What are the common characteristics of inflammation in Crohn disease?

Updated: Jul 26, 2019
  • Author: Leyla J Ghazi, MD; Chief Editor: Praveen K Roy, MD, AGAF  more...
  • Print

The characteristic pattern of inflammation in Crohn disease is transmural involvement of the bowel wall by lymphoid infiltrates that contain noncaseating granulomas in about 15-30% of cases of biopsy samples and 40-60% of surgical specimens. A granuloma is defined as a collection of monocyte/macrophage cells and other inflammatory cells, with or without giant cells (see the image below).

Granuloma in mucosa of a patient with Crohn diseas Granuloma in mucosa of a patient with Crohn disease.

Other characteristics include proliferative changes in the muscularis mucosa and in the nerves scattered in the bowel wall and myenteric plexus. In the involved foci of the small and large bowel, Paneth cell hyperplasia is frequent, and areas of pyloric metaplasia may be seen. In severe cases, long and deep fissurelike ulcers form.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!