Primary Immunodeficiency Diseases (PIDs)

Primary immunodeficiency diseases (PI) are genetic conditions in which a part of our defense system is not working properly. Children with PI are at risk for an increased frequency or severity of infections. Primary immunodeficiencies are one of a group of conditions that cause immunodeficiency.

Primary immunodeficiency diseases are a direct result of a missing or dysfunctional immune component. Immune components include white blood cells, antibodies and other antimicrobial proteins. Antibody deficiencies are examples of primary immunodeficiency diseases in which children are susceptible to upper and lower respiratory infections. Primary immunodeficiencies may predispose individuals to autoimmune illnesses or cancer.

Although at first thought to be rare, more than 250 primary immunodeficiency conditions have been discovered since the Human Genome Project was completed in 2003. This international research project analyzed the physical and functional order of human genes, which determine heredity.

The main symptoms of primary immunodeficiencies are:

Recurrent, persistent or unusually severe infections with the common bacteria, fungi and viruses that cause infections in people with normal immunity systems
Infection with certain bacteria that are otherwise harmless in normal individuals, including:
- Staphylococcus or staph (as in staph infection), which may cause skin infection, food poisoning or blood poisonin
- Fungus such as candida (yeast), which may cause oral infection, skin rash or blood infection
- Viruses such as herpes simplex that can cause cold sores

Some of the risk factors for immunodeficiencies include:

A family history of primary immunodeficiency
Chemotherapy for cancer
Solid organ and stem cell transplants
Mutations in genes that normally provide the signature for proteins that are important for complex immune functions
Immunosuppressive medicines used to treat autoimmune conditions such as inflammatory bowel disease and rheumatoid arthritis

Children with primary immunodeficiency diseases should receive care from doctors and nurses who are specially trained to work with young patients with these conditions.

Diagnosis of Primary Immunodeficiency Diseases

Clinical immunologists and pediatric infectious disease specialists at Riley at IU Health will review your child’s medical history with you, noting the frequency and severity of infections. They will also provide advanced testing to determine the type of primary immunodeficiency. These tests may include:

Screening immunological laboratory tests. The types of tests depend on your child’s medical history and physical exam results and may include measuring the level of immunoglobulin (antibodies made by white blood cells) in the blood.
Genetic tests. These tests help determine a molecular cause for the condition.
X-ray. This imaging procedure is used to identify lung infections such as pneumonia, one of the most common conditions in children with PI.

Treatments

Treatment of primary immunodeficiencies depends on the type of deficiency and severity of the condition. Treatment may include:

Changes in antibiotic administration. Your child's doctor may extend or shorten the length of time your child receives antibiotic treatment depending on his or her condition.
Infusion of antibodies from a donor. Children who cannot make their own antibodies receive weekly or monthly intravenous or subcutaneously-administered immunoglobulin indefinitely.
Medicines. Your child's doctor may prescribe medicines that help stimulate immune function. Some missing immune components such as interferon or white blood cell growth factors are approved for use for certain conditions. Antimicrobial medicines (antifungal, antibacterial and/or antiviral) may also be prescribed to prevent infections.
Stem cell transplant. The most severe cases of primary immunodeficiency diseases can be treated with a stem cell transplant.

Key Points to Remember

Primary immunodeficiency diseases (PI) are genetic conditions in which part of the defense system in your child’s body does not work properly.
Although at first thought to be rare, more than 250 primary immunodeficiency conditions have been discovered since the Human Genome Project was completed in 2003.
Patients with recurrent or persistent infections, severe infections or infections caused by organisms that usually do not make you ill may have an immunodeficiency disease.
Treatment for PI may include changing antibiotic treatment, infusion of antibodies from a donor or medicines that strengthen the immune system or prevent infection. The most severe cases can be treated with a stem cell transplant.

Support Services & Resources

Visit these websites to learn more about primary immunodeficiency diseases, their causes and treatment.

Riley at IU Health offers a broad range of supportive services to make life better for families who choose us for their children's care.

Learn More About Riley Support Services

American Academy of Allergy, Asthma & Immunology

This resource provides more information about primary immunodeficiency diseases.

Immune Deficiency Foundation (IDF)

You will find a wealth of information about the many primary immunodeficiencies, their causes, diagnosis and treatment as well as support groups and doctors near you.