原发性血小板减少性紫癜两种血小板相关抗体检测方法的比较

目的运用流式细胞术(FCM)和酶联免疫竞争抑制法(ELISA)检测血小板相关抗体(PAIgG、PAIgA、PAIg M),研究其在原发性血小板减少性紫癜(ITP)诊断中的应用价值。方法应用FCM和ELISA检测19例ITP患者血小板膜表面(直接法)及血浆中(间接法)的血小板相关抗体及17例健康自愿者血小板膜表面的相关抗体,比较各指标与正常对照组之间的表达差异,并对结果进行诊断价值的评价。结果FCM和ELISA检测ITP患者血小板相关抗体的结果均明显高于正常对照组(P<0.01),其中ITP组PAIgG较对照组明显升高;FCM测得的阳性率(84%)比ELISA法(79%)稍高,两种方法差异无统计学意义(P>0.05);直接法和间接法差异也无统计学意义(P>0.05)。结论血小板相关抗体(尤其是PAIgG)有助于诊断ITP;其中FCM是血小板相关抗体检测的一项快速、灵敏、简便的方法,而ELISA是最常用的定量试验方法,可动态观察病情变化;两种方法同时应用具有较大的临床推广价值。

Evaluation of two methods in detection of platelet-associated autoantibody for the diagnosis of idiopathic thrombocytopenic purpura

Objective To evaluate the methods of measuring platelet-associated antibody PAIgG/ PAIgA/ PAIgM by flow cytometry(FCM) and enzyme linked immunosorbent assay(ELISA), and to investigate their diagnostic value for patients with idiopathic thrombocytopenic purpura(ITP).Methods With FCM and ELISA respectively, PAIg on the platelet membrane and in plasma were measured in 19 patients with ITP and 17 healthy volunteers, and were compared with each other in order to find out whether there were differences in these groups.Results FCM and ELISA measurement in patients with ITP were significantly higher than those in control group (P<0.01). However, there were no significant differences in values between the direct method and the indirect method(P>0.05). Compared with the results of ELISA, the positive percentage of PAIgG measured by FCM(84%) in ITP patients was slightly higher than that by ELISA(79%).Conclusion The platelet-associated antibodies of PAIgG/ PAIgA/ PAIgM, especially PAIgG,are important for diagnosing ITP. FCM, in combination with ELISA, may improve the reliability and the positive percentage of detection in ITP patients.