Primary immunodeficiency diseases (PI) are a group of more than 250 rare, chronic disorders in which part of the body’s immune system is missing or functions improperly. While not contagious, these diseases are caused by hereditary or genetic defects, and, although some disorders present at birth or in early childhood, the disorders can affect anyone, regardless of age or gender. Some affect a single part of the immune system; others may affect one or more components of the system.
And while the diseases may differ, they all share one common feature: each results from a defect in one of the functions of the body’s normal immune system. Because one of the most important functions of the normal immune system is to protect us against infection, patients with PI commonly have an increased susceptibility to infection.
The infections may be in the skin, the sinuses, the throat, the ears, the lungs, the brain or spinal cord, or in the urinary or intestinal tracts, and the increased vulnerability to infection may include repeated infections, infections that won’t clear up or unusually severe infections. People with PI live their entire lives more susceptible to infections–enduring recurrent health problems and often developing serious and debilitating illnesses. Fortunately, with proper medical care, many patients live full and independent lives.
If any of these words describe your infection, the Immune Deficiency Foundation (IDF) recommends that you ask your physician to check for the possibility of PI.
Click here to read more about specific types of PI. If you have further questions, please contact IDF through Ask IDF or call 800-296-4433.
IUIS Classification of Primary Immunodeficiencies
In April 2014, the Expert Committee of the International Union of Immunological Societies (IUIS) updated the classification of primary immunodeficiencies. In comparison to the previous version, more than 30 new gene defects are reported in this updated version. This classification is the most up-to-date catalog of all known primary immunodeficiencies and acts as a current reference of the knowledge of these conditions and is an important aid for the molecular diagnosis of patients with these rare diseases. Click here to download the article.