The etiology of several motility disorders, including persistent megacolon after definitive surgery for Hirschsprung's disease, meconium ileus which is not associated with cystic fibrosis and idiopathic megacolon, is still unclear. Interstitial cells of Cajal (ICC) are thought to modulate gut motility as gastrointestinal pace maker cells. The aim of this study was to evaluate the role of ICC in the bowel walls of the patients (n=15) who had variable motility disorders. The ICC were identified by immunohistochemical staining using an anti-C-Kit antibody and the results were compared with control specimens (n=2). The control group (G1) showed evenly distributed ICC in their bowel walls. The second group (G2, n=5) who had normal bowel movements after Duhamel procedures and the third group (G3, n=4) who had persistent megacolon after Duhamel procedures showed absent or scarcely distributed ICC in their aganglionic bowels. The ICC were identified by immunohistochemical staining using an anti-C-Kit antibody and the results were compared with control specimens (n=2). The control group (G1) showed evenly distributed ICC in their bowel walls. The second group (G2, n=5) who had normal bowel movements after Duhamel procedures and the third group (G3, n=4) who had persistent megacolon after Duhamel procedures showed absent or scarcely distributed ICC in their aganglionic bowels. Whereas ICC were evenly distributed in the ganglionic bowels of G2, they were not seen or scarecely distributed in the ganglionic bowels of G3. Two patients (G4) who suffered from idiopathic megacolon showed absence or decrease of ICC in spite of presence of ganglion cells in their colons. Four neonates (G5) who underwent ileostomy because of meconium obstruction showed absent or markedly decreased ICC in the colon at the time of ileostomy and the distribution of ICC was changed to a normal pattern at the time of ileostomy closure between 39-104 days of age and their bowelmotility were restored after that. The results suggest that lack of ICC caused reduce motility in the ganglionic colons and it may be responsible for the development of various motility disorders. Delayed maturity of ICC may also play a role in the meconium obstruction of neinates.

Hirschsprung's disease (HD) is usually diagnosed in the newborn period and early infancy. The common presentation of HD in newborns consists of a history of delayed passage of meconium within the first 48 hours of life. The differential diagnosis in newborns is one of the clinical challenges of this disorder. A number of medical conditions which cause functional obstruction of the intestines are easily excluded. Neonates with meconium ileus, meconium plug syndrome, distal ileal atresia and low imperforate anus often present in a manner similar to those with HD in the first few days of life. Abdominal radiographs may help to diagnose complete obstruction such as intestinal atresia. Microcolon on contrastenema can be shown in cases with total colonic aganglionosis, ileal atresia or meconium ileus. Suction rectal biopsy or frozen section biopsy at operation is essential for differential diagnosis in such cases. HD is also considered in any child who has a history of constipation regardless of age. Older children with functional constipation may have symptoms that resemble those of HD and contrast enema is usually diagnostic. However, children with other motility disorders generally referred to as chronic idiopathic intestinal pseudoobstruction present with very similar symptoms and radiographic findings. These disorders are classified according to their histologic characteristics.; visceral myopathy, visceral neuropathy, intestinal neuronal dysplasia (IND), hypoganglionosis, immature ganglia, internal sphincter achalasia. Therefore, the workup for motility disorders should include rectal biopsy not only to confirm the presence of ganglion cells but also evaluate the other pathologic conditions.