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,
the 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
able 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 say, 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.
Next, these neutrophils
are coming in.
And what’d they do?
Taking a bite out
of these bacteria.
And bacteria made up of what?
Say that I’m going to breakdown my cells,
then I’m going to breakdown myself.
Say that I am the bacteria and there is
a neutrophil coming in to attack me.
What are you going to be left with?
My residue, as a human being or bacteria
is going to be protein, protein, protein.
Hence, your protein
levels will be higher
and the cerebrospinal fluid
with bacterial meningitis.
Don’t memorize that part.
You understand the concept.
Then if you want, memorize
some of these values.
Are we okay so far?
Let’s go on to fungal and viral
meningitis and group these together.
So under fungal, let’s say that
this patient is HIV positive.
Maybe unfortunately goes on to
contract Cryptococcal leptomeningitis.
Viral meningitis, I’ll walk
you through a few of these.
A little bit different before
we move on once again.
If you have an infection, you can
expect that WBC count to be elevated,
but definitely not as high as
what you find with bacteria.
Next, if 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.
Or maybe lymphocytes, in fact.
RBC count relatively
normal and then glucose.
Remember, these are viruses
and fungal and so therefore,
the glucose consumption
is not going to be as
dramatic as what we saw
with bacterial, correct?
your glucose level here could
be within normal range.
Protein here, viruses,
you’ve heard of single-stranded
and double-stranded DNA and such.
Single-stranded, a little
scrawny sucker, right?
And if you’re going to break me
down as being a little skinny dude,
then what’s going to happen?
I’m not going to release
much protein, am I?
So therefore, take a look at the
differences, contrast please.
The protein content and CSF and bacterial,
which is higher and viral granted, yes.
It’s a little bit higher but definitely not
as high as what you'd 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 is every possibility that both
of these 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 a neutrophil predominantly,
granted a little bit,
but not predominantly.
Here, the RBCs would be elevated with
the HSV because I were talking about
involvement of the brain
parenchyma as well.
So this becomes important
for us, doesn’t it?
So I need you 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, your glucose
could be greater than 30.
And then here, the protein, once again,
higher but definitely not as high
as what you'd find with bacterial.
So be careful when
your doing herpes
and we 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 the pathogenesis
of each one of these categories.
Do not worry.
Let's talk about brain abscesses.
Brain abscesses, you should be thinking
about bacterial, more or less.
WBCs will be elevated.
Brain abscess here though, we’re talking
about neutrophils not being as high.
RBCs would be elevated more so,
because we’re talking about
once again the brain
And so therefore, the CSF is reflecting
the damage to the brain, say in concept.
Here, the glucose could be elevated
and the protein would be higher.
We’ll talk a little bit more about brain
abscess in the form of ring-form of lesion.
You will know for sure that you are
dealing with the brain abscess.
But overall, here’s a
really good extensive table
for you to evaluate some of
your cerebrospinal fluid.