Intestinal neuronal dysplasia is a possible cause of persistent bowel symptoms after pull-through operation for Hirschsprung's disease.

The proximal margin of the resected bowel specimens from 33 consecutively treated patients undergoing a definitive pull-through operation for Hirschsprung's disease (HD) and control specimens consisting of suction rectal biopsy specimens obtained from 24 age-matched patients evaluated for constipation (and proven not to have HD) were examined using conventional H&E staining and acetylcholinesterase (AChE) histochemistry. Complete resection of the aganglionic segment was confirmed in 31 patients. In one patient, the proximal margin was found to be aganglionic; in another, the proximal margin was in a transitional zone. In both patients, frozen sections at the time of surgery were interpreted as having ganglion cells. In 10 of 31 patients, intestinal neuronal dysplasia was demonstrated in the proximal margin of the resected bowel. The abnormalities included hyperplasia of the submucous plexus, giant ganglia (with > 7 ganglion cells), and ectopic ganglion cells (all 10 patients) and increased AChE activity in the lamina propria (5 patients). All ten patients with IND had persistent bowel problems after the definitive operation for HD, such as enterocolitis, soiling, or constipation. Only four of the other 21 patients had persistent bowel symptoms. This study suggests that IND is commonly associated with HD. It also emphasizes the importance of histochemical examination of the resected segment to predict postoperative bowel function in patients with HD.