ABSTRACT
Hirschsprung's disease (HD) is a relatively common cause of intestinal obstruction in the newborn. It is characterized by absence of ganglionic cells in the distal bowel beginning at the internal sphincter and extending proximally for varying distances. The enteric nervous system (ENS) is the largest and the most complex division of the peripheral nervous system. It provides the gastrointestinal tract with its unique network of innervation within its walls and functions largely independently of the central nervous system (CNS). Genetic factors have been implicated in the etiology of HD. HD is known to occur in families. During the past 15 years, several genes have been identified that control morphogenesis and differentiation of the ENS. These genes, when mutated or deleted, interfere with ENS development. It has long been recognized that obstructive symptoms in HD are secondary to the abnormal motility of the distal narrow segment, but there is still no explanation for occurrence of the spastic contracted segment of bowel.
