Prevalence of Immunocompromised Kids

Despite the probability of getting frequent upper respiratory infections and a few gastrointestinal infections each year, most kids have strong immune systems.

Some don’t though.

And these immunosuppressed kids are at increased risk for infections, including vaccine-preventable diseases.

Children With Primary Immunosuppression

There are at least 250 different conditions that can cause immune system problems.

These primary immunodeficiencies, which are caused by a genetic condition and the primary problem is with the immune system itself, can include:

• Antibody Deficiencies: X-linked agammaglobulinemia, common variable immunodeficiency, selective IgA deficiency, and IgG subclass deficiency, etc.
• Cellular deficiencies - severe combined immunodeficiency (SCID) disease, DiGeorge syndrome, Wiskott-Aldrich syndrome, and ataxia-telangiectasia, etc.a
• Innate Immune Disorders: chronic granulomatous disease, hyper IgE syndrome, leukocyte adhesion defects, and myeloperoxidase deficiency, etc.

How Common Are These Conditions?

They are probably more common than most people think, which is why it is important to look for the warning signs of a primary immunodeficiency if your child seems to be getting sick a lot, including:

• Having severe infections that require hospitalization or intravenous antibiotics, instead of more standard oral antibiotics
• Having infections in unusual locations or that are caused by an unusual or uncommon virus, bacteria, or fungus, etc.
• Having persistent infections that never seem to completely go away
• Having infections that keep coming back
• Having other family members with similar problems with severe infections

A 2007 survey in the United States estimated “prevalence rates for diagnosed PID as 1 in 2,000 for children, 1 in 1,200 for all persons, and 1 in 600 households.” Other surveys suggest that the prevalence rates might be even higher.

Secondary Immunosuppression

In addition to primary immunodeficiencies, kids can have secondary immunodeficiencies, in which another condition affects a child’s immune system.

These secondary immunodeficiencies can include:

• Infections like HIV
• Medication side effects from chemotherapy for treating kids with cancer to methotrexate for arthritis and prednisone for nephrotic syndrome, many children are at risk for infections because the medications they take make it harder for their body to fight infections
• Chronic conditions, including diabetes mellitus, who are at greater risk of the flu, and kidney failure/dialysis
• Children with asplenia (no spleen) or functional asplenia (a spleen that doesn’t work well) - whether it is caused by sickle cell disease, hereditary spherocytosis, or they had their spleen removed after trauma, these kids are at risk for life-threatening bacterial infections, especially Hib, Neiserria meningitis, Streptococcus pneumonia, etc.
• Severe malnutrition

How many kids are there with these types of secondary immunodeficiencies?

While there don’t seem to be any complete statistics on the prevalence of secondary immunodeficiencies, they would include:

• About 10,000 children and teens living with HIV
• Just over 15,700 children and teens who are diagnosed with cancer each year, many of whom are treated with chemotherapy
• Almost 200,000 children and teens with diabetes mellitus
• About 1,000 children who are born in the United States each year with sickle cell disease

Also, children with many other conditions are at increased risk of infections, including those with lupus, cystic fibrosis, and Down syndrome, etc.

What Parents Should Know About Immunosuppression

There is a lot of misinformation out there about kids with immunodeficiencies, especially as it relates to vaccines. For example, just because kids who are getting chemotherapy can theoretically get inactivated vaccines, it doesn’t mean that they should, as they likely wouldn’t work. You need an active, functioning immune system for a vaccine to work properly. The reason that live vaccines are contraindicated when a child is getting chemotherapy is that it might actually cause the child to get an infection.

Other things to know about kids with immunodeficiencies include that:

• Many kids with a primary immunodeficiency can receive many or all vaccines, including live vaccines, depending on the type of immunodeficiency they have. Others can’t, or the vaccines they receive may not work well, so it is important “to create a 'protective cocoon' of immunized persons surrounding patients with primary immunodeficiency diseases so that they have less chance of being exposed to a potentially serious infection like influenza."
• Many kids with a secondary immunodeficiency may have received many or all of their vaccines before they became immunosuppressed, but they may have lost that protection now because of their immunodeficiency.
• Laboratory tests can help determine if a child has a problem with his immune system.
• Vaccine shedding isn’t usually a problem for most children with immune system problems and it is recommended that close contacts of children with immunodeficiencies receive all vaccines except the oral polio vaccine. And unless they will be in contact with someone who is severely immunosuppressed, such as getting a stem cell transplant and being in a protective environment, they can even get the live, nasal spray flu vaccine.

Although most people have learned about immunodeficiencies from movies and television shows, these kids don’t live in bubbles. They go to school and daycare and try to live normal lives.

We shouldn’t forget that it is not rare for kids to be living with immunodeficiencies.