Neonatal Low Bowel Obstruction Differential Diagnosis

Today's Daily Diff concerns low or large bowel obstruction in the neonate. The clinical differential diagnosis of a neonate with low intestinal obstruction is anorectal malformations, Hirschsprung disease, meconium ileus, functional immaturity of the colon, and distal intestinal atresia. To keep the diagnoses in mind, just remember HAMM:

	Disease	Notes
H	Hirschsprung disease	most common cause caused by lack of ganglion cells in distal colon/rectum colon dilates over time
A	Atresia (anal; distal intestinal)	can be part of VACTERL syndrome often there is fistula between distal bowel and bladder or perineum
M	Meconium ileus	associated with cystic fibrosis meconium abnormal
M	Meconium plug syndrome	aka small left bowel syndrome transient; meconium normal

While other entities can also cause bowel obstruction, the ones listed above cover the majority of the causes. In preterm babies, necrotizing enterocolitis is a major consideration. In an older population, the differential changes for bowel obstruction in children.