Association of antral diaphragms and hypertrophic pyloric stenosis.

In a 2 year period at Children's Hospital of Philadelphia, seven human infants and a baby orangutan all presented with a previously unreported association of a prepyloric membrane and hypertrophic pyloric stenosis. In the humans, the pyloric stenosis was the obstructive lesion, and in the orangutan, the web. We also report a 6-year-old patient with previous pyloromyotomy who presented because of prolonged retention of a marble in the stomach by an associated antral membrane.