Alright. Today, we're going to cover a big topic, Vasculitis. Let's go through a case.
A 37-year-old woman with a history of asthma presents with dyspnea, abdominal pain. She
was diagnosed with asthma at age 19 and has had exacerbations with increasing frequency
over the past several years despite the use of a maximum dose of a fluticasone inhaler. Over
the past few weeks, she has also had increasing episodes of abdominal pain after eating large
meals and yesterday morning she noted that her left foot seems to be dragging a bit. She also
reports fevers, a 15-pound weight loss but she denies any coughing or sore throat or diarrhea.
On review of systems, we also find that she is supporting a rash on both of her elbows. No eye
pain, no redness, no joint pain. She's a non-smoker, she drinks socially, occasionally uses crack
cocaine. Family history is non-contributory. So that's a lot of information. Let's try and at least
highlight 4 particular variables that we always do. Number 1, the time course. This is a complicated
time course. On 1 hand, we've got something that's been going on since she was 19 for 20
years, that's increasing asthma exacerbations that have been gradually increasing over time.
But then we've got some new symptoms starting a few weeks ago and then we've got things
that just started yesterday morning so I'd call this an acute on sub-acute on chronic kind of
picture. Next up, the pattern of disease. We've got a lot of systems involved here. We've got
the lungs, some abdominal pain suggested gastrointestinal issue. The left foot drop, maybe
that's a neurologic issue. And then a rash on the elbows. So clearly a lot of different systems
are involved. Evidence of joint inflammation. At this point, it's not entirely clear, we'll need a
physical exam but she's not highlighting any joint pain or effusions at the moment. And next up,
systemic involvement. Well, the fevers and the weight loss certainly make us think about a systemic
involvement issue and of course she has 4 or 5 systems already involved just based on our HPI.
Now let's go into our physical exam. We do see that she has a temperature of 38.2°C so she is
in fact febrile. Heart rate is tachy at 102. Blood pressure looks okay and she is satting well
on room air. Normal sclera, no lymphadenopathy. The examiner does note some nasal polyps.
She's tachycardic. No murmurs, rubs, or gallops. And we do find some focal crackles up in the
right upper lung field. There is some dullness to percussion also at the left base. Something is
going on in multiple lung fields. Her abdomen reveals a soft, nondistended belly though she is
mildly tender over the epigastrium. And then in the neuromuscular exam, we find 3/5 strength
at the left ankle with dorsiflexion though 2+ reflexes throughout except 1+ at the left ankle.
Her skin and nail exam reveals some subcutaneous nodules with erythema and palpable purpura
on the bilateral arms at the extensor surfaces, a little bit more on the left than on the right.
That is a lot of data. So, which of the following is the most likely diagnosis? Is it eosinophilic
granulomatosis with polyangiitis? Is it granulomatosis with polyangiitis? Is it microscopic
polyangiitis? Is it anti-glomerular basement membrane disease? Or is it polyarteritis nodosa?
Poy, that is a lot of big words. Let's take a quick look at the classification of the vasculitides
so that we aren't completely loss in all of those syllables.