Kawasaki disease vs IgA vasculitis / polyarteritis nodosa
How to tell Kawasaki disease and IgA vasculitis / polyarteritis nodosa apart when a board question makes them look alike.
Kawasaki is fever plus mucocutaneous coronary-risk disease; IgA vasculitis is purpura-GI-renal disease; PAN is systemic medium-vessel ischemia.
Side by side
Child under 5 with at least 5 days of fever plus mucocutaneous inflammation: conjunctivitis, cracked lips or strawberry tongue, rash, extremity changes, and cervical lymphadenopathy.
IgA vasculitis gives palpable purpura, abdominal pain, arthralgia, and renal findings; PAN gives systemic medium-vessel ischemia such as abdominal pain, neuropathy, hypertension, or nodules.
Medium-vessel vasculitis targets coronary arteries and can form aneurysms if untreated.
IgA immune deposition inflames small vessels; PAN causes necrotizing medium-vessel arteritis with aneurysms and infarcts.
Prolonged fever with conjunctivitis, oral changes, extremity swelling/desquamation, and coronary aneurysm risk points Kawasaki.
Leg/buttock purpura with hematuria points IgA vasculitis; renal artery microaneurysms, neuropathy, and hepatitis B association points PAN.
The trap
Abdominal pain can appear in several vasculitides, so pair it with skin pattern, renal findings, and coronary risk.
Watch it explained
The repair move
For pediatric vasculitis, first decide whether the stem is coronary mucocutaneous disease, IgA purpura disease, or systemic medium-vessel ischemia.
Try a free question
CoreA 3-year-old has fever for 6 days, bilateral nonpurulent conjunctivitis, cracked lips, strawberry tongue, rash, swollen hands, and cervical lymphadenopathy. What complication is the main reason for prompt treatment?
Show answer and explanation
Answer: A. Coronary artery aneurysm. Kawasaki disease is a childhood medium-vessel vasculitis with mucocutaneous findings and coronary artery aneurysm risk.
Why the other choices are tempting
- B. IgA vasculitis can cause renal disease, but it does not cause the Kawasaki mucocutaneous pattern.
- C. PAN can involve renal arteries but is not defined by conjunctivitis, strawberry tongue, and extremity changes.
- D. Pulmonary hemorrhage points small-vessel pulmonary capillaritis such as MPA.
- E. Temporal artery vision loss points giant cell arteritis in older adults.
Flashcards
Tap a card to flip it.
What is the fastest separator for Kawasaki disease vs IgA vasculitis / polyarteritis nodosa?
Kawasaki is fever plus mucocutaneous coronary-risk disease; IgA vasculitis is purpura-GI-renal disease; PAN is systemic medium-vessel ischemia.
What clue should make you choose Kawasaki disease?
Child under 5 with at least 5 days of fever plus mucocutaneous inflammation: conjunctivitis, cracked lips or strawberry tongue, rash, extremity changes, and cervical lymphadenopathy.
Quick answers
What is the fastest way to tell Kawasaki disease from IgA vasculitis / polyarteritis nodosa?
Kawasaki is fever plus mucocutaneous coronary-risk disease; IgA vasculitis is purpura-GI-renal disease; PAN is systemic medium-vessel ischemia.
What is the key clue for Kawasaki disease?
Child under 5 with at least 5 days of fever plus mucocutaneous inflammation: conjunctivitis, cracked lips or strawberry tongue, rash, extremity changes, and cervical lymphadenopathy.
What is the key clue for IgA vasculitis / polyarteritis nodosa?
IgA vasculitis gives palpable purpura, abdominal pain, arthralgia, and renal findings; PAN gives systemic medium-vessel ischemia such as abdominal pain, neuropathy, hypertension, or nodules.
What is the common trap with Kawasaki disease vs IgA vasculitis / polyarteritis nodosa?
Abdominal pain can appear in several vasculitides, so pair it with skin pattern, renal findings, and coronary risk.