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About Primary
Immunodeficiency (PI)

What is Primary Immunodeficiency?

A person with primary immunodeficiency (PI) has an immune system that doesn't function correctly, because one or more organs, tissues, cells, or proteins is missing or malfunctioning. The condition is usually inherited, and is caused by errors in genes that serve as a blueprint for forming the immune system.1

What are the symptoms of PI?

Your immune system protects your body from germs like bacteria and viruses. So, if part of your immune system is missing or not functioning correctly, you'll be more likely to get infections, you may take longer to recover, even with antibiotics, and you may have recurring infections. These symptoms can often be seen early in a child's life. However, signs of immune deficiency may also occur in older children, teenagers, or adults.1

Are there different types of PI?

The World Health Organization currently lists over 150 different types of PI2, ranging from mild to severe. Some types of primary immunodeficiency are characterized by low levels of antibodies. Others involve defects in T cells, B cells, granulocytes or the complement system. Because of these differences, individuals with different types of PI are susceptible to different types of diseases.1

How is PI diagnosed?

To diagnose primary immunodeficiency, doctors generally do a physical exam, ask about family history, and order blood and skin tests. These tests check total numbers and functioning of red and white blood cells, antibodies, T cells and complement system. The test results help doctors determine the type of PI and recommend a treatment protocol.1

Is PI contagious?

Unlike acquired immune deficiency syndrome (AIDS), primary immunodeficiency is not caused by a virus and is not contagious. It is a genetic disease that is present from birth. Although symptoms may not be apparent until later in life, it is not transferred from one person to another by close contact.1

How is PI treated?

Because many people with PI lack antibodies needed to resist infection, they can benefit from the infusion of additional antibodies, also known as intravenous immunoglobulin therapy (IVIG). For the types of PI which don't benefit from IVIG, there are other treatments available, including antibiotics, stem cell transplants, granulocyte-colony stimulating factor (G-CSF), gamma interferon, and PEG-ADA. Your doctor will help you determine what's right for you.1

Name _____________________ Type of PI ________________________________

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  1. Blaese RM, Winkelstein J. Patient & Family Handbook for Primary Immunodeficiency Diseases. Towson, MD: Immune Deficiency Foundation; 2007.
  2. Geha R, Notarangelo L, Casanova JL, Conley ME, Chapel ME, Fischer A, Hammerstrom L, Nonoyama S, Ochs H, Puck J, Roifman C, Seger R, Wedgwood J. Primary immunodeficiency diseases: an update from the International Union of Immunological Societies Primary Immunodeficiency Diseases Classification Committee Meeting. Journal of Allergy and Clinical Immunology 2007; 120(4):776-794.