Gastrointestinal amyloidosis: radiologic features by chemical types.

PURPOSE: To determine the correlation between the radiographic and histologic findings of amyloidosis according to chemical type of amyloid protein. MATERIALS AND METHODS: The 49 patients with amyloidosis were examined radiographically, and gastrointestinal tract biopsy specimens were studied histologically. RESULTS: Considerable differences were found between amyloid proteins. On immunohistochemical studies, amyloid A produced a coarse mucosal pattern with innumerable fine granular elevations, which reflected expansion of the lamina propria by amyloid deposits. Polypoid protrusions and invariable thickening of the folds were evident only in light chain protein, correlating with massive amyloid deposits in the muscularis mucosae and submucosa. beta 2-Microglobulin produced marked delay in transit time and dilatation of the small and large intestines, relating to extensive amyloid deposits in the muscularis propria. The prevalence of these radiographic changes was highest in the small intestine for every c...