Definition

Omphalocele, or exomphalos, is a congenital disability in which the abdominal organs, such as the intestines, liver, or other abdominal organs, protrude through a breach in the navel due to a deficiency in the baby's abdominal wall. The peritoneal layer is a delicate and translucent membrane that envelops these organs. This pouch can either open or rupture. An omphalocele can involve either a partial protrusion of the intestine or a substantial protrusion of the intestine, along with multiple organs from the abdominal cavity.

The prevalence of omphalocele in the United States is approximately 1 in 4,200 births. Most babies born with omphalocele also have other birth defects, such as problems with their hearts, brains, skeletons, intestines, bladders, or faces. Some babies also have chromosomal problems because of genetic mutations or syndromes. These conditions may impact limb development and contribute to learning disabilities, mental disorders, or behavioral issues in affected children. The syndromes encompass Beckwith-Wiedemann syndrome, Prader-Willi syndrome, Patau syndrome, Edwards syndrome, and Down syndrome.

Causes

During the sixth to tenth week of pregnancy, the internal organs of the fetus undergo a period of rapid growth, causing them to increase in size and length. Eventually, the abdominal cavity becomes too small to contain them. These organs (liver, bladder, stomach, intestines, spleen, ovaries, and testicles) subsequently extend into the umbilical cord. By the eleventh week of pregnancy, the abdominal cavity has expanded sufficiently to accommodate the intestines and liver, causing these organs to return to the abdominal cavity naturally. Omphalocele is the term used to describe the condition when these organs cannot rotate and fail to retract into the abdominal cavity.

The etiology of omphalocele is generally unknown. Omphalocele may develop in infants as a result of genetic or chromosomal disorders. Omphalocele may result from hereditary elements and environmental variables, including the mother's prenatal condition. Throughout pregnancy, the mother's consumption of food, beverages, and medications may impact the fetus.

Risk Factor

The specific etiology of omphalocele is unknown, although various factors may increase the baby's risk:

• The mother's age is either too young (under 20 years old) or too old (over 40 years old), causing risky pregnancy
• Omphalocele is more common in babies of alcoholic and smoker moms
• Babies of moms consuming SSRI antidepressants like sertraline, sitalopram, esitalopram, or fluoxetine during pregnancy
• Babies of obese moms before or during pregnancy
• Family history of omphalocele
• African race
• Baby boy
• Twin pregnancy

Symptoms

The detection of an omphalocele in a neonate is possible through ultrasound imaging, also known as ultrasonography. In the case of newborns, the omphalocele is easily identifiable in the midline of the abdominal cavity. The size of an omphalocele is proportional to the amount of organ protrusion, specifically:

• Small size: if only a portion of the intestine protrudes
• Large size: if it contains multiple abdominal organ
• Very large size: if it measures 5 cm or bigger and is accompanied by the protrusion of the liver

Diagnosis

Omphalocele could be diagnosed prenatally or postnatally. Throughout pregnancy, several screening procedures, or prenatal screenings, are performed to detect congenital abnormalities and other diseases. An omphalocele in a fetus may manifest abnormal findings upon examination, such as:

• Elevated alpha-fetoprotein (AFP) levels were detected in the mother's blood during the blood tests
• An ultrasound examination (USG) conducted after the initial trimester can also detect the existence of an omphalocele

If an omphalocele is identified during pregnancy, further examinations should be conducted, including:

• Echocardiography of the fetal heart
• Amniocentesis is performed to detect genetic abnormalities commonly associated with omphalocele and additional tests as recommended by the doctor

Following delivery, the presence of an omphalocele is identifiable through visual observation as organs protrude from the abdominal cavity and are encased by a protective sac or membrane. The presence of this membrane differentiates it from other disorders, specifically gastroschisis, which involves the inadequate development of the stomach wall, resulting in the expulsion of organs. Gastroschisis is characterized by the absence of a protective membrane around the organ, and the organ's position is typically shifted to the left of the midline of the abdominal cavity.

Management

Typically, when a baby is delivered with an omphalocele, the following stage is to immediately cover the protruding organ with a sterile dressing or a clean cloth. This maintains the infant's body temperature and prevents the loss of fluids. Avoid using excessively thick fabric to cover up organs. Surgery is the recommended treatment for infants with omphalocele, and the decision to proceed is based on a thorough consideration of the following factors:

• The size of the omphalocele

If the omphalocele is of small size or if only a fraction of the intestine protrudes outside the abdominal cavity, it is typically feasible to perform the surgical operation within 72 hours following the birth of the infant. The objective of the surgical treatment is to reposition the intestine within the abdominal cavity and seal the opening through which the intestine protrudes from the stomach.

Nevertheless, in cases where the omphalocele is extremely large or when numerous organs are located outside the stomach, the surgical procedure is typically conducted in several days to several weeks. The external organs will be covered with a specialized covering and gradually placed individually. The orifice through which the organs escape will be covered once all the organs are within the stomach.

The surgical process is performed in stages to ensure the newborn's safety. The abdominal cavity of an infant with an omphalocele is significantly reduced in size and unable to adequately accommodate all the organs simultaneously during development. The organ that is compelled to be inserted will not receive adequate circulation.

• Congenital birth defects or other chromosomal abnormalities that are present
• The gestational age of the mother at the time of delivery

Complications

Omphalocele complications may manifest during delivery, precisely when the peritoneal layer enveloping the organ ruptures. If the omphalocele is extremely large and the liver is exposed, the liver may sustain injury during delivery.

Following the delivery procedure, complications may still develop. Omphalocele is a condition where the organs that are supposed to be located inside the stomach are located outside. This condition leads to many complications in affected babies, including:

• The absence of organs within the abdominal cavity may result in its inability to grow to its standard size
• Infection can be a significant problem, particularly when the sac enveloping the organ is exposed or damaged
• Occasionally, these organs may experience compression or torsion, particularly the intestines, leading to reduced circulation to these organs. Disruption in blood circulation can lead to gradual harm to vital organs
• Impaired pulmonary growth

According to research, 23% of infants with large omphaloceles experienced mortality, with serious infections being the primary cause of death. Infection is more probable when the omphalocele sac is open.

Prevention

There are multiple strategies for preventing the occurrence of omphalocele. This is typically accomplished to preserve the mother's health, particularly during pregnancy. Pregnant women are required to undergo routine prenatal examinations. It is advisable to stop smoking and alcohol consumption and to maintain an ideal body weight consistently.

When to see a doctor?

Infants diagnosed with ophthalmoscope should be promptly referred to a healthcare center for adequate treatment and a comprehensive evaluation for potentially related disorders.

Once the baby is discharged, remain cautious for indications that necessitate a follow-up visit to the doctor, such as:

• Decreased frequency of defecation
• Eating disorder
• Fever
• Greenish vomiting
• Abdominal distension
• Behavioral changes of the infant