Atresia of the Transverse Colon (Grosfeld Type IIIa) Diagnosed at Seven Days of Life: A Case Report.

Colonic atresia is a rare cause of neonatal intestinal obstruction, and involvement of the transverse colon is particularly uncommon. We report a seven-day-old term male neonate with failure to pass meconium since birth, bilious vomiting, abdominal distension, and jaundice. Plain abdominal radiography demonstrated diffuse bowel-loop dilatation with relative paucity of distal gas. Exploratory laparotomy revealed atresia of the transverse colon (Grosfeld type IIIa), with a markedly dilated proximal colon, an atrophic distal colon, and a V-shaped mesenteric defect. A right hemicolectomy was performed, followed by a hand-sewn end-to-end anastomosis between the terminal ileum and the descending colon. During the postoperative course, late-onset neonatal sepsis was diagnosed, with Enterobacter cloacae detected by a molecular sepsis panel despite negative conventional blood cultures. The patient was successfully treated with cefepime, without anastomotic or intra-abdominal complications. Enteral feeding was progressively introduced, and the patient achieved full tolerance of breastfeeding and was discharged in good condition. This case emphasizes the importance of considering colonic atresia in neonates with persistent distal intestinal obstruction and illustrates that primary anastomosis may be feasible in selected patients when distal bowel patency and the clinical condition are favorable.