P-ANCA and ASCA role in the inflammatory bowel disease diagnosis

Objective: The term ?inflammatory bowel diseases (IBD)? is being used to define chronical bowel diseases of poorly understood etiology with activations and remissions. The well recognised two major forms are ulcerative colitis (UC) and Crohn?s disease (CD). A less common form of IBD is indeterminate colitis. Correct diagnosis of inflammatory bowel disease (IBD), especially the differentiation between Crohn's disease (CD) and ulcerative colitis (UC), is highly important toward treatment and prognosis. Serological markers are non-invasive diagnostic tools that could be of value in differentiating CD from UC, in cases of indeterminate colitis, and in the identification of subgroups in IBD. The aim of this study was to evaluate the diagnostic accuracy of perinuclear antineutrophilcytoplasmic (p-ANCA) and anti-Saccharomyces cerevisiae antibodies (ASCA) for IBD.Material and Method: We studied sera from 28 with Crohn's disease (CD), 37 with ulcerative colitis (UC), and 24 healthy controls. Clinical data, disease activity, and disease diagnosis were gathered at the time of serum sampling. Enzyme-linked immunosorbent assay was utilized to determine titers of antibodies to ASCA and pANCA the presence of perinuclear staining for ANCA was confirmed by immunofluorescence.Results: Mean age of the patients with UC 41,95±12,6, with CD 39,61±11,3 and the healthy controls 39,67±7,9 respectively. p-ANCA were found in 10 of 37 patients with ulcerative colitis (sensitivity % 27, specificity % 100, p= 0,006), 2 of 28 patients with Crohn's disease (sensitivity % 7,1, specificity % 100, p= 0,493), and none of 24 healthy controls. ASCA were found in 22 of 28 patients with CD (sensitivity % 78,6, specificity % 95,8, p< 0,001), 12 of 37 patients with UC (sensitivity % 32,4, specificity % 95,8,p= 0,01), and 1 of 24 healthy controls (% 4,17). In conclusion, there was no correlation between p-ANCA and the localization or extent of the inflammatory bowel disease.Conclusion: Both serologic tests may aid in the differential diagnosis ofinflammatory bowel disease. This must be considered in view of the invasive nature of the?gold standard? tests, rendering the potential benefit of a good serological test in this population great.Key words: Ulcerative colitis, Crohn?s diesase, p-ANCA, ASCA.