Medicine & USMLE


  1. Selective IgA Deficiency
  2. Chediak-Higashi Syndrome
  3. DiGeorge Syndrome
  4. Bruton (X-linked) Agammaglobulinemia
  5. Hyper-IgM Syndrome
  6. IPEX
  7. Leukocyte Adhesion Deficiency (LAD)
  8. Chronic Granulomatous Disease (CGD)
  9. IL-12 Receptor Deficiency
  10. Wiskott-Aldrich Syndrome


IPEX is a severe X-linked immunodeficiency caused by a loss-of-function mutation in FOXP3. This impairs the development and function of Regulatory T-cells (Tregs). Loss of Treg function results in widespread immune dysregulation and autoimmune damage. Clinical features include immunodeficiency with recurrent infections, as well as autoimmune enteropathy, endocrinopathy and dermatitis.

Key Points

  • IPEX (Immune dysregulation, Polyendocrinopathy, Enteropathy, X-linked)
    • Genetic deficiency of FOXP3 leads to autoimmunity
    • Immunodeficiency
      • Recurrent infections secondary to immune dysregulation
    • X-linked Recessive
      • Generally affects male patients
    • Endocrinopathy
      • Including diabetes and thyroid disturbances, secondary to autoimmune damage
    • Enteropathy
      • Presents as diarrhea, secondary to autoimmunity against enterocytes
    • Dermatitis / Eczema
      • Secondary to autoimmune damage in skin