An experimental study investigating the effects of intraperitoneal human neonatal urine and meconium on rat intestines

Urinary waste products (UWP) in the amniotic fluid have been held responsib le for the intestinal damage (ID) in gastroschisis, based on the fact that the fetus urinates physiologically into the amniotic cavity. However, exper imental and clinical evidence suggests that intrauterine defecation is a ph ysiological event; thus gastrointestinal waste products (GWP) may also be r esponsible for ID in gastroschisis. An experimental study was performed to investigate the effects of intraperitoneal human neonatal urine and diluted meconium on rat intestines. Adult Wistar albino rats were used. Sterile ur ine and meconium were obtained from newborn humans and 5% meconium suspensi on was prepared. Histopathological features of the intestines of the rats i njected with urine did not differ from the intestines of the untreated rats . The bowel in rats injected with a meconium suspension showed serosal thic kening, inflammation, focal fibrin and collagen deposits. Histopathological changes in intestines induced by intraperitoneal diluted meconium were con sistent with those described for human gastroschisis specimens. We conclude that GWP, rather than UWP, seems to be responsible for the ID in gastrosch isis.