Definition:
Duodenal atresia is a condition in which the duodenum (the first part of the small bowel) has not developed properly. It is not open and cannot allow the passage of stomach contents.
Causes, incidence, and risk factors:
The cause of duodenal atresia is unknown, but it is thought to result from problems during the developmental stage in which the embryo's 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.
Symptoms:
- 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
Signs and tests:
- 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
- An 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 those related to Downs syndrome) must be treated as appropriate.
Expectations (prognosis):
Recovery from the duodenal atresia is expected after treatment. Untreated, the condition is fatal.
Complications:
- Associated congenital anomalies
- Dehydration
- After surgery, there may be late complications such as duodenal swelling (megaduodenum), intestinal motility problems, or gastroesophageal reflux.
