Primary Immunodeficiency

Primary immunodeficiency diseases (PIDD) are conditions that affect your immune system. If you have a PIDD, parts of your immune system don’t work as they should.

If you have a primary immunodeficiency, you’ll get sick more often than most people. That’s because your immune system doesn’t have all the tools it needs to fight off germs and other invaders that may cause infections. You may live with a compromised immune system. This will increase your risk of complications, even from common infections that are usually minor.

Types of primary immunodeficiency

There are more than 400 types of primary immunodeficiencies. Some cause symptoms as soon as you’re born. Others may not affect you until you’re an adult.

They range from mild to severe. Mild types may only cause minor symptoms. Severe PIDD can cause fatal complications.

Some primary immunodeficiency diseases include:

• Common variable immunodeficiency (CVID)
• Ataxia-telangiectasia
• Chronic granulomatous disease (CGD)
• DiGeorge syndrome
• Hemophagocytic lymphohistiocytosis
• Selective IgA deficiency
• X-linked agammaglobulinemia
• Severe combined immunodeficiency (SCID)
• Wiskott-Aldrich syndrome

What is secondary immunodeficiency?

Secondary immunodeficiency is when a health condition or a medication factor causes immunodeficiency. It’s a different issue, but it can cause similar symptoms.

Lots of conditions can cause it, including:

• Diabetes and other autoimmune diseases
• HIV and AIDS
• Some cancers
• Cirrhosis
• Undernutrition

Medications that can weaken your immune system include:

• Immunosuppressants
• Corticosteroids
• Chemotherapy
• Radiation therapy

Symptoms of primary immunodeficiency

Getting sick more often than usual is the most common symptom. You might catch infections more easily than people around you. And when you do get sick, you may experience more severe symptoms or complications.

You might notice that it takes you longer to recover from an illness than others. Infections may go away and come back, even after you start a treatment.

Other symptoms can include:

• Needing antibiotics longer than usual
• Enlarged spleen
• Swollen lymph nodes
• Unexplained weight loss or poor growth
• Having diarrhea or other digestive issues often
• Experiencing more side effects after getting a live vaccine

Most people with a PIDD experience symptoms before turning 20. But they can develop at any point in life.

Primary immunodeficiency causes

Genetic changes cause primary immunodeficiencies. They prevent your immune system from developing and working correctly. It might be:

• Less active than it should be
• Missing cells that it usually has
• Completely missing

You can’t control the genetic changes — they happen before you’re born. Which genes are changed will determine the disorder you develop.

Risk factors for these diseases

The changes that cause primary immunodeficiencies often run in biological families. That means if your biological parents or siblings have a PIDD, you may be more likely to have one, too.

These disorders are more common in males.

How doctors diagnose these disorders

A healthcare provider will diagnose a PIDD based on a few factors:

• Your medical history (tell your provider if you know you’ve had any infections recently)
• A physical exam
• The symptoms you’re experiencing
• Your family history (tell them if you know someone in your family has a PIDD)

Your provider will probably use a few tests, including:

• Blood tests to look for signs of infections
• Genetic testing to check for changed genes
• Flow cytometry to examine a sample of your immune cells

Every state in the U.S. tests babies for severe combined immunodeficiency (SCID) when they’re born. That’s because SCID is fatal if it’s not treated right away.

How are these disorders treated?

Your healthcare provider will suggest ways to manage and prevent infections. The treatment you’ll need depends on which PIDD you have.

You might need:

• Antibiotics to prevent or treat bacterial infections
• Antivirals for viral infections
• IVIG infusions to boost your immune system’s natural defenses
• A stem cell transplant if you have a risk of life-threatening complications
• Gene therapy that may repair or replace changed genes

When should I see my healthcare provider?

Visit a healthcare provider if you feel like you get sick too often. Everyone gets sick every once in a while. But you know your body better than anyone. You can tell when something doesn’t feel right.

Talk to your provider if you’ve started treatment for a PIDD and it feels like your medications aren’t working. Tell them if you have a fever or infection. They’ll suggest ways to avoid complications.

What can I expect if I have a PIDD?

You’ll have to monitor your body for signs and symptoms of infections. And you may need to take medications for the rest of your life. Your healthcare provider will help you understand the best ways to avoid infections, including:

• Washing your hands often (especially after going to the bathroom and before eating)
• Staying up-to-date on the vaccinations your provider suggests
• Getting enough sleep
• Following a healthy eating plan
• Getting enough physical activity

Your loved ones can help you stay safe and healthy, too. Ask them to let you know if they’re sick, feel unwell or have had an infection recently. This can help them avoid accidentally spreading infections when they see you in person.