Several disorders are associated with IgA deficiency or dysfunction. Selective IgA Deficiency is the most common primary immunodeficiency, characterized by low or absent levels of serum IgA while other immunoglobulin levels remain normal. People with this deficiency are more susceptible to infections, particularly of the respiratory and gastrointestinal tracts. Another disorder is IgA Nephropathy, also known as Berger's disease, where IgA deposits in the kidneys lead to inflammation and damage.
