The development of the characteristic anomalies found in gastroschisis--experimental and clinical data.

Gastroschisis was investigated experimentally as well as clinically. An experimental model developed in the chick embryo demonstrated that the characteristic picture of gastroschisis evolved only if the herniated bowel was exposed to urine components in the allantoic fluid. Remarkable similarities were revealed on comparing changes in human amniotic fluid composition (from 30th week) with changes in chicken allantoic fluid composition (from 15th day of incubation). These changes correlate with progressive fibrotic coating of the exposed bowel loops leading to the characteristic picture of gastroschisis. No fibrous coating was found in human foetuses with a gestational age under 30 weeks, while investigation of these foetuses did confirm that gastroschisis itself occurs at an early developmental stage (6th-8th week). No primary structural defects were found in the nervous system of the bowel wall neither in the experimental gastroschisis model nor in the human cases investigated. The postoperative delay in intestinal motility affecting some gastroschisis patients was found to be secondary to multifocal ischaemic damage of the bowel wall.