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Basics of immune deficiencies.

General information on immune deficiencies, and how they’re diagnosed and treated.

Immune deficiency is a broad category that includes more than 350 rare, chronic conditions. What these conditions all have in common is that at least one part of the immune system is either missing or doesn’t function properly, which prevents the immune system from effectively protecting the body against infection.

Immune deficiencies are inherited disorders, which means they are passed from parent to child. They are often diagnosed in children, but may appear at any age. People with immune deficiency are more prone to infections of the skin, sinuses, ears, lungs, spine, brain, gastrointestinal system and urinary system. These infections tend to be recurrent (occur repeatedly), are difficult to recover from, or are unusually severe.1


A doctor may suspect an immune deficiency if infections are:

  • Severe, requiring hospitalization or intravenous (IV) antibiotics
  • Persistent, taking a long time to clear up
  • Caused by a common organism that doesn’t often cause infections
  • Recurrent (keep coming back)
  • Common among family members

The doctor will take a detailed medical history, including information on infections, and conduct a physical exam. Laboratory tests are needed to confirm the diagnosis and confirm which specific condition the patient has.

One type of immune deficiency, severe combined immune deficiency (SCID), can be diagnosed through a screening test in infants. Finding this disorder early enables lifesaving interventions to be started before the infant is exposed to viruses or bacteria. Many states routinely screen infants for SCID.


Immune deficiency is often treated through immunoglobulin replacement therapy. Immunoglobulin (Ig) refers to the part of the blood that contains antibodies. To create the products used in Ig replacement therapy, plasma (the clear component of blood) is collected from many individuals with normal immune systems. The immunoglobulins are extracted from the plasma and chemically purified.

Ig replacement therapy helps to replace the missing pieces of the immune system – it does not stimulate the patient’s immune system to start producing the proteins on its own. Therefore, people with immune deficiency are usually on Ig therapy for their entire lives. It is typically given intravenously (into a vein) every three to four weeks. Often, the infusion can be done in the patient’s home.

If you have questions about your condition or treatment, call your doctor or contact your CVS Specialty CareTeam.

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1. Immune Deficiency Foundation, Accessed December 4, 2018.