Inaugural Clinical Problem Solving/ Razor Case: Polyarteritis Nodosa

Thanks to Sima Desai, Ken Scalapino, Joe Chiovaro, Claire Zeigler, Amarprit Bains, Joel Papak, Adam Obley, Alan Hunter, Joe Shatzel, Rebecca Harrison, and Kyle Kent for attending our first Clinical problem solving/ Razor case and their numerous pearls! And thanks to André Mansoor, APDs, Yale colleagues (Maximilian Stahl, Anne Liu and Pranay Sinha) for their advice and assistance.

This was a case of a young person with CAD risk factors, and recurrent presentations of arterial ischemia/ thrombosis who was ultimately diagnosed with polyarteritis nodosa.


This case highlighted some excellent pearls regarding clinical decision making:

  1. ) It is important to be cost conscious and thoughtful about ordering expensive diagnostic tests, but that the same time in a patient who is critically ill and may not re-present to the hospital, it is important to think more broadly and reasonable to order a broader panel of tests. Ultimately in order to practice cost conscious care, we must practice excellent diagnostic reasoning and ask how each test will change our decision making. Here is a great recent JAMA viewpoint about this.
  2. ) We discussed more "cost conscious" ways of ordering rheumatology studies (eg. consider ordering an ANA as a screening test before diving into an ENA panel and consider ordering only ESR or CRP and thinking about how the result would change management).
  3. ) A diagnosis of APLA rests on using the 2006 Sapporo criteria which include: a panel of tests (lupus anticoagulant, anti-cardiolipin and anti-beta2 glycoprotein) that need to be ordered and reconfirmed 12 weeks later, as well as evidence of thrombi or first trimester pregnancy loss.

Want to learn more?

Acute Limb ischemia

  • Remember that the most likely cause by far is atherosclerotic disease or cardiogenic emboli
  • In patients with multiorgan involvement and arterial thrombi it is important to consider more rare etiologies such as familial/ genetic conditions (including vasculopathies, CTD, hypercholesterolemia, thrombophilia), endocarditis, and vasculitis.
  • Here is a nice table that outlines the severity of limb ischemia by stage as well as a great NEJM article regarding evaluation and treatment of acute limb ischemia
  • Here is an article that was recommended by Joe Shatzel that he published on cryptogenic acute limb ischemia

Polyarteritis nodosa

  • This is a very rare vasculitis leading to necrotizing inflammation of medium sized arteries that presents with multiorgan involvement
  • Sometimes patients with this condition may be misidentified as drug seeking given their episodes of pain such as recurrent presentations to the ED for abdominal pain
  • The ACR has criteria that can aid in diagnosis but overall this is a clinical diagnosis that should be entertained when other causes of arterial thrombi have been ruled out
  • A quick literature search by Alan Hunter revealed that he did not find a specific connection between PAN and clubbing/ periungual erythema
  • Treatment involves close follow up with our rheumatology colleagues, steroids and immunosuppressants