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Immunodeficiency by defective expression of MHC class I

Disease definition

A rare autosomal recessive primary immunodeficiency characterized by severe reduction in the cell surface expression of HLA class I molecules, typically resulting in childhood-onset of chronic bacterial infections of the respiratory tract evolving to widespread bronchiectasis and respiratory insufficiency. Sterile necrotizing granulomatous skin lesions mainly involving the extremities and the mid-face may be observed in some patients. Severe viral infections do not occur as part of the condition. Atypical variants without respiratory or cutaneous manifestations, as well as asymptomatic individuals have been reported.


Classification level: Disorder
  • Synonym(s):
    • Bare lymphocyte syndrome type 1
    • MHC class I deficiency
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Childhood
  • ICD-10: D81.6
  • ICD-11: 4A01.11
  • OMIM: 241600  604571
  • UMLS: C1858266
  • MeSH: -
  • GARD: 8427
  • MedDRA: -
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