Immunodeficiency (or immune deficiency ) is a condition in which the ability of the immune system to fight infectious diseases and cancer is compromised or nonexistent. Most cases of immunodeficiency are obtained ("secondary") due to extrinsic factors affecting the patient's immune system. Examples of these extrinsic factors include HIV infection, extreme age, and environmental factors, such as nutrition. In a clinical setting, immunosuppression by some drugs, such as steroids, may be adverse effects or intended purposes of treatment. Examples of such use are in organ transplant surgery as a measure of anti-rejection and in patients suffering from overactive immune systems, such as in autoimmune diseases. Some people are born with intrinsic defects in their immune system, or primary immunodeficiency. A person who has immunodeficiency in any form is said to be immunocompromised . People who are immunocompromised may be highly susceptible to opportunistic infections, other than normal infections that can affect everyone. Immunodeficiency also decreases cancer immunosurveillance, in which the immune system scans the body's cells and kills the neoplastic.
Video Immunodeficiency
Type
By the affected component
- Lack of humoral immune (including deficiency or dysfunction of the B cell), with signs or symptoms depending on the cause, but generally include signs hipogammaglobulinemia (reduction of one or more types of antibody) with presentations including respiratory infections mild recurrent, and/or agammaglobulinemia (deficiency of all or most antibody production) leading to severe and often fatal infection.
- Lack of T cells, often leading to secondary disorders such as acquired immune deficiency syndrome (AIDS).
- Lack of granulocytes , including a reduction in the number of granulocytes (called granulocytopenia or, if none, agranulocytosis), such as neutrophil granulocytes (called neutropenia). Lack of granulocytes also includes decreased function of individual granulocytes, as in chronic granulomatous disease.
- Asplenia, where there is no spleen function
- Complementary weakness is where the complementary system functions less
In fact, immunodeficiency often affects several components, with important examples including severe combined immunodeficiency (primary) and acquired immune deficiency syndrome (secondary).
Primary or secondary
The difference between primary and secondary immunodeficiencies is based on, respectively, whether the cause originates within the immune system itself or, in turn, due to a lack of a support component or external degradation factor.
Primary immunodeficiency
A number of rare diseases have a high susceptibility to infection since childhood. Primary immunodeficiency is also known as congenital immunodeficiencies. Many of these disorders are hereditary and autosomal or X-linked recessive. There are more than 80 recognized primary immunodeficiency syndromes; they are generally grouped by parts of the damaged immune system, such as lymphocytes or granulocytes.
Treatment of primary immunodeficiencies depends on the nature of the defect, and may involve infusion of antibodies, long-term antibiotics and (in some cases) stem cell transplantation. Characteristics of poor and/or impaired antibody function may be associated with diseases such as X-Linked Agammaglobulinemia and Common Variable Immune Deficiency
Secondary Immunodeficiencies
Secondary Immunodeficiencies, also known as acquired immunodeficiencies, can be produced from various immunosuppressive agents, for example, malnutrition, aging, certain drugs (eg, chemotherapy, antirheumatic drugs that alter disease, medications immunosuppressive after organ transplant, glucocorticoid) and environmental toxins such as mercury and other heavy metals, pesticides and petrochemicals such as styrene, dichlorobenzene, xylene, and ethylphenol. For drugs, the term immunosuppression generally refers to the harmful effects of both the beneficial and the potential of the decline in immune system function, whereas the term immunodeficiency generally refers solely to the adverse effects of improvement risk of infection.
Many specific diseases directly or indirectly cause immunosuppression. These include many types of cancers, especially from the bone marrow and blood cells (leukemia, lymphoma, multiple myeloma), and certain chronic infections. Immunodeficiency is also a feature of acquired immunodeficiency syndrome (AIDS), which is caused by human immunodeficiency virus (HIV). HIV directly infects a small number of helper T cells, and also impairs other immune system responses indirectly.
Various hormonal and metabolic disorders can also lead to immune deficiency including anemia, hypothyroidism, diabetes and hypoglycemia.
Smoking, alcoholism, and drug abuse also suppress the immune response.
Maps Immunodeficiency
Immunodeficiency and autoimmunity
There are a large number of immunodeficiency syndromes that exhibit clinical and laboratory characteristics of autoimmunity. The reduced ability of the immune system to clear the infection in these patients may be responsible for causing autoimmunity through continued immune system activation.
One example is a common variable immunodeficiency (CVID) in which some autoimmune diseases are seen, for example, inflammatory bowel disease, autoimmune thrombocytopenia and autoimmune thyroid disease. Familial hemophagocytic lymphohistiocytosis, an autosomal recessive primary immunodeficiency, is another example. Pansitopenia, rash, lymphadenopathy and hepatosplenomegaly are common in these patients. The presence of some viral infections is not clear because the lack of perforin is considered responsible. In addition to chronic and/or recurrent infections many autoimmune diseases including arthritis, autoimmune hemolytic anemia, scleroderma and type 1 diabetes are also seen in X-linked agammaglobulinemia (XLA). Repeated bacterial and fungal infections and chronic inflammation of the gut and lungs are seen in chronic granulomatous disease (CGD) as well. CGD is caused by a decrease in the production of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase by neutrophils. HAGomorphic RAG mutations are seen in patients with midline granulomatous disease; autoimmune disorders often seen in patients with granulomatosis with polyangiitis (Wegner's disease) and NK/T cell lymphoma. Wiskott-Aldrich syndrome (WAS) patients also present with eczema, autoimmune manifestations, recurrent bacterial infections and lymphoma. In autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) also autoimmunity and coexistence infections: organ-specific autoimmune manifestations (eg, hypoparathyroidism and adrenocortical failure) and chronic mucocutaneous candidiasis. Finally, IgA deficiency is also sometimes associated with the development of autoimmune and atopic phenomena.
Cause
The causes of immunodeficiency vary depending on the nature of the disorder. The cause may be genetic or acquired by malnutrition and poor sanitary conditions. Just for some genetic cause, the right genes are known. Although there is no true discrimination against whom this disease affects, genes are passed from mother to child, and sometimes from father to child. Women tend to show no symptoms because their second X chromosome has no mutation when the man is symptomatic, because it has one X chromosome.
Treatment
Available treatments fall into two modalities: treating infections and boosting the immune system.
Prevention of Pneumocystis pneumonia using trimethoprim/sulfamethoxazole is useful in those who are immunocompromised. In the early 1950s Immunoglobulin (Ig) was used by physicians to treat patients with primary immunodeficiency via intramuscular injection. Ig replacement therapy is an infusion that can be administered subcutaneously or intravenously, resulting in higher Ig levels for about three to four weeks, although this varies with each patient.
Prognosis
The prognosis depends on the nature and severity of the condition. Some deficiencies cause premature death (before one year of age), others with or without treatment are lifelong conditions that lead to minimal death or morbidity. Newer stem cell transplantation technologies can lead to genetically weakened gene-based treatments and fatal genetic immune deficiencies. The prognosis of acquired immune deficiency depends on avoiding or treating agents or conditions of cause (such as AIDS).
See also
- Acquired immune deficiency syndrome (AIDS or HIV), a viral disease sometimes used everyday as a synonym for immune deficiency
- Immune disorders
- Autoimmune disease, immune response to self protein
- Allergies, immune responses to non-self-harmful proteins
- Histamine
- Immunosenescence, age-related immunity deficiency
- Steroids, commonly prescribed drugs such as prednisone that suppress the immune system
- Immune system
- Immunology
References
External links
- Immun Deficiency Foundation
- Society of European Immunodeficiencies
Source of the article : Wikipedia
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