Selective IgA deficiency is the most common primary immunodeficiency disease (PIDD), and is more prevalent in caucasians. People with this disorder have absent or very low levels of immunoglobulin (antibody) A (IgA) in their blood and secretions. IgA protects against infections of the mucous membranes lining the mouth, airways and digestive tract.
Although individuals with selective IgA deficiency do not produce adequate amounts of IgA, they do produce all the other immunoglobulin classes in appropriate amounts. This is why many people with selective IgA deficiency appear healthy or only have mild recurring illness such as gastrointestinal infections.
A common problem in selective IgA deficiency is susceptibility to infections. A second major problem in selective IgA deficiency is increased occurrence of autoimmune diseases. Also, many people with selective IgA deficiency also have allergies and/or asthma.
Selective IgA Deficiency Symptoms & Diagnosis
The most common symptom of selective IgA deficiency is susceptibility to infections including:
- Ear infections
- Chronic diarrhea caused by gastrointestinal infections
Selective IgA deficiency may also cause autoimmune disease, in which the immune system attacks the host. Common examples of these diseases are rheumatoid arthritis and lupus. Those with selective IgA deficiency also have a small increased risk of life-threatening allergic reactions (anaphylaxis) when they receive blood products.
Diagnosis requires blood screening to show an IgA deficiency but normal levels of other immunoglobulins.
Selective IgA Deficiency Treatment & Management
The underlying cause for selective IgA deficiency is unknown and there is currently no way to replace IgA in the body.
Unlike many other immunoglobulin deficiencies, the condition is not treated with immunoglobulin replacement therapy.
In cases where recurrent infections are a problem, preventative antibiotics may be used to help diminish the frequency of infections. Individuals with selective IgA deficiency often require a longer course of antibiotics for infections to clear up.