what is iga deficiency

Selective IgA deficiency (SIgAD) is a primary immunodeficiency characterized by an undetectable or very low level of immunoglobulin A (IgA) in the blood and secretions, while levels of other immunoglobulins like IgG and IgM remain normal. IgA is an antibody that plays a crucial role in immune defense by protecting the mucous membranes lining the mouth, airways, and digestive tract, as well as being present in saliva, tears, and breast milk. Most people with IgA deficiency do not have symptoms, but some may experience recurrent infections, especially in the sinuses, lungs, and gastrointestinal tract, along with an increased risk of allergies, autoimmune diseases, and occasionally severe reactions to blood transfusions containing IgA. The condition is often inherited, and it is the most common primary antibody deficiency worldwide. Treatment typically focuses on managing infections and associated conditions rather than replacing IgA itself. In summary, IgA deficiency is a genetic immune disorder resulting in low or absent IgA antibodies, leading to a higher susceptibility to infections and some autoimmune problems, but many affected individuals remain healthy without symptoms.