Let’s move on to another cause of
which is biliary atresia.
This is a complete or partial obstruction
of the lumen of the extrahepatic biliary
tree within the first three months of life.
So this is not an intrahepatic problem.
This is an extrahepatic problem.
And what we typically see as you can
see on the left side of your slide
is inflammation along the biliary tree with
this sort of chain of lakes phenomenon
where there are multiple
constrictions of the biliary tract.
So let’s go through how this proceeds.
Normal development of biliary tree
and then patient may have an
insult generally perinatally
such as a viral infection or some problem
that causes the bile ducts to be inflamed,
some sort of injury
to the mucosa.
This results in inflammatory response and
immunologic response inside the duct
and leads to infiltration of
the duct and obstruction.
This duct reaction causes an epithelial
proliferation of the cells within the duct
which results in a progressive
sclerosis and fibrosis of the duct,
which thus is going to
obliterate these ducts.
This usually happens within
the first month of life
and leads to a cholestasis,
essentially an inability to get bile
through those ducts leading to a backup,
which results in hepatocellular
injury and a secondary cirrhosis.
So if you suspect biliary
atresia, what should you do?
Well, of course, it’s important
to take a good history.
And typically, these
are healthy newborns,
they’re full term, they
have normal weight gain.
They don’t have a history of a
maternal infection in utero
because this is an acute thing
that happened after birth.
They’ll have a brief perinatal jaundice
and then be jaundice free because that
was an unconjugated hyperbilirubinemia.
And then they develop
the jaundice later.
Generally, it’s a progressive jaundice
that happens about eight weeks out.
And these children will often
have acholic or pale stools.
You’ll see this because the child
is not able to extrude the bile,
which is the main source
of pigment in stool.
These stools like almost
chalky and white in nature.
The child will also have dark urine
because there will be urobilinogen
spilling into their urine.
On exam, you will of course see the
jaundice, you should see scleral icterus.
But generally, these children
are very well-appearing.
children who look okay.
They’re just turning yellow.
You may notice a soft hepatomegaly,
not a firm mass-like thing,
but generally a large liver
and they may have a mild spleen as
well simply from vascular backup.
And generally, you get labs
and you’ll notice typically
their total bilirubin
levels around 7 to 10,
with a direct level
of around 3 to 6.
And as you can see, this clearly meets
criteria for conjugated hyperbilirubinemia.
They should have a bumped GGT because of
that inflammation to the biliary tract
and an alk phos, and of
course a bumped AST and ALT
as well as they’re now developing
hepatotoxicity from the bile backup.
So we diagnose this condition
through ultrasound primarily.
And if there’s more
delineation that’s required,
we can do a HIDA scan as is pictured
above in the first picture.
Or we can do an
which may be useful at determining what
type of problem is truly going on.
The patient is repaired through surgery
and a Kasai procedure or a Kasai
portoenterostomy is performed
where the liver is
essentially filleted open
and directly anastomosed
to a piece of intestine,
allowing those multiple ducts to spill
directly into the intestinal vault.
Usually through a roux-en-Y or some
sort of similar surgical procedure.
Transplant may have to occur and that
is typically curative of the problem.