Crohn disease of the small intestine: diffuse mucosal granularity.

A diffuse granular mucosal pattern, produced by a reticular network of radiolucent foci 0.5 to 1 mm in diameter, was identified in 39 out of 46 consecutive patients with Crohn disease of the small intestine. Resected specimens demonstrated that this pattern represented wide, blunted villi with lymphocytic infiltration. Such a pattern was the only evidence of small bowel involvement in 17 cases. In 3 patients with the commonly recognized lesions, separate regions of diffuse granularity were seen. No such pattern was detected in normal patients. Demonstration of diffuse granularity may contribute to the diagnosis and management of Crohn disease.