The prevalence of Selective Immunoglobulin M Deficiency (SIgMD) in Iranian volunteer blood donors.

Background: Selective Immunoglobulin M Deficiency (SIgMD) is known as a rare primary immunodeficiency characterized by an isolated deficiency of serum IgM. Other immunoglobulin levels and T-cell immunity are usually normal; although IgE may be elevated. SIgMD can be asymptomatic or with various bacterial and viral infections.