Primary immunodeficiency
DEFINITION
Primary immunodeficiency disorders — also called primary immune disorders or primary immunodeficiency — weaken the immune system, allowing infections and other health problems to occur more easily.
Many people with primary immunodeficiency are born missing some of the body’s immune defenses, which leaves them more susceptible to germs that can cause infections.
Some forms of primary immunodeficiency are so mild they may go unnoticed for years. Other types are severe enough that they’re discovered almost as soon as an affected baby is born.
Treatments can boost the immune system for many types of primary immunodeficiency disorders. Most people with the condition lead relatively normal, productive lives.
CAUSES
Many primary immunodeficiency disorders are inherited — passed down from one or both parents. Problems in the DNA — the genetic code that acts as a blueprint for producing the cells that make up the human body — cause many of the immune system defects in primary immunodeficiency.
There are numerous types of primary immunodeficiency disorders. In fact, research has led to a dramatic increase in the number of recognized primary immunodeficiency disorders in recent years, so they’re not as rare as once thought. They can be broadly classified into six groups based on the part of the immune system that’s affected:
- B cell (antibody) deficiencies
- T cell deficiencies
- Combination B and T cell deficiencies
- Defective phagocytes
- Complement deficiencies
- Unknown (idiopathic)
SYMPTOMS
One of the most common signs of primary immunodeficiency is an increased susceptibility to infections. You may have infections that are more frequent, longer lasting or harder to treat than are the infections of someone with a normal immune system. You may also get infections that a person with a healthy immune system likely wouldn’t get (opportunistic infections).
Signs and symptoms differ depending on the type of primary immunodeficiency disorder, and they vary from person to person.
Signs and symptoms of primary immunodeficiency can include:
- Frequent and recurrent pneumonia, bronchitis, sinus infections, ear infections, meningitis or skin infections
- Inflammation and infection of internal organs
- Blood disorders, such as low platelet counts or anemia
- Digestive problems, such as cramping, loss of appetite, nausea and diarrhea
- Delayed growth and development
- Autoimmune disorders, such as lupus, rheumatoid arthritis or type 1 diabetes
When to see a doctor
If your child or you have frequent, recurrent or severe infections or infections that don’t respond to treatments, talk to your doctor. Early diagnosis and treatment of primary immune deficiencies may prevent infections that can cause long-term problems.
