Cause

Exact cause of abdominal wall defects are not known.

Early in all pregnancies, the intestine develops inside the umbilical cord and then usually moves inside the abdomen a few weeks later. Occasionally, the intestine stays inside the umbilical cord and so develops outside the abdominal wall.

Types

There are various types of abdominal wall defect.

• If the intestine is contained inside a covering of membrane, this called an exomphalos. This can be either small or large
  
• If the intestine is not inside a covering of membrane, this is called a gastroschisis

Omphalocele

• An omphalocele is caused by an opening (defect) in the middle of the abdominal wall at the bellybutton (umbilicus)
• The skin, muscle, and fibrous tissue are absent.The intestines protrude through the opening and are covered by fine membranes
• The umbilical cord is in the center of the defect
• An omphalocele is commonly associated with other birth defects (such as heart defects)
• Surgical closure is the treatment of choice. However, the skin of the abdominal wall must often be stretched before surgery so there is enough tissue to cover the opening. Large defects sometimes also require skin flaps

Gastroschisis

• Gastroschisis is an abnormal opening of the abdominal wall, usually to the right of the umbilicus, which allows the uncovered intestines to spill out (herniate)
• Both conditions are diagnosed with prenatal ultrasound.In gastroschisis, the bowel may be damaged by compression and by exposure to amniotic fluid
• Surgical closure is the treatment of choice. Large herniations may require the creation of a "silo," in which the exposed bowel is wrapped in a protective covering and suspended above the baby for several days or weeks
• The silo is gradually compressed, forcing the intestines back into the abdomen

Diagnosis

• AFP screening
• fetal ultrasound
• Genetic testing such as amniocentesis

Treatment

Abdominal wall defects are effectively treated with surgical repair.

Unless there are accompanying anomalies, the surgical procedure is not overly complicated.

Small exomphalos- surgeons move the intestines back inside the abdomen and then close up the muscles and skin, making a belly button at the same time. This is called a ‘primary repair’ 

Large exomphalos and gastroschisis- Which operation your child has, depends on the size of the abdominal wall defect and the amount of intestine outside the abdomen.

Prognosis

If there are no other defects, the prognosis after surgical repair of this condition is relatively good. However, 10 percent of those with more severe or additional abnormalities die from it

• The outlook for children with gastroschisis is good, with the majority growing up to live normal lives
• The outlook for children with exomphalos varies, depending on the size of the defect and any other problems
• Many children have grown up to lead normal lives
• However, after surgery, increased pressure in the stretched abdomen can compromise the function of the organs inside, and even the chances of hernia is more.

Parental Concerns

Parents will need to work closely with a team of physicians during the treatment of their child.

Children with abdominal wall defects may need additional services, especially those with omphalocele and associated chromosomal abnormalities and birth defects.

These children require long-term treatment for both the physical and developmental difficulties they face.