Les déficits immunitaires communs variables : définition, physiopathologie et diagnostic biologique

Abstract

AbstractCommon variable immunodeficiency (CVID) is a primary immunodeficiency characterized by a defect in the production of immunoglobulins, it is the most frequent of the primary immunodeficiencies. It mainly affects humoral immunity and results, among other biological signs, in severe hypogammaglobulinemia with a decrease in IgG associated with a decrease in IgA and more rarely IgM. Clinical manifestations are recurrent respiratory and digestive infections, frequently associated with autoimmune diseases and lymphoproliferative syndromes. In most cases, this hypogammaglobulinemia is linked to a decrease in switched memory B lymphocytes, and abnormalities of other element in the immune response (T lymphocytes, cytokines, dendritic cells, etc.). Genetic abnormalities affecting genes coding for many proteins involved in the immune response are described in about 35 % of patients. The diagnosis is a diagnosis of exclusion, by ruling out all other causes of secondary hypogammaglobulinemia. The treatment is injection of polyvalent immunoglobulins, and prophylactic treatment such as antibiotics and vaccinations.