Meconium staining of amniotic fluid correlates with intestinal peel formation in gastroschisis

Several studies in animal models demonstrate that peel formation in gastroschisis is due to the accumulation and activation of intestinal waste products (IWP) in the amniotic fluid. We reviewed our recent experience with gastroschisis and asked the following questions: First, does staining of the bowel and amniotic fluid with IWP correlate with intestinal peel formation? Second, what prenatal ultrasound findings indicate that peel formation is occurring in utero? Over two years, 16 neonates were treated for gastroschisis; twelve had been diagnosed by prenatal ultrasound and followed closely. Patients were grouped based on the presence of IWP in the amniotic fluid at the time of delivery (staining or no staining), and outcomes were reviewed. All neonates in the staining group (n=7) had a fibrinous peel present at the time of birth whereas a peel was absent in all neonates in the no-staining group (n=9). Matting of the bowel was seen by prenatal ultrasound in four patients in the staining group (0/8 in the no-staining group) and correlated with peel formation (Fisher's exact test p =0.007). Primary closure was done in 14 of the infants, and two required silo closure. In neonates with gastroschisis, staining of the amniotic fluid and bowel serosa with IWP correlated with intestinal peel formation. The ultrasound findings of matting correlated with both peel formation and staining with IWP. These results suggest that spillage of IWP into the amniotic fluid is one of the factors in peel formation in gastroschisis. Identification of matting of the bowel by prenatal ultrasound indicates formation of a peel.