血浆热灭活处理在Nijmegen法检测遗传性凝血因子Ⅷ抑制物中的应用

Analysis of heat-treatment in detection of blood coagulation factor Ⅷ by Nijmegen-Bethesda assay

目的评价血浆样本热灭活处理在Nijmegen法检测遗传性凝血因子Ⅷ(FⅧ)抑制物中的应用价值。方法同时应用Nijmegen法及增加热灭活步骤的Nijmegen法检测52例中、重型血友病A(HA)患儿血浆中FⅧ抑制物滴度。以抑制物滴度≥0.60BU判为阳性结果,对两种方法检测结果的阳性率及抑制物滴度水平进行分析。结果两种方法的抑制物阳性率检测差异无统计学意义(P>0.05),但有2例中间型HA患儿的血浆用原方法检测为阴性但热灭活处理后检测为阳性。两种方法检测的抑制物滴度水平呈显著的正相关(r=0.990 8,P<0.000 1)。在两种方法检测均为抑制物阴性的患儿中,血浆热灭活处理组的抑制物滴度[0.37(0.17,0.48)BU]明显高于无热灭活处理组[0.12(0.02,0.34)BU],差异有统计学意义(P<0.01);而在抑制物阳性组,两种方法的检测结果差异无统计学意义(P>0.05)。结论待测血浆样本热灭活处理在Nijmegen法检测FⅧ抑制物检测中的结果可信,且检测前增加血浆热灭活处理步骤可提高检测的灵敏度。

Objective To evaluate the clinical value of heat treatment of plasma samples in blood coagula tion factor Ⅷ （F Ⅷ） inhibitory by Nijmegen-Bethesda assay. Methods Totally 52 samples simultaneous detec ted by Nijmegen-Bethesda assay and Nijmegen Bethesda assay with heat inactivation steps. Blood coagulation FⅧ inhibitor ≥0.60 BU in children with severe hemophilia A （HA） were positive. The positive rate and in hibitor titer level of the two methods was analyzed. Results The positive rates of inhibitors between the two methods was no statistically significant difference （P〉0.05）. However,in two intermediate HA patients, the non heated samples were negative but positive in heated samples. There was a significant correlation between the two methods （r=0. 990 8,P〈0. 000 1）. In children with both methods tested inh itor titer of the plasma heat inactivation treatment group [0. 37 （0. 17,0.48） BU] than that of the heat free inactivation treatment group [0.12（0. 02 ,0. 34）BU]. The d bitor negative,the inhib was significantly higher fference was statistically significant （P〈0.01）. While in the inhibitor positive group,the difference between the two methods was not statistically significant （P〉0. 05）. Conclusion The heat inactivation of the plasma samples to be tested is credible in the detection of F Ⅷ inhibitors by the Nijmegen- Bethesda method. Increasing the plasma heat inacti vation treatment step prior to detection increases the sensitivity of the assay.