Types of primary immunodeficiency

Over 300 different primary immunodeficiencies (PIDs) have been identified, with about 20 of these accounting for over 90 per cent of cases. This means that many conditions are extremely rare: indeed for some conditions, fewer than ten cases have been identified.

Classification of PIDs

Every two years an international committee of experts meets to revise and update this classification, adding new conditions and information on the genes that cause PIDs.

At present, PIDs are grouped or classified under eight major subcategories based on what cells or parts of the immune system are affected.

These subcategories are:

  • Combined immunodeficiencies including conditions such as X-linked severe combined immunodeficiency (X-SCID) and adenosine deaminase (ADA) deficiency.
  • Diseases of immune dysregulation including conditions such as ChediakHigashi syndrome and X-linked lymphoproliferative syndrome (XLP).
  • Defects in innate immunity including conditions such as NEMO deficiency.
  • Autoinflammatory disorders such as MuckleWells syndrome and Blau syndrome.
  • Complement deficiencies

You can download the 2017 list of known primary immunodeficiencies here.

This page was reviewed by the Medical Advisory Panel, May 2013.