Predominantly Antibody Deficiencies

**Semantic type:** Disease or Syndrome

**Definition:** A group of primary immunodeficiency diseases caused predominantly by antibody deficiencies, comprised of: Agammaglobulinemia with absent B cells; Severe reduction in at least two serum immunoglobulins, common variable immunodeficiency (CVID) phenotype; Severe reduction in serum IgG and IgA with normal or elevated IgM, hyper-IgM; and Isotype, light chain, or functional deficiencies with generally normal numbers of B cells.