The very rare C6 deficiency (C6D) is caused by a homozygous or compound heterozygous mutation in the C6 gene (217050) on chromosome 5p13.
C6 deficiency, subtotal includedD84.1
DefinitionThis section has been translated automatically.
Occurrence/EpidemiologyThis section has been translated automatically.
Fukumori Y et al (1998) identified in Japan by screening for complement deficiencies in 145,640 blood donors from Osaka and in 92. 686 donors from all of Japan:
- 5 individuals with C5 deficiency (609536) (2/100,000).
- 6 persons with C6 deficiency (2.4/100,000)
- 17 individuals with C7 deficiency (610102)
- 5 individuals with C8 alpha/gamma deficiency (613790) (2/100,000)
- 439 individuals with C9 deficiency (613825).
Clinical featuresThis section has been translated automatically.
Both total C6 complement deficiency and subtotal C6 complement deficiency are described. Individuals with subtotal C6 deficiency have a C6 molecule that is 14% shorter than normal C6 and is present in low but detectable concentrations in serum (1 to 2% of normal average). Clinically, C6 deficiency is associated with severe bacterial (mainly N. meningitides) infections (Bae JY et al. 2020; Kernbaum S et al. 1980; Rauscher CK et al. 2020) as well as autoimmunological phenomena (arthritis, positive ANA, SLE-like symptoms) (Tedesco F et al. 1981).
LiteratureThis section has been translated automatically.
- Bae JY et al.(2020) Recurrent meningococcal meningitis with complement 6 (C6) deficiency: A case report. Medicine (Baltimore) 99: e20362.
- Fukumori Y et al. (1998) Terminal complement component deficiencies in Japan. Exp. Clin. Immunogenet. 15: 244-248.
- Kernbaum S et al (1980) Human deficiency of the sixth component of complement in a patient with meningococcal meningitis and no haemostasis abnormality. Biomedicine 33: 197-201.
- Rauscher CK et al (2020) Clinical implications of C6 complement component deficiency. Allergy Asthma Proc 41:386-388.
- Reinitz E et al (1986) Arthritis and antinuclear antibodies (ANA) with inherited deficiency of the sixth component of complement (C6). Ann Rheum Dis 45: 431-434.
- Tedesco F et al (1981) A lupus-like syndrome in a patient with deficiency of the sixth component of complement. Arthritis Rheum 24: 1438-1440.
- Vogler LB et al (1979) Recurrent meningococcal meningitis with absence of the sixth component of complement: an evaluation of underlying immunologic mechanism. Pediatrics 64: 465-467.