Here, we have brain abscess.
With the brain abscess, acute focal
suppurative infection of brain parenchyma.
What does suppurative mean to you?
Under brain abscess, there
might be direct seeding.
Or it could be hematogenous.
Acute bacterial endocarditis.
Or cyanotic congenital heart defects.
So anyone of these
type of presentations
could then result in
eventual brain abscess.
Clinical features: Headache,
nausea with vomiting,
papilledema, focal neurologic,
Elevated CSF, WBC count,
and here we go,
lesion on CT or MRI.
So now let’s step back for one second
and at least, at least, review
the three different ring enhancing
lesion that we’ve seen.
AIDS patient, immunocompromised.
Most common CNS infection in an
AIDS patient, toxoplasmosis.
What if serology comes back to be negative?
You still move forward with treatment
because your patient has AIDS.
How long do you give therapy?
Then we looked another
ring enhancing lesion
during active, active, infection
It could be ring enhancing.
But I told you most common presentation
would be a calcified cyst in the brain
and then we have brain abscess.
And here, we have ring enhancing lesion.
Pathogenesis, well, we’ll just walk through
how maybe a patient has endocarditis.
Maybe there is a direct seeding, so
on and so forth, hematogenous spread.
Edema, ring enhancing lesion,
and an abscess core.
So in other words, this time,
we don’t have calcifications.
So therefore, we have a
ring with an abscess core.
What does an abscess
core mean to you?
And what does that abscess core mean to
you apart from neutrophils coming in?
What kind of necrosis is this?
It will be liquefactive necrosis.
Because neutrophils are destroying
everything in its path.