00:01
So, this is a nice little picture here
to show you extravascular hemolysis.
00:04
Close your eyes, who’s your patient?
Is it significant hemoglobinuria
or is it significant jaundice?
Good.
00:11
Significant jaundice.
00:13
Let me set this up.
00:16
We’re at the spleen, so therefore
here’s my sinusoid of a normal RBC.
00:20
If it’s a normal RBC, what’s
the lifespan of an RBC?
120 days.
00:26
And so therefore, if you have an RBC
that has central pallor as you see here,
well it’s not going to be destroyed
by the spleen prematurely.
00:33
However, let us now go into the
cords of Billroth, where are you?
You’re in basically --
where the spleen and
you see the guests.
00:44
What guests?
You see these green cells
that we see on the lining,
these are the guests that you invited
to dinner and they are hungry.
00:53
And so now, what are you
going to serve them?
The appetizers.
00:56
What are these appetizers?
Oh, well, I’m going to serve you our
famous dish known as sickle cell.
01:04
And so now, what happens?
These RBCs are going to crazy
because they love sickle cell.
01:09
No, you didn’t have to make this.
01:10
The point is you have a
cell that becomes sickled.
01:15
It will be taken out
of your vasculature,
taken to the spleen.
01:18
So therefore, what kind of hemolysis?
Extravascular.
01:22
Can you tell me as to what your sickle
cell patient is going to look like?
Good.
01:25
Jaundiced, icteric.
01:28
Now, jaundice can quite difficult
to see in Africans, correct?
And so therefore, you’re really looking
for that icterus, is that clear?
Next,
well, oh my goodness, you really
didn’t have to make this.
01:40
You made a spherocyte?
It’s my favorite.
01:43
So now, you have a splenic macrophage
which is going crazy on a spherocyte.
01:48
Once again, tell me about
hereditary spherocyte.
01:51
Good.
01:51
Jaundice, icterus.
01:54
Are you seeing a pattern now?
So you’ll notice, please, with
your sickle and spherocyte,
that is not what a normal
RBC should look like.
02:02
And so therefore, these then will be
destroyed by the spleen very, very quickly.
02:06
And the last one over here
that you’ll see is an IgG,
and later on, we’ll talk about what’s known
as your autoimmune hemolytic anemia.
02:14
And what does an IgG mean?
Well, this is desert?
Really, you didn’t have to make this.
02:19
How did you know
that I like fondue?
What does that mean?
IgG and C3b, you’ve learned in
immunology that these are opsonins.
02:26
What’s an opsonin?
It’s taking these “fruits,”
maybe a strawberry, you
dip it into chocolate.
02:35
That chocolate will be the opsonin.
02:36
What are the opsonins?
IgG and C3b.
02:39
Well, some people might
not like strawberries,
but oh boy, you dip it into
chocolate, it’s their favorite.
02:45
So now, you’ve made
the RBC really tasty.
02:51
For whom?
The splenic macrophage.
02:52
Guess what kind of hemolysis?
Good.
02:56
Extravascular.
02:56
Are you seeing the pattern here?
Understand where we are
and what the disease is.
03:02
Ultimately, understand
who your patient is.
03:04
All jokes aside, this
is a serious matter.
03:06
So the bottom portion here
is that you’re going to be
releasing unconjugated bilirubin.
03:13
What is the laboratory term
that we use in medicine?
U-N is I-N.
03:17
Indirect.
03:18
Which means what?
Lipid soluble.
03:22
And you would expect to
find lactate dehydrogenase,
but that is going to be nonspecific.
03:25
You’ll find that both in
intra and extravascular.
03:29
Make sure you spend a little bit of time and
you understand this in its completeness.
03:31
Now, let’s move on.