| Subcategory |
Area Affected |
| Ileocolitis |
The most common form of Crohn's Disease, affecting the ileum and colon |
| Ileitis |
Affects only the ileum; fistulas or inflammatory abscesses possible |
| Gastroduodenal Crohn's Disease |
Affects the stomach and duodenum; bowel obstruction possible |
| Jejunoileitis |
Patchy areas of inflammation in the jejunum; fistulas possible |
| Crohn's (Granulomatous) Colitis |
Affects only the colon and anus; anal fistulas, abscesses, and ulcers possible |