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Immunodeficiency due to a classical component pathway complement deficiency

Disease definition

Immunodeficiency due to a classical component pathway complement deficiency is a primary immunodeficiency due to a deficiency in either complement components C1q, C1r, C1s, C2 or C4 characterized by increased susceptibility to bacterial infections, particularly with encapsulated bacteria, and increased risk for autoimmune disease. Most commonly, these include systemic lupus erythematosus (SLE), SLE-like disease, Henoch-Schonlein purpura, polymyositis and arthralgia. Disease severity is variable and dependent on the complement affected.


Classification level: Disorder
  • Synonym(s):
    • Immunodeficiency due to C1, C4, or C2 component complement deficiency
    • Immunodeficiency due to an early component of complement deficiency
  • Prevalence: -
  • Inheritance: -
  • Age of onset: -
  • ICD-10: D84.1
  • ICD-11: 4A00.10
  • OMIM: 216950  217000  613652  613783  614379  614380
  • UMLS: -
  • MeSH: -
  • GARD: -
  • MedDRA: -
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.