纤维蛋白(原)降解产物与D-二聚体最适比例可信区间的探讨

The confidence interval of optimal ratio between the fibrin degradation products and D-dimer

目的探讨纤维蛋白(原)降解产物(FDP)与D-二聚体(D-D)最适比例可信区间,以发现干扰FDP和(或)D-D检测的潜在影响因素。方法回顾性分析该院2019年1月至2020年12月凝血七项检测结果中FDP和D-D均在其线性范围内(FDP:2.5~80μg/mL;D-D:0.16~5.16μg/mL FEU)的报告共206879份,作为探索FDP/D-D最适比例可信区间的建立组,根据D-D水平分为以下3个组别:<0.5μg/mL FEU组、0.5~<2.5μg/mL FEU组和≥2.5μg/mL FEU组,建立3个组别FDP/D-D最适比例可信区间。选取该院2021年3月进行FDP和D-D检测的样本1022例,作为最适比例可信区间验证组,通过稀释法和更换验证试剂法来定义验证数据中的阳性样本和阴性样本,采用效能指标(灵敏度、特异度、阳性预测值、阴性预测值)评价该可信区间在验证数据中发现阳性样本和阴性样本的能力。结果当D-D<0.5μg/mL FEU时,FDP/D-D的最适比例可信区间为10.40~40.00;当D-D为0.5~<2.5μg/mL FEU时,FDP/D-D的最适比例可信区间为1.82~7.25;当D-D≥2.5μg/mL FEU时,FDP/D-D的最适比例可信区间为1.47~3.94。验证组中位于线性范围以内的样本共767例,根据各组别FDP/D-D可信区间进行判断,3个组中分别有60.00%(3/5)、4.37%(25/572)和8.95%(17/190)样本FDP/D-D异常,其中分别有100.00%(3/3)、24.00%(6/25)和29.41%(5/17)样本为阳性样本。线性范围以内数据总体灵敏度为73.68%(14/19),特异度为95.86%(717/748),阳性预测值为31.11%(14/45),阴性预测值为99.31%(717/722)。验证组中有255例样本超过检测范围,根据D-D≥2.5μg/mL FEU时的FDP/D-D最适比例可信区间,该群样本中有26.27%(67/255)样本FDP/D-D异常,异常的样本中有83.58%(56/67)的阳性样本,16.42%(11/67)阴性样本;对于线性范围以外的结果即使FDP/D-D正常,仍有35.11%(66/188)的阳性样本漏检。结论联合检测FDP和D-D,同时结合FDP/D-D更有利于辨别两者检测结果的准确性。

Objective To explore the optimal ratio between fibrin degradation product(FDP)and D-dimer(D-D),and to find the potential factors that may affect the detection of FDP and(or)D-D detection.Methods We collected 206879 historical data as the establishment group to explore the optimal proportion of FDP/D-D confidence interval,from January 2019 to December 2020 in West China Hospital of Sichuan University,which included seven coagulation tests and FDP and D-D were all within the linear range(FDP:2.5-80μg/mL;D-D:0.16-5.16μg/mL FEU).According to D-D level,the data of establishment group were divided into the following three groups:<0.5μg/mL FEU group,0.5-<2.5μg/mL FEU group and≥2.5μg/mL FEU group.FDP/D-D optimal ratio confidence intervals(CI)were established for three groups respectively.We selected 1022 samples which detected FDP and D-D simultaneously from West China Hospital of Sichuan University in March 2021 as the optimal ratio CI validation group.Positive and negative samples in the validation data were defined by the method of dilution and the method of change of validation reagent.Then we evaluated the ability of the confidence interval to detect positive and negative samples in validation data by efficacy indicators(sensitivity,specificity,positive predictive value,negative predictive value).Results When D-D<0.5μg/mL FEU,the optimal ratio CI of FDP/D-D was 10.40-40.00.When D-D was 0.5-<2.5μg/mL FEU,the optimal ratio CI of FDP/D-D was 1.82-7.25.When D-D was≥2.5μg/mL FEU,the optimal ratio CI of FDP/D-D was 1.47-3.94.There were 767 samples within the linear range in the validation group.According to the FDP/D-D CI of each group,there were 60.00%(3/5),4.37%(25/572)and 8.95%(17/190)samples with abnormal ratio in the three groups,and there were 100.00%(3/3),24.00%(6/25)and 29.41%(5/17)samples were positive,respectively.The overall sensitivity of the samples within linear range was 73.68%(14/19),specificity was 95.86%(717/748),positive predictive value was 31.11%(14/45),negative predictive value was 99.31%(717/722).There were 255 samples in the validation group that exceeded the linear range,according to optimal ratio CI of D-D≥2.5μg/mL FEU,there were 26.27%(67/255)samples with abnormal ratio,among which there were 83.58%(56/67)positive samples and 16.42%(11/67)negative samples.For the samples outside the linear range,35.11%(66/188)of positive samples were missed even though the FDP/D-D was normal.Conclusion Combined detection of FDP and D-D,then bond of FDP/D-D are more conducive to distinguish the accuracy of the detection results.