Hirschsprung's disease: the importance of early diagnosis.

Congenital intestinal aganglionosis, also called Hirschsprung disease (HD), is defined as the absence of ganglionic cells in the myenteric (Auerbach) and submucosal (Meissner) plexus, due to a failure in the enteric nervous system development. The extent of intestinal involvement may vary according to the age of embryo development in which this failure occurs. It is not unusual for other malformations to be present, as well as chromosomal trisomies, manly trisomy 21.