What histological feature is characteristic of Crohn's disease?

Crohn's disease is characterized histologically by the presence of non-caseating granulomas. These granulomas arise due to the body's immune response to various antigens, often involving the gastrointestinal tract, particularly the ileum and colonic areas. The granulomatous inflammation in Crohn's disease can lead to transmural inflammation, resulting in complications such as strictures, fistulas, and abscesses.

Non-caseating granulomas in Crohn's disease differ from the caseating granulomas commonly associated with conditions such as tuberculosis. This distinctive histological feature, along with other characteristics like lymphocytic infiltration and mucosal fissuring, helps in differentiating Crohn's disease from other inflammatory bowel diseases, particularly ulcerative colitis, which typically does not show granulomas.

The significance of recognizing these granulomas lies in their role in confirming a diagnosis when clinical and radiological findings suggest Crohn's disease. Other features such as crypt abscesses are more often associated with ulcerative colitis, and squamous metaplasia does not pertain to Crohn's disease but is more relevant in other contexts, such as certain types of malignancies or chronic irritation.