Henoch-Schonlein purpura vs Other vasculitides in children
How to tell Henoch-Schonlein purpura and Other vasculitides in children apart when a board question makes them look alike.
Step 2 CK pairs are in open beta while clinical review finishes. Spot an issue? Tell us.
Palpable purpura with a normal platelet count in a child with abdominal pain identifies IgA vasculitis.
Side by side
Palpable purpura on the buttocks and legs with abdominal pain and arthralgia after an upper respiratory infection points to IgA vasculitis.
Persistent fever with mucosal inflammation, coronary findings, or purpura with thrombocytopenia suggests a different pediatric vasculitis syndrome.
Immune complex deposition with IgA in small vessels causes skin, joint, gut, and renal inflammation.
Other pediatric vasculitides use different immune pathways such as medium-vessel inflammation in Kawasaki disease or antiplatelet-associated vascular injury in meningococcemia.
Urinalysis often shows hematuria and proteinuria with normal platelet count, ESR may be elevated, and skin biopsy shows leukocytoclastic vasculitis with IgA deposition.
Alternative causes are suggested by platelets below 150000 per uL with purpura, CRP above 3 mg/dL plus prolonged fever and mucosal changes in Kawasaki disease, or positive blood culture in septic vasculitic mimics.
The trap
Students label any childhood purpura as IgA vasculitis and miss dangerous mimics. A platelet count below normal, hypotension, or toxic appearance should redirect toward sepsis, ITP, or other vasculitis rather than supportive-only IgA care.
The repair move
Next best step: obtain urinalysis, serum creatinine, and blood pressure assessment to stage renal involvement, then start supportive care with hydration and analgesia. If severe abdominal or joint pain persists, give prednisone 1 mg/kg/day for a short course and arrange close renal follow-up for persistent hematuria or proteinuria.
Try a free question
CoreA 6-year-old girl develops palpable purpura on both legs, ankle arthralgia, and crampy abdominal pain after a sore throat. BP 108/66 mm Hg, HR 92/min, temp 37.4 C. Platelets are 301000 per uL, creatinine is normal, and urinalysis shows microscopic hematuria. What is the next best step in management?
Show answer and explanation
Answer: A. Supportive care with hydration, analgesia, and renal monitoring. Classic IgA vasculitis without instability is managed supportively with structured renal follow-up.
Why the other choices are tempting
- B. IVIG is used for Kawasaki disease or immune thrombocytopenia, not uncomplicated IgA vasculitis.
- C. Platelet transfusion is not indicated because platelet count is normal and bleeding is vasculitic, not thrombocytopenic.
- D. Meningococcemia is less likely without fever, toxicity, hypotension, or thrombocytopenia.
- E. Cyclophosphamide is reserved for severe crescentic nephritis, not first-line care in this presentation.
Flashcards
Tap a card to flip it.
Which finding in a child with purpura most strongly supports IgA vasculitis rather than thrombocytopenic purpura?
Palpable lower-extremity purpura with a normal platelet count and associated abdominal pain or arthralgia supports IgA vasculitis.
What renal screening should be done at diagnosis of Henoch-Schonlein purpura?
Check urinalysis for hematuria or proteinuria, blood pressure, and serum creatinine to detect nephritis early.
Quick answers
What is the fastest way to tell Henoch-Schonlein purpura from Other vasculitides in children?
Palpable purpura with a normal platelet count in a child with abdominal pain identifies IgA vasculitis.
What is the key clue for Henoch-Schonlein purpura?
Palpable purpura on the buttocks and legs with abdominal pain and arthralgia after an upper respiratory infection points to IgA vasculitis.
What is the key clue for Other vasculitides in children?
Persistent fever with mucosal inflammation, coronary findings, or purpura with thrombocytopenia suggests a different pediatric vasculitis syndrome.
What is the common trap with Henoch-Schonlein purpura vs Other vasculitides in children?
Students label any childhood purpura as IgA vasculitis and miss dangerous mimics. A platelet count below normal, hypotension, or toxic appearance should redirect toward sepsis, ITP, or other vasculitis rather than supportive-only IgA care.