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Severe combined immunodeficiency due to FOXN1 deficiency

Disease definition

A rare, genetic, primary immunodeficiency due to a defect in adaptive immunity characterized by the triad of congenital athymia (resulting in severe T-cell immunodeficiency), congenital alopecia totalis and nail dystrophy. Patients present neonatal or infantile-onset, severe, recurrent, life-threatening infections and low or absent circulating T cells. Additional features reported include erythroderma, lymphoadenopathy, diarrhea and failure to thrive.


Classification level: Disorder
  • Synonym(s):
    • Alymphoid cystic thymic dysgenesis
    • Nude/SCID
    • Nude/severe combined immunodeficiency
    • SCID due to FOXN1 deficiency
    • Severe T-cell immunodeficiency-congenital alopecia-nail dystrophy syndrome
    • Winged helix deficiency
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal recessive or Autosomal dominant 
  • Age of onset: Infancy, Neonatal
  • ICD-10: D82.8
  • OMIM: 601705  618806
  • UMLS: -
  • MeSH: -
  • GARD: 4358
  • MedDRA: -

Detailed information


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