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Primary Immunodeficiency

What is Primary Immunodeficiency?

Your immune system keeps you healthy by fighting off germs. But people living with primary immunodeficiency disease (PID, sometimes known as PI or PIDD) have an immune system that is not working properly, beginning at birth. For people living with PID, infections may not go away or can come back often, even with the use of antibiotics. Infections may be common, severe, long-lasting, or hard to cure, but once correctly diagnosed and treated, people with PID can live full and active lives.

Microscopic view of primary immunodeficiency disease

Primary Immunodeficiency Explained

Every day, the human immune system fights off countless infections from viruses, bacteria and other organisms. For many people with primary immunodeficiency disease (PI), that protection isn’t always available due to a defect in one of the functions of the body’s normal immune system.

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PI Patient Ben Davies

How is Primary Immunodeficiency diagnosed?

If you believe you might have PID, the first step is to get an expert evaluation. An immune system specialist, called an immunologist, can help with diagnosis and treatment. When an immunologist evaluates your immune system, the evaluation may include: a detailed medical history, a physical exam, blood tests and vaccines to test your immune response.

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