Prenatal Diagnosis of Gastroschisis

Introduction: Gastroschisis is defined as a congenital malformation distinguished by a visceral herniation, most often through a right sided abdominal wall defect with an intact umbilical cord and not covered by a membrane. It is unusual among congenital anomalies in that it disproportionately appears to impact younger patients, with the highest prevalence noted among those < 20 years of age (15.7/10,000). Etiology of the anomaly is controversial—multiple hypotheses have been proposed to elucidate the specific pathogenesis inclusive of rupture of the amniotic membrane at the base of the umbilical cord, abnormal involution of the right umbilical vein, abnormal folding of the embryo leading to a ventral wall defect or other exogenous factors (ex., toxins, drugs, viruses). We present a case of prenatally diagnosed gastroschisis.

Case Report: A 20-year-old G1P0 @ 20^3/7 weeks was referred for prenatal care. Her course was complicated only by an abnormal Quad screen notable for an increased risk of ONTD. Anatomical survey noted a right sided abdominal wall defect with intestinal protrusion consistent with gastroschisis. The patient underwent genetic/neonatal consultation; fetal echocardiographic assessment has been scheduled.

Discussion: Gastroschisis is classified into 2 categories—simple and complex—based on the condition of the fetal bowel at delivery. In simple gastroschisis, the bowel is without intestinal complications; complex is associated with complications in the form of atresia, perforation, ischemia, or volvulus. These issues are secondary to a combination of exposure to digestive compounds in the amniotic fluid coupled with ischemia due to mesenteric constriction at the level of the defect. Gastroschisis can be diagnosed as early as 12 weeks gestation. Approximately 5 to 15% have associated extra-intestinal anomalies, but syndromes and/or aneuploidies are rare. Maternal serum α fetoprotein levels are often elevated in abdominal wall defects, including gastroschisis.

Upon the diagnosis, a multidisciplinary team including the Ob/MFM, Neonatologist, Geneticist, Pediatric Surgeon, and Social Worker should provide counseling and be involved in the ongoing care of the patient and her fetus. Serial growth assessments and antenatal testing should be instituted as a significant number of fetuses are SGA, 30–40% have preterm birth, and 5% of the pregnancies have an IUFD. Mode of delivery is vaginal unless obstetrical indications prevail. Postnatally the goals of surgical management include reduction of the herniated viscera into the peritoneal cavity while avoiding direct trauma to the bowel, excessive intra-abdominal pressure, and subsequent closure of the defect.

Fig. 1 Ultrasound image showing fetus with gastroschisis.

Fig. 2 Ultrasound image showing profile of fetus with gastroschisis and its protrusion from right side of abdominal wall.

Fig. 3 Ultrasound image of Gastroschisis and its relation to umbilical insertion.

Publikationsverlauf

Artikel online veröffentlicht:
17. September 2021