Diagnostic Criteria and Clinical Characteristics
Diagnostic Criteria for IBD
Diagnostic evaluation should include
Stool studies including fecal leukocytes, culture for appropriate bacterial and parasitic cultures, assays for C difficile toxin, appropriate tests for possible viral etiologies (cytomegalovirus) and Mycobacterium tuberculosis.
Colonoscopy with biopsy and ileum cannulation. Granulomas are present on endoscopic biopsies in approximately 10% of CD, crypt abscesses are indicative of UC.
Serologic markers may be helpful; anti-Saccharomyces cerevisiae antibodies (ASCA) and antineutrophil cytoplasmic antibodies with perinuclear staining (p-ANCA) have high sensitivity for IBD in combination compared to other causes of intestinal inflammation, but sensitivity varies for different ethnic groups (much lower, eg, in regions endemic for tuberculosis). ASCA shows high specificity for CD, and p-ANCA for UC, although patients with CD limited to the colon may be positive ...