Okay, today we're gonna talk
about gout and pseudogout.
Fist off, let's do a case.
A 51-year old man presents to your office with
5 days of right knee and left ankle pain.
His past medical history is notable for HIV with undetectable
viral load, hypertension, CKD stage III, obesity and gout.
He was also recently hospitalized for
a MRSA cellulitis about 2 weeks ago.
He denies any recent hiking or gardening and his
medications include chlorthalidone, gabapentin
and he is also on on some
antiretroviral medication for his HIV.
Initial vitals, a little bit of a temperature
37.8 C, heart rate's 87, blood pressure is okay.
On exam, he has a hot, swollen right
knee and a warm, left, swollen ankle.
Skin exam is normal.
His creatinine is 1.6 with a baseline of
1.5, indicative of his stage III kidney disease
and his white count's a little
elevated at 10.4
Uric acid 7.8
So let's use those 4 important features to try and characterize
or draw out some of the important features of the case.
So, time course, sounds
like it's subacute.
It's been going on
for about 5 days.
Next up, the pattern of joint involvement,
well, it's his right knee and his left ankle.
So, it's asymmetric and since it involves 2 to 4
joints, we would use the term oligoarticular.
Thirdly, looks like with a hot, swollen
knee, the very definition of inflammation,
we do have evidence of joint inflammation.
And lastly, is there
Temperature of 37.8 maybe suggest
low-grade fever but hard to say at this time.
We'll have to get some blood work.
Blood work there, at least initially, again, a
mild white count but not much else going on.
So, let's look at our
So the things at this point, in favor of gout is
the fact that, hey! he's got a history of gout.
Uric acid level of 7.8 is important.
Keep in mind that a uric acid
level should be less than 7
and the supersaturation
point for uric acid is around 7.
But many patients can have an elevated uric
acid level without any evidence of gout.
So that's something to keep in mind.
His recent hospitalization as
we'll see later is also relevant.
In favor of pseudogout,
it involves the knee.
He does have a history of
hypertension, we'll talk about that later.
And the things that are
in favor of septic joint,
he's immunocompromised with his HIV
status even if his CD-4 count is okay.
He did just have a MRSA cellulitis
so we're worried about bacteremia
and seeding a joint and thus
have a low grade temperature.
And lastly, in favor of Lyme is the fact that he had an
oligoarticular arthritis with a low grade temperature,
that's pretty classic
presentation for Lyme.
So at the moment, we kinda have all 4 of
these items is on our differential diagosis.