume（MPV）, platelet volume distribution width（PDW） and platelet hematocrit（PCT）. Results The DGF and non-DGF cases were comparable for the platelet parameters before the operation. On postoperative day 7 when the diagnosis of DGF was made, PLT（P〈0.05） and PCT（P〈0.02） were significantly lower while MPV（P〈0.01）, PDW（P=0.036） and P-LCR（P=0.01） significantly higher in DGF group than in non-DGF group. The AUCs of P-LCR（0.611±0.047）, PDW（0.603±0.048） and MPV（0.762±0.037） were significantly higher than the reference area（P〈0.05） with cut-off values of 34.80%, 12.95 fl and 11.55 fl, respectively. MPV showed a high sensitivity, specificity and Youden index for predicting DFG; PDW and P-LCR had a high sensitivity but a low specificity for predicting DFG with a modest diagnostic value. PLT and PCT, with AUCs of were 0.37 and 0.38, respectively, did not have a predictive value for DGF. Conclusions Significant variations in platelet parameters occur in the event of DGF in renal transplant recipients, and monitoring the postoperative changes in MPV, PDW, and P- LCR can help in early diagnosis and treatment of DGF. MPV has a moderate value（0.7- 0.9） in predicting DGF, and a MPV11.55 fl suggests the risk of DGF.