ASGE guideline: Endoscopy in the diagnosis and treatment of inflammatory bowel disease

Colonoscopy with ileoscopy should be performed in the evaluation of IBD and for differentiating UC from CD (B). Mucosal biopsy specimens are important for the diagnosis of IBD and may help differentiate CD from UC (B). When colonoscopy is contraindicated, or the extent of disease is limited, flexible sigmoidoscopy may provide an adequate diagnosis (C). EGD or enteroscopy may be helpful for diagnosing IBD when other studies have negative results and for differentiating CD from UC in indeterminate colitis (B). CE is a less invasive technique for evaluating the small intestine for Crohn's involvement and has been shown to be more sensitive than radiologic and endoscopic procedures for detecting small bowel lesions (B). In patients with CD and known or suspected high-grade strictures, CE should not be performed (C). Small bowel follow-through or CT enterography should be obtained before CE in patients with CD to assess for high-grade strictures (C). CRC risk is increased in both UC and extensive Crohn's colitis and surveillance colonoscopy with multiple biopsies should be performed every 1 to 2 years beginning after 8 to 10 years of disease (B). The finding of dysplasia in flat mucosa, especially if multifocal, is an indication for total colectomy (B). Colectomy is indicated for colorectal cancer, high-grade dysplasia or low-grade dysplasia (particularly multifocal) in flat mucosa. A dysplastic mass lesion that cannot be removed endoscopically, or is associated with dysplasia elsewhere in the colon, is an indication for total colectomy (B). Dysplastic polypoid lesions may be managed as sporadic adenomas provided they are completely resected and there is no dysplasia in flat mucosa surrounding the polyp or elsewhere in the colon (B). EUS is highly accurate for characterizing perianal Crohn's disease (C). A colonic stricture in the setting of UC should be considered malignant until proven otherwise. If adequate evaluation cannot be performed, then colectomy is indicated (C). Chronic benign fibrotic strictures associated with obstructive symptoms may be managed with endoscopic balloon dilation with or without steroid injections (B).