Duodenal Duplication Cyst: A Rare Differential Diagnosis in a Neonate with Bilious Vomiting.

Bilious vomiting is a relevant sign in neonates that requires immediate evaluation and diagnosis. A duplication of the intestinal tract is a possible cause of obstruction if located distally to the major duodenal papilla of Vater and most of them involve the jejunum, stomach, or colon. Duodenal duplications are very rare and can have an endoscopic or surgical treatment after diagnosis. We present a case of a 16-day-old term newborn that consulted because of bilious vomiting and after evaluation with imaging and upper endoscopy, a duodenal duplication cyst was found at the level of the third portion causing compression of the intestinal lumen that required surgical resolution with duodenocystostomy.