Gastrointestinal myoelectric activity in an infant with congenital idiopathic motility disorder.

We investigated myoelectric activity in an 8-month-old male who presented with a perinatal bowel obstruction, duodenal band, congenital short small intestine, and persistent feeding intolerance. Serosal electrodes were surgically implanted on stomach, duodenum, and jejunum during Nissen fundoplication and ileostomy. A 5-cm ileal specimen was taken for in vitro studies. Spontaneous migrating myoelectric complexes (MMC) were present in stomach and small intestine. Bethanechol increased electrical response activity (ERA) in stomach and duodenum. Morphine induced intense ERA and distinct phase III activity. Pentagastrin infusion did not disrupt MMC cycling. Feeding disrupted MMC complex cycling 30-40 min after the meal. Metoclopramide before feeding delayed disruption of the MMC cycling after the feeding. Intermittent gastric arrhythmias were present after the fifth postoperative day. In vitro muscle strips showed spontaneous contractions and electrical control activity (ECA). Bethanechol, McNeil A-343, motilin, and cholecystokinin induced contractions, but pentagastrin had no effect. We conclude that in spite of a major clinical motility dysfunction, several of our findings were normal. The abnormalities include short MMC period, absence of disruption of MMC by pentagastrin, and gastric arrhythmias.