Vasculitic purpura in adults (suspected vasculitis)
BioMG follows French guidelines. Adapt it to the guidelines and the tests available where you practise.
Vasculitic purpura without fever, normal platelets: initial tests
- Febrile purpura: page "Purpura, ecchymoses, saignements" (purpura fulminans, absolute emergency).
Laboratory tests
- FBC with platelets
- CRP
- Serum creatinine with eGFR
- ANCA (immunofluorescence, then anti-MPO and anti-PR3 specificity if positive)
- Antinuclear antibodies (ANA)
- Rheumatoid factor
- Cryoglobulin screen (sample kept at 37 °C until it reaches the laboratory)
- Complement: CH50, C3, C4
- Serum protein electrophoresis
- Hepatitis B serology (HBsAg, anti-HBc, anti-HBs)
- Hepatitis C serology
- HIV serology
- Blood cultures (fever, heart murmur)if neededFever, or even routinely, to rule out infective endocarditis, which can be accompanied by ANCA [1].
- ASTif needednon-French guidelineSigns associated with systemic involvement (nausea or vomiting, abdominal pain, fatigue, ulcerated or necrotic lesions, haematuria) or persistent or recurrent form: a 2026 American review then asks for a full metabolic panel with FBC, ESR or CRP and urine tests [2]; a 2022 mini-review has liver function tests measured in every patient suspected of vasculitis [3]. The French PNDS places it in the pre-treatment work-up, once ANCA vasculitis is established [1].
- ALTif needednon-French guidelineSigns associated with systemic involvement (nausea or vomiting, abdominal pain, fatigue, ulcerated or necrotic lesions, haematuria) or persistent or recurrent form: a 2026 American review then asks for a full metabolic panel with FBC, ESR or CRP and urine tests [2]; a 2022 mini-review has liver function tests measured in every patient suspected of vasculitis [3]. The French PNDS places it in the pre-treatment work-up, once ANCA vasculitis is established [1].
Urine tests
- Urine dipstick (haematuria, proteinuria)
- Urine protein:creatinine ratio (spot sample)
- Not a laboratory test: skin biopsy; opinion of an internist or dermatologist.
Also consider
Do not order
- ANCA other than anti-MPO and anti-PR3 (anti-elastase, anti-lactoferrin, anti-BPI, anti-cathepsin G): no clinical relevance [1].
IgA vasculitis (Henoch-Schönlein purpura) in adults: renal monitoring
At diagnosis
- Urine dipstick (haematuria, proteinuria)
- Urine protein:creatinine ratio (spot sample)
- Serum creatinine with eGFR
Sources (11)
- Haute Autorité de santé, Groupe français d'étude des vascularites, filière FAI²R. Protocole national de diagnostic et de soins (PNDS) : vascularites associées aux ANCA. Janvier 2026 (et synthèse à destination du médecin traitant).
- Seiter D, Del Rosso JQ. Fundamentals of Dermatology Article Series: When Is Cutaneous Vasculitis “More Than Just a Rash”? J Clin Aesthet Dermatol. 2026;19(6):49-51.
- Alpsoy E. Cutaneous vasculitis; An algorithmic approach to diagnosis. Front Med (Lausanne). 2022;9:1012554.
- Bossuyt X, Cohen Tervaert JW, Arimura Y, et al. Position paper: Revised 2017 international consensus on testing of ANCAs in granulomatosis with polyangiitis and microscopic polyangiitis. Nat Rev Rheumatol. 2017;13(11):683-692.
- Assurance maladie. Nomenclature des actes de biologie médicale (NABM), version 105 : actes 1462 et 1463 (ANCA), 1573 (cryoglobulines), 1571 (immunofixation).
- Ferri C, Gragnani L, Zignego AL, Giuggioli D. Cryoglobulinemia, monoclonal and mixed cryoglobulinemia syndromes, cryoglobulinemic vasculitis: a proposal for comprehensive nomenclature and definition. Front Immunol. 2026;17:1754012.
- Alpsoy E, Caproni M, Wetter DA, et al. Recommendations for the diagnostic work-up of cutaneous small vessel vasculitis - Position Statement of the European Academy of Dermatology and Venereology Vasculitis and Vasculopathy Task Force. J Eur Acad Dermatol Venereol. 2026;40(6):946-962.
- Hellmich B, Sanchez-Alamo B, Schirmer JH, et al. EULAR recommendations for the management of ANCA-associated vasculitis: 2022 update. Ann Rheum Dis. 2024;83(1):30-47.
- Kidney Disease: Improving Global Outcomes (KDIGO) ANCA Vasculitis Work Group. KDIGO 2024 Clinical Practice Guideline for the Management of Antineutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis. Kidney Int. 2024;105(3S):S71-S116.
- Biddle K, Jade J, Wilson-Morkeh H, et al. The 2025 British Society for Rheumatology management recommendations for ANCA-associated vasculitis. Rheumatology (Oxford). 2025;64(8):4470-4494.
- Kidney Disease: Improving Global Outcomes (KDIGO) IgAN and IgAV Work Group. KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV). Kidney Int. 2025;108(4S):S1-S71.