Hirschsprung's disease: a review of the morphology and physiology.

MANY theories have been postulated to account for 'congenital megacolon' since the classical description by Hirschsprung in 1888. At first the dilated bowel of the megacolon attracted most of the attention but later most features of the disease were attributed to the absence of ganglion cells in an undilated segment of distal bowel. More recently, however, morphological and physiological observations have suggested that the cause is a more complex abnormality of innervation which involves not only the ganglion cells but also the distribution of adrenergic and cholinergic nerves within the bowel wall. Variations in this abnormal innervation may account for differences in the clinical progress and presentation of patients with Hirschsprung's disease.