Duodenal atresia

Atresia

Atresia is a condition in which a body orifice or passage in the body is abnormally closed or absent.Examples of atresia include:* Imperforate anus - malformation of the opening between the rectum and anus....

is the congenital absence or complete closure of a portion of the lumen

Lumen (anatomy)

A lumen in biology is the inside space of a tubular structure, such as an artery or intestine...

 of the duodenum

Duodenum

The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear and the terms anterior intestine or proximal intestine may be used instead of duodenum...

.

Associated conditions

Approximately 20–40% of all infants with duodenal atresia have Down syndrome

Down syndrome

Down syndrome, or Down's syndrome, trisomy 21, is a chromosomal condition caused by the presence of all or part of an extra 21st chromosome. It is named after John Langdon Down, the British physician who described the syndrome in 1866. The condition was clinically described earlier in the 19th...

. . Approximately 8% all infants with Down syndrome have duodenal atresia.

It is also associated with polyhydramnios

Polyhydramnios

Polyhydramnios is a medical condition describing an excess of amniotic fluid in the amniotic sac. It is seen in 0.2 to 1.6% of pregnancies,,...

, which is increased amniotic fluid

Amniotic fluid

Amniotic fluid or liquor amnii is the nourishing and protecting liquid contained by the amniotic sac of a pregnant woman.- Development of amniotic fluid :...

 in the uterus.

Diagnosis

The diagnosis of duodenal atresia is usually confirmed by radiography

Radiography

Radiography is the use of X-rays to view a non-uniformly composed material such as the human body. By using the physical properties of the ray an image can be developed which displays areas of different density and composition....

. An X-ray

X-ray

X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...

of the abdomen shows two large air filled spaces, the so-called "double bubble" sign. The air is trapped in the stomach and proximal duodenum. Since the closure of the duodenum is complete in duodenal atresia, no air is seen in the distal duodenum.

Atresias distal to the duodenum are usually caused by vascular accidents or ischemic insult, such as jejunoileal atresia.