Morphological investigation of the enteric nervous system in Hirschsprung's disease and hypoganglionosis using whole-mount colon preparation

Background/Purpose: A suction rectal mucosal biopsy with positive staining for acetylcholinesterase is a useful test for diagnosis of Hirschsprung's d isease (HD). However, hypoganglionosis has not been diagnosed by a recta I mucosa I biopsy. The authors morphologically examined the enteric nervous s ystems in HD and hypoganglionosis patients using wholemount preparations. Methods: Six HD patients, two hypoganglionosis patients, and 10 with normal ly innervated colons were examined. Colonic specimens were incubated with t he primary antibodies against protein gene product 9.5 (PGP 9.5) mixed with S-100b protein, tyrosine hydroxylase (TH), calcitonin generelated peptide (CGRP), substance P (SP), and neurofilament protein 200 kDa (NFH). They wer e observed by histochemical technique using light-microscopy in whole-mount preparations. Results: The aganglionic distal colon had thick nerve strands stained with PGP 9.5 mixed with S100 or NFH located in the layer between the longitudina l muscle and the circular one, and the submucosal layer. The nerve strands in the myenteric layer contained few CGRP- and SP-positive fibers and ran a long the long axis of the intestine. Ganglion cells appeared along with tho se thick nerve strands in the transitional zone of HD. In hypoganglionosis, we found small myenteric ganglia with no thick nerve strands. Conclusions: The enteric nervous system in oligoganglionic segments of HD m orphologically differed from the one in hypoganglionosis. A suction rectal mucosal biopsy would be of no use in the diagnosis of hypoganglionosis. Cop yright (C) 1999 by W.B. Saunders Company.