Development of a common variable immunodeficiency in IgA-deficient patients.

IgA deficiency (IgA-D) and common variable immunodeficiency (CVID) are two primary immunodeficiencies that share clinical features. Occasionally, both diseases have been diagnosed in the same family, which suggests the existence of some common pathogenic mechanism, but progression from IgA-D to CVID has rarely been documented. We report three cases of CVID diagnosed 1 to 12 years after IgA-D was detected. Two of these patients presented autoimmune diseases followed by a progressive decline in IgG levels. They are currently on intravenous immunoglobulin therapy with complete remission of their autoimmune and infectious symptoms.