免疫荧光层析法检测新型冠状病毒IgM/IgG抗体的临床价值及假阳性分析

The Clinical Value of 2019-nCov IgM and IgG Tests by Immunofluorescence Chromatography and the Analysis of Its False Positive Results

目的探讨新型冠状病毒(SARS-CoV-2)抗体在新型冠状病毒肺炎(COIVD-2019)患者和非COIVD-2019患者中的检测效果。方法选取161例COIVD-2019患者和79例非COIVD-2019[合并人类免疫缺陷病毒(HIV)感染、结核和自身免疫性疾病]患者,采用免疫荧光层析法对患者的血清标本进行SARS-CoV-2 IgM和IgG抗体检测。结果161例COIVD-2019患者SARS-CoV-2 IgM和IgG抗体阳率分别是88.82%(143/161)和93.79%(151/161)。79例非COIVD-2019患者SARS-CoV-2 IgM和IgG抗体阳性率分别为16.46%(13/79)和7.59%(6/79)。免疫荧光层析法与化学发光分析法进行一致性评价,IgM抗体一致率达84.91%(135/159),IgG一致率达88.68%(141/159),两种方法检测IgG结果的一致性比IgM偏高。检测HIV、结核、系统性红斑狼疮、类风湿性关节炎(RA)和自身免疫性肝炎(HIA)患者血清出现不同程度假阳性,稀释假阳性标本后检测6例RA、2例结核和1例HIA患者SARS-CoV-2抗体转阴。结论免疫荧光层析法性能满足COIVD-2019临床辅助诊断和流行病学调查,但应注意与流行病不相符的检测结果。通过稀释血清标本,可以一定程度降低检测过程中假阳性,对COIVD-2019患者发病早期标本检测灵敏度的影响需进一步研究。

Objective To investigate the detection efficacy of SARS-CoV-2 antibody in COIVD-2019 patients and non-COIVD-2019 patients.Methods Serum antibodies(IgM/IgG)against SARS-CoV-2 were detected by immunofluorescence chromatography in 161 patients with COIVD-2019,68 healthy controls and 79 non-COIVD-2019 patients(complicated with HIV,tuberculosis and autoimmune diseases).Results The positive rates of SARS-CoV-2-specific IgM and IgG in 161 patients with COIVD-2019 were 88.82%(143/161)and 93.79%(151/161),respectively.The positive rates of SARS-CoV-2-specific IgM and IgG in 79 non-COIVD-2019 patients were 16.46%(13/79)and 7.59%(6/79),respectively.Among these results,both SARS-CoV-2-specific IgM and IgG were positive in 5 cases.The consistency of immunofluorescence chromatography and chemiluminescence analyses showed that the consistency rate of IgM antibody was 84.91%(135/159)and was 88.68%for IgG(141/159).The consistency of IgG results was higher than that of IgM in both methods.Detections of HIV,tuberculosis,SLE,RA and serum of patients with autoimmune hepatitis showed false positive results in different degrees.After dilution of false positive samples,SARS-CoV-2 antibodies in 6 patients with RA,2 patients with tuberculosis and 1 patient with HIA turned to negative.Conclusion The performance of immunofluorescence chromatography could meet the standards of clinical diagnosis and epidemiological investigation of COIVD-2019.However,attentions should be paid to the detection results which are not consistent with the epidemic.Dilutions of serum samples could be partially helpful for reducing the false positive results of SARS-CoV-2 antibodies in the detection process.The effect of dilution on the detection sensitivity of early COVID19 needs a further study.