What is IgA deficiency?

Immunoglobulin A (IgA) is an antibody blood protein that’s part of your immune system. Your body makes IgA and other type of antibodies to help fight off sickness. Having an IgA deficiency means that you have low levels of or no IgA in your blood. 

IgA is found in mucous membranes, mainly in the respiratory and digestive tracts. It is also found saliva, tears, and breastmilk. A deficiency seems to play a part in asthma and allergies. Researchers have also linked IgA deficiency to autoimmune health problems. These are health problems that cause your body’s immune system to attack your body by mistake.

What causes IgA deficiency?

IgA deficiency is a health problem that is passed down through families in about 1 in 5 cases. This means it is genetic. In rare cases, it can be caused by medicines you are taking.

What are the symptoms of IgA deficiency?

Most people with an IgA deficiency don’t have any symptoms of the health problem. It’s usually found on a blood test, if it’s found at all. About 1 in 4 to 1 in 2people with selective IgA deficiency will be affected. Some people with an IgA deficiency are more likely to get frequent infections. These can include sinus, lung, and digestive infections. Some people with IgA deficiency also are more likely to have allergies, and digestive and autoimmune problems such as celiac disease or lupus. 

How is IgA deficiency diagnosed?

If IgA deficiency runs in your family or you have some of the above symptoms, you might be at risk. Blood tests can be used to see if IgA is missing in your blood.

How is IgA deficiency treated?

There is no cure for IgA deficiency. Immunotherapy does not work to treat it. But you can take steps to lower your risk for illness or infection. These include taking antibiotics when you get sick. If infections are ongoing (chronic), you may need to take antibiotics every day.

What are the complications of IgA deficiency?

Potential complications can include:

• Diarrhea
• Sinusitis
• Bronchitis
• Eye infection
• Ear infection
• Pneumonia
• Autoimmune disorders
• Skin infection
• Asthma
• Allergic reactions to blood or blood product transfusions

Can IgA deficiency be prevented?

IgA deficiency is a problem that may be passed down through your family, so you can’t do anything to prevent it. But you can limit the spread of germs and sickness by washing your hands often and staying away from large crowds. This is especially true during cold and flu season. Also talk with your healthcare provider about vaccines that may help prevent illness and when you should get them.

If you have IgA deficiency and are worried about the risks of passing it on to your children, talk with a genetic counselor. 

Key points

• Immunoglobulin A (IgA) is an antibody that’s part of your immune system. IgA is found in mucous membranes, especially in the respiratory and digetive tracts. It is also found in saliva, tears, and breastmilk.
• IgA deficiency is a genetic health problem that can be passed down through families.
• Most people with an IgA deficiency don’t have any symptoms.
• There is no cure for IgA deficiency. Immunotherapy does not work to treat it.
• Complications for IgA deficiency include asthma, diarrhea, ear and eye infections, autoimmune diseases, and pneumonia.
• You can limit the spread of germs and illnesses by washing your hands often and staying away from large crowds.

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 questions you want 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.