Ulcerative colitis and Crohn's disease share the symptoms and clinical features of many diseases with infectious and non-infectious etiologies (e.g., appendicitis,diverticulitis, gonnorrhea) (1). Because there is no diagnostic gold standard for ulcerative colitis and Crohn's disease, a combination of clinical, laboratory, histopathologic, and radiographic parameters must be evaluated to appropriately identify IBD (1). However, even when a diagnosis of IBD has been determined, an established diagnosis of ulcerative colitis versus Crohn's Disease may remain unconfirmed in at least 10-15% of patients ("indeterminate colitis") (1).
In ulcerative colitis, inflammation is limited to the mucosa. In Crohn's disease, the entire intestinal wall is involved with inflammation (1). The typical manifestation of ulcerative colitis is bloody diarrhea (2). Abdominal pain, particularly in the lower abdomen or right lower quadrant, weight loss, and a fever generally accompany diarrhea in patients with Crohn's disease (3). The rectum is almost always involved in ulcerative colitis but rarely in Crohn's disease (4). Fistulae and perianal disease are common in Crohn's disease but not in ulcerative colitis (4).
Table 1: Clinical Characteristics of Crohn's Disease and Ulcerative Colitis
Differentiating Factors Between Crohn's Disease and Ulcerative Colitis (5-7)
| Crohn's Disease | Ulcerative Colitis | |
| Affected Area | Fairly common in the ileum and large intestine | Restricted to the colon |
| Endoscopic Features | Discontinuous distribution | Continuous distribution |
| Rectal sparing | Rectal involvement | |
| Cobblestone appearance | Granular appearance | |
| Deep irregular ulcerations | Microulcerations, shallow ulcerations | |
| Aphthous ulcers | ||
| Luminal narrowing | Rare luminal narrowing | |
| Friability fairly common | Friability very common | |
| Radiologic Features | Strictures or fistulae common | Strictures associated with malignancy |
| Deep fissures common | Fistulae not observed | |
| Deep fissures rare | ||
| Serologic Markers | Associated with ASCA | Associated with pANCA |
ASCA indicates anti-Saccharomyces cerevisiae antibody; pANCA, perinuclear antineutrophil cytoplasmic antibody (5).
Adapted from Schölmerich & Warren, Podolsky and D'Haens et al. (5-7)
- Friedman S, Blumberg RS. Inflammatory Bowel Disease. In: Harrison's Internal Medicine. McGraw-Hill Access Medicine. 2006. The McGraw-Hill Companies. Available at: http://www.accessmedicine.com/content.aspx?aID=90323.
- Travis S, Jewell DP. Ulcerative colitis: clinical presentation and diagnosis. In: Satsangi J, Sutherland LR, eds. Inflammatory Bowel Diseases. London: Churchill Livingstone. Elsevier Limited, 2003:169-181.
- Knutson D, Greenberg G, Cronau H. Management of Crohn's Disease- A practical approach. American Family Physician 2003;68:707-718.
- Forbes A. Clinical presentation and diagnosis of Crohn's disease. In: Satsangi J, Sutherland LR, eds. Inflammatory Bowel Diseases. London: Churchill Livingstone. Elsevier Limited, 2003:183-198.
- Schölmerich J, Warren B. Differential diagnosis and other forms of inflammatory bowel disease. In Satsangi J, Sutherland LR, eds. Inflammatory Bowel Diseases. Edinburgh, UK: Churchill Livingstone; 2003:199-217.
- Podolsky DK. Inflammatory bowel disease. N Engl J Med. 2002;347:417-429.
- D'Haens G, van Assche G, Baert F, Rutgeerts P. Imaging the gut in inflammatory bowel disease: endoscopy. In Satsangi J, Sutherland LR, eds. Inflammatory Bowel Diseases. Edinburgh, UK: Churchill Livingstone; 2003:237-253.