探讨国内抗酿酒酵母抗体（ASCA）鉴别诊断克罗恩病的截断点（cutoff值）的相关研究

目的检测抗酿酒酵母抗体IgG、IgA在克罗恩病患者中的表达水平,探讨其鉴别诊断克罗恩病的cutoff值。方法纳入2018年10月～2019年4月期间诊断为克罗恩病的患者109例,溃疡性结肠炎30例,内镜检查无异常者25例。间接酶联免疫检测法测定患者血清中抗酿酒酵母抗体IgG、IgA表达水平,计算其cutoff值、灵敏度、特异度等指标。结果抗酿酒酵母抗体的阳性率为47.71%,抗酿酒酵母抗体IgG的cutoff值为10.5,灵敏度为71.56%,特异度为61.82%;抗酿酒酵母抗体IgA的cutoff值为0.415,灵敏度为66.06%,特异度为78.18%;两者任一阳性的灵敏度为85.32%,两者均阳性的特异度为80.00%。结论抗酿酒酵母抗体IgG、IgA在中国人群克罗恩病患者中的表达水平不高,需制定相应的cutoff值,两者联合检测可提高克罗恩病患者检出率。

Study on the investigation on the cutoff value of domestic anti-Saccharomyces cerevisiae antibody (ASCA) for differential diagnosis of Crohn's disease

Objective To detect the expression level of anti-Saccharomyces cerevisiae antibody IgG and IgA in the patients with Crohn''s disease,and to explore the cutoff value of differential diagnosis of Crohn''s disease.Methods A total of 109 patients with Crohn''s disease,30 patients with ulcerative colitis and 25 patients with no abnormalities by endoscopy were enrolled from October 2018 to April 2019.Indirect enzyme-linked immunosorbent assay was used for the determination of ASCA IgG and IgA expression levels in patients'' serum,and the indicators such as cutoff value,sensitivity,and specificity were calculated.Results The positive rate of ASCA was 47.71%,the cutoff value of ASCA IgG was 10.5,the sensitivity was 71.56% and the specificity was 61.82%;the cutoff value of ASCA IgA was 0.415,the sensitivity was 66.06%,and the specificity was 78.18%;the sensitivity of either positive was 85.32%,and the specificity of both positive was 80.00%.Conclusion The expression levels of ASCA IgG and IgA are not high in the patients with Crohn''s disease in China.A corresponding cutoff value needs to be established,and the combined detection of the two can improve the detection rate of patients with Crohn''s disease.