Moving on to duodenal atresia.
So here’s a classic case, a newborn with
Down’s syndrome and abdominal distention.
This four-day old infant with known
Down’s syndrome presents with
suspicious of obstruction.
A child is vomiting just
about everything he gets.
Clearly, Down’s syndrome
and abdominal distention
is a risk factor for
So intestinal atresias,
all of them,
are basically a failure of the hollow
viscous organ to develop properly.
Instead of being hollow, it’s constricted
and obstructs passage of food.
There’s a spectrum of severity,
some are very badly atretic and
some are only minimally atretic.
But what we do know is duodenal
atresia is very closely
associated with trisomy
21 or Down’s syndrome.
That is a very high-yield
point on an exam.
Remember that connection.
So typically, the stenosis
of any type of intestine,
which is more common in the duodenum,
occurs between two segments of bowel
with or without a separating web.
The atresia will be a connecting fibrous
band between those two segments of bowel
and it can result in two blind pouches
of bile, that’s the most common kind.
So what do we do in terms
of diagnostic testing?
Typically, we can get
They will show obstruction, maybe
pneumoperitoneum if it’s gone very far,
and perhaps meconium peritonitis
if it’s been left going too long.
The classic finding that is likely to be
on your test is the double bubble sign.
What you will see is two round air-filled
locations on an intestinal X-ray.
This is a picture of colonic atresia,
not the double bubble sign,
but the idea is still there.
You have an area where fluid is getting
and then where fluid is not getting.
Sometimes, we’ll do contrast
studies such as in this image,
where an upper GI series may reveal a
malrotation in addition to the double bubble.
In this case, where a
patient has a microcolon,
you can see an area where
the colon is atretic.
Remember, and this is also
high-yield for your exam,
microcolon is associated with
maternal gestational diabetes.
So duodenal atresia, Down’s syndrome,
microcolon, maternal gestational diabetes.
Here is the double bubble sign.
And you can see the stomach filled with air
and the duodenum filled with air as well.
The reason why there’s a line there
is these are largely fluid contents
because the child is presumably
eating breast milk or formula,
so it layers out in a
Notice there is no gas distally.
This child is incapable of
creating gas distally because
nothing is getting into the
distal intestinal compartment.
It is impossible to miss this
for more than a few days
because the child will pass away
unless this is surgically corrected.
Food is not going through.
The surgical resection is essentially that.
They take out the atretic bowel
and they put the healthy pieces of
bowel back together as an anastomosis.
This allows the baby to recover
and have full function.