Selective IgA deficiency is an immune system condition in which an individual doesn’t have enough immunoglobulin A in their system. Immunoglobulin A (IgA) is a protein that helps rid of infection in the body (the sites include the mouth, ears, sinuses, nose, throat, airways within the lungs, gastrointestinal tract, eyes, and genitals)
There are several classes of immunoglobulins and each class helps protects the body from infection in a different way. The most commonly affected class is class A (immunoglobulin A).
Most individuals with selective IgA deficiency don't have recurrent infections; however, some may experience recurrent respiratory tract infections, asthma, sinus infections, allergies and diarrhea.
Selective IgA deficiency is also linked with autoimmune disease, in which the immune system attacks its own organs and tissues in the body. Common autoimmune conditions found with IgA deficiency include rheumatoid arthritis, lupus and celiac disease.
Many individuals with selective IgA deficiency have no symptoms; however, they are at greater risk of contracting infections. If an individual does experience symptoms, they can include:
- Chronic diarrhea
- Eye infection
- Mouth infection
- Ear infection
- Skin infection
- Upper respiratory tract infections
- Gastrointestinal inflammation
- Unexplained asthma
The cause of IgA deficiency is usually genetics (inheritance of the condition). It may be inherited as an autosomal dominant or autosomal recessive trait. A few research evaluations have shown that environmental factors such as drugs or infections can cause IgA deficiency, however, these forms are reversible in more than half the cases.
Possible complications that can arise from Selective IgA deficiency are autoimmune disorders such as:
- Rheumatoid arthritis: A severe inflammatory condition that affects the joints in the hands and feet.
- Systemic lupus erythematosus: An inflammatory disease caused when the immune system attacks its own tissues.
- Celiac sprue: An immune reaction to eating gluten, a protein found in wheat, barley, and rye.
- Anaphylactic reactions: Allergic reactions to a blood transfusion or to immune globulin
No specific treatment is available for Selective IgA deficiency. Most individuals who have bacterial infections of the ears, sinuses, lungs or gastrointestinal tract are given antibiotics to treat the infections and prevent their reoccurrence. Selective IgA deficiency that results from taking a drug usually resolves if the drug is stopped.
There is a method of treatment in which individuals with selective IgA deficiency who also have IgG subclass deficiencies may be helped with intravenous immunoglobulin (IVIG), given through a vein. Subcutaneous immunoglobulin (SCIG) treatments given under the skin may also help. However, there is no evidence that proves that intravenous immunoglobulin and subcutaneous immunoglobulin fully treat this condition, but rather help relieve an individual’s symptoms.
Individuals with selective IgA deficiency are advised to wear a medical identification bracelet to prevent inadvertent plasma or IVIG administration, which could lead to anaphylaxis. Anaphylaxis is a severe, potentially life-threatening allergic reaction.
While there is no known prevention for IgA deficiency, genetic counseling has been proven helpful for prospective parents with a family history of selective IgA deficiency,