肺炎支原体IgG类抗体亲和力检测的实验研究与临床应用

目的探讨肺炎支原体IgG类抗体亲和力检测在肺炎支原体感染诊断中的意义。方法用被动颗粒凝集试验(PPA)和间接免疫荧光法(IFA)检测儿童上呼吸道感染者血清IgM类抗体水平,同时用IFA法检测其IgG类抗体的亲和力,并对检测结果进行相关性分析和一致性检验。结果在IgM类抗体检测上PPA法检出阳性率(60/120)高于IFA法(49/120),两法检测结果缺乏一致性。而IFA法检测IgG类抗体阳性的97例中,有22例检出低亲和力IgG类抗体,其中20例同时检出IgM类抗体,两法检测结果具有显著的相关性(P<0.001)和较好的一致性(0.7>Kappa>0.4)。结论肺炎支原体低亲和力IgG类抗体检测有与IgM类抗体检测类似的早期诊断价值,可与IgM类抗体联合检测用于区分近期感染、感染后复发或再次感染。

Experimental study and clinical applications of Mycoplasma pneumoniae IgG avidity detection

Objective To explore the significance of Mycoplasma pneumoniae IgG avidity detection for early diagnosis of Myeoplasma pneumoniae infection. Method Mycoplasma pneurnoniae IgM levels of children＇s with upper respiratory tract infections were detected with Passive particles Agglutinate Experiment （PPA） and Indirect lmmunofluorescence Assay （IFA）. Meanwhile, the IgG avidity was detected with the modified IFA method, and correlation analysis and consistency checking of the results were performed. Result For IgM antibody detection, the positive rate by PPA （60/120） was higher than that by IFA （49/120）, whereas the results of PPA and IFA were inconsistent. In the 97 positive cases of Mycoplasma pneumoniae IFA IgG, 22 cases were detected as low avidity IgG antibodies, 20 cases of which were IgM antibody positive. The results of both methods showed significant correlation （ P 〈 0.001 ） and moderate consistency （ 0.7 〉 Kappa 〉 0.4）. Conclusion Mycoplasma pneumoniae low avidity IgG antibody detection has similar early diagnosis value with IgM antibody detection, and can be combined with the detection of low avidity IgM to distinguish early infection, recurrent infection or re-infection.