Crohn's Disease and Ulcerative Colitis
Both the diseases, Ulcerative Colitis and Crohn's Disease, while seemingly related, are distinct diseases in terms of etiology, pathology, clinical presentation and prognosis. A summary table highlighting these attributes in presented below:
| PARAMETER | CROHN'S DISEASE | ULCERATIVE COLITIS |
|---|---|---|
| Sex Ratio | 02:01:00 | 01:01:00 |
| Role of Genetics in causation | Greater | Minimal or nil |
| Cigarette-smoking Relationship | Smokers are at greater risk of developing CD (nicotine can aggravate disease) | Ex-smokers and Non-smokers are at greater risk of developing UC (nicotine may be preventive) |
| Immunological Culprit | Inflammation though to be triggered by Th1 cells; IL-12 is increased | Inflammation though to be triggered by Th2 cells; IL-5 is increased |
| Commonly Involved areas | Ileum & Proximal Colon | Distal Colon & Rectum |
| Typical symptoms | Abdominal pain, weight loss, diarrhea, fever | Abdominal pain, weight loss, diarrhea, rectal bleeding, |
| Blood & mucus from rectum | Rare | Common |
| Abdominal mass | May be present in right-lower quadrant of abdomen | Rare |
| Extra-intestinal manifestations | Common | Common |
| Ileus (reduced or absent motility of intestines) | Common | Rare |
| Colonic obstruction | Common | Rare |
| Perianal fistula | Common | No |
| Protein-Calorie Malnutrition | More likely (25-80% have hypoalbuminemia) | Less likely (25-50% have hypoalbuminemia) |
| Nutritional status | Relatively poor | Better preserved |
| Nature of Involvement | Interrupted lesions (skip-lesions common) | Uninterrupted lesions |
| Extent of Inflammation | Transmural (can extend through the thickness of the wall) | Limited to mucosa |
| Associated lesions/pathologies | Strictures, Fistulas, Granulomas | None of these |