Primary Immunodeficiency: Types, Symptoms, and Treatment

Written by Michele Cohen Marill, Bethany Afshar
Medically Reviewed by Jabeen Begum, MD on March 20, 2025
13 min read

If your child has a primary immunodeficiency disease (PIDD), their immune system doesn’t work the way it should. That means their body has a harder time fighting off germs that can make them sick. A common cold that’s no big deal for others could turn into a severe infection that takes a long time to go away or needs treatment from a doctor. 

When you first learn that your child has a PIDD, you might worry that infections are going to rage out of control. But lots of treatments can keep symptoms in check and help your child stay healthy and active.

“Primary immune deficiency has made a lot of advancements in the last 30 years,” says Inderpal Randhawa, MD, board-certified internist, immunologist, pediatrician, pediatric pulmonologist, and medical director of the Children’s Pulmonary Institute at MemorialCare Miller Children’s & Women’s Hospital Long Beach in Long Beach, CA.

If your child has one of the more common forms of PIDD, “there are really wonderful opportunities for care that can allow them to lead a normal life,” says Randhawa. “It’s not simple. It requires testing and specialty care. It might involve taking certain medications or certain infusions. But most of the folks who get diagnosed can be managed on an outpatient basis. The side effects to treatment are very few and manageable. And long-term, [people with some types of PIDD] appear to do very well.”

Here’s what else you need to know about this group of immunodeficiency diseases.

Many cases of PIDD are first found in babies or young children, but sometimes symptoms don’t show up until adulthood. 

Immunodeficiency disorders can be tricky to diagnose since there are many different types. All kinds make your child more likely to get sick from infections. Milder immunodeficiency disorders are often well-managed with medication, while severe cases require more intense care. In some cases, a bone marrow (stem cell) transplant may be needed.

There are over 550 different kinds of immunodeficiency disorders. The list includes:

Selective Immunoglobulin A (IgA) deficiency

IgA is an antibody your body makes to fight off illness. It’s found in your mucus membranes, spit, tears, and breastmilk. If your child’s immune system doesn’t make enough IgA, they may be more likely to have asthma, allergies, or autoimmune conditions. But some people with selective IgA deficiency don’t have any symptoms at all.

Common variable immunodeficiency (CVID)

If your child has this PIDD, their immune system doesn’t react with enough force when it needs to fight off germs. And some of the antibodies their body does make attacks their own cells by mistake.

About 1 in 25,000 people are diagnosed with CVID. The most common signs are repeated infections in the ears, sinuses, lungs, and bronchi (the tubes that carry air into the lungs). 

X-linked agammaglobulinemia (XLA)

Some babies are born without certain cells (B cells) that make antibodies. That leaves a gap in a crucial part of their body’s defense system. XLA is sometimes called Bruton’s agammaglobulinemia after the doctor who discovered it. It can also be called congenital agammaglobulinemia.

XLA raises the risk for infections on or near the mucus membranes — for instance, inside the ears, gastrointestinal (GI) tract, sinuses, or lungs. They can then spread through the bloodstream to other parts of your child’s body.

Severe combined immunodeficiency (SCID)

This is one of the most severe immunodeficiency diseases. A child with SCID is missing not only B cells, which make immune cells, but also T cells, which directly attack germs. Because this leaves them without much of a defense system, SCID can be life-threatening. Early diagnosis and treatment are crucial.

DiGeorge or 22q11.2 deletion syndrome (DGS)

If your child has DGS, they have 90% fewer T cells than other kids their age. About 10% of people with DGS can’t make T cells at all. DGS symptoms can range from mild to severe and include infections that keep coming back and heart defects that need surgery.

Chronic granulomatous disease (CGD)

Your body makes chemicals to kill some germs that try to make you sick. If your child has CGD, they’re missing the special cells (phagocytes) that can do this. Other immune cells step in and try to help out, which can form granulomas, or large clusters of cells. These can cause other issues, especially when the granulomas in your child’s bowels or urinary tract.

Hyper-IgE syndrome (HIES) or Job’s syndrome

HIES is caused by a damaged gene that makes your child’s immune system both underreact and overreact. They have too many white blood “fighter” cells and too few antibodies trying to fight off germs. There are two types of HIES, based on where the mutated gene is found.

Skin issues such as eczema and lung infections like pneumonia are common symptoms of this immunodeficiency disorder. HIES can also lead to other health issues, such as bone fractures, skin cancer, and lymphoma (cancer in infection-fighting cells).

To learn about other types of immunodeficiency disorders, check with a trusted expert source, such as the Immune Deficiency Foundation (IDF). 

You can’t catch PIDD like you can a cold or the flu. Your child has it because they were born with a broken gene that affects their immune system.

Sometimes, this issue runs in families. Or it may have happened on its own.

As a result, their immune system doesn’t work well. In some cases, it may be totally absent. This makes your child more likely to get sick from infections that wouldn’t take hold in someone else.

What are the risk factors for primary immunodeficiencies?

If someone else in your family has a PIDD, your child is more likely to have one, too. So far, family history is the only known risk factor.

How PIDD affects your child will depend on the type they have. Some general symptoms include:

  • Delayed growth 
  • Weight loss or trouble gaining weight
  • Frequent infections, such as ear and skin infections, sinusitis, bronchitis, or pneumonia
  • Infections that need antibiotics through an IV to clear up 
  • Chronic diarrhea or other ongoing digestive issues
  • A severe, fast-moving illness, such as septicemia, a bacterial infection of the blood
  • An autoimmune disorder, such as type 1 diabetes or rheumatoid arthritis
  • Swollen lymph nodes
  • Enlarged spleen
  • A reaction to a live vaccine (such as the flu shot)
  • An infection needing more than one course of antibiotics for treatment

All states now screen newborns for SCID — the most severe type of PIDD. But if your child has repeated infections or you have a sense that something isn’t right with their health, talk to their doctor.

After doing a physical exam, they may ask you questions such as:

  • Has your child had a lot of severe infections?
  • If so, how long do they last?
  • Does your child stay sick even after taking antibiotics?
  • Do other people in your family tend to get sick a lot?
  • Do immune system disorders run in your family?

Your doctor may order tests to get more information about your child’s health. This could include:

Blood test. A small sample of your child’s blood will be sent to a lab. The results can give clues about how their immune system is working.

Genetic test. This type of test can actually look for missing or mutated genes. It may take a while to get the results.

Flow cytometry test (FCM). This is a newer diagnostic tool, which uses a laser to look closely at your child’s immune cells. It can help your doctor make a diagnosis more quickly than a genetic test.

Make sure to find a clinical immunologist to care for your child, advises Randhawa. “Most allergists don’t practice immunology. They do allergy-based work. Then amongst that group is a very small group of people who really are focused on immune-based deficiencies and disorders.”

PIDD nonprofits often have lists of these specialized doctors.

You may have a lot of questions when your child is first diagnosed with PIDD. It can be helpful to write them down and bring them to your next doctor visit. Some things you might ask include: 

  • How can I keep my child from getting sick?
  • What’s the best treatment for them and why?
  • Will they have side effects from the treatment?
  • Should my child get all the usual vaccines?
  • Does my child need to stay away from some sports?
  • What are the signs that my child has a severe infection?
  • What steps do I take if I see them?

Your child’s treatment will have a few different goals. You’ll want to try to prevent new infections from happening. And you’ll need to carefully manage symptoms when they do get sick. That way, your child can feel better faster and get back to doing their favorite things.

For instance, they may need to get higher doses of infection-fighting medications and take them for a longer time. If an infection is serious, your child might need antibiotics put into their veins through an IV.

Even if they’re not sick now, your doctor may give them antibiotics or other medicines to prevent an illness.

Your doctor could also suggest treatments to improve your child’s immune system. These include:

Immunoglobulin (Ig) replacement therapy

Doctors can give your child more disease-fighting antibodies through a needle, by IV. This can reduce the risk of illness or lessen the severity of an infection.

Some people only have Ig therapy once, but it’s more common to get it on a weekly or monthly basis.

Ig therapy is safe and works well. But your child might have some mild side effects, such as a headache, nausea, and achy muscles.

Stem cell transplant

In severe cases, your child could get healthy immune cells from someone else. 

You’ll need to find a donor who can supply stem cells, which are very young cells that can become working immune cells.

The donor will need to be the right match for your child so that their body accepts the new cells. Close family members, such as a brother or sister, are the best chance. Someone from the same racial or ethnic background may also be a good donor. If no one you know is a match, you can put your child on a waiting list.

During the transplant, your child will get the new stem cells through an IV. 

It could take three to five weeks for these cells to multiply and start making healthy, working blood cells. During this time, your child may need to stay in the hospital. It can take a year before the number of good blood cells in their body gets up to normal.

A stem cell transplant can be a cure for some types of PIDD.

Gene therapy

This treatment can help with a few types of immunodeficiency diseases. Doctors take some of your stem cells, fix the damaged gene, then put the “fixed” stem cells back into your body through an IV.

Researchers are trying to learn through clinical trials what other types of PIDD can be helped with gene therapy. Your doctor can help you understand if your child might be a good candidate.

Having an immunodeficiency disorder can put your child at risk for:

  • Autoimmune disorders
  • Blood disorders
  • Some types of cancer

Getting a PIDD diagnosis and starting treatment as soon as possible can help your child avoid these more serious issues.

Even with a PIDD, your child will be able to make friends, do activities they love, and explore the world. Here’s how you can support them.

Speak up for them. For instance, if your child goes to school, meet with their teachers to explain their condition. Let them know your child may need to miss classes more often than other kids. Tell the school nurse about medications they’ll need to take and when to contact you.

Make healthy foods a priority. Prepare meals with nutrient-rich foods, such as fruits, vegetables, whole grains, and lean protein. 

Stay active. Help your child find a sport or physical activity they enjoy and is safe for them to do. Even playing tag with their friends or running with the family dog could be good for their physical and mental health.

Sleep well. Everyone needs sleep to be at their best. Set a bedtime for your child and stick to it. 

Keep germs away. Remind your child to wash hands often, especially before and after eating and after using the bathroom. An alcohol-based hand sanitizer will work when soap and water aren’t around.

Keep stress in check. Stress can make it harder for your child’s already weakened immune system to fight off germs. Encourage them to relax, play, and enjoy hobbies. If you or your child need more tips for managing their condition, talk to a mental health expert. 

When your child has an immunodeficiency disorder, your whole family can benefit from support. Sometimes that comes from friends, family, coworkers, and neighbors. But it can also help to connect with other families who know what you and your child are going through.

A PIDD community can be a great place to share both stories and resources. You can check out online options through immunodeficiency groups, or ask your child’s doctor if they can suggest an in-person group. 

Working with a primary immunodeficiency

If you’re an adult with a compromised immune system, you may worry about juggling your career with your health needs. It may help to:

Focus on your skills and strengths. Try not to let your diagnosis define you. 

Know your rights. PIDD qualifies as a medical disability under the Americans with Disabilities Act (ADA). That means you may qualify for some special accommodations, such as working from home when you don’t feel well or taking time off for a doctor’s visit.

Decide how much you’ll share. Unless it prevents you from doing your job or you’re asking for accommodation, you don’t have to tell your boss that you have a PIDD. 

To learn more about working with PIDD, contact a patient advocate group.

Safe travel for those with a primary immunodeficiency 

When you’re traveling, especially outside the U.S., make sure to:

Make a list of contacts ahead of time. For instance, is there a chapter of a PIDD group where you’re going? What about a PIDD specialist? Where is the nearest hospital?

Check with your health insurer. Are you covered when you travel? If not, you might want to look into separate short-term insurance.

Get a letter from your doctor. It should include your condition and why you need to carry certain medications with you. Keep it with you at all times.

Know how to opt out of vaccines. Some countries want visitors to have special vaccines before they arrive. If you can’t have them because of your weakened immune system, find out before your trip how to get an exemption. 

Managing your child’s immune system health problems may feel overwhelming at times, but you don’t have to do it alone. Reach out to family and friends. Talk to your doctor about how to meet other families who are living with PIDDs. They’ll understand what you’re going through. 

PIDD groups can be helpful at various stages of your journey. For instance, they can help you find a doctor, get in touch with a support group, and find a clinical trial. 

Clinical trials test new treatments to confirm that they’re safe and see how well they work. They can be a way to try medicines that aren’t yet available to everyone. Your doctor can tell you if a clinical trial could be a good option for your child.

If your child has a PIDD, their immune system doesn’t work as well as it should. This makes them much more likely to get infections. An early diagnosis is often key to preventing more serious health issues. With the right treatment, many children with PIDD are likely to have a full and active life. Making healthy decisions every day, such as washing hands often, eating healthy foods, and getting enough sleep, will also help support your child’s immune system.

What is the difference between primary and secondary immune deficiency?

A primary immune deficiency is caused by a mutated gene. A secondary immune deficiency is due to another health condition or a certain medication that weakens the immune system. 

Is there a diet routine to prevent primary immunodeficiency? 

PIDD happens because of a broken or missing gene. There’s nothing that you or your child could have done differently to prevent it. That said, eating plenty of healthy foods, such as fruits and vegetables, can help support your child’s immune system. That may lower their risk of getting infections.

What are IgA and IgG?

Immunoglobulins are antibodies. Different types have different tasks. Immunoglobulin A (IgA) antibodies defend your GI and respiratory tracts from germs. They’re found in your blood, stomach juices, and spit. Immunoglobulin G (IgG) antibodies are the most common antibodies in your blood. They help defend you from infections. Your immune system keeps track of every type of germ it comes across. That way, it can quickly make more IgG if that certain germ tries to invade again.