Duodenal Atresia - Types, Symptoms, Diagnosis & Treatment

The duodenum is the first part of the small intestine. It receives partially digested food from the stomach and digestive juices from the liver and pancreas, helping digestion.

In duodenal atresia, part of the duodenum is completely blocked, preventing intestinal contents from passing normally. It is present at birth and differs from acquired causes of intestinal obstruction that develop after birth. Duodenal stenosis differs because the passage is narrowed but not completely closed. The condition may occur alone or alongside other congenital abnormalities, including chromosomal conditions and abnormalities affecting the heart, kidneys or digestive system.

Duodenal Atresia Causes

The exact cause is not always known. During early development, the duodenum temporarily becomes solid before developing an open passage. If this process, called recanalisation, does not occur properly, a blockage may remain.

Recognised factors associated with duodenal atresia include:

• Abnormal intestinal development: The duodenum fails to form a normal open passage.
• Chromosomal conditions: The condition is associated with Down syndrome, also known as trisomy 21.
• Other congenital abnormalities: Some babies also have heart defects or abnormalities affecting other organs.

The precise cause in an individual baby may remain unclear. It is not usually caused by anything parents knowingly did or failed to do during pregnancy, and no method guarantees prevention.

Duodenal Atresia Types

The types describe the anatomical structure of the blockage:

Atresia means the intestine is completely blocked, while stenosis means the intestine is narrowed. The location of the blockage affects the type of vomiting. If the blockage is below where bile enters the duodenum (the first part of the small intestine), the baby usually vomits green fluid (bilious vomiting). If the blockage is above this point, the vomit usually does not contain bile and is not green (non-bilious vomiting).

Duodenal Atresia Symptoms

Symptoms usually appear soon after birth, especially when feeding begins. They vary with the blockage's location and may include:

• Green or yellow-green vomiting, which may contain bile and requires urgent medical assessment.
• Feeding difficulties or repeated vomiting after feeds.
• Upper abdominal swelling as fluid accumulates in the stomach and upper intestine.
• Reduced stool passage, although early bowel movements can still occur.
• Possible dehydration, shown by reduced urination, unusual sleepiness or poor feeding.

Not every newborn has all these signs. Some babies are diagnosed before birth. Green vomiting, repeated vomiting, poor feeding or signs of dehydration require immediate medical assessment because they may indicate serious intestinal obstruction.

Duodenal Atresia Diagnosis

Diagnosis may occur during pregnancy or after birth. Doctors use imaging and clinical assessment to identify the blockage and check for associated abnormalities.

Before birth

Prenatal ultrasound may show an enlarged stomach and duodenum, creating a characteristic “double-bubble sign.” Excess amniotic fluid, called polyhydramnios, may also raise suspicion. Further specialist assessment may be needed if findings are uncertain.

After birth

Investigations may include:

• Abdominal X-ray: May show the double-bubble sign and little or no air beyond a complete blockage.
• Additional imaging: Ultrasound or a selected contrast study may clarify uncertain findings or rule out other obstructions.
• Blood tests: May assess dehydration and electrolyte imbalances.
• Associated-condition screening: Heart evaluation, genetic assessment or other tests may be recommended.

The tests selected depend on the baby's clinical findings.

Duodenal Atresia Treatment

Treatment aims to remove the blockage, maintain the baby’s fluid and nutritional balance, and support recovery. A team of newborn-care specialists and a paediatric surgeon will plan the treatment.

Initial stabilisation

• Before surgery, doctors take steps to keep the baby stable and prepare for treatment. These may include:
• Temporarily stopping feeding by mouth.
• Placing a thin tube through the nose or mouth into the stomach to remove trapped fluid and air.
• Giving fluids through a vein (intravenous or IV fluids) to treat dehydration and maintain the body's balance of salts and minerals.
• Checking the baby's vital signs and looking for other health conditions.

Surgical correction

Surgery is the main treatment for complete duodenal atresia. A procedure called duodenoduodenostomy is commonly performed to join the affected parts of the intestine, allowing food and fluids to pass through normally. The type and timing of surgery depend on the baby's condition and the structure of the blockage.

Recovery and feeding

After surgery, doctors monitor the baby's bowel function, recovery and ability to tolerate feeds. Feeding is usually restarted gradually when the medical team considers it safe. Some babies may need temporary nutritional support during recovery. The length of the hospital stay depends on the baby's progress and any other health conditions.

Possible Problems and Long-Term Recovery

Without treatment, duodenal atresia can lead to dehydration, an imbalance of salts and minerals in the body, and problems with nutrition.

After surgery, some babies may experience delayed stomach emptying, acid reflux, difficulty feeding or problems with normal bowel movements. If these problems continue, further medical evaluation may be needed.

Most babies have a good recovery outlook when the blockage is treated and any associated health conditions are managed. However, recovery can vary from one baby to another.

Regular follow-up appointments help doctors monitor the baby’s feeding, growth, nutrition and digestion. Parents should inform the healthcare team if their baby has ongoing vomiting, feeding difficulties or poor weight gain.

Conclusion

Duodenal atresia is a birth condition in which part of the small intestine is completely blocked, preventing food and fluids from passing through normally. It may be detected during pregnancy through ultrasound or identified after birth when symptoms such as vomiting and feeding difficulties appear.

Early diagnosis and appropriate treatment are important for the baby's recovery. Surgery, fluid management, nutritional support and regular follow-up help manage the condition. Early specialist care also helps identify other health conditions and supports the baby's growth and development.

Reader Information: The information provided in this article is intended for general educational and informational purposes only and should not be considered medical advice, diagnosis, or treatment. This condition may have different underlying causes and may require professional evaluation and care. Always consult a qualified healthcare professional for personalised advice regarding symptoms, diagnosis, or treatment options.