Enterochromaffin cells in macrophages in ulcerative colitis and irritable colon.

Rectal biopsies from 6 patients with ulcerative colitis, 6 patients with irritable colon and 9 control patients were studied by formaldehyde-induced fluorescence after freeze-drying and Epon embedding. The mean number of enterochromaffin cells per crypt was higher in the patients with irritable colon whereas the patients with ulcerative colitis had fewer enterochromaffin cells than the controls. There was an abundance of enterochromaffin cells in 5 of the 6 cases of irritable colon. Various types of autofluorescent granules were visible in the cytoplasm of the macrophages.