Now moving forward, apart
from acute blood loss
and still in the realm of
normocytic non-hemolytic anemia,
let us now move in
to the bone marrow.
And for whatever reason,
we’re going to shut it down.
If you shut down your bone
marrow, then what happens?
Well you can’t produce
reticulocytes, can you?
what’s the concept?
It’s the fact that you have a decreased
reticulocyte production index
or as it says here
And that magic corrected
reticulocyte number is less than 3%.
That you’ll have to memorize
but the concept is clear.
It’s a fact that the bone
marrow has been shut down.
Well, we’ll get into
this in a second.
Bone marrow cellularity rule-of-thumb.
So if the bone marrow has been shut down,
think about what the bone
marrow should look like.
It should be nice and empty.
There should be lipid.
There should be fat vacuoles and obviously,
there should be hematopoietic stem cells.
And there should be those
primitive type of blasts, right?
Now, not too much and not
too little, just right.
And so that you can then produce a
proper homeostatic churning or synthesis
of the stem cells
that we require.
However, if the bone marrow
for whatever reason,
let’s say that this patient
has aplastic anemia,
then understand that at this point,
the bone marrow is completely dead
and is pretty empty.
I’ll show you pictures.
Now, as a rule-of-thumb which
you can use as 100 minus age
gives you approximate normal
cellularity of your bone marrow.
Just the generality, but as far
as your concern, it would work.
Now the causes, what’s
causing aplastic anemia?
What is then causing the bone marrow
to become aplastic or hypocellular?
Well, pancytopenia is just a term
that we use for what, please?
Usually it’s in reference
to the trilineage.
And by trilineage we are referring to,
obviously, the RBCs,
And of all the granulocytes,
which one do we normally have in our
body circulating predominantly?
So that’s usually what you were
referring to when you say pancytopenia
and each one of those loss of the lineages
is going to give you different
symptoms in your patient.
For example, if there is no RBC, your
patient is going to present how?
Fatigued and tired.
If your patient has not enough
platelets, what is that presenting with?
Obviously excess bleeding
that can form a clot.
And if they don’t have neutrophils,
what does that mean to you?
Oh, they are now
susceptible to infection.
Those are three that you want to take
a look at when you have pancytopenia.
Earlier, we have talked about this in
terms of megaloblastic anemia, right?
In megaloblastic anemia, remember please,
you were still producing your
cells but they were blasts.
But just because you’ve formed a cell,
if it hasn’t matured then it can’t
carry out its function, can it?
Of course not.
So those megaloblastic anemia
or the megaloblastic cells
and hypersegmented neutrophils
with B12 and folate,
yes, there is pancytopenia but
that is not aplastic anemia.
Is that clear?
By definition, if it’s aplastic anemia,
it means that you had
no cells being produced
because the bone marrow
had been shut down
and so therefore in the category of
normocytic non-hemolytic anemia.
Keep that in mind as
you move forward.
Now bone marrow failure,
idiopathic/autoimmune being the most common.
You find that occurring
with many organ damage.
Drugs including chloramphenicol
Chemosuppression, right, in general
or bone marrow suppression.
Usually looking at those
cells that like to divide.
Tell me about your stem cells.
What kind of cells are they?
They are labile, aren't they?
They love to proliferate,
And so therefore with chemotherapy, looking
at those cells that love to proliferate
and unfortunately instead of attacking the
cancer, may also have collateral damage.
You’ve heard of bone
You’ve heard of hair loss.
And there is massive diarrhea, isn't there?
In those patients that are taking
Quite a bit of pain.
Sometimes the chemo is worse
than the disease itself.
Infection, we have parvovirus B19.
Now, what we’ll do here, is well, is
anytime parvovirus --
is it possible that you might have a
patient that has another type of anemia
such as hemolytic anemia and then may then
have a parvovirus B19 virus infection?
And so therefore, at that
point, where do you move in to?
What’s my topic here or category?
Normocytic non-hemolytic because the
bone marrow has been shut down.
Now, with Diamond-Blackfan syndrome,
we’ll talk about this a little bit more.
But what I do wish for you to
keep in mind is the following.
Diamond-Blackfan syndrome can come
under either your bone marrow failure
where this is normocytic
and please be careful
could also be part of your
We’ll talk more about that later.
But that is one that you
want to pay attention to.
Fanconi’s anemia, there, what
you want to pay attention to
is do not confuse that
with Fanconi’s syndrome
which is a problem with the proximal
convoluted tubule in the kidney.
One has nothing to do with the other.
These are all the different causes that
you want to be quite familiar with
with bone marrow failure.
So what is Diamond Blackfan syndrome?