- abnormal innervation of the bowel
beginning at the anus and extending proximally; Absence of intramural ganglion
rectum and variable distance proximally
- Functional distal bowel obstruction
- Present with delayed passage of meconium, emesis, abdomenal distention and
colitis in infants
- Affected infants often fail to pass
meconium within the first 48 hours of life, but rarely do they develop
symptoms of small intestinal obstruction during this period.
- Later presents as chronic constipation, rectal exam reveals increased tone
with empty rectal vault
- The disorder can usually be diagnosed by
barium enema if a "transition zone" in which a funnel-shaped area of intestine
has a proximal dilation (normally innervated) and
distal narrowing is visualized.
Note: do not prep the bowel beforehand, as this "erases" the transition zone
- Often the rectum is larger than the
- Failure to pass the barium on a delayed
film 24 hours later is suggestive of Hirschsprung disease, even in the absence
of a transition zone.
dx is rectal biopsy
- Rx: colostomy then pull through
Associated with Waardenburg Syndrome