IgG Deficiencies

Reviewed By:

What are IgG deficiencies?

An IgG deficiency is a health problem in which your body doesn’t make enough Immunoglobulin G (IgG). People with IgG deficiency are more likely to get infections. IgG deficiencies can occur at any age.

When your body feels it is under attack, it makes special proteins called immunoglobulins or antibodies. These antibodies are made by B cells and plasma cells. They are let loose throughout the body to help kill bacteria, viruses, and other germs. The body makes 4 major types of immunoglobulins:

  • Immunoglobulin A

  • Immunoglobulin G

  • Immunoglobulin M

  • Immunoglobulin E

Immunoglobulin G (IgG) is the most common type. IgG is always there to help prevent infections. It’s also ready to multiply and attack when foreign substances get into the body. When you don't have enough, you are more likely to get infections.

What causes IgG deficiencies?

It’s not known what causes IgG deficiency. However, genetics may play a role. Certain medications and other medical conditions can lead to IgG deficiency as well.

What are the symptoms of an IgG deficiency?

Infections that most often affect people with IgG deficiency are:

  • Sinus infections and other respiratory infections

  • Gastrointestinal infections

  • Ear infections

  • Pneumonia

  • Bronchitis

  • Infections that result in a sore throat

  • Rarely, severe and life-threatening infections

In some people, infections cause scarring that harms the airways and lung function. This can affect breathing. People with IgG deficiency also often find that pneumonia and the flu vaccines don’t keep them from getting these infections.

How is an IgG deficiency diagnosed?

A blood test that measures immunoglobulin levels is the initial step in diagnosing  IgG deficiency. More complicated but very important tests involve the measurement of antibody levels in response to certain vaccinations.

How is an IgG deficiency treated?

Treatment depends on how bad your symptoms and infections are. If infections are not getting in the way of your daily life, treating them right away may be enough. If you get frequent or severe infections that keep coming back, you may do well with ongoing treatment. This will help to prevent sickness or reduce symptoms or frequency. This may mean taking a daily antibiotic to ward off infections. You may need to alternate between other antibiotics if infections and symptoms still happen.

Some people who suffer from severe infections may need immunoglobulin therapy to help boost the body’s immune system rather than relying on antibiotics to prevent infections. Immunoglobulin therapy can be provided under the skin or in the veins.

When should I call my healthcare provider?

If you have been diagnosed with IgG deficiency, call your healthcare provider whenever you have signs of infection such as fever, chills or night sweats.

Key points

  • People with IgG deficiency are more likely to get infections.

  • Although it’s not known what causes IgG deficiency, genetics may play a role.

  • Blood tests help in diagnosing this condition.

  • Treatment depends on how bad your symptoms and infections are as well as the health of your immune system.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

  • Know the reason for your visit and what you want to happen.

  • Before your visit, write down the questions you want to be answered.

  • Bring someone with you to help you ask questions and remember what your provider tells you.

  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also, write down any new instructions your provider gives you.

  • Know why a new medicine or treatment is prescribed, and how it will help you. Also, know what the side effects are.

  • Ask if your condition can be treated in other ways.

  • Know why a test or procedure is recommended and what the results could mean.

  • Know what to expect if you do not take the medicine or have the test or procedure.

  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.

  • Know how you can contact your provider if you have questions.

Request an Appointment

Find a Doctor
Find a Doctor