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Some Types of PI:

Selective Immunoglobulin A (IgA) Deficiency

While there are over 450 different types of PI, selective IgA deficiency is defined by low immunoglobulin A. It’s one of the most common types of PI. Because adults and children with selective IgA deficiency usually have normal amounts of other immunoglobulins (antibodies), many go undiagnosed because they are never sick enough to raise the alarm.

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There are over 450 different types of PI, each with its own characteristics and challenges.
Need a crash course? Learn the basics of PI.

What does IgA do?

IgA protects areas of the body that come in contact with the environment and have a moist lining (mucosal surfaces). These sites can be found in the mouth, ears, eyes, sinuses, nose, throat, airways within the lungs, gastrointestinal tract, and genitals. IgA antibodies are present in secretions of the mucosal surfaces and play a role in protecting them from infection. Because the area of a person's mucosal surfaces is quite large, equal to 1.5 tennis courts, IgA is an extremely important antibody.

Symptoms of selective IgA deficiency

People with selective IgA deficiency are at a higher risk of infection. The experiences of IgA deficiency can vary greatly. Many adults and children with selective IgA deficiency go undiagnosed because they are never sick enough to see a doctor, while others may develop more severe or recurring problems.

Some selective IgA deficiency symptoms may include:

  • Repeated ear infections
  • Sinus infections
  • Infections of the bronchi (airways of the lungs)
  • Pneumonia
  • Gastrointestinal infections
  • Ongoing diarrhea
  • Allergies and asthma

People with selective IgA deficiency may also be more susceptible to autoimmune diseases. About one-third of selective IgA deficiency patients have an autoimmune disease. These diseases cause the immune system to mistakenly attack the body's healthy tissues and cells. Autoimmune diseases often seen in people with selective IgA deficiency include systemic lupus erythematosus, rheumatoid arthritis, celiac disease, and/or a disorder that causes low platelet counts in the blood.

Diagnosis of selective IgA deficiency

Ongoing or recurrent infections, allergies, sinusitis, respiratory tract infections, chronic diarrhea, or a combination of these issues can lead doctors to suspect selective IgA deficiency in children and adults. The diagnosis is made when a blood test shows very low IgA with normal levels of the other major types of immunoglobulins (IgG and IgM).

What should I know about treatment for selective IgA deficiency?

You are not alone, but no one is quite like you. It's important to learn about the various treatments for PI, and should be individualized to meet your specific needs. Your healthcare team is there to provide recommendations based on you, and your situation. Here are some tips:

  • Keep track of how you're doing and share the information with your doctor on a regular basis.
  • Your doctor will only know how you're doing if you tell them. If you have questions, concerns, thoughts or feelings-speak up and share!
  • You and your doctor both play a part in managing your health. You can take an active role by learning as much as you can and by following your doctor's recommendations.
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You know more about you, and your doctor knows more about medicine, so together you will work to find the best plan for you.
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What’s your plan?

If you or a loved one has been diagnosed with PI, a doctor can help you craft a treatment plan that’s right for you. Explore treatment options here.

Types of Treatment

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Kristi B., 49

Virginia Beach, VA

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