Common variable immunodeficiency is a congenital immunodeficiency disorder characterized by very low antibody (immunoglobulin) levels despite a normal number of B cells (lymphocytes).
Common variable immunodeficiency usually develops between the ages of 10 and 20, sometimes earlier and sometimes later. The number of B cells is normal, but the cells do not mature and thus cannot produce immunoglobulins. In some people with this disorder, T cells (lymphocytes) also malfunction.
Recurring lung infections, particularly pneumonia, are common. People may develop a chronic cough, cough up blood, or have difficulty breathing. Autoimmune disorders, including Addison's disease, thyroiditis, and rheumatoid arthritis, often develop. Diarrhea may occur, and food may not be absorbed well from the digestive tract. The spleen may enlarge. Stomach cancer and lymphoma develop in 10% of people.
Doctors suspect the disorder if typical symptoms occur in people who have several family members with autoimmune disorders. Blood tests are done to measure immunoglobulin levels.
Infusions of immune globulin (to provide the missing immunoglobulins) are given throughout life, and antibiotics are promptly given to treat infections. Autoimmune disorders are treated as needed with rituximab (a monoclonal antibody also used to treat lymphomas and rheumatoid arthritis) or a corticosteroid. Life span may be shortened.
Last full review/revision September 2008 by Rebecca H. Buckley, MD