what causes antibody deficiency
Antibody deficiencies, also called immunoglobulin deficiency syndromes, are immune system disorders that are characterized by low or absent levels of immunoglobulin in the blood.Immunoglobulins (Ig) are antibodies that play an essential role in the body's immune system.he antibodies are present in the bloodstream or bound to the outer surfaces of B-cells or plasma cells. There are five classes of immunoglobulins: IgA, IgD, IgE, IgG, and IgM. Patients who have antibody deficiencies may have reduced or absent levels of one or more types of immunoglobulin.