Biopsy-proven kidney involvement in hypocomplementemic urticarial vasculitis

BMC Nephrol. 2022 Feb 16;23(1):67. doi: 10.1186/s12882-022-02689-8.


Background: Hypocomplementemic urticarial vasculitis (HUV) is a rare systemic vasculitis. We aimed to describe the kidney involvement of HUV in a multicenter national cohort with an extended follow-up.

Methods: All patients with HUV (international Schwartz criteria) with a biopsy-proven kidney involvement, identified through a survey of the French Vasculitis Study Group (FVSG), were included. A systematic literature review on kidney involvement of HUV was performed.

Results: Twelve patients were included, among whom 8 had positive anti-C1q antibodies. All presented with proteinuria, from mild to nephrotic, and 8 displayed acute kidney injury (AKI), requiring temporary haemodialysis in 2. Kidney biopsy showed membrano-proliferative glomerulonephritis (MPGN) in 8 patients, pauci-immune crescentic GN or necrotizing vasculitis in 3 patients (with a mild to severe interstitial inflammation), and an isolated interstitial nephritis in 1 patient. C1q deposits were observed in the glomeruli (n = 6), tubules (n = 4) or renal arterioles (n = 3) of 8 patients. All patients received corticosteroids, and 9 were also treated with immunosuppressants or apheresis. After a mean follow-up of 8.9 years, 6 patients had a preserved renal function, but 2 patients had developed stage 3-4 chronic kidney disease (CKD) and 4 patients had reached end-stage kidney disease (ESKD), among whom 1 had received a kidney transplant.

Conclusion: Renal involvement of HUV can be responsible for severe AKI, CKD and ESRD. It is not always associated with circulating anti-C1q antibodies. Kidney biopsy shows mostly MPGN or crescentic GN, with frequent C1q deposits in the glomeruli, tubules or arterioles.

Keywords: Anti-C1q antibody; C1q deposits; Glomerulonephritis; Hypocomplementemic urticarial vasculitis; McDuffie syndrome; Renal biopsy; Renal vasculitis.

Publication types

  • Multicenter Study
  • Systematic Review

MeSH terms

  • Adrenal Cortex Hormones / therapeutic use
  • Adult
  • Aged
  • Biopsy
  • Blood Component Removal
  • Child
  • Child, Preschool
  • Complement C1q / metabolism
  • Cyclophosphamide / therapeutic use
  • Female
  • Follow-Up Studies
  • Glomerulonephritis, Membranoproliferative / complications*
  • Glomerulonephritis, Membranoproliferative / drug therapy
  • Glomerulonephritis, Membranoproliferative / immunology
  • Glomerulonephritis, Membranoproliferative / pathology
  • Humans
  • Immunosuppressive Agents / therapeutic use
  • Male
  • Middle Aged
  • Retrospective Studies
  • Rituximab / therapeutic use
  • Syndrome
  • Urticaria / complications*
  • Urticaria / immunology
  • Vasculitis / complications*
  • Vasculitis / immunology


  • Adrenal Cortex Hormones
  • Immunosuppressive Agents
  • Rituximab
  • Complement C1q
  • Cyclophosphamide