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Hypocomplementemic urticarial vasculitis

Disease definition

A rare immune complex-mediated small vessel vasculitis characterized by urticaria and hypocomplementemia (low C3, C4 and/or C1q), and usually associated with circulating anti-C1q autoantibodies. Arthritis, pulmonary disease, ocular inflammation are common systemic manifestations.


Classification level: Disorder
  • Synonym(s):
    • Anti-C1q vasculitis
    • Mac Duffie hypocomplementemic urticarial vasculitis
    • Mac Duffie syndrome
    • McDuffie hypocomplementemic urticarial vasculitis
    • McDuffie syndrome
  • Prevalence: Unknown
  • Inheritance: Autosomal recessive or Not applicable 
  • Age of onset: Adult, Childhood
  • ICD-10: M31.8
  • OMIM: -
  • UMLS: -
  • MeSH: -
  • GARD: 6725
  • MedDRA: -

Detailed information


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