welcome to another MedCram lecture the first in the series that we're going to
talk about as we go through the CBC is the WBC and we'll talk about increased
WBC here under the term leukocytosis okay so a couple of points regarding
leukocytosis you know we're looking at a patient most typically in the hospital
but this could also be seen as an outpatient as well you should know that
the normal range is about 4.5 to 11 and then you'll have this term times 10 to
the 9th which is like a billion divided into one liter so how many cells you see
in in one liter so obviously anything greater than 11 is going to define
leukocytosis okay but it can go as high as a hundred thousand you want to watch
trends as we talked about in the first video so you know a 13 on a white blood
cell count may be elevated but if the previous one was 20 and it's coming down
to 13 then that's a process that's actually resolving and 13 is not to be
worried about if on the other hand you've got a 5 and it's going to 13
that's something that obviously we need to worry about more okay so again as
always watch the trends and then differential so the white count as you
may know our white blood cells that's what the leuco means that's white so
these white blood cells are part of your immune system but these white blood
cells are actually a collection of other cells there are bands there are
segmented neutrophils we call those CEG's
and these all sort of make up your neutrophils but then you also have
lymphocytes you have monocytes you also have eosinophils okay so they all have
their own function typically the bands and the neutrophils are seen elevated in
pyogenic infections lymphocytes can also be elevated but they're usually more
typical for viral okay so be aware of that you also may see this in
tuberculosis same with monocytes you might see monocytes elevated in
tuberculosis and also certain viral infections the one that you should know
about though is eosinophils anytime you see elevated eosinophil
you need to think about two things specifically one is either an allergy
also think about parasites so think about drug allergies if you see
high eosinophils think about parasites and there's also a third thing that you
should think about is well I'll put it up here and this is just to keep in the
back of your mind is Coxie coccidia mycosis which is a fungus that typically
lives in the Southwest United States also in parts of South America Central
America and that's a famous one that they like to use I bring it up because
that's where I live in this part of the world where we see coccidia mycosis and
yoson Affiliate is a nonspecific thing that you might see but think about coxy
think about allergies think about parasites if you see elevated eosinophil
there's other things that can do it but that's one of the things that can do it
but the one that you're probably going to see the most are these bands CEG's
neutrophils and that will be elevated in pyogenic or bacterial infections and
there's usually a range so typically what you would see in terms of percent
is maybe about 60 percent will be bands and CEG's maybe about 22 or so percent
and this won't add up to 100% but around 20 percent or so for lymphocytes about
5% for monocytes maybe 2 to 4% for yo sinha fills okay if you see a deviation
from that then you know that there is a simple line that is increased so if this
lymphocytes all of a sudden shoot up think about viruses if this segments go
from 60 to 80 or 90 think about a pyogenic or bacterial infection if
instead of 4% you're at 20% start thinking about what we talked about coxy
allergy or parasites so we talked about what's normal we talked about watching
the trend we talked about the differential let's talk about causes and
what to do if the white count starts going up on you on a patient in the
hospital so in terms of causes the big four that I want you to know our
infection steroids cancer / leukemia or a catastrophic
event and these are kind of listed in order of the most common let's talk
about infection first so typically with infection you're gonna see
something called a left shift and what that means simply is that bands are
basically released from the bone marrow and then it becomes segmented in
neutrophils okay otherwise known as PM ends what happens is you see of very
little bands and a lot of CEG's normally and when you have an infection the bands
start to be released more and more and so you see the bands start to go up in
circulation they'll actually tell you how many bands there are if you start to
see bands in circulation that's a very good indication that what you're dealing
with with an elevated white count is an infection the things that you want to
look for clinically look for fever that will also tell you that that's what it
is that's going on look for signs of infection okay
the other thing to do is ask the patient do they have pain that's usually a sign
that there's an infection somewhere so look for corroborating evidence that
there is an infection going on if you can't find it start to do diagnostic
tests to confirm it so things that might be able to do it
chest x-ray get a urinalysis you might even need to get a CT scan to
look if the patient has a fever and is altered by all means get a lumbar
puncture to rule out meningitis the biggest infections are pneumonia which
you'll see on a chest x-ray a urinary tract infection which you'll see on a
urinalysis look at their skin see if they've got cellulitis somewhere examine
their belly see if they're tender think about cholecystitis think about
diverticulitis all of these things are going to cause an elevation in the white
blood cell count okay the other thing that you'll see is steroids so a lot of
time people will come in and they'll need steroids for either a COPD
exacerbation or they'll need steroids for an asthma exacerbation and you'll
put patients on stage for whatever reason what you'll notice almost
invariably is the WBC count is going to go up now
why does the WBC count go up it goes up for three reasons and this will help us
decide and distinguish between why it might be an infection okay the first
reason is is something called D margination what does this mean here's
your vessel with the white blood cells the middle of it what you don't realize
is that their white blood cells are already adhered to the wall and so what
happens is the steroids cause these cells to come into the center of the
blood vessel so when you draw the blood you're gonna get more of those white
blood cells in your sample that's de margination about 60% of the effect that
we see with an elevated white count is from D margination now the other thing
that might cause this is delayed migration so everybody knows that these
white cells go out of the blood vessel and into the tissue that's where they
fight infections in the tissue well if you delay that migration of cells of
white blood cells into the tissue they're going to be more likely to be in
the blood vessel when you draw the blood and get the leukocytosis and we see that
about 30% of that effect is due to that the last one that we see here is about
10% of the effect and that is bands released from the bone marrow but this
is such a small proportion of the reason why the white blood cells go up so small
that in fact we can actually look at this situation and say that if you see
the bands going up significantly it's probably not from steroids it's probably
an infection and that if we see all of the different white blood cells going
out for instance we see the lymphocytes and the neutrophils and the monocytes
and they're all going up proportionately that's usually a result of D margination
and that's typically what we're gonna see in steroid use so if you've got a
patient has pneumonia and you put them on steroids because they're having a
COPD exacerbation because of the pneumonia and the white cells go up but
you don't see a left shift you don't see band emia then you can probably chalk
that up to steroids within reason right steroids are only
gonna make the white blood cell go up you know maybe from 12 to 20 at most
okay if you start to see 30 40 50 then there's gonna be a problem speaking of
which if we go back to infection on number one there is a very famous
infection that I would be remiss in mentioning that we see in patients
especially in the hospital and that corollary is c-diff okay I don't want
you to miss that if you start to see white counts in the 30 to 40 to 50 and
higher range okay so these incredibly high white blood cells something you
have to think about is Clostridium difficile colitis and in this situation
you typically do imaging like a CT scan to look at the bowel wall and you'll see
thickening of the colonic wall in that situation typically the treatment
includes pio vancomycin not IV vancomycin but pio vancomycin and either
Pio or IV flagyl there are other treatments there's even surgical
treatments so the earlier you catch this the better
so think about seed if if you have a very very high white count okay so we
talked about certain types of infection we talked about steroids causing
elevated white-blood-cell the other thing that can do this is if there is a
leukemia of course remember with leukemia and lymphomas there's a problem
with the production or their survival of these white blood cells so in other
words there is some sort of gene that gets turned on and these white blood
cells start dividing rapidly and so you're making a lot of these and other
potential reason why you could have leukemia or lymphoma is if the cell
doesn't die and doesn't involute and just hangs around so there's different
variations on this of course you know that there is acute lymphocytic leukemia
there is chronic lymphocytic leukemia there is acute myelogenous leukemia
which is a really bad player and then there's chronic myelogenous leukemia
that's the one with the Philadelphia chromosome etc so all of these can do it
the thing that you must remember or one of the things that you should remember
is something called lap or leukocyte alkaline phosphatase and this is the
stuff inside the cells that is responsible for breaking down and
killing bacteria well in cancer cells each cell has a lower amount of this
leukocyte alkaline phosphatase so in the old days before we had flow cytometry
and more genetic ways of figuring out whether or not there was a leukemia or
lymphoma what they would do is check score okay and if there was a high
leukocytosis but a low lap score that was indicative of cancer leukemia if the
lab score was elevated that means that there was an appropriate amount of
leukocyte alkaline phosphatase in these cells and that probably wasn't it so
what should we look for again if it's a lymphocytic leukemia obviously we're
gonna see elevated amounts of lymphocytes and so if you see a high
white count and they're almost all lymphocytes think about this as a
diagnosis if on the other hand you see various different types of myelogenous
type of cells myelogenous meaning segmented neutrophils or eosinophils or
monocytes things of that nature then that would be something along the lines
of AML or even CML depending so these are divided okay what you really need is
a peripheral smear and you need a pathologist to review the cells to see
if they look atypical if they look atypical then you need to get even
deeper and you might even need a bone marrow biopsy done to evaluate for that
okay and then the last thing that we're going to talk about is catastrophic
event so a catastrophic event like a myocardial infarction or a cardiac
arrest or a massive pulmonary embolism is such a stress on the system or even
surgery could be a stress on the system that this would cause a transient
increase in the white count so what you would see is a bump up very quickly and
then the white count would come back down again as you were to track it okay
there are many other things that can cause leukocytosis that I have not
included here even a cold shower can make your white count go up so think
about these things as you look at your WBC on your CBC thanks for joining us