- Clinical science
Duodenal atresia and stenosis
Abstract
Duodenal atresia is a complete occlusion or absence of the duodenal lumen, whereas duodenal stenosis refers to an incomplete obstruction caused by narrowing. Both conditions present with signs of obstruction, including a distended upper abdomen, delayed meconium passage, and vomiting. If the defect is located proximal to the major duodenal papilla, nonbilious vomiting occurs, whereas a defect occurring distal to the papilla causes bilious vomiting. Evidence of polyhydramnios on prenatal ultrasonography may lead to an early diagnosis of duodenal obstruction. An abdominal x-ray typically shows the double bubble sign. Duodenal atresia and stenosis generally have a favorable prognosis and may be surgically treated through duodenoduodenostomy.
Epidemiology
- Around 1/5000–10,000 live births
- ∼ 50% of cases are associated with further anomalies, e.g., bile duct and VACTERL association.
- 30% of cases are associated with chromosomal abnormalities, especially Down syndrome.
References:[1][2]
Epidemiological data refers to the US, unless otherwise specified.
Pathophysiology
Duodenal atresia occurs when recanalization of the closed duodenum fails to occur or occurs only partially during the embryonic period (usually between the 8th–10th week of gestation). Because the development of the duodenum is connected to the growth of the pancreas and the hepatobiliary system, duodenal atresia is commonly associated with anomalies of these organs as well.
References:[1]
Clinical features
Intrauterine
Postpartum
-
Vomiting, that is typically bilious if the stenosis is distal to the major duodenal papilla
- Atresia or high-grade stenosis: vomiting few hours after birth
- Mild stenosis: vomiting after a few days
- Distended upper abdomen and scaphoid lower abdomen
- Delayed meconium passage
References:[3][1]
Diagnostics
Prenatal
-
Ultrasound
- Polyhydramnios
- Dilation of the stomach and duodenum (proximal to the obstruction) is common.
- Double bubble sign
Postnatal
-
X-ray of the abdomen
- Double bubble sign
- Gasless distal bowel
- Associated anomalies may also be investigated with the following methods:
- Physical examination
- Ultrasound of the abdomen and kidneys
- Echocardiography
- X-ray of the thorax
- X-ray, ultrasound, and/or MRI of the spine
References:[4][3]
Differential diagnoses
Jejunal atresia
- Definition: absence of the jejunal lumen
- Epidemiology: less common than duodenal atresia
- Pathophysiology
-
Clinical features: similar to duodenal atresia
- Polyhydramnios (intrauterine)
- Bilious vomiting and upper abdominal distension (postpartum)
- Diagnosis: abdominal x-ray shows a triple bubble sign and gasless colon
- Treatment: surgical correction with bypass of the occluded part of bowel is always required
The differential diagnoses listed here are not exhaustive.
Treatment
-
Preoperative management
- Parenteral nutrition via a central catheter shortly after birth
- Fluid replacement and restoration of the electrolyte balance
- Gastric decompression
-
Surgery: bypass the atresia or stenosis
- The exact procedure depends on the anatomic findings and associated anomalies
- Common procedure: duodenoduodenostomy or duodenojejunostomy with a proximal transverse-to-distal longitudinal (diamond-shaped) anastomosis
References:[5]
Prognosis
- If diagnosis and treatment occur quickly, the survival rate of isolated duodenal atresia (without further anomalies) is 95%.
- The presence of other anomalies worsens the prognosis.
References:[2]