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Immunodeficiency by defective expression of HLA class 2

Disease definition

Immunodeficiency by defective expression of HLA class 2 is a rare primary genetic immunodeficiency disorder characterized by partial or complete absence of human leukocyte antigen class 2 expression resulting in severe defect in both cellular and humoral immune response to antigens. The disorder presents clinically as marked susceptibility to infections, severe malabsorption and failure to thrive and is often fatal in early childhood.


  • Synonym(s):
    • Bare lymphocyte syndrome type 2
    • HLA class 2-negative SCID
    • HLA class 2-negative severe combined immunodeficiency
    • MHC class II expression deficiency
    • Major histocompatibility complex class II expression deficiency
  • Prevalence: Unknown
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Neonatal
  • ICD-10: D81.7
  • OMIM: 209920
  • UMLS: C2931418
  • MeSH: -
  • GARD: 824
  • MedDRA: -

Additional information

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