Primary immunodeficiency disease (PIDD) is a group of more than 150 rare hereditary disorders in which the common feature is a defect in a patient's immune system. Children with a PIDD are more prone to infections than are other kids and are at increased risk for certain autoimmune disorders.
The human immune system consists of white blood cells that travel through the bloodstream and lymph nodes to stop invading germs and prevent diseases. In many PIDDs, certain types of white blood cells are missing, leaving the body vulnerable to frequent infections. There are six categories of PIDDs, depending on the part of the immune system affected:
Infections can strike many parts of the body including the respiratory system, brain and spinal cord. Some PIDDs attack certain organs and tissues, while others may curb a child's growth. PIDDs often run in families.
Children with PIDDs are usually more susceptible to infections, have infections that won't go away or have recurrent severe infections. Over time, a child with a PIDD may develop more harmful diseases or disorders. Signs of PIDD in children may include
If your child has recurrent, severe infections or doesn't respond to treatment, see a doctor.
Primary immunodeficiency diseases (PIDDs) are a group of inherited disorders that impair a child's immune system. Unlike secondary, or acquired, immune deficiencies that result from a virus or medications, PIDDs are present at birth. Symptoms usually show up in infancy and can range from mild to severe.
Children with a PIDD often have severe, recurrent infections, sometimes requiring hospitalization. Infections may include sinusitis or bronchitis, ear infections or pneumonia. Some children with PIDD have an autoimmune disorder such as Type 1 diabetes or lupus. If your child has unusually severe infections, or if you have a family history of PIDD, see a doctor.
Your child's doctor will begin a diagnosis of primary immunodeficiency disease by asking you a series of questions such as
The doctor will give your child a physical exam and may perform some tests. Tests for PIDD include
Blood tests: These can reveal whether your child has normal levels of immunoglobulin in the blood. Immunoglobulin is a protein that fights infection. Blood tests can measure levels of other immune system cells as well.
Prenatal testing: If you're pregnant and you already have a child with a PIDD, your doctor may want to test for it before the baby is born. Amniotic fluid, blood and tissue samples can reveal abnormalities so a PIDD can be treated as soon as your child is born.
Most primary immunodeficiency diseases (PIDDs) are diagnosed in infancy or early childhood. Most of the 150 or so different types of PIDDs are rare, affecting around 200,000 people in the United States. Although the risk of serious infections is high in children with a PIDD, most can go to school and lead relatively normal lives.
Treatments include preventing and managing infections, boosting the immune system and addressing the underlying deficiency.
Preventing infections: Keeping a child with PIDD healthy may involve avoiding contact with sick people, frequent hand washing and feeding your child a healthy diet. Vaccinations can help prevent certain kinds of illnesses as well. It is also important not to compromise your child's immune system with pollutants such as cigarette smoke.
Managing infections: Antibiotics are usually used to treat infections caused by bacteria. If the infection doesn't respond to typical medications, your child may need intravenous antibiotics in a hospital. Other medications, such as pain relievers, decongestants or expectorants, can help with various symptoms as well.
Boosting the immune system:
Curing a PIDD: Stem cell transplants can offer children a permanent solution for a PIDD. Stem cell transplantation involves replacing your child's defective immune system cells with normal stem cells from a donor. The donor must be a close biological match to your child for the treatment to succeed—usually a parent or sibling. Please note that stem cell transplants don't always work and your child's immune system may be further compromised during the procedure.
This page has links to brief descriptions of primary immunodeficiency diseases.
National Institute of Allergy and Infect and Infectious Diseases
A good deal of information is offered in this chapter from the handbook, “Infants and Children Living with Primary Immunodeficiency Diseases.”
Immune Deficiency Foundation
This is a general description of primary immunodeficiency diseases, with links to details about specific PIDDs.
American Academy of Allergy Asthma & Immunology
Unlike acquired immune deficiencies that are caused by a virus or immune-suppressing medications, PIDD is a hereditary condition. Primary immunodeficiency diseases are abnormalities in the immune system that hinder the body’s ability to fight disease.
Most PIDDs are extremely rare. About 200,000 people in the U.S. suffer from the most common forms of the disease.
Most of the 150 or so PIDDs involve a white blood cell deficiency. Children are more likely to have a PIDD if a parent or close relative has the condition.
Children with PIDD are susceptible to chronic, hard-to-treat infections. Infections may involve the respiratory and digestive systems, the skin, or other organs.
Your child’s doctor will ask you about your child’s symptoms and the family’s medical history. Blood tests can identify PIDD.
Treatments for PIDDs focus on prevention and on treating infections. In more serious cases, children may need immune-boosting therapies or even a stem cell transplant.
Some children with mild forms of PIDD may be able to function normally. Other children may be at increased risk of autoimmune disorders, such as Type 1 diabetes and certain cancers.