What is an immunodeficiency disorder?

Key points

  1. Immunodeficiency disorders disrupt your body’s ability to defend itself against bacteria, viruses, and parasites.
  2. There are two types of immunodeficiency disorders: those you are born with (primary), and those that are acquired (secondary).
  3. Anything that weakens your immune system can lead to a secondary immunodeficiency disorder.

Immunodeficiency disorders prevent your body from fighting infections and diseases. This type of disorder makes it easier for you to catch viruses and bacterial infections.

Immunodeficiency disorders are either congenital or acquired. A congenital, or primary, disorder is one you were born with. Acquired, or secondary, disorders you get later in life. Acquired disorders are more common than congenital disorders.

Your immune system includes the following organs:

  • spleen
  • tonsils
  • bone marrow
  • lymph nodes

These organs make and release lymphocytes. These are white blood cells classified as B cells and T cells. B and T cells fight invaders called antigens. B cells release antibodies specific to the disease your body detects. T cells destroy foreign or abnormal cells.

Examples of antigens that your B and T cells might need to fight off include:

  • bacteria
  • viruses
  • cancer cells
  • parasites

An immunodeficiency disorder disrupts your body’s ability to defend itself against these antigens.

Read more: Fun facts about the immune system »

What are the different types of immunodeficiency disorders?

An immune deficiency disease occurs when the immune system is not working properly. If you are born with a deficiency or if there is a genetic cause, it is called primary immunodeficiency disease. There are more than 100 primary immunodeficiency disorders.

Examples of primary immunodeficiency disorders include:

  • X-linked agammaglobulinemia (XLA)
  • common variable immunodeficiency (CVID)
  • severe combined immunodeficiency (SCID), which is known as alymphocytosis or “boy in a bubble” disease

Secondary immunodeficiency disorders happen when an outside source like a toxic chemical or infection attacks your body. The following can cause a secondary immunodeficiency disorder:

  • severe burns
  • chemotherapy
  • radiation
  • diabetes
  • malnutrition

Examples of secondary immunodeficiency disorders include:

  • AIDS
  • cancers of the immune system, like leukemia
  • immune-complex diseases, like viral hepatitis
  • multiple myeloma (cancer of the plasma cells, which produce antibodies)

Who is at risk for immunodeficiency disorders?

People who have a family history of primary immunodeficiency disorders have a higher-than-normal risk for developing primary disorders.

Anything that weakens your immune system can lead to a secondary immunodeficiency disorder. For example, exposure to bodily fluids infected with HIV, or removing the spleen can be causes. Spleen removal may be necessary because of conditions like cirrhosis of the liver, sickle cell anemia, or trauma to the spleen.

Aging also weakens your immune system. As you age, some of the organs that produce white blood cells shrink and produce fewer of them.

Proteins are important for your immunity. Not enough protein in your diet can weaken your immune system. Your body also produces proteins when you sleep that help your body fight infection. For this reason, lack of sleep reduces your immune defenses. Cancers and chemotherapy drugs can also reduce your immunity.

The following diseases and conditions are linked to primary immunodeficiency disorders:

  • ataxia-telangiectasia
  • Chediak-Higashi syndrome
  • combined immunodeficiency disease
  • complement deficiencies
  • DiGeorge syndrome
  • hypogammaglobulinemia
  • Job syndrome
  • leukocyte adhesion defects
  • panhypogammaglobulinemia
  • Bruton’s disease
  • congenital agammaglobulinemia
  • selective deficiency of IgA
  • Wiskott-Aldrich syndrome

Signs of an immunodeficiency disorder

Each disorder has unique symptoms that can be frequent or chronic. Some of these symptoms can include:

  • pinkeye
  • sinus infections
  • colds
  • diarrhea
  • pneumonia
  • yeast infections

If these problems don’t respond to treatment or you don’t completely get better over time, your doctor might test you for an immunodeficiency disorder.

How are immune disorders diagnosed?

If your doctor thinks you might have an immunodeficiency disorder, they will want to do the following:

  • ask you about your medical history
  • perform a physical exam
  • determine your white blood cell count
  • determine your T cell count
  • determine your immunoglobulin levels

Vaccines can test your immune system response in what is called an antibody test. Your doctor will give you a vaccine. Then they will test your blood for its response to the vaccine a few days or weeks later.

If you don’t have an immunodeficiency disorder, your immune system will produce antibodies to fight the organisms in the vaccine. You might have a disorder if your blood test doesn’t show antibodies.

How are immunodeficiency disorders treated?

The treatment for each immunodeficiency disorder will depend on the specific conditions. For example, AIDS causes several different infections. Your doctor will prescribe medications for each infection. And you may be given an antiretroviral to treat and HIV infection if appropriate.

Treatment for immunodeficiency disorders commonly includes antibiotics and immunoglobulin therapy. Other antiviral drugs, amantadine and acyclovir, or a drug called interferon are used for treatment of the viral infections caused by immunodeficiency disorders.

If your bone marrow isn’t producing enough lymphocytes, your doctor might order a bone marrow (stem cell) transplant.

How can immunodeficiency disorders be prevented?

Primary immunodeficiency disorders can be controlled and treated, but they can’t be prevented.

Secondary disorders can be prevented in a number of ways. For example, it’s possible to prevent yourself from getting AIDS by not having unprotected sex with someone who carries HIV.

Sleep is very important for a healthy immune system. According to the Mayo Clinic, adults need about eight hours of sleep per night. It’s also important that you stay away from people who are sick if your immune system isn’t working properly.

If you have a contagious immunodeficiency disorder like AIDS, you can keep others healthy by practicing safe sex and not sharing bodily fluids with people who aren’t infected.

What is the outlook for someone with an immunodeficiency disorder?

Most doctors agree that people with immunodeficiency disorders can lead full and productive lives. Early identification and treatment of the disorder is very important.

You asked, we answered

  • I have a family history of immunodeficiency disorders. If I have children, how early should they be screened for it?
  • A family history of primary immunodeficiency is the strongest predictor of a disorder. At birth and for only a few months, babies are partially protected from infections by antibodies transmitted to them by their mothers. Typically, the earlier the age at onset of signs of an immunodeficiency in children, the more severe the disorder. Testing can be done within the first few months, but it is also important to recognize the early signs: recurrent infections and failure to thrive. Initial laboratory screening should include a complete blood count with differential and measurement of serum immunoglobulin and complement levels.

    - Brenda B. Spriggs, MD, FACP