ABSTRACT
Background: There is no gold standard for the diagnosis and monitoring of inflammatory bowel disease (IBD).As immune system plays crucial role in the pathogenesis of IBD,some immune-specific serum antibodies are considered to be useful tools for the diagnosis and differential diagnosis of the disease.Aims: To investigate the clinical significance of serum antibodies,including anti-Saccharomyces cerevisiae antibody (ASCA) and perinuclear anti-neutrophil cytoplasmic antibody (pANCA) in IBD.Methods: Serum samples were obtained from 91 consecutive IBD patients from Feb.2015 to May 2016 at the First Affiliated Hospital of Soochow University.Of them,52 were Crohn's disease (CD) and 39 were ulcerative colitis (UC).Serum samples of 36 non-IBD patients were served as controls.ASCA-IgG and ASCA-IgA were detected by ELISA,and pANCA by indirect immunofluorescence assay.Using clinical diagnosis as gold standard,crosstabs statistics was performed to measure the diagnostic accuracy of ASCA and pANCA,and ROC curve,Pearson Chi-square test and Fisher's exact test were employed for analyzing the correlations of these two serum antibodies with IBD,CD,UC,and the location of the disease.Results: Both serum ASCA-IgG and IgA were correlated with CD (AUC=0.626 and 0.614),while UC was correlated with ASCA-IgA only (AUC=0.486).Serum pANCA had relevance to IBD (r=0.342),CD (r=-0.262) and UC (r=0.614);its sensitivity and specificity for IBD and UC were superior to those for CD (P＜0.05).In CD patients,ASCA-IgG was associated with terminal ileal disease (P＜0.05),and pANCA was associated with colonic involvement (P＜0.05).In UC patients,both ASCA-IgG and IgA were correlated with terminal ileal disease (P＜0.05).Conclusions: Serum ASCA and pANCA may be helpful for discrimination between CD and UC when the diagnosis of IBD is established.Furthermore,they are closely associated with the disease location,ASCA is related with the terminal ileal disease and pANCA is related with colonic involvement.
ABSTRACT
Anti-glomerular basement membrane antibody (anti-GBM Ab) disease is characterized by circulating antibodies to the glomerular basement membrane and the deposition of IgG or, rarely, IgA along the glomerular basement membrane. This disease accounts for 10-20% of crescentic glomerulonephritis. We report two patients with anti-GBM Ab disease who were positive for perinuclear-anti-neutrophil cytoplasmic antibody (p-ANCA). Percutaneous renal biopsies showed many crescent formations and linear deposits of IgG along the glomerular basement membrane. Serologic tests for p-ANCA were positive. They were treated with steroid pulse and cyclophosphamide and one patient also underwent plasma exchange therapy. Despite immunosuppressive therapy, their renal functions did not improve and both required regular hemodialysis.