Epidemiology and Etiology
Epidemiology
- Overall incidence: 2.5–10 per 100,000 live births
- Duodenal atresia:
- Incidence: 1 in 10,000 live births
- 50% of infants with duodenal atresia are premature.
- Common concomitant anomalies:
- Down’s syndrome (25%–40%)
- Congenital heart disease (30%): associated with increased mortality
- Annular pancreas (30%): associated with late pancreatitis, gastroesophageal reflux disease, peptic ulcer disease, and gastric cancer
- Malrotation (20%–30%)
- Renal anomalies (5%–15%)
- Esophageal atresia (5%–10%)
- Skeletal malformations (5%)
- Anorectal anomalies (5%)
- Annular pancreas:
- Incidence: 5–15 per 100,000 adults
- Common concomitant abnormalities:
- Maternal polyhydramnios
- Meckel’s diverticulum
- Down’s syndrome
- Imperforate anus
- Duodenal atresia
- Esophageal atresia
- Duplication cysts:
- Incidence: 1 in 45,000 births
- Duodenal duplication cysts make up only 5% of reported cases.
- Congenital bands: Incidence of duodenal obstruction due to Ladd’s bands is not reported.
Etiology
- Intrinsic (most common):
- Duodenal atresia (most common): failed recanalization of the duodenum during embryonal development
- Duodenal stenosis: incomplete recanalization of the duodenum during embryonal development
- Extrinsic:
- Annular pancreas: band of pancreatic tissue surrounding the duodenum arising from incorrect rotation of the pancreatic bud during embryonal development
- Congenital bands (Ladd’s bands): fibrous bands of peritoneum that persist due to malrotation of the small intestines
- Duplication cyst: cystic malformations of the small intestines that can deform the lumen of the duodenum
- Intrinsic and extrinsic causes may occur concomitantly.
Annular pancreas with a band of pancreatic tissue surrounding the duodenum leading to obstruction caused by a malrotation of the pancreatic bud during development
Image by Lecturio.
Anatomical comparison between a healthy small intestine and duodenal atresia.
Image by Lecturio.
Duodenal atresia is caused by the failure of the duodenum to recanalize during embryonal development.
Ladd’s bands in a patient with malrotation.
Image by Lecturio.
The bands of fibrous peritoneal tissue can put pressure on and obstruct the duodenum.
Clinical Presentation
Signs and symptoms of intestinal obstruction:
- Polyhydramnios and bile-stained amniotic fluid may be present at birth.
- Bilious vomiting without abdominal distension on 1st day of life (hallmark)
- Delayed symptoms or prolonged vomiting and failure to thrive based on severity of occlusion
- Abdominal peristaltic waves may be present, especially early in the course.
Associated abnormalities:
- Biliary atresia
- Agenesis of gallbladder
- Renal, limb, and vertebral malformations
Diagnosis and Management
Diagnosis
History
- Prenatal:
- Duodenal obstruction in other pregnancy
- Bowel dilatation or polyhydramnios on prenatal screening
- Maternal diabetes mellitus
- Perinatal:
- Gestational age
- Hours from birth to onset of vomiting
- Timing of meconium passing
- Family history:
- Siblings with intestinal malformations
- Cystic fibrosis
Physical exam
- General:
- Signs pointing to dehydration
- Dysmorphic features suggestive of associated abnormalities seen with atresia (e.g., Down’s syndrome)
- Skin: jaundice
- Abdomen: Distension suggests that obstruction is not duodenal but more distal.
- Rectal exam: anal atresia associated with duodenal atresia
Imaging
- Prenatal ultrasound:
- Shows “double bubble” sign (air-filled stomach and duodenum)
- May reveal polyhydramnios
- Radiography:
- Double bubble sign confirms diagnosis of duodenal obstruction.
- Contrast studies may occasionally be needed to rule out malrotation and volvulus.
- Computed tomography (CT) or magnetic resonance imaging (MRI) may be used for better visualization.
Prenatal ultrasound showing fetal double bubble sign with polyhydramnios
Image: “Congenital Duodenal Obstruction in Neonates” by Journal of Neonatal Surgery. License: CC BY 3.0
Double bubble sign in a patient with duodenal atresia
Image: “Alimentary Tract Atresias associated with Anorectal Malformations” by Journal of Neonatal Surgery. License: CC BY 3.0
Management
Medical therapy
- Nasogastric decompression
- Fluid resuscitation
Surgical management
- Duodenal atresia and/or annular pancreas are corrected with duodenoduodenostomy.
- Long-term prognosis is excellent.
References
- Kliegman RB, ST Geme JW, Blum MJ, Shah SS, Tasker RC, Wilson KM, Behrman RE. (2016). In Nelson’s Textbook of Pediatrics. (20th ed.) Elsevier.
- Ravitch MM. (1975). The pancreas in infants and children. Surg Clin North Am, 55(2):377–85. https://doi.org/10.1016/s0039-6109(16)40587-6
- Sangüesa Nebot C, Llorens Salvador R, Carazo Palacios E, Picó Aliaga S, Ibañez Pradas V. (2018). Enteric duplication cysts in children: varied presentations, varied imaging findings. Insights Imaging, 9(6):1097–1106. https://doi.org/10.1007/s13244-018-0660-z
- Sadler TW, Langman J. (2012). Langman’s medical embryology (12th ed.) Wolters Kluwer Health/Lippincott Williams & Wilkins.
