Types and Causes of PI1,2
There are more than 350 genetic disorders that can cause your immune system to not work like it should. Some of the more common types of PI include selective IgA deficiency, common variable immune deficiency (CVID), X-linked agammaglobulinemia (XLA), and severe combined immunodeficiency (SCID).
PI is different from secondary immunodeficiencies, which are caused by other conditions (such as diseases or consequences of certain types of medications), whereas PI is caused by a defect in the immune system, and can be inherited.
There's relief with diagnosis.
How Common Is PI?2-7
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. In fact, PI can affect 1 in over 1,200 people which is nearly as common as cystic fibrosis.
PI can impact anyone at any age and of either gender, but more than half (51%) of patients with PI are not diagnosed until >30 years of age. According to the 2007 IDF survey, a PI diagnosis can take about 12.4 years from the time symptoms begin.
One of the reasons it can be difficult to diagnose is because many PIs present as routine infections (i.e. sinus infections or pneumonia) and go undetected in multiple healthcare settings. PI is often mistaken for a variety of diseases/infections from skin rashes to diarrhea to noninfectious conditions such as allergies.
Testing for PI2
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.
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 discuss the different treatment options available and work with you to identify the treatment option that best meets your medical needs and personal preferences.
References: 1. Picard C, Gaspar HB, Al-Herz W, et al. International union of immunological societies: 2017 primary immunodeficiency diseases committee report on inborn errors of immunity. J Clin Immunol. 2018;38(1):96-128. 2. Blaese RM, Bonilla FA, Stiehm ER, Younger ME, eds. Patient & Family Handbook for Primary Immunodeficiency Diseases. 5th ed. Towson, MD: Immune Deficiency Foundation; 2013. 3. Mirtajani SB, Farnia P, Hassanzad M, Ghanavi J, Farnia P, Velayati AA. Geographical distribution of cystic fibrosis; The past 70 years of data analyzis. Biomed Biotechnol Res J. 2017;1:105-12. 4. About Primary Immunodeficiencies. Immune Deficiency Foundation website. https://primaryimmune.org/about-primary-immunodeficiencies/. Accessed June 12, 2019. 5. Immune Deficiency Foundation. Primary Immunodeficiency Diseases in America: 2007 The Third National Survey of Patients. Prepared by Abt. SRBI, Inc. May 2009. 6. de Vries E, Driessen G. Educational paper: primary immunodeficiencies in children: a diagnostic challenge. Eur J Pediatr. 2011;170(2):169-177. 7. Modell V, Gee B, Lewis DB, et al. Global study of primary immunodeficiency diseases (PI) - diagnosis, treatment, and economic impact: an updated report from the Jeffrey Modell Foundation. Immunol Res. 2011; 51(1):61-70.