Enteric duplication cyst as a lead point for intrauterine segmental volvulus resulting in type IIIa ileal atresia: a neonatal case report and focused literature review.

BACKGROUND: Jejunoileal atresia is most commonly attributed to intrauterine mesenteric vascular accidents. Both segmental volvulus and enteric duplication cysts are recognized yet uncommon causes of fetal vascular compromise capable of inducing intestinal ischemia. The simultaneous occurrence of ileal atresia, segmental volvulus, and enteric duplication cyst in a single neonate is exceedingly rare and offers valuable insight into the vascular pathogenesis of intestinal atresia. CASE PRESENTATION: We report the case of a male term neonate admitted eleven hours after birth for bilious vomiting and progressive abdominal distension. Plain abdominal radiography revealed multiple air-fluid levels, and contrast enema demonstrated a microcolon with characteristic "string-of-beads" filling defects in the distal ileum consistent with meconium pellets. Exploratory laparotomy identified a type IIIa distal ileal atresia located 20 cm from the ileocecal valve, associated with a segmental volvulus twisting around a 3 cm cystic enteric duplication. The volvulated bowel segment, duplication cyst, and dilated proximal ileum were resected, and a primary end-to-end ileoileal anastomosis was performed. Histopathology confirmed cystic ileal duplication with bilateral ileal atresia at the resection margins. Despite an initially stable postoperative course, the infant developed severe bronchiolitis with respiratory failure and died on postoperative day 10. CONCLUSION: This rare neonatal triad supports the hypothesis that enteric duplication cysts may act as intrauterine lead points for segmental volvulus, triggering mesenteric vascular compromise and secondary ileal atresia. Any neonate presenting with distal bowel obstruction and microcolon should prompt consideration of complex intrauterine vascular events. Prompt surgical exploration remains essential to maximize intestinal preservation and improve outcomes.