How is duodenal atresia diagnosed?
How is duodenal atresia diagnosed?
Healthcare providers may detect duodenal atresia before or after birth.
Prenatally, providers may detect potential duodenal atresia using the following:
- Fetal ultrasounds: These tests can examine your baby’s digestive tract. The presence of two “bubbles” representing the stomach and duodenum or just a large stomach bubble will raise concern for duodenal atresia or stenosis. The ultrasound may also show high levels of amniotic fluid (polyhydramnios). Typically, babies swallow and absorb some amniotic fluid in the womb. But a baby with duodenal atresia or stenosis may not swallow and absorb amniotic fluid in normal amounts. This can result in excess amniotic fluid around the baby.
- Fetal magnetic resonance imaging (MRI): This imaging test may show some similar findings to ultrasound, but it can be helpful in determining the level of the atresia if it is not clear on ultrasound.
If duodenal atresia is suspected or diagnosed prenatally, it becomes important to look for chromosomal defects, such as those associated with Down syndrome. This can be done with amniocentesis or chorionic villus sampling.
- Amniocentesis: This is a test to check for genetic or chromosomal conditions, such as Down syndrome. The procedure involves analyzing a small sample of your amniotic fluid.
Even if providers suspect duodenal atresia before birth, they cannot verify the diagnosis until the baby is born. After your baby’s birth, healthcare providers may use:
- Abdominal X-rays: This test looks for air or fluid in the stomach and first part of the intestine. Classically, for duodenal atresia, one will see an enlarged (dilated) stomach and duodenum without air further along in the intestines. This is called the “double-bubble” sign. For duodenal stenosis, partial duodenal obstruction or duodenal atresia with a rare bile duct malformation, air may still be seen in the intestines beyond the duodenum.
- Barium swallow tests: This test uses a safe amount of barium (white liquid that shows up on X-rays) and fluoroscopy (using real-time X-rays to create a movie). Providers use this test to examine the upper gastrointestinal (GI) tract. Babies usually receive the barium through a nasogastric tube (tube that runs through the nose to the upper GI tract). This test is most useful to define partial duodenal obstructions or stenosis and to look for other causes of symptoms in the absence of a clear diagnosis of duodenal atresia.