Study on joint detection of serological markers in the diagnosis of Crohn's disease

Abstract

Objective To explore the values of detecting anti-Saccharomyces cerevisiae antibody (ASCA) IgA,ASCA IgG,anti laminaribioside carbohydrate antibody (ALCA),anti-chitobioside carbohydrate antibody (ACCA) and anti mannobioside carbohydrate antibody (AMCA) and antibody against outer membrane porin C of Escherichia coli (anti-OmpC) in the diagnosis of Crohn's disease (CD).Methods From October 10th 2012 to January 24th 2013,63 patients diagnosed as CD were selected.At the same period 30 patients diagnosed as ulcerative colitis (UC) were set as disease control group and 25 individuals without abnormal findings under endoscope and imaging examination were set as healthy control group.Fasting blood of all the subjects were drawn in the morning and serum was isolated after centrifuge.The level of ASCA IgG,ALCA,AMCA,ACCA,ASCA IgA,anti OmpC and I2 was detected by indirect enzyme linked immunosorbent assay.The sensitivity,specificity,positive predictive value and negative predictive value of each antibody were calculated and its value in the diagnosis was evaluated by receiver operating characteristic (ROC) curve.Results In the differential diagnosis of CD and UC by single antibody test,the accuracy of AMCA was the highest and the area under ROC curve was 0.739.In the screening of CD with single antibody examination,the diagnosis accuracy of I2 antibody was the highest and the area under ROC curve was 0.751.In multi antibodies joint examination,the accuracy of either ASCA IgA or AMCA positive was the highest in the differential diagnosis of CD and UC,also in the screening of CD and the area under ROC curve was 0.612 and 0.633,respectively.Conclusion In clinical practice,CD screening and the differential diagnosis of CD and UC may be achieved through detecting AMCA,ASCA IgA and I2 antibody. Key words: Crohn disease; Antibodies; Enzyme-linked immunosorbent assay; Serological markers; Diagnosis