Crohn disease: sites

esophagus: rare
stomach (2-20%): granulomatous gastritis
- pseudo-post Bilroth-I appearance
- "ramshorn sign"
- antral-duodenal fistula
duodenum (4-10%):
- almost always associated with gastric involvement
- bulb and proximal half of duodenum
small bowel (80%): regional enteritis
- terminal ileum (alone/in combination): 95%
- jejunum/ileum: 15%
- commonly associated with medial cecal defect
colon (22-55%): granulomatous colitis
- particularly on the right side
- "transverse stripe sign": contrast within coarse mucosal folds
rectum (35-50%)

Yong H. Hahn, MD - 2 February 1995
Last updated: 1 October 2013