Jejunoileal atresia

Congenital obstruction of the small intestine (jejunum or ileum) due to an in‑utero vascular accident causing a blind-ending or missing segment of bowel; a common cause of neonatal bilious vomiting.

• Accounts for ~40% of all intestinal atresias and is a surgical emergency in newborns. Early recognition (e.g., bilious emesis on day 1) is critical to prevent dehydration, perforation, or short gut complications. Classic imaging (the triple bubble sign) and contrasts with duodenal atresia (double bubble, Down syndrome) make it a high-yield exam topic.

• Newborn (often Day 1–2 of life) with bilious vomiting after feeds, varying abdominal distension (minimal if proximal atresia, pronounced if distal). Prenatal ultrasound may show polyhydramnios and dilated bowel loops. Meconium passage may be delayed (not in first 24 hours), though passing a small amount of meconium does not exclude atresia.
• Abdominal X-ray reveals multiple dilated loops: classically a triple bubble (dilated stomach, duodenum, proximal jejunum) with no gas in the rest of the intestines. More distal atresias show numerous air–fluid levels (low obstruction pattern). A contrast enema often shows a microcolon (unused, tiny colon) distal to the blockage.
• Caused by an intrauterine vascular insult (e.g., fetal volvulus, intussusception, or arterial thrombus) leading to bowel infarction. Maternal risk factors include cocaine or tobacco use (vasoconstrictors). Often isolated, but can be associated with gastroschisis, malrotation, or cystic fibrosis (due to meconium ileus).

1. Treat any neonate with bilious emesis as an obstruction until proven otherwise: immediately keep NPO, place NG tube for decompression, and start IV fluids. Rapid evaluation is needed, as midgut volvulus presents similarly but can quickly cause ischemia.
2. Obtain an abdominal X-ray to identify the obstruction level. Double bubble (two dilated structures) suggests duodenal atresia (often with Down syndrome), whereas triple bubble indicates jejunal atresia. Numerous dilated loops with no gas beyond signal distal obstruction (ileal atresia vs. meconium ileus).
3. Use a contrast enema study to distinguish atresia from meconium ileus and to check for multiple lesions. A microcolon on enema implies distal small-bowel obstruction (ileal atresia or meconium ileus). If contrast passes through to normal-caliber distal bowel, atresia is less likely.
4. During surgery, the entire bowel must be inspected for multiple atretic segments (e.g., string-of-sausages or apple-peel configuration). Postoperatively, monitor for short bowel syndrome if extensive resection was required.

1. Stabilize first: NPO, NG tube to continuous suction, IV fluid resuscitation, and correct electrolytes. Add broad-spectrum IV antibiotics if perforation or peritonitis is suspected.
2. Prompt surgical repair is definitive: resection of the atretic segment(s) followed by end-to-end anastomosis of healthy bowel. If there's concern about bowel viability or a huge length disparity, a temporary ostomy may be placed.
3. After surgery, provide parenteral nutrition (TPN) until the infant can tolerate enteral feeding. Gradually introduce oral feeds as bowel function returns. If a substantial length of intestine was removed (multiple atresias), watch for short bowel syndrome (malabsorption requiring prolonged nutrition support).

• Think triple = jejunal: a "triple bubble" on neonatal X-ray is classically jejunal atresia (vs. double bubble for duodenal atresia in Down syndrome).
• Exam clues like a mother using cocaine or an infant with gastroschisis point to jejunoileal atresia from in‑utero vascular injury.
• Apple-peel atresia refers to multiple atresias (Type IIIb) with the remaining intestine coiled around a single artery, resembling an apple peel.

• Any green (bilious) vomit in a neonate is an emergency warning sign—assume intestinal obstruction (atresia or midgut volvulus) until proven otherwise.
• Signs of intestinal perforation or ischemia (tense, discolored abdomen, shock, or peritonitis) → urgent surgical intervention is required.

1. Prenatal: if polyhydramnios and dilated bowel loops are seen on ultrasound, suspect possible intestinal atresia.
2. Neonate with bilious emesis → immediately NPO, NG tube for decompression, and IV fluids; obtain an abdominal X-ray.
3. If X-ray shows double bubble, manage as duodenal atresia; if triple bubble or multiple dilated loops with no distal gas, suspect jejunoileal atresia (versus other distal obstruction). Consider an upper GI contrast study if malrotation/volvulus is a concern.
4. Do a contrast enema to differentiate distal atresia from meconium ileus and to check for additional atresias. A microcolon on enema supports distal obstruction, whereas passage of contrast to normal colon suggests an alternate diagnosis.
5. Surgical management: perform exploratory laparotomy, resect the atretic segment(s), and primary anastomosis. Inspect the entire bowel for multiple atresias. Postoperatively, support with TPN and gradual feeds; arrange follow-up for nutrition and growth (short bowel risk).

• Term neonate with projectile bilious vomiting in the first day of life and abdominal X-ray showing three air-filled levels (stomach, duodenum, jejunum) with no gas distally → Jejunal atresia.
• Newborn with an abdominal wall defect (gastroschisis) who, after initial repair, has persistent obstruction and multiple dilated bowel loops on imaging → Jejunoileal atresia due to compromised blood supply (common in gastroschisis).