Adults
Palpable purpura / small-vessel vasculitis (adult)
Palpable purpura, especially with joint, gut, kidney or nerve involvement. Look for IgA vasculitis, cryoglobulins and ANCA.
What to look for
- Palpable, non-blanching purpura, usually on the legs
- Arthralgia, abdominal pain, hematuria or proteinuria, neuropathy
- Causes include IgA vasculitis, cryoglobulinemic vasculitis (often hepatitis C), drug-induced vasculitis, ANCA vasculitis and urticarial vasculitis
What to do
- Fever or a patient who looks unwell: treat as possible sepsis or endocarditis first, with same-day emergency assessment and blood cultures.
- Send urinalysis with microscopy, creatinine, CBC, ANCA, C3/C4, cryoglobulins (drawn and kept warm), hepatitis B and C, and HIV.
- Skin biopsy with direct immunofluorescence is most useful from a lesion less than 48 hours old.
- Kidney, gut or nerve involvement raises the urgency. Pulmonary-renal features are emergent.
About this urgency level
Early specialist assessment changes outcomes. Send the usual workup with the referral, but don't hold the referral while waiting for results.
Timeframes are typical targets. Local pathways, capacity and clinical judgment come first.