What is Omphalocele?
Omphalocele is a rare birth defect that affects about 3.38 in every 10,000 pregnancies. This condition causes a baby’s abdominal organs to stick out through the base of the umbilical cord, but they’re covered by a layer of tissue called the peritoneum. While omphalocele can occur on its own, it’s usually seen alongside other birth defects and conditions like Beckwith-Wiedemann syndrome and Trisomies 13, 18, and 21.
The survival rate for babies with this condition is around 80%. However, survival rates are linked to the severity of any other associated defects. Babies who only have omphalocele without any other conditions have a survival rate as high as 90%.
What Causes Omphalocele?
Omphalocele, a birth defect where the baby’s organs stick out of the belly button, can be linked with several health conditions. One of the most common is Beckwith-Wiedemann syndrome. This syndrome often results in large body size, an oversized tongue, low blood sugar in newborns, lines or holes in the ears, inconsistent body growth, enlarged internal organs, belly button hernia, embryonic tumors, kidney problems, enlarged heart and kidneys.
These features often appear right after birth. The unusual growth can happen in parts of the body or specific organs. Though the physical growth is unusual, thinking and learning abilities are generally normal. However, there’s an increased risk of certain cancers, like neuroblastoma, hepatoblastoma, and Wilms tumor, early in life. These cancers are often more treatable when spotted early, so regular screenings are necessary for prevention. These include checks for hepatoblastoma done by measuring a protein in the blood called alpha-fetoprotein every 3 months until age 4. Wilms tumor is checked for every 3 months until age 8 through a full ultrasound scan of the belly.
Omphalocele can also be associated with other health conditions, such as:
* Trisomy 13 (Patau syndrome): Small eyes, cleft lip and palate, small head, undescended testicles, extra fingers or toes, wide-set eyes, small lower jaw, missing scalp skin, and ear deformities.
* Trisomy 18 (Edwards syndrome): Elongated head, ear deformities, tiny lower jaw, small eye openings, small face, clenched hand with overlapping fingers, low muscle tone, and rounded bottom feet.
* Trisomy 21 (Down syndrome): Low muscle tone, slanting eye openings, shortened head, low set ears, single line in the palm of the hand, flat nose bridge, white spots around the iris, bent fifth finger, and a space between the first and second toes.
Other conditions linked with omphalocele are Pentalogy of Cantrell (heart abnormalities, mid-line stomach wall defects, sternum cleft, and heart defects), Shprintzen-Goldberg syndrome (early fusion of skull bones, elongated head, wide-set eyes, bulging of the eyes, crossed eyes, long fingers and limbs, belly button and stomach wall hernia), Charge syndrome (eye coloboma, heart defects, nostril structure defects, growth delay, genital issues, and ear deformities), and Cloacal exstrophy (bladder exstrophy, anal defects, spinal deformities).
Also associated are Carpenter syndrome (cloverleaf skull from early fusion of skull bones, webbed fingers and toes, intellectual disabilities), Marshall-Smith syndrome (prominent forehead, shallow eye sockets, blue whites of the eyes, depressed nose bridge, small lower jaw, fast skeletal growth, breathing issues, intellectual disabilities), and Meckel-Gruber syndrome (brain sac-like protrusion at the back of the skull, cleft lip and palate, small head, small eyes, genital abnormalities, cyst-filled kidneys, and extra fingers or toes).
Risk Factors and Frequency for Omphalocele
In the United States, omphalocele, a type of birth defect, affects about 1.86 out of every 1000 babies. Its occurrence increased by 11% between 1999-2001 and 2005-2007. This condition tends to occur more often in women who are either under 20 or over 40. It is more commonly seen in black people compared to white people. The chances of omphalocele also seem higher for multiple births and for male babies.
- The rate of omphalocele in the U.S. is 1.86 per 1000 live births.
- From 1999-2001 to 2005-2007, the prevalence of omphalocele rose by 11%.
- Women under 20 or over 40 have a higher chance of having a baby with omphalocele.
- Omphalocele seems to occur more frequently in black people than in white people.
- Multiples births and male babies have been associated with omphalocele.
Signs and Symptoms of Omphalocele
When a child is born with omphalocele, it is usually diagnosed right away through a physical examination. The clue is the presence of a bump on the baby’s belly where the umbilical cord is attached. This bump is enveloped by a thin layer of tissue. The size and content of this bump can vary. In some babies, it may be small, with only a little bit of the intestines poking through. In other cases, it might be large, containing various belly organs. If the defect is bigger than or equal to 5 centimeters, with a portion of the liver coming out, it’s called a giant omphalocele. These infants often have issues with lung function because the omphalocele can interfere with the chest’s normal expansion. Therefore, deciding when and how the omphalocele is fixed is very important.
Testing for Omphalocele
Doctors use a type of ultrasound method to diagnose omphalocele, a condition that causes some of an infant’s organs to develop outside their body in their belly-button area, during pregnancy. This ultrasound testing is usually able to show almost all instances of omphalocele by the end of the first three months of pregnancy. In addition to this, a blood test that measures the level of alpha-fetoprotein (a protein made by the baby and passed into the mother’s bloodstream) in the mother’s blood can also indicate the presence of an omphalocele.
Once a baby is born with an omphalocele, further tests are needed. These tests will check for any associated conditions like Beckwith-Wiedemann syndrome or Prader-Willi syndrome, which are genetic disorders that may occur alongside omphalocele. These disorders can cause various complications and health issues in the child’s growth and development.
Treatment Options for Omphalocele
Omphalocele is a birth defect where an infant’s intestine or other abdominal organs are outside of the body because of a hole in the belly button area. The treatment for newborn babies born with omphalocele generally starts with ensuring the baby can breathe properly. Following this, doctors place a sterile wrap around the exposed organs to help keep them warm and reduce fluid loss. They may also insert a special tube through the baby’s mouth into the stomach to release any built-up gas and fluid, and secure a vein for giving fluids or medications.
If the baby’s heart rate increases, their blood pressure is low, or the organs outside of their body look discolored, the baby is positioned on their left side with their right side raised. This can help improve the blood flow. It’s important that doctors avoid using dressings that are too wet or wrap around the whole body because they can hurt the baby’s omphalocele or interrupt the blood flow. While caring for the baby, doctors provide necessary fluids and antibiotics through a vein to fight infections.
If the baby’s omphalocele is small, surgery is possible within the first 72 hours after birth, where the skin and tissue layers are closed up. If there are other health concerns, a protective pouch is used to gradually push the organs back into the abdomen over the course of 3 to 7 days, prior to final closure of the tissue. Large omphaloceles, especially those containing the liver, can be more complex and challenging to repair. Doctors often use a patch to close up large openings.
After the closure, these babies can usually tolerate oral feeding soon after. Topical antibiotics are usually applied to the belly button area until it completely heals.
What else can Omphalocele be?
Gastroschisis is often confused with omphalocele. In gastroschisis, the intestines stick out typically to the right of the belly button and the umbilical cord is not affected. One key way to tell these two conditions apart is the presence of a membranous sac. In gastroschisis, the intestines are exposed, but in omphalocele, there is often a membrane that may rupture while the baby is still in the womb.
Other conditions that may have symptoms similar to omphalocele are:
- Hernias of the umbilical cord with covered abdominal wall defects smaller than 2 cm
- Body stalk anomaly, which shows an unusually short or missing umbilical cord and is associated with scoliosis (curvature of the spine)
What to expect with Omphalocele
The outlook for patients largely depends on the size of the abnormality and any associated birth defects and conditions. As such, larger omphaloceles, a type of birth defect where an infant’s intestine or other abdominal organs are outside of the body because of a hole in the belly button area alongside other physical abnormalities, typically have a higher mortality rate.
A poorer prognosis is also seen in newborns with liver protrusion, or when the liver sticks out through the defect. However, the overall survival rate is close to 80%. This high rate is a reflection of the effectiveness of prenatal diagnosis, which is the testing for diseases or conditions in a fetus or embryo before it is born.
This diagnosis allows many families to make an informed decision about whether to continue with a pregnancy if severe abnormalities are detected.
Possible Complications When Diagnosed with Omphalocele
Complications related to omphalocele, a birth defect where the baby’s organs bulge out from the belly, can happen at different stages. During pregnancy and delivery, the omphalocele may rupture, potentially damaging the liver if the omphalocele is particularly large. Because omphalocele babies often have smaller chests and undersized lungs, they frequently require assistance with breathing for an extended period until their lungs develop further.
These babies usually need to be fed through a vein (parenteral nutrition), which can lead to additional problems like cholestasis (a condition where bile cannot flow from the liver to the gut) and an enlarged liver (hepatomegaly). Therefore, large omphaloceles often need repair surgeries performed in stages. Moreover, until the lungs are fully mature, a windpipe opening (tracheostomy) may be required.
After birth and surgery, babies may face complications like difficulty in eating, slow growth, hernias in the groin, gastric acid reflux, and rare cases of esophagitis (inflammation in the food pipe). Compared to another birth defect called gastroschisis, omphaloceles have a higher risk of causing death.
Common Complications:
- Omphalocele rupture
- Liver injury
- Small chest and underdeveloped lungs
- Need for mechanical ventilation for lung development
- Need for parenteral nutrition y
- Cholestasis and hepatomegaly
- Need for staged repair surgeries
- Requirement of tracheostomy
- Feeding difficulties
- Slow growth
- Inguinal hernias
- Gastroesophageal reflux
- Esophagitis
- Higher mortality compared to gastroschisis