Immunocytochemistry for neuronal markers shows deficiencies in conventional histology in the treatment of Hirschsprung's disease.

Despite technically satisfactory operations, at least 20% of children with Hirschsprung's disease have an unsatisfactory postoperative result. A possible explanation for their symptoms is the retention of ganglionic intestine which has demonstrable abnormalities of the enteric nervous system. The distribution of intestinal neural proteins and peptides in resected colons from patients with Hirschsprung's disease (n = 10) was compared with that in normal controls (n = 5). Immunocytochemistry was performed using antisera against general markers of the enteric nervous system (PGP 9.5, NSE, NFILs, and S-100 protein) and colonic neuropeptides (VIP, GAL, SP, NPY, CGRP, and Met-ENK). The distribution and density of peptide-containing nerve fibers varied greatly from one patient to another and no consistent pattern of neural disturbances could be discerned in aganglionic colon. At the proximal limit of resection, abnormalities of enteric innervation were detected in 8 of 10 studied specimens. Although ganglion cells staining positively for general neuronal markers were present in all cases, normal populations of neural cell bodies immunoreactive for neuropeptides could be found in only 2 specimens. Enlarged submucosal nerve trunks found in the most proximal area of most specimens, displayed immunoreactivity for general nerve markers and VIP, GAL, NPY, and CGRP. The widely practised conventional histopathological assessment of the proximal limit of colonic neural abnormalities may be inadequate.