Blockages develop when diseased tissue scars and thickens until food can't pass through it. One procedure, strictureplasty, widens the narrowed bowel. Another procedure, resection, involves removing the diseased intestine and joining the separated healthy sections. After surgery for Crohn's disease, the disease may be inactive for some time, but it may manifest itself again in another part of the gastrointestinal tract. Surgery is less common in ulcerative colitis than in Crohn's disease.
Emergency surgery is required for toxic megacolon or in cases of extensive bleeding.
People who have ulcerative colitis may have surgery to remove the colon, but this is considered only when medication no longer helps, or when the colon becomes cancerous or pre-cancerous. Surgery completely eliminates ulcerative colitis, but waste is no longer stored or expelled in the usual way. The standard procedure is the conventional end ileostomy. Once performed it means the person cannot control elimination, and must wear an external appliance, or bag, to collect waste. The end of the ileum is attached to the anus, allowing normal bowel movements.