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Overview of Immunodeficiency Disorders


The Manual's Editorial Staff

Last full review/revision Sep 2019
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The immune system is your body's defense system. It helps protect you from illness and infection. The immune system's job is to attack things that don’t belong in your body, such as germs, parasites, and cancer cells.

What is an immunodeficiency disorder?

Immunodeficiency means a weak (deficient) immune system. People with immunodeficiency are sometimes said to be immunosuppressed or immunocompromised.

Your sicknesses may last longer than other people's, and what is a mild infection for other people may make you severely sick.

  • With a weak immune system, you're not protected well from illness and infection

  • You'll get sick more often than normal

  • Common infections may be more dangerous, and you may get unusual infections

  • You may be born with immunodeficiency or get it from an infection, disease, or medical treatment

  • If you have immunodeficiency, you'll need to do things to avoid getting an infection

  • Doctors treat illnesses caused by immunodeficiency with antibiotics, immune globulin, and sometimes stem cell transplantation

What causes an immunodeficiency disorder?

Immunodeficiency disorders can be caused by:

  • A genetic disorder you're born with—though this is rare

  • An infection such as AIDS

  • Certain cancers, particularly cancers that affect your bone marrow

  • Cancer treatments such as radiation therapy and some chemotherapy

  • Certain drugs

Many drugs that doctors use to block inflammation can weaken your immune system. Such drugs are called immunosuppressants. An example is a corticosteroid drug, like prednisone. Sometimes doctors give you immunosuppressants because your immune system is attacking your own body (an autoimmune disorder).

What are the symptoms of an immunodeficiency disorder?

Symptoms include:

How can doctors tell if I have an immunodeficiency disorder?

Doctors suspect an immunodeficiency disorder if you're sick a lot, your sicknesses are more severe, or you don't respond normally to treatment. They usually do:

  • Blood tests

Blood tests may show a very low white blood cell count or low levels of substances made by your immune system. You'll be given an HIV test if you have risk factors for HIV infection. If your child has signs of immunodeficiency doctors may do genetic testing.

Depending on your symptoms, doctors may also do:

  • Skin tests that tell how your immune system is working

  • Biopsy of any swollen lymph nodes (swollen glands) or sometimes your bone marrow

How do doctors treat immunodeficiency disorders?

Doctors treat the disorder, such as cancer, diabetes, or HIV infection, that is causing your immunodeficiency. Successful treatment usually improves your immune system.

If a medicine you're taking causes immunodeficiency, doctors may decrease the dose or have you stop taking it. Doctors will consider how much you need the medicine and how bad the immunodeficiency is while deciding whether to decrease or stop the medicine.

If immunodeficiency has caused an infection, doctors may give you:

  • Antibiotics

  • Immune globulin (antibodies from the blood of people with a healthy immune system)

If your immunodeficiency disorder is caused by a bone marrow problem, doctors may do:

Stem cells are cells that develop into blood cells, including the white blood cells that fight infection. Doctors can get stem cells from healthy people and give them to you in an IV. The stem cells can go to your bone marrow and start to make healthy white blood cells.

How do I prevent infections if I have immunodeficiency?

You should try to avoid infections by:

  • Avoiding contact with sick people

  • Getting all the vaccinations (shots) your doctor recommends

  • Avoiding undercooked food, or water that may not be clean

If you start to get sick, you should check with your doctor even if it doesn't seem too serious.

Drugs Mentioned In This Article

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Gammagard S/D
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