The neuropathology of pseudo-obstruction of the intestine.

Destruction of the myenteric plexus impairs ongoing peristalsis and produces dilatation of the gut lumen with thickening of the gut wall. Achalasia of the cardia, hypertrophic pyloric stenosis and non-Hirschsprung megacolon are well-known examples of damage to the bowel nerve supply. There are many causes, some of which are unknown, but the common ones can be divided into three groups. Congenital developmental failure may be total and incompatible with life, or less severe, in which case resection may be possible. Acquired inflammatory damage, other than Chagas' disease, can occur anywhere in the gut. Autonomic neuropathy may involve either the neurons or the Schwann cells. The former is often due to drugs because the autonomic ganglia are outside the blood-brain barrier. The latter is frequently associated with metabolic disease, such as diabetes mellitus.