Hirschsprung Disease: Update Course 2013

False positive contrast enemas occur in newborns showing a transition zone that looks like Hirschsprung's but is not

There is an occasional patient really sick from enterocolitis where you may not want to wait for tissue diagnosis and might have to operate and divert because it's long segment, can't decompress with irrigation, and pathology won't be back for days

In Mana Proctor's paper, 8% of cases that looked like short transition zone had pathological transition zone significantly higher (long transition zone)

The incidence of long segment Hirschsprung's in girls is fifty-fifty, so odds are much higher than in boys

In older kids, if they have a normal recto-anal inhibitory reflex on manometry, they don't have Hirschsprung's and don't need biopsy

Manometry can have false absence of the reflex, so if reflex is absent you still have to biopsy

There are two definitions for ultra-short segment Hirschsprung's: absence of recto-anal inhibitory reflex with normal ganglion cells (internal sphincter achalasia), versus very short segment of true aganglionosis

Internal sphincter achalasia is not Hirschsprung's disease, it's a different entity

The anal canal in an adult is 3 to 4 centimeters long, versus 1 centimeter in an infant, so biopsies at 3 cm in an adolescent may actually be from the anal canal where there are normally no ganglion cells

In the anal canal there are no ganglion cells normally, but you should not see hypertrophic nerves

Biopsies from anal canal should show transitional epithelium, not normal rectum mucosa

Most cecal perforations from Hirschsprung's disease are not total colonic disease, they are shorter segment disease where the cecum gets distended and perforates like with a rectal cancer

In long segment disease, wait longer before pull-through (6 to 12 months) because patients have terrible perianal excoriation if pulled through too early, need to wait till stoma output thickens

Experience with very short pull-through using just the cecum has not been good, patients end up with stasis and enterocolitis from the big pouch reservoir

For ascending colon or cecal transition zones, treat like total colon disease and do ileal Duhamel rather than preserving the short colonic segment

If transition zone is at hepatic flexure, preserve the colon and bring it down, but if just cecum, sacrifice it

In older children trying to resect dilated colon transanally, the stretch put on the sphincter is enormous and continence postoperatively definitely suffers

For older children with dilated colon, go all the way down with laparoscopic dissection and do very little resection transanally to minimize sphincter stretch

In older children with massive dilation, distal bowel can shrink in size with a stoma for 6 or 8 months at age 3, making pull-through easier

The older the kid, the less likely the dilated bowel will shrink down in size with diversion

Biopsies done by colonoscopy in older children can miss Hirschsprung's disease, rectal biopsy is more reliable

The incidence of enterocolitis is significantly higher in children with trisomy 21, as much as double the incidence in genetically normal kids

Many kids need chronic metronidazole for enterocolitis, can be on it for three months, and when you try taking them off they start getting symptoms again, some need it for a long time

Botox injection decreased the number of hospitalizations for enterocolitis in children post-pull-through

Botox doesn't always work for enterocolitis, sometimes it works and sometimes it doesn't