Intact colonic mucosa showing mild infiltration by lymphocytes and plasma cells. There is complete absence of ganglion cells of the submucosal (Meissner's) and myenteric (Auerbach's) nerve plexuses Picture is consistent with aganglionic segment (Hirschsprung's disease). Margins are ganglionic. Lymph nodes show reactive follicular hyperplasia with sinus histiocytosis 0/4.
Surgical resection of the sigmoid-rectal region.
Part of sigmoid colon measuring 4.5 x 1.5 x 1 cm, with attached mesenteric fat measuring 3.5 x 2 cm. Opening revealed no gross masses nor ulceration and representative sections were taken. Sectioning of the attached mesenteric fat revealed four lymph nodes, the largest of which measured 0.5 cm in maximum dimension.