Types and Causes of PI
Some of the more common types of primary immunodeficiency (PI) include selective IgA deficiency, common variable immune deficiency (CVID), X-linked agammaglobulinemia (XLA), and severe combined immunodeficiency (SCID).1
PI is different from secondary immunodeficiencies, which are caused by other conditions (such as diseases or consequence of medication use), whereas PI is caused by a defect in the immune system, and can be inherited.1
There's relief with diagnosis.
How Common Is PI?
Primary immunodeficiency was once thought to be very rare, but now it is considered more common. As PI awareness with physicians continues to grow, more people are getting diagnosed.1 In a 2007 Immune Deficiency Foundation survey, it was estimated that a quarter million people in the United States have been diagnosed with PI,2 and the U.S. National Institutes of Health estimate that ~500,000 cases of PI remain undiagnosed.3
Testing for PI
When testing for PI, doctors will typically ask about your family history and do a physical exam. They may order blood tests to check if your red and white blood cells, antibodies, and immune system are working properly. These tests are important for your doctor to confirm a diagnosis of PI.1
If you have been diagnosed, these tests help determine which type of PI you may have. Once the tests are complete, and the PI diagnosis is confirmed, your doctor will recommend the best treatment options for your specific type of PI.
Early Diagnosis Is Important
If left untreated, chronic infections caused by PI can lead to organ damage, such as lung damage.1 People whose PI is discovered later in life may already have some permanent organ damage from previous infections. Immunoglobulin (Ig) replacement treatment cannot reverse any existing damage, but can reduce the number of infections.1
What Can I Do About PI?
If you have PI, there are medicines that can help. Keep reading to learn more about PI and your treatment options, and talk to your healthcare provider about what's right for you.
References: 1. Blaese RM, Bonilla FA, Stiehm ER, Younger ME, eds. Patient & Family Handbook for Primary Immunodeficiency Diseases. 5th ed. Towson, MD: Immune Deficiency Foundation; 2013. 2. Boyle JM, Buckley RH. Population prevalence of diagnosed primary immunodeficiency diseases in the United States. J Clin Immunol. 2007;27(5):497-502. 3. Modell F, Puente D, Modell V. From genotype to phenotype. Further studies measuring the impact of a Physician Education and Public Awareness Campaign on early diagnosis and management of primary immunodeficiencies. Immunol Res. 2009;44(1-3):132-149.
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