The cause of duodenal atresia is unknown, but it is thought to result from problems during the embryologic stage in which the duodenum normally changes from solid to tube-like (recanalization).

Duodenal atresia is present in more than 1 in 10,000 live births. Approximately 20-30% of infants with duodenal atresia have Downs syndrome. Duodenal atresia is often associated with other congenital abnormalities.

• Upper abdominal swelling may or may not be present
• Early vomiting of large amounts, which may be greenish (containing bile)
• Continued vomiting even when infant has not been fed for several hours
• Absent urination after first few voidings
• Absent bowel movements after first few meconium stools

• This condition may be suggested by fetal ultrasound showing polyhydramnios (excessive amounts of amniotic fluid in the uterus) or swelling of the stomach and part of the duodenum
• A plain abdominal x-ray may show air in the stomach and first part of duodenum, with no air beyond that
• An abdominal x-ray with contrast may be helpful

A tube is placed to decompress the stomach. Dehydration and electrolyte abnormalities are corrected by providing fluids through an intravenous tube. An evaluation for other congenital anomalies should be performed.

Surgery to correct the duodenal blockage is necessary, but is not an emergency. The surgical approach will depend on the nature of the abnormality. Associated problems (such as Downs syndrome) must be treated as appropriate.

• Associated congenital anomalies
• Dehydration
• After surgery, there may be late complications such as duodenal swelling (megaduodenum), intestinal motility problems, or gastroesophageal reflux.

There is no known prevention.