活化部分凝血活酶时间检测狼疮抗凝物的灵敏度及其相关性

Sensitivity and correlation of activated partial thromboplastin time to lupus anticoagulants

目的评估常规活化部分凝血活酶时间(APTT)对改良的稀释蝰蛇毒时间(DRVVT)法及硅凝固时间(SCT)法检测狼疮抗凝物(LA)的灵敏度及相关性。方法回顾性分析2018年12月至2020年9月于我院检测LA阳性且同时检测了APTT的386例样本的检测结果。根据APTT参考区间上限分为APTT正常组(APTT≤43.0 s)和APTT异常组(APTT>43.0 s)。2组数据非正态分布以M(P25~P75)表示,组间数据比较采用非参数检验,采用受试者工作特征(ROC)曲线分析LA预测APTT异常时的临界值和灵敏度,采用Spearman秩相关分析APTT与LA的相关性。结果386例LA阳性样本中,APTT正常177例(45.9%),APTT异常209例(54.1%)。APTT异常组的DRVVT标准化比值(NR)及SCT-NR显著高于APTT正常组(P<0.01)。APTT对LA的灵敏度:DRVVT-NR、SCT-NR分别为1.39和1.83。APTT与DRVVT-NR、SCT-NR的相关系数分别为0.702(P<0.01)和0.641(P<0.01)。结论LA阳性样本的APTT未必延长,其结果由APTT对LA的灵敏度决定。了解实验室APTT对LA的灵敏度及其相关性,正确解释APTT与LA结果之间的关系,具有实际临床应用价值。

Objective To evaluate the sensitivity and correlation of activated partial thromboplastin time(APTT)to diluted Russell’s viper venom time(DRVVT)and silica clotting time(SCT)in the detection of lupus anticoagulant(LA).Methods From December 2018 to September 2020,386 LA-positive patients were examined by APTT and analyzed retrospectively.The patients were divided into normal APTT(≤43.0 s)and abnormal APTT(>43.0 s)groups according to the upper limits of their APTT reference intervals.The non-normal distribution of two groups of data was expressed as the median M(P25-P75).The receiver operating characteristic curve was used to analyze the effectiveness of LA in predicting abnormal APTT as well as the sensitivity of APTT in the detection of LA.Spearman’s correlation analysis was used to analyze the correlation between APTT and LA in the two groups.Results In total,177(45.9%)cases showed normal APTT and 209(54.1%)cases showed abnormal APTT.The normalized ratios(NRs)of DRVVT and SCT in the abnormal APTT group were significantly higher than those in the normal APTT group(P<0.01).The NRs of DRVVT and SCT to LA detection were 1.39 and 1.83,respectively.The correlation coefficients of APTT with the DRVVT-NR and SCT-NR were 0.702(P<0.01)and 0.641(P<0.01),respectively.Conclusion The APTT of LA-positive samples may not necessarily be prolonged.This is determined by the sensitivity of the APTT to LA.Elucidating the sensitivity and correlation of the laboratory APTT to LA and correctly interpreting the relationship between the APTT and LA results have practical clinical value.