What Primary Immunodeficiency Is Not
Primary immunodeficiency should not be confused with autoimmune disorders or secondary immunodeficiencies. In an autoimmune disorder (like rheumatoid arthritis or Type 1 diabetes), the immune system gets confused and attacks the body.9
With secondary immunodeficiency, something else causes the immune system to not work right, like another infection or a medical treatment (such as chemotherapy). The most common type of secondary immunodeficiency is AIDS, which is caused by the human immunodeficiency virus (HIV).7
With primary immunodeficiency, a part of the immune system is either missing or not working correctly. Primary immunodeficiency diseases are mainly genetic defects that may be inherited.7
PI should not be confused with autoimmune disorders or secondary immunodeficiencies.
How Many People Have Primary Immunodeficiency?
Though they were once thought to be rare, primary immunodeficiencies, as a group, are now considered more common.6 As PI awareness among physicians continues to grow and better diagnostic tools are available, more people are getting diagnosed.6
In a 2007 Immune Deficiency Foundation (IDF) survey, it was estimated that a quarter million people in the United States have been diagnosed with PI, and many more have not yet been diagnosed.10,11 The National Institutes of Health (NIH) estimates that at least half a million people have PI in the United States.12
Primary Immunodeficiency Symptoms and Diagnosis
Susceptibility to infections is one of the most common symptoms of PI.8 However, the symptoms can vary, and they can be mistaken for common infections, since even healthy people without PI can get sick frequently.8
Once thought to be a child's disease, we now know that PI can be diagnosed at any age.7 When testing for PI, doctors will ask about your family history and do a physical exam. They will also order blood and skin tests to check if your blood cells, antibodies, and immune system are working properly. These tests are important for your doctor to confirm a diagnosis of PI and to determine the type of PI you have.7
Download these 10 Warning Signs of PI from the Jeffrey Modell Foundation.
Treating Primary Immunodeficiency
If left untreated, PI can lead to recurring infections.7 However, there are several medical treatments available to help people with PI manage their condition. Talk to your doctor to choose the treatment that is best for you.