Answer: Hirschsprung disease
Barium enema images demonstrate a reduced caliber rectum (the rectum is smaller than the sigmoid and descending colon). A transition point is seen at the sigmoid colon.
Hirschsprung disease is the most common cause of neonatal colonic obstruction. It is commonly characterized by a short segment of colonic aganglionosis affecting term neonates.
1.Swenson O. Hirschsprung’s disease: a review. Pediatrics. 2002;109 (5): 914-8.