ABSTRACT
Objective To evaluate the clinical significance of combined measurement of antiperinuclear neutrophil cytoplasmic antibody(ANCA)and anti-saccharomyees cerevisia antibody(ASCA)for the diagnosis of inflammatory bowel disease(IBD)patients and difierentiation of Crohn's disease(CD)with ulcerative colitis(UC).Methods A total of 159 patients with IBD(97 UC,62 CD),167 patients with other non-IBD gastrointestinal conditions(NIBDC)and 25 healthy controls(HC)were recruited in our research.ASCA and ANCA were detected by enzyme-linked immunosorbent assay(ELISA)and indirect immunofluorescence assay.respectively.Results The prevalence of ASCA-IsA or IgG in CD group,UC group,NIBDC and HC were43.5%,14.4%,29.3%and 0,respectively.The prevalence of ASCA-IgA or IgG in CD group were higher than those in other groups(X2=16.76 or 4.12,P＜0.01 or＜0.05).The prevalence of ANCA in CD group.UC group,NIBDC and HC were 8.1%,56.7%,4.8%and 0,respectively.The prevalence of AMA in UC group were much higher than those in other groups(X2=38.08 or 90.47,P＜0.01).The sensitivity specificity and positive predictive value(PPV)in ASCA+/ANCA-were 40.3%.93.8% and 80.6%,respectively,and in ANCA+/ASCA-were 48.5%,98.4% and 97.9%,respectively.Condusions ASCA or ANCA testing alone are not sensitive enoulgh for diagnosing CD and UC,but their combination asses are specific for differential diagnosis between CD and UC.Combined testing of ASCA-IgA with IgG can improve the sensitivity in screening CD patients.The ASCA positive pattern in Chinese CD group are correlated with surgery.