凝血相关检测常见干扰因素分析与探讨

Analysis and discussion of common interfering factors in coagulation related test

目的:探讨当D-二聚体(D-D)检测出现假阴性与假阳性结果,且内源性凝血因子Ⅷ、Ⅸ、Ⅺ、Ⅻ活性出现假性减低时,是否需要用稀释法排除干扰。方法:选取医院2020年10月—2021年10月门诊与住院病例155例,将其分为3组。其中D-D假阴性组样本100例:收集D-D>5 mg/L,纤维蛋白(原)降解产物(FDP)>20μg/mL;D-D假阳性组50例;狼疮抗凝物(LAC)阳性组5例,且内源性凝血因子Ⅷ、Ⅸ、Ⅺ、Ⅻ活性测定假性减低。将各组相关指标分别进行各梯度稀释检测。结果:D-D假阴性组:D-D稀释检测前后结果比较,差异有统计学意义(P<0.05);D-D假阳性组:D-D稀释检测前后结果比较,差异有统计学意义(P<0.05);LAC阳性组:将5例LAC阳性患者的凝血因子活性进行不同稀释度检测,发现随着稀释倍数的增加,内源性Ⅷ、Ⅸ、Ⅺ、Ⅻ活性随之升高明显且最终会恢复至大概正常的水平。结论:当D-D出现假阴性时,可用稀释法使其暴露更多的抗原表位,以确保高浓度D-D结果检测的准确性;当D-D出现假阳性时,可通过稀释法降低干扰物质的浓度来获得更加准确的结果;LAC可对内源性凝血因子活性检测造成干扰,稀释法可得到更加准确的凝血因子活性。

Objective To investigate whether dilution method should be used to eliminate interference when false negative or false positive results of D-D assay and false decrease of the activity of endogenous coagulation factors(F) Ⅷ, Ⅸ, ⅪandⅫ occurred.Methods The outpatient and inpatient cases from October 2020 to October 2021 were selected and divided into three groups. D-D>5 mg/L, fibrin degradation product(FDP)>20 μg/mL, 100 cases of D-D false negative group;50 cases of D-D false positive group were collected. There were 5 patients with reduced pseudocoagulants with positive Lupus anticoagulants(LAC) and activity of endogenous coagulation factors(F) Ⅷ, Ⅸ, Ⅺ and Ⅻ. The results were detected by gradient dilution.Results D-D false negative group: The results were compared before and after D-D dilution test, and the difference was statistically significant(P < 0.05);D-D false positive group: The results were compared before and after D-D dilution test, and the difference was statistically significant(P < 0.05);Pseudodecreased endogenous coagulation factor activity group: The activity of coagulation factors in 5 LAC positive patients was detected by different dilutions, and it was found that with the increase of dilutions, the activity of endogenous coagulation factors Ⅷ, Ⅸ, Ⅺ and Ⅻ increased significantly and eventually recovered to about normal levels.Conclusion When D-D was false negative, more epitopes of D-D could be exposed by dilution method to ensure the accuracy of detection of high concentration D-D. When D-D was false positive, the concentration of interfering substances could be reduced by dilution method to obtain more accurate results. LAC might interfere with the determination of endogenous clotting factor activity. Dilution method could obtain more accurate detection level of clotting factor activity.