核周型抗中性粒细胞胞质抗体和抗酿酒酵母抗体在炎症性肠病中的临床意义

Clinical Significance of Perinuclear Antineutrophil Cytoplasmic Antibodies and Anti-Saccharomyces cerevisiae Antibodies in Inflammatory Bowel Disease

背景:核周型抗中性粒细胞胞质抗体(pANCA)和抗酿酒酵母抗体(ASCA)是一组与炎症性肠病(IBD)密切相关的免疫球蛋白,但对溃疡性结肠炎(UC)、克罗恩病(CD)的诊断和鉴别诊断的价值仍有待进一步验证。目的:探讨pANCA和ASCA在UC与CD诊断和鉴别诊断中的意义。方法:以酶联免疫吸附测定(ELISA)检测64例UC、62例CD和56例健康对照者的血清pANCA、ASCA水平和阳性率,分析pANCA、ASCA及其组合的诊断敏感性、特异性、阳性预测值(PPV)和阴性预测值(NPV)。结果:UC组血清pANCA水平[(584.22±347.70)pg/ml对(304.99±211.10)pg/ml和(390.92±82.82)pg/ml,P<0.01]和阳性率(50.0%对14.5%和14.3%,P<0.01)显著高于CD组和健康对照组,三组间血清ASCA水平和阳性率无明显差异。pANCA^+和pANCA^+/ASCA-诊断UC的敏感性、特异性、PPV和NPV分别为50.0%、85.7%、80.0%、60.0%和42.2%、89.3%、81.8%、57.5%,ASCA^+和ASCA^+/pANCA^-诊断CD的敏感性、特异性、PPV和NPV分别为8.1%、87.5%、41.7%、46.2%和3.2%、91.1%、28.6%、45.9%。结论:pANCA阳性有利于UC的诊断。pANCA/ASCA联合检测有助于鉴别UC,但对CD诊断价值不高。

Background： Perinuclear antineutrophil cytoplasmic antibodies （pANCA） and anti-Saccharomyces cerevisiae antibodies （ASCA） are immunoglobulins closely related with inflammatory bowel disease （IBD）. The role of pANCA and ASCA in the diagnosis of ulcerative colitis （UC） and Crohn＇s disease （CD） remains further verification. Aims： To investigate the significance of pANCA and ASCA in the diagnosis and differential diagnosis of UC and CD. Methods： Serum samples were obtained from 64 patients with UC, 62 patients with CD and 56 healthy controls. Levels and positivity rates of pANCA and ASCA were determined by enzyme-linked immunosorbent assay （ELISA）. The sensitivity, specificity, positive predictive value （PPV） and negative predictive value （NPV） of pANCA, ASCA and their combination were analyzed. Results： Serum pANCA level was significantly higher in UC group than that in CD group and healthy controls [（584.22±347.70） pg/ml vs. （304.99±211.10） pg/ml and （390.92±82.82） pg/ml, P〈0.01], so was the positivity rate of pANCA （50.0% vs. 14.5% and 14.3%, P〈0.01）. The level and positivity rate of serum ASCA among these three groups had no significant difference. The sensitivity, specificity, PPV and NPV of pANCA^＋ and pANCA^＋/ASCA^- in diagnosis of UC were 50.0%, 85.7%, 80.0%, 60.0% and 42.2%, 89.3%, 81.8%, 57.5%, respectively, and those of ASCA^＋ and ASCA^＋/ pANCA^-in diagnosis ofCD were 8.1%, 87.5%, 41.7%, 46.2% and 3.2%, 91.1%, 28.6%, 45.9%, respectively. Conclusions： Positive pANCA favors the diagnosis of UC. Detection of pANCA together with ASCA is helpful for the differential diagnosis of UC, but is not of high value for the diagnosis of CD.