There are some situations, however,
where behavioral modification
simply isn’t enough,
and this is one of them.
So this is Hirschsprung’s disease, which
is a congenital aganglionic megacolon.
The problem here is in the mucosa,
which you can see here in the slide,
the nerves have not successfully
entered the smooth muscle
and the muscle of the
As a result, they’re having a hard
time relaxing the rectal tone.
Because that rectal tone will not relax,
these children simply aren’t
capable of defecating,
whether they want to or not, and no
matter how much fiber is in their diet.
This is a congenital absence of
ganglion cells in the bowel wall.
So this happens because of a failure
of neural crest cell migration
from the proximal to the distal bowel.
It is sporadic.
It’s not necessarily inherited, it’s
just something that happens to happen.
And this absence of submucosal
and myenteric plexus
results in an inability to relax
the bowel and obstruction.
It begins at the anus and extends
proximally in a continuous manner.
That is to say that you will
notice there’s no skip lesions.
There are variable amounts
of bowel involvement.
About 80% of children only have the distal
end of the rectosigmoid colon involved.
However, 10% to 15% will have
involvement of the entire colon;
5% will have entire bowel involvement.
So very severe Hirschsprung’s
presents typically earlier,
and some children present later
because they are getting by okay
and the parents are just considering
their child a very constipated child
but it’s not until later that people
figure out that this was the problem.
In neonates, they’ll present generally
with a failure to pass meconium.
Remember that 48-hour rule.
We really want to see the
meconium come by then.
Another problem that might cause
that, remember, is cystic fibrosis.
These infants or neonates
will have distended abdomens,
they may have emesis, and they will
often have feeding intolerance
because they just feel full and
don’t want to eat anymore.
Older infants usually have a
history of chronic constipation.
This is a problem that’s been
going on for a long time,
and the parents are sometimes frustrated,
they can’t figure out what’s going on.
There’s often dilatation
of proximal bowel
retained fecal material.
These children may have failure to thrive
because they’re not eating
as much as they should
because of a feeling of satiety and
discomfort from their abdomen.
And remember, children with
can become septic with a
simple viral gastroenteritis.
While we think of this as a completely
benign entity in other children,
children with Hirschsprung’s disease,
the diarrhea has nowhere to go.
This causes an intestinal
dilatation which can cause bacteria
to migrate into the
and those children can
go into septic shock,
develop peritonitis and get in big trouble.
We really worry about even
in children with
So, if we suspect Hirschsprung’s
disease, what are we going to do?
Well, the gold standard is
a rectal suction biopsy.
The surgeon will go in and create
some suction on the rectal vault wall
and take a biopsy and then
we'll look for ganglion cells.
There won’t be any.
The problem is that in a
normal rectal biopsy,
occasionally, you just haven’t
happen to find the ganglion cells.
So this isn’t totally as
straightforward as you'd expect.
You’re always worried that you’re
falsely diagnosing someone
just because you haven’t
found the ganglion cells.
This becomes a pathologist on a search
for something that really isn’t there.
Sometimes, a contrast enema
can tell us some clues.
We may see a transition
zone on the enema
between the narrow
aganglionic distal bowel,
and then proximally, the distended
normal bowel before it.
And if we see a clear transition zone,
that may be a clue that this
is Hirschsprung’s disease.
Flipside, and this is unusual but it certainly
can be done when we’re still not sure.
We can dilate the anal sphincter and then
measure the pressure with that balloon.
If the anal sphincter is not
relaxing as the rectum is dilated, y
you have a sense that there’s a
problem with the anal rectal tone
because normally, the rectal
sphincter should relax
as it allows to pass fecal
material through it.
So, what is the treatment
of Hirschsprung’s disease?
Surgery is the only therapy, and
this is a little bit difficult.
Typically, we resect aganglionic
bowel however much there is,
and do a pull through of normal bowel
for an anastomosis with the anus.
Sometimes, surgeons can create a
little bit of a rectal pouch,
but these patients have a hard time
stooling for the rest of their life.
They can have normal
but sometimes they have
to stool more frequently.
There are potential
First is they may have fecal incontinence
from a smaller rectal pouch
that has been reconstructed
and fecal material
can leak through.
They may have residual constipation if there
is remaining aganglionic bowel there.
And again, the enterocolitis
problem can still
rear its ugly head for several
months after the surgery.
So, we still worry about
gastroenteritis in these children,
and if they are treated
they may be empirically placed on broad
spectrum antibiotics such as Zosyn
until they’re feeling better to prevent
bacterial invasion into the
bowel wall and peritonitis.
That’s everything I have for you today about
constipation and Hirschsprung’s disease.
Thanks for your attention.