Gastroschisis is the herniation of the intestines through an opening in the abdominal wall. It is a congenital defect that can be detected prenatally using imaging technologies, mainly ultrasonography. In most cases, the surgical intervention is performed on the first day after birth. In complicated cases, the repair is done in stages using a pouch (a silo) to contain extruded bowels, and wall closure is achieved over one or two weeks.
Presentation
There are several types of congenital abdominal wall defects that result in the extrusion of bowels and other organs, with gastroschisis being the most frequent. Gastroschisis and omphalocele are both examples of an abnormal opening in the abdominal wall that results in the bowels protruding out of the abdomen into the amniotic sac, but they are different, well-defined conditions. Omphalocele is associated with chromosomal aberrations and malformations in several other organs; in this condition, a membrane surrounds the externalized intestines. Gastroschisis does not tend to be associated with chromosomal abnormalities or problems with other organs, and there is no membranous covering on the extruded bowels.
Gastroschisis is a relatively common congenital defect affecting about 1 in 2000 births [1]. There has been a recent increase in its prevalence. The opening in the abdominal wall is mainly to the right of the umbilical cord. The herniated organ is most often the small bowel, which is not rotated. The bowels are exposed to the amniotic fluid, which may lead to a decrease in its functional capacity. Exposure to the amniotic fluid also results in increased levels of maternal alpha-fetoprotein, the detection of which may lead to the discovery of gastroschisis. Other clues for gastroschisis are fetal growth retardation and polyhydramnios [2]. Gastroschisis may also be discovered by chance during a second-trimester sonography. Fetal abdominal circumference is low in gastroschisis, making the assessment of the age of the fetus difficult [2]. Very low abdominal circumference and an abnormal gastric bubble are among the indicators for increased perinatal death or serious bowel injuries such as necrotizing enterocolitis [3]. In one study, babies with gastroschisis delivered between 35 and 37 gestational weeks were found to have the fewest perinatal complications [4].
Workup
The most important imaging tool for the diagnosis of gastroschisis is antenatal ultrasonography, which is the cornerstone of imaging in pregnancy because it is noninvasive and not associated with exposure to radiation. Radiography is only used in the postnatal period and, for the same reason, the application of computerized tomography (CT) is inappropriate antenatally.
Ultrasonography allows for the detection of the location and features of the abdominal faults and differentiates amongst the different types of abdominal anomalies [5]. In the case of gastroschisis, the herniated bowels have no membranous covering; thus, the image shows free-floating bowel loops with irregular shapes. Although the small bowel is most frequently extruded, other organs may also be found floating in the amniotic fluid, such as the large intestines, stomach, urinary bladder, uterus, fallopian tubes, and testes. The extruded intestines may be inflamed and swollen.
Various studies have examined the value of fetal intestinal and other features detected by ultrasonography in predicting later complications. In addition to the signs mentioned above in connection with adverse outcomes, several other characteristics have been studied as predictors of complications. Intra-abdominal bowel dilatation and polyhydramnios were both associated with bowel atresia [6]. The predictive value of extra-abdominal dilatation is questionable: although one recent study found a significant association between extra-abdominal bowel dilatation and morbidity, a large percentage of patients with this type of anomaly were free from complications [7]. Magnetic resonance imaging (MRI) is used mainly in complicated cases or where ultrasound results are equivocal.
Treatment
Treatment for gastroschisis involves surgical intervention shortly after birth. The primary goal is to protect the exposed organs and return them to the abdominal cavity. This may be done in a single surgery or in stages, depending on the severity of the condition and the size of the defect. In some cases, a silo, a special medical device, is used to gradually move the organs back into the abdomen over several days. Post-surgery, the infant will require supportive care, including nutrition and infection prevention, until they recover.
Prognosis
The prognosis for infants with gastroschisis has improved significantly with advances in surgical techniques and neonatal care. Most infants can recover fully with appropriate treatment, although they may face challenges such as feeding difficulties and slower growth initially. Long-term outcomes are generally positive, but some children may experience digestive issues or require additional surgeries. Early diagnosis and prompt treatment are crucial for the best outcomes.
Etiology
The exact cause of gastroschisis is not well understood, but it is believed to result from a combination of genetic and environmental factors. It occurs when the abdominal wall fails to form properly during fetal development. Some studies suggest that young maternal age, smoking, and certain medications or environmental exposures during pregnancy may increase the risk of gastroschisis, but more research is needed to confirm these associations.
Epidemiology
Gastroschisis is a relatively rare condition, affecting approximately 1 in 2,000 to 5,000 live births worldwide. The incidence of gastroschisis has been increasing over the past few decades, particularly among younger mothers. It is more common in infants born to mothers under the age of 20. The reasons for this increase are not fully understood, but it highlights the importance of monitoring and research.
Pathophysiology
Gastroschisis occurs due to a defect in the development of the abdominal wall during early pregnancy. Normally, the intestines develop outside the fetus's body and then move back inside as the abdominal wall closes. In gastroschisis, this closure does not occur properly, leaving a gap through which the intestines and sometimes other organs protrude. The lack of a protective sac around the organs increases the risk of damage and complications.
Prevention
Currently, there are no specific measures to prevent gastroschisis, as its exact causes are not fully understood. However, general recommendations for a healthy pregnancy may help reduce the risk. These include avoiding smoking, alcohol, and certain medications during pregnancy, maintaining a healthy diet, and receiving regular prenatal care. Research is ongoing to better understand the risk factors and potential preventive strategies for gastroschisis.
Summary
Gastroschisis is a congenital defect where an infant's intestines and sometimes other organs protrude outside the body due to an opening in the abdominal wall. It is typically diagnosed prenatally and requires surgical intervention after birth. While the condition poses significant challenges, advances in medical care have improved outcomes for affected infants. Understanding the risk factors and ensuring early diagnosis and treatment are key to managing gastroschisis effectively.
Patient Information
If your child is diagnosed with gastroschisis, it is important to work closely with a team of healthcare professionals, including obstetricians, pediatric surgeons, and neonatologists, to plan for delivery and treatment. Surgery will be necessary to repair the defect and protect the exposed organs. After surgery, your child will need specialized care to support their recovery and growth. With appropriate treatment, most children with gastroschisis can lead healthy lives.
References
- Eggink BH, Richardson CJ, Malloy MH, Angel CA. Outcome of gastroschisis: a 20-year case review of infants with gastroschisis born in Galveston, Texas. J Pediatr Surg. 2006;41(6):1103-1108.
- Siemer J, Hilbert A, Hart N, et al. Specific weight formula for fetuses with abdominal wall defects. Ultrasound Obstet Gynecol. 2008;31(4):397-400.
- Sinkey RG, Habli MA, South AP, et al. Sonographic markers associated with adverse neonatal outcomes among fetuses with gastroschisis: an 11-year, single-center review. 2016;214(2):275.e1-275.e7.
- Mesas Burgos C, Svenningsson A, Vejde JH, Granholm T, Conner P. Outcomes in infants with prenatally diagnosed gastroschisis and planned preterm delivery. Pediatr Surg Int. 2015;31(11):1047-1053.
- Fogata ML, Collins HB 2nd, Wagner CW, Angtuaco TL. Prenatal diagnosis of complicated abdominal wall defects. Curr Probl Diagn Radiol. 1999;28(4):101-128.
- D'Antonio F, Virgone C, Rizzo G, et al. Prenatal Risk Factors and Outcomes in Gastroschisis: A Meta-Analysis. Pediatrics. 2015;136(1):e159-169.
- Robertson JA, Kimble RM, Stockton K, Sekar R. Antenatal ultrasound features in fetuses with gastroschisis and its prediction in neonatal outcome. Aust N Z J Obstet Gynaecol. 2017;57(1):52-56.