What is the definition or description of: iga deficiency?

IgA deficiency: Inability to make a class of antibody (IgA) that plays a major role in mucosal immunity (gut and respiratory tract predominantly). May result in recurrent infection, but is often discovered incidentally. May also forecast the development of a more severe immune problem called combined variable immune deficiency (CVID) or be a risk factor for an anaphylactic reaction to blood products with IgA.