Colonic aberrant crypts in children with familial adenomatous polyposis.

Aberrant crypt foci of the colonic mucosa have been reported in adults. The alteration may be defined macroscopically or histologically and may or may not be combined with adenomatous changes. Aberrant crypt foci have been regarded as precancerous lesions and are more common in patients with familial adenomatous polyposis. The present report describes the presence of many histologically recognizable aberrant crypt foci without adenomatous changes in the colonic mucosa of 3 children with familial adenomatous polyposis. The openings of the aberrant crypt foci contained inspissated granulofilamentous mucus. Additionally, this report documents the presence of a peculiar serrated appearance of the mucosae surface outline of the nonadenomatous areas. This appears to result from elongation of the crypts and dilated openings/micropapillary arrangement of the uppermost part of the walls of the crypts, with a thin intervening stroma. Neither of these findings has been reported previously to occur in children. They may represent the earliest histologically identifiable changes ever recorded in the colon of patients with familial adenomatous polyposis.