common variable immunodeficiency


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Common Variable Immunodeficiency

 

Definition

Common variable immunodeficiency is an immunodeficiency disorder characterized by a low level of antibodies. Patients with this disease are subject to recurring infections.

Description

Immunodeficiency means that the immune system is deficient in one or more of its components and is unable to respond effectively. Common variable immunodeficiency is the most common of the immunodeficiency disorders. Patients with this disease have frequent infections, especially those caused by the same microorganism. Recurring infections are an indication that the immune system is not responding normally and developing immunity to reinfection. Patients with common variable immunodeficiency have a normal number of B cells, the lymphocytes that make antibodies. In approximately one-third of these patients, the number of B cells in the blood that have IgG antibodies on their surface is lower than normal, but there are normal numbers of B cells in their bone marrow. B cells with IgG antibodies on their surface are capable of responding to microorganisms. The lack of IgG on the surface of the B cells means that they are not prepared to fight infection. The T-cell lymphocytes, those cells responsible for cellular immunity, are usually normal, although some cell signal components may be lacking.

Causes and symptoms

The cause of common variable immunodeficiency is not known, although some forms seem to be hereditary. The main symptom is recurring infections that tend to be chronic rather than acute. Patients may also develop diarrhea and, as a consequence of the diarrhea, do not absorb food efficiently. This can lead to malnourishment that can aggravate the disorder. Common variable immunodeficiency normally appears in children after the age of 10. Autoimmune disorders such as rheumatoid arthritis, thyroiditis, and systemic lupus erythematosus and certain cancers such as lymphomas and leukemias may be associated with common variable immunodeficiency.

Diagnosis

As is true of most immunodeficiency disorders, one of the first signs that the patient has the condition is recurrent infections. Patients with common variable immunodeficiency are subject to recurrent infections, especially those caused by microbes that don't normally cause disease in normal persons. The main diagnostic test that distinguishes common variable immunodeficiency from other immunodeficiency diseases is the low antibody level despite the normal number of B cells. Antibody levels are tested in the serum by a procedure called electrophoresis. This procedure both quantifies the amount of antibody present and identifies the various classes of antibodies. The main class of antibody for fighting infectious diseases is IgG.

Treatment

There is no treatment that will cure the disorder. Treatment for common variable immunodeficiency aims at boosting the body's immune response and preventing or controlling infections. Immune serum, obtained from donated blood, is given as a source of antibodies to boost the immune response. Immune serum is obtained from donated blood. It contains whatever antibodies the donors had in their blood. Consequently, it may not contain all the antibodies that the patient needs and may lack antibodies specific for some of the recurring infections that these patients suffer. Antibiotics are used routinely at the first sign of an infection to help the patient eliminate infectious microorganisms.

Prognosis

With good medical care, people with common variable immunodeficiency usually have a normal life span.

Prevention

The disease itself cannot be prevented, but patients and their families can take precautions to prevent the recurrent infections commonly associated with it. For example, good hygiene and nutrition are important, as is avoiding crowds or other people who have active infections.

Resources

Books

Abbas, Abul K., Andrew H. Lichtman, and Jordan S. Pober. Cellular and Molecular Immunology. 3rd ed. Philadelphia: W. B. Saunders Co., 1997.

immunodeficiency

 [im″u-no-de-fish´en-se]
a deficiency of immune response or a disorder characterized by deficient immune response; classified as antibody (B cell), cellular (T cell), or combined deficiency disorders. Antibody immunodeficiencies are marked by hypo- or dysgammaglobulinemia, recurrent bacterial otitis media, and sinopulmonary infections. Cellular immunodeficiencies are characterized by recurrent low-grade or opportunistic infections, by graft-versus-host disease or reaction after blood transfusions, and by severe disease after immunization with live vaccines. See also acquired immunodeficiency syndrome.
common variable immunodeficiency (CVID) a heterogeneous group of disorders characterized by hypogammaglobulinemia, decreased antibody production in response to antigenic challenge, and recurrent pyogenic infections, often associated with hematologic and autoimmune disorders. Most patients have normal numbers of circulating B cells but lack plasma cells and appear to have an intrinsic defect of B cell differentiation. However, two other forms are also recognized: that due to a disorder of T lymphocyte regulation and that due to production of autoantibodies against T and B lymphocytes.
severe combined immunodeficiency (SCID) any of several rare congenital diseases, some of autosomal recessive and some of X-linked inheritance, in which both humoral and cell-mediated immunity fail to develop normally and T lymphocytes are absent or nearly so. In some forms, B lymphocytes are also absent. Early diagnosis is essential to prevent opportunistic infections. Persistent diarrhea, chronic mucocutaneous candidiasis, and failure to thrive may occur in infancy. Blood transfusions can result in graft-versus-host disease and routine vaccinations in fatal infection. Unless immune function is restored by a matched-donor bone marrow or fetal tissue transplantation or the patient is kept in complete isolation, the prognosis is poor.

com·mon var·i·a·ble im·mu·no·de·fi·cien·cy (CVI),

[MIM*240500]
immunodeficiency of unknown cause, and usually unclassifiable; usual onset after age 15 years but may occur at any age in either sex; the total quantity of immunoglobulin is commonly less than 300 mg/dL; the number of B lymphocytes is often within normal limits but there is a lack of plasma cells in lymphoid tissue; cellular (T-lymphocyte) immunity is usually intact; there is an increased susceptibility to pyogenic sinopulmonary infection and often autoimmune disease.

common variable immunodeficiency (CVID)

a heterogeneous group of disorders characterized by hypogammaglobulinemia, decreased antibody production in response to antigenic challenge, and recurrent pyogenic infections, and often associated with hematologic and autoimmune disorders. Most patients have normal numbers of circulating B cells that can identify antigens and proliferate, but they lack plasma cells and may have an intrinsic defect of B cell differentiation. Two less common forms are also recognized, one caused by a disorder of T lymphocyte regulation and one caused by production of autoantibodies against T and B lymphocytes.

common variable immunodeficiency

A heterogeneous, often AR group of primary immune dysfunctions, which affects 20-90/106 live births, characterized by a ↓ in most immunoglobulin isotypes–B-cell precursors are present, but don't differentiate into plasma cells and T cell defects without major defects in cell-mediated immunity; CVID is usually limited to intrinsic B-cell defects, but in most Pts, there are also defects of T-cell activation and ↓ secretion of IFN-γ, IL-2, IL-4, IL-5, and B-cell differentiation factor Clinical Average age at diagnosis is 12 yrs, by which time many Pts have suffered recurrent bacterial infections, chronic otitis, sinusitis, bronchiectasis, pneumonitis, diarrhea, malabsorption, sprue-like enteritis, achlorhydria, pernicious anemia, cholestasis, and giardiasis, which affect up to 50% of Pts Lab ↓↓↓ Igs, ↓ serum IgG, IgA, and usually IgM, impaired antibody response to antigens, ↓ 5´-nucleotidase in lymphocytes Risks CVID Pts have a 50-fold ↑ risk for gastric CA, 70% of whom have ↓ gastrin secretion in response to bombesin–a clinical marker for CVID Pts at risk for gastric CA Management IV gammaglobulins

immunodeficiency

a deficiency in the immune system, either that mediated by antibody or T lymphocytes, or both. See also agammaglobulinemia, hypogammaglobulinemia, feline immunodeficiency virus, bovine immunodeficiency virus.

acquired immunodeficiency
see immune deficiency disease.
cancer-associated immunodeficiency
in general, associated with cachexia and debilitation, and also related to the type of neoplasia. Tumor-related effects on the immune system include impaired function of lymphocytes, altered cytokine production and activation of suppressor cell functions.
combined immunodeficiency
common variable immunodeficiency
a term encompassing a heterogeneous group of syndromes, which may be inherited or acquired, characterized by recurring persistent infections and deficiencies of some of the immunoglobulin classes.
congenital immunodeficiency
see immune deficiency disease.
immunodeficiency disease
iatrogenic immunodeficiency
secondary immune deficiency disease.
severe combined immunodeficiency
X-linked immunodeficiency
an inherited form of severe combined immunodeficiency has been reported in dogs. Puppies fail to grow and die from overwhelming infections at an early age.
References in periodicals archive ?
Common variable immunodeficiency and the gastrointestinal tract.
Mutations in TNFRSF13B encoding TACT are associated with common variable immunodeficiency in humans.
Lymphomas of mucosa-associated lymphoid tissue in common variable immunodeficiency.
The researchers analyzed common variable immunodeficiency disorder (CVID), in which weak antibody responses lead to recurrent, often severe bacterial respiratory tract infections.
Retinitis pigmentosa has been associated with a number of systemic diseases, including common variable immunodeficiency state.
New insights into common variable immunodeficiency.
Abstract: A woman with previously undiagnosed common variable immunodeficiency presented with diarrhea and volume depletion.
Initiated Phase 2 clinical trials in rheumatoid arthritis and common variable immunodeficiency (CVID) with apilimod (STA-5326), a potent, selective oral inhibitor of IL-12/23.
octagam is an immune globulin intravenous (human) 5% liquid indicated for treatment of primary humoral immunodeficiency (PI), such as congenital agammaglobulinemia, common variable immunodeficiency, X-linked agammaglobulinemia, Wiskott-Aldrich syndrome and severe combined immunodeficiencies.
These disorders encompass more than 100 diseases, including common variable immunodeficiency, X-linked agammaglobulinemia, and severe combined immunodeficiency.
Sleasman said about a patient in his seventies with common variable immunodeficiency.