Type II Ileal Atresia in a Premature Low Birth Weight Neonate Mimicking an Intra-abdominal Mass: A Case Report

Abstract

Background: Jejunoileal atresia is a common cause of neonatal intestinal obstruction, with type II atresia accounting for approximately 10–15% of cases. However, atypical presentations may obscure early diagnosis, particularly in premature and low birth weight neonates. Type II ileal atresia is uncommon and may present with nonclassical clinical and radiologic features, leading to diagnostic delay and increased morbidity. Case Presentation: We report a premature low birth weight neonate who presented with recurrent bilious vomiting, abdominal distension, and a palpable right-sided abdominal mass shortly after birth. Initial imaging demonstrated a homogeneous right-sided intra-abdominal opacity with displacement of bowel loops, raising suspicion of an intra-abdominal mass rather than intestinal obstruction. The clinical course was further complicated by severe neonatal anemia and associated congenital anomalies, including congenital talipes equinovarus and hydronephrosis, which contributed to the diagnostic complexity of the case. Despite supportive management, symptoms persisted, prompting exploratory laparotomy. Intraoperatively, a type II ileal atresia was identified, characterized by blind-ending bowel segments connected by a fibrous cord with preserved mesentery. Resection of the atretic segment and primary ileoileal anastomosis were performed. The postoperative course was uneventful, and the patient achieved good feeding tolerance and clinical recovery. Conclusion: This case highlights a rare diagnostic pitfall in which type II ileal atresia mimicked an intra-abdominal mass. Awareness of such atypical presentations and early surgical consultation are essential to avoid delays in diagnosis and to optimize outcomes in high-risk neonatal populations.