Conditions that mimic inflammatory bowel disease. Diagnostic clues and potential pitfalls.

Many of the features that identify idiopathic inflammatory bowel disease are also found with other colorectal conditions that are often encountered by the primary care physician. Although, initially, symptoms of these disorders may appear to be caused by ulcerative colitis or Crohn's disease, the cause could be bacterial, viral, parasitic, or fungal infection. Ischemic colitis and radiation colitis are other conditions that are similar in presentation to ulcerative colitis. In most cases, the physician should be able to make a differential diagnosis from a thorough history and physical examination, anoscopy or sigmoidoscopy, rectal biopsy, stool examination, and serology. An occasional patient, in whom diagnosis is not made by these methods, may require a barium enema study, colonoscopy, or referral to a gastroenterologist.