All right time for the
third and final case.
This is a 46 year
with a past medical history
of Lyme disease.
Diagnosed and treated about
three years ago
who presents with
“I'm getting old doc”.
He reports that he has had six months
of increasing pain
and swelling and the fingers of both hands,
some neck pain,
back pain and general malaise. Now he
attributes his symptoms
to 25 years of carpentry work but he's
been taking time off
more and more due to discomfort when
he's holding his tools.
He's a nonsmoker. He does binge
drink on weekends
but he's been monogamous with
his wife for 20 years.
Family history is non-contributory.
So no help there.
In review systems he reports eczema
on his elbows and scalp
for the past several years,
no recent GI illness
or any genital urinary symptoms. Let's look
at a few key points here.
So the time course here is somewhat
chronic and progressive
whatever is going on is really
it's been going on for
the past six months.
Even if he has a baseline of some
osteoarthritic kind of stuff,
the pattern of joint involvement, it's a
little tricky to tell right now.
He's got some fingers involved
and maybe neck pain
but I still can't quite tell which
joints are involved.
If it's symmetric or asymmetric.
We're going to need
a physical exam to
highlight that one.
Same thing with joint
we're going to need a physical exam
and systemic involvement.
It doesn't sound like it based on
the review of systems
but I think we need some
So here's our physical exam. He's
a febrile, heart rate 72
blood pressure looks okay. He appears
older than his stated age
but he's a no Q distress,
He has a four by three centimeter
with scale on the right frontal
parietal scalp area.
In addition on his musculoskeletal exam,
we see warmth
and swelling in multiple fingers
on both hands.
Most notably at the DIPs more
so than in the PIPs
with diffuse swelling of his left index
finger shown here
which appears shorter than
the right index finger.
No wrist involvement. He has some
decreased neck range of motion.
Importantly, we did a Schober test again
looking for ankylosing spondylitis
which was negative. Skin and nails
reveal multiple nail pits
to most of his fingernails with some
evidence of Onycholysis
as well as the left second
and third digits.
He also has erythema dispatches with
scale noted to his bilateral elbows.
I guess that's what he was calling eczema
and also around his Umbilicus.
This picture shown here
on the right
by the way shows a classic
finding called Dactylitis
which is diffuse finger swelling or could
have also involved the toes.
We'll talk more about
that in a moment.
So just some representative photos of what
could be going on with our patient.
The first image here on the left shows
what could be scalp Psoriasis.
We're seeing some Erythema and
around where the hair
The middle image there shows
some Erythematous patches
with a little bit of silvery scale which
would be pretty consistent
with plaque psoriasis. Moving
over to the far right
we see a short arrow
showing nail pitting
and then the longer arrow is
or separation of the nail plate
from the nail bed.
Alright, so let's jump into
some laboratory data.
White counts okay, mild anemia,
ESR is borderline,
CRP is normal and his rheumatoid
factor is positive
but at very low levels, ATCCP is negative
which helps us
to steer away from
ANA is negative which takes
lupus off the table
and lyme serologies importantly are
just showing past infection.
Now as I mentioned before,
we can definitively say
the pattern of joint involvement
and polyarticular is a lot
of different joints
little joints involved. There is
we do think there's some
though it appears to
just be his skin.
Okay, so which of the following is
the most likely diagnosis?
Well, while the patient was calling
the lesions on his elbows eczema,
I think we can safely say that those
are psoriatic plaques.
80% of patients who develop
will have had a prior history
and he certainly seems to
fit the bill for that.
So we'll have to keep
this one on our list.
Next up is rheumatoid
Well in favor of that is involvement
of the hands and fingers.
He does have a loosely positive
But against it is that rheumatoid
arthritis usually involves
the wrist joints and the proximal interphalangeal
joints, not the DIPs
which is where the predominance
of his symptoms were found.
Likewise, the negative citric central native peptide
is going to really help us
to take rheumatoid arthritis
also off of our list.
Next up is lupus. Now
a nine to one ratio for favoring
lupus for women
and he of course is
a middle aged man,
he's not meeting the demographic
features at all.
Moreover, he doesn't really have evidence
of systemic involvement
other than the skin and
the skin findings
he does have are not
really typical of lupus.
The one exception perhaps is
the lesion on his scalp
could be discoid lupus, but I'm thinking
it's more likely scalp psoriasis.
Most importantly, a negative ANA
takes lupus off our list.
Next up Lyme disease. Now he
had negative Lyme serologies,
or at least those that only
showed past infection.
There is this concept of a post
Lyme disease syndrome
characterized by persistent fatigue,
but it very, very rarely would last
more than six months
and his infection was
three years ago.
You also wouldn't have all this evidence of
active inflammation going on.
So I think we can safely take
that one off the list too.
Now, reactive arthritis. Well, it's
supported by some features.
I mean, there's something
that certainly looks like
an axial Spondyloarthritis here, but we're not
getting anything in the history
about any antecedent
GI or GU symptoms.
The writers of a case for the boards are
going to include those things
before giving you a case
of reactive arthritis,
so we can safely take that
one off the list too.
Lastly, septic joint. You don't get
Polly articular septic joint
except under extreme circumstances.
So that one right off the bat, it's gone.
All right. Again, we've used the
process of elimination
to identify psoriatic arthritis as
our leading diagnosis.
So now let's revisit some
key points in this case.