Peds 2002;109:914

Cause:In familial forms, inactivation mutation in REI proto-oncogene, like type II MEN (Nejm 1995;335:943)

Pathophys:Aganglionic segment of colon, variable in length from a few cm in rectum to all rectum and descending colon. No sympathetic neurons in this segment resulting in constant contractions and no relaxation, which is necessary for effective peristalsis, and this results in intestinal obstruction, acute (infants) or chronic (children and teenagers)

Usually in infants; male/female = 1:4; 1/5000 live births

Sx:No meconium in 1st 48 hours of life, abdominal pain, chronic constipation without the occasional “huge stools” typical of retentive encopresis

Damaged pelvic neural structures

r/o Chagas’ disease; chronic idiopathic intestinal obstruction (Nejm 1977;297:233)

Lab:

Path:Rectal bx aganglionic, but beware normally aganglionic 2-cm band around internal sphincter

Rx:

Surgical excision of affected segments or bypass that segment; most operated on in 1st weeks of life without need for colostomy