Let’s begin with acute meningitis.
So what is happening here?
Inflammation of the meninges,
leptomeningeal, and as I told you earlier,
where you will be paying attention
to and serious of detail,
is going to be the evaluation
of the cerebrospinal fluid.
That will then tell you or clue you in
what’s the cause of my acute meningitis.
Bacterial, fungal, viral, whatnot
or could be a combination where
you have meningoencephalitis.
What does that mean?
Well, what's adjacent
to the meninges again?
Of course, the brain parenchyma.
So don’t memorize,
just take a look.
If the meninges are undergoing
then as is at some point in time the
adjacent parenchyma of the brain
which then brings
into what definition?
Both the parenchyma and the meninges
undergoing pathologic changes.
Acute meningitis, infectious,
could be bacterial, viral.
You want to keep mycobacterial
Then you have spirochetal,
fungal and parasitic.
Granted mycobacterial and
spirochetal are, in fact,
bacterial, but I need
you to keep this separate.
Because as we go through meningitis,
I need you to be able to diagnose,
is my patient suffering from meningitis
as tuberculosis being the cause
or was it something like Lyme disease
referring to Borrelia burgdorferi.
overall theme, what’s
What’s my topic?
Acute meningitis, inflammatory
process, granted infections.
And I told you earlier, let's say
that there is chemical injury,
then what do you think that a
particular organ is going to do
undergoing inflammatory process,
but is it purely infectious?
Not really, right?
So we’ll talk about this quickly, a couple
of points on chemical and also neoplastic.
Neoplastic, of course,
is not being infectious,
but if you have neoplastic, let’s say,
changes taking place in the meninges.
Once again, you get the point.
Inflammation, acute meningitis.
Now, here’s a couple of tables here.
I’m not going to bore
you with the detail
and you know how to
read your tables.
These tables, as you
know, are money.
And so, by that I mean, if
you know these tables well,
do everything you're powered to.
Somehow, extract these tables out
of all of my lecture series.
Because, this then summarizes
and you will understand
what’s going on
with your patient.
But in order for these tables
to really make sense to you,
you need to make sure that you have a
full understand of the pathogenesis.
First, under the column
of no infection, WBC 0-6.
Now, when you say WBC,
what are you referring to?
Well, could it be a neutrophil?
Could it be a lymphocyte?
Keep that in mind.
So normally, let’s say 0-6.
What are we looking at?
We’re looking at the
What are we looking at?
Not the plasma, not the urine, you’re
looking at the cerebrospinal fluid.
There should normally be no neutrophil.
This is the first column.
RBCs very minimal.
Glucose, know 40-80, memorize that.
The reason I say that is because let’s talk
about bacterial meningitis for one second.
How do you think bacteria survive?
They survive by consuming
glucose, just as we do,
granted the metabolism a little
bit different biochemistry.
But nonetheless, bacteria is
going to consume glucose.
So therefore, what’d you expect the glucose
level to be in a bacterial meningitis?
What about viral?
Viruses are different
beasts, aren’t they?
They are magnanimous organisms
that know exactly
what they’re doing
and they’re very manipulative
and they use the host.
So that it can survive and duplicate,
as you know, from microbiology.
So the glucose levels, RBC will be
different from viral meningitis.
Memorize 40-80, please.
Protein, once again here, 20-50.
So as we go through this, let me give
you a little bit of understanding as to
why we find certain findings
in our cerebrospinal fluid.
If it’s acute bacterial meningitis,
I have an 18-year-old who
has gone to college,
staying in dorms and then you know about
your signs and symptoms of meningitis
that you’ve talked
about in microbiology
is going to be difficulty
with looking at lights.
Trust me, here I am in a
studio and these lights,
if I had meningitis, there is no way that
I could be in this room talking to you.
Because I’d be whimpering, right?
So photophobia, headaches, nuchal
rigidity if you heard it before,
Brudzinski sign, so
on and so forth.
Difficulty raising the legs.
So that’s your meningitis.
An 18-year-old gone to college,
at this point, you should know
about your bacteria or the species
causing the particular
Maybe it’s a Neisseria species, right?
If it’s a teenage college year.
What if it was a young
baby, a neonate?
The bacteria there is a little
bit different, isn’t it?
You’ve heard of your CAMP-positive
or maybe perhaps E. coli
So what I’m saying to you, at this
point, it would be a really good idea
for you to go back to
microbiology and pay attention to
what are the most common
that are causing meningitis,
based on the age groups.
Do that for me now,
then come back and then, you
memorize some of these numbers
or more importantly
understand the concepts.
Let us see, how about acute bacterial,
what does that mean to you?
What do you mean, what
does that mean to you?
In immunology, what are
you going to bring in?
What kind of cells?
So this neutrophil
specifically is then going
to contribute to that
increased WBC count.
That shouldn't be even a surprise.
Next, well, in terms of RBCs granted,
It might be a little bit more elevated,
but could be within normal range.
Now, here is that all-important fact
that I just walked you through.
In order for these prokaryotes to
function properly and to thrive,
they require energy
in a form of what?
They’re consuming glucose.
Take a look, please.
Cerebrospinal fluid with bacterial
infection, meningitis less than 30.
Point is, the concept of
consumption of glucose.
Hence, your protein levels
will be higher.
The main cause of
protein level elevation
is the severe disruption
of the CSF blood barrier,
which is also responsible for the
markedly elevated WBC counts
seen in bacterial meningitis.
In the cerebral spinal fluid
with bacterial meningitis.
Don't memorize that part.
You understand the concept.
Then if you want to
memorize some of these values.
Are we okay so far?
Let's go on to
fungal and viral meningitis
group these together.
So under fungal, let's say that this
patient is HIV positive, maybe.
Unfortunately, goes on to
type of meningitis.
I'll walk you through
a few of these.
A little bit different
before we move on.
Once again, if an infection you can
expect the WBC count to be elevated,
but definitely not as high
as what you find with bacterial.
If the viral,
what kind of WBC would you expect?
Not so much neutrophil, huh,
not so much neutrophil.
Granted, maybe a little bit,
but not so much.
More maybe lymphocytes, in fact.
RBC count relatively normal,
and then glucose.
are viruses and fungal.
And so, therefore,
the glucose consumption
is not going to be as dramatic as
what we saw with bacterial, correct?
Look, your glucose level here could
be within normal range.
Protein here is mildly elevated,
because the disruption
of the CSF blood barrier
in viral meningitis is minimal.
So therefore, take a look at
the difference is contrast please
the protein content, and CSF,
which is higher and viral,
It's a little bit higher,
but definitely not as high as
what you find with bacterial.
Let's move on.
Let's say that your patient is
suffering from HSV encephalitis.
Remember, you can have a combination
of meningoencephalitis, can't you?
So be careful there.
Use it as a continuum.
You know that the meninges
are adjacent to the parenchyma.
There's every possibility that both
of the structures could be affected.
Here, the WBC count,
we're talking about a virus.
So therefore it will be elevated.
But here, the WBC type would
not be neutrophil predominantly
Granted? A little bit,
but not predominantly.
Here, the RBCs would be elevated
with the HSV,
because now we're talking about
involvement of the
brain parenchyma as well.
So this becomes important for us,
10 to 500.
So I need to stop here, digest this,
under HSV encephalitis, please.
Let's move on.
What about glucose?
Remember, once again,
this is a virus.
Therefore, you're not going to
consume as much
and so therefore,
glucose could be greater than 30.
And then hear the protein,
higher but definitely not as high
as what you find with bacterial.
So be careful when you're
And when you do encephalitis,
it's also the meninges
that could be affected.
And if you're evaluating your CSF,
RBCs will play a role.
We'll talk more about
of each one
of these categories.
Do not worry.
Let's talk about
you should be thinking
about bacterial more or less.
WBC's will be elevated.
Brain abscess here though,
we're talking about neutrophils
not being as high.
RBCs would be elevated more so
because you're talking about,
once again the brain being affected.
And so, therefore, the CSF is
reflecting the damage to the brain.
Here, the glucose could be elevated
and the protein would be higher.
We'll talk a little bit more about
in the form of
ring forming lesion.
You will know for sure
that you're dealing with
the brain abscess.
But overall, here's a really
good extensive table
for you to evaluate some of your
cerebral spinal fluid.