Intestinal Atresia and Stenosis

On this page

Intestinal Atresia/Stenosis - Embryo's Oopsie Daisy

  • Definitions:
    • Atresia: Complete congenital obstruction of intestinal lumen; a gap.
    • Stenosis: Incomplete obstruction or narrowing of intestinal lumen.
  • Incidence: Affects ~1 in 1500-5000 live births.
  • General Embryological Basis:
    • Failure of recanalization: Fetal gut's solid cord stage (Weeks 8-10) fails to re-open.
    • Vascular accidents: Intrauterine ischemic events cause bowel segment resorption. Types of Intestinal Atresia

⭐ Intestinal atresia is the most common cause of congenital intestinal obstruction in newborns.

Duodenal Atresia - Double Bubble Classic

  • Embryology: Failure of recanalization of duodenum (typically 8th-10th week gestation).
  • Clinical Features:
    • Bilious vomiting (85%) within hours of birth.
    • Epigastric fullness/distension.
    • Polyhydramnios in utero (50%).
  • Associations:
    • Down syndrome (Trisomy 21) (~30%).
    • 📌 VACTERL (Vertebral, Anal, Cardiac, Tracheo-Esophageal, Renal, Limb defects).
    • Annular pancreas, malrotation.
  • Diagnosis:
    • X-ray: Classic "double bubble" sign (stomach and proximal duodenum).
    • Absence of distal gas (indicates complete obstruction). X-ray: Double bubble sign in duodenal atresia

⭐ Approximately 30% of infants with duodenal atresia have Down syndrome (Trisomy 21).

Jejunoileal & Colonic Atresia - Vascular Event Aftermath

  • Etiology: In-utero mesenteric vascular accident (ischemic insult) → bowel necrosis & resorption.

    ⭐ Jejunoileal atresias are most commonly caused by an in-utero mesenteric vascular accident.

  • Jejunoileal (JI) Atresia Classification (Louw & Barnard):
    TypeDescription
    IMembranous web
    IIFibrous cord between blind ends
    IIIaMesenteric gap, V-shaped
    IIIbApple-peel/Christmas tree deformity
    IVMultiple atresias (string of sausages)
    Louw & Barnard Classification of Jejunoileal Atresia
  • Clinical: Bilious vomiting (first 24-48h), abdominal distension, failure to pass meconium.
  • Diagnosis:
    • X-ray: Multiple air-fluid levels, no distal gas.
    • Contrast enema: Microcolon; rules out colonic atresia/meconium ileus.
  • Colonic Atresia: Rarer; similar etiology; types (membranous, cord, separation).

Diagnosis & Management - Spot & Snip Strategy

  • Antenatal Diagnosis: Ultrasound showing polyhydramnios.

    ⭐ Polyhydramnios is a significant antenatal indicator, especially for proximal intestinal atresias like duodenal atresia.

  • Postnatal Diagnosis:
    • Plain abdominal X-ray (e.g., "double bubble" sign).
    • Upper GI contrast study if needed; contrast enema for distal obstruction.
  • Preoperative Stabilization: NPO, nasogastric/orogastric tube decompression, IV fluids, electrolyte correction, prophylactic antibiotics.
  • Surgical Principles:
    • Resection of dilated proximal bowel, primary end-to-end anastomosis.
    • Tapering enteroplasty for significant caliber discrepancy.
    • Stoma creation if primary anastomosis is unsafe.
  • Postoperative Complications: Anastomotic leak, stricture formation, short bowel syndrome.

High‑Yield Points - ⚡ Biggest Takeaways

  • Duodenal atresia is strongly associated with Down syndrome and presents with a classic "double bubble" sign on X-ray.
  • Jejunoileal atresias typically result from in-utero vascular accidents or ischemic insults.
  • The "apple peel" or "Christmas tree" deformity is characteristic of Type IIIb jejunal atresia.
  • Bilious vomiting shortly after birth is a cardinal sign of intestinal obstruction distal to the ampulla of Vater.
  • Maternal polyhydramnios is a common antenatal finding, especially with proximal intestinal atresias.
  • Intestinal stenosis causes incomplete obstruction, often presenting with more subtle or delayed symptoms than atresia.
  • Definitive management for all intestinal atresias and symptomatic stenosis is surgical repair.
Rezzy AI Tutor

Have doubts about this lesson?

Ask Rezzy, our AI tutor, to explain anything you didn't understand

Practice Questions: Intestinal Atresia and Stenosis

Test your understanding with these related questions

X-ray feature of pyloric stenosis is –

1 of 5

Flashcards: Intestinal Atresia and Stenosis

1/9

_____ is characterized by dilation of the stomach and proximal duodenum with a "double bubble" sign on X-ray

TAP TO REVEAL ANSWER

_____ is characterized by dilation of the stomach and proximal duodenum with a "double bubble" sign on X-ray

Duodenal atresia

browseSpaceflip

Enjoying this lesson?

Get full access to all lessons, practice questions, and more.

Start For Free