Immunodeficiency

Immunodeficiency is in medical terminology used synonymously with the terms immunoincompetence , immunodeficiency , immunodeficiency or immunodeficiency and is a collective term for different diseases of the immune system that are characterized by a temporary or irreversible weakening of the defensive function, ie the ability to against invading pathogens to defend . As a result of the increased susceptibility to infection (“low resistance syndrome”), more infectious diseases occur, which can also be more difficult.

Classification

The classification of immunodeficiencies can be based on various criteria. If defense cells are predominantly affected (i.e. the cellular immune response ), one speaks of a cellular immunodeficiency , while antibodies and other immune-active proteins (i.e. the humoral immune response ) are more likely to be referred to as a humoral immune defect . Often both systems are affected. One then speaks of a combined immunodeficiency .

On the other hand, the classification can be based on the time of the disease. If the immunodeficiency has existed since birth due to a genetic defect or a malformation, this is called a congenital immunodeficiency ( primary immunodeficiency, PID ); if the disorder occurs later, an acquired immunodeficiency ( secondary immunodeficiency, SID ).

causes

Congenital immune deficiencies are relatively rare diseases. For most of them, at least the gene location has now been identified on which the disturbed genetic information is located. For many of these diseases we even know the gene product whose function is disturbed. For example, in immunodeficiency due to interleukin-1 receptor-associated kinase-4 deficiency .

The most common acquired immunodeficiency worldwide is AIDS , caused by the HI virus . An immunodeficiency is also caused by a disease of the bone marrow that is associated with impaired blood formation - e.g. B. leukemia or neutropenia (with a lack of functional granulocytes as in leukocytopenia, agranulocytosis and immature cell leukemia). Also a malnutrition, connected z. B. with a vitamin deficiency can lead to an acquired reduced function of the immune system. An inadequate function of the RHS system can increase the susceptibility to infections due to vitamin C deficiency, diabetes, leukemia and reticulosis.

The cause of an iatrogenic (= caused by a doctor) immune deficiency is a medical treatment that stimulates the immune system

• intentionally suppressed - immunosuppression in an autoimmune disease or to prevent rejection after an organ transplant -

or

• as a side effect harms, e.g. B. as part of cancer therapy with certain drugs ( cytostatics ) or radiation .

Diagnosis

An immunodeficiency is diagnosed by first doing a series of screening tests in the blood. Depending on the result, more complex functional tests of the individual cell rows of the immune system are then carried out. If an immunodeficiency has already occurred in a family, a prenatal diagnosis by examining the amniotic fluid, the chorionic villi or a blood sample from the fetus is also possible.

therapy

In the case of some congenital immunodeficiencies, stem cell transplantation is an option for treating the cause, as it is used to transfer a new, healthy immune system. As symptomatic therapy, especially for humoral and combined immunodeficiencies, regular administration of antibody preparations obtained from foreign blood is available. In this way, an antibody deficiency can be compensated. In addition, consistent antibacterial (against bacteria ) and antifungal (against fungi ) drug therapy should prevent the development of opportunistic infections . Opportunistic infections are infections with pathogens that actually occur everywhere and do not cause disease in healthy ( immunocompetent ) people because the immune system is able to protect itself against these microorganisms.

Vaccinations

Vaccinations for people with immunodeficiency are a special case: On the one hand, live vaccines in which pathogens - albeit attenuated ("attenuated") - are administered in a targeted manner, do not result in the intended protection against the infectious disease in question, but such a disease is triggered. Here the vaccination indication depends on the type and severity of the immunodeficiency. On the other hand, the administration of inactivated vaccines may not (sufficiently) lead to the build-up of immune protection. Then closer vaccination intervals should be considered.

See also

• Purine nucleoside phosphorylase
• Severe Combined Immunodeficiency

literature

• U. Wahn, R. Seger, V. Wahn, GA Holländer: Pediatric Allergology and Immunology, 4th Edition, Elsevier, Munich 2005, ISBN 3-437-21311-3 .
• S1 guidelines for the diagnosis of primary immunodeficiency (PGD) of the German Society for Pediatric and Adolescent Medicine. In: AWMF online (as of 2011)

Web links

• ImmunDefektZentrum of the Charité Berlin
• V. Wahn, S. Ehl, T. Niehues: susceptibility to infection - attempt at a definition , ImmunDefektZentrum of the Charité Berlin
• Information sheets on various forms of immunodeficiency from the Center for Chronic Immunodeficiency at the Freiburg University Medical Center
• European Society for Immunodeficiencies (including the European database that includes PGD patients)
• dsai eV - German patient organization for congenital immunodeficiencies
• Self-help group for primary immunodeficiencies Austria (ÖSPID)

Individual evidence

1. ^ Rudolf Gross : Diseases of the white blood cells (leukocytopoiesis) and the blood-forming organs. In: Rudolf Gross, Paul Schölmerich , Wolfgang Gerok (Eds.): 1000 memoranda of internal medicine. Schattauer, Stuttgart / New York 1971; 4th, completely revised edition, ibid. 1989 (= UTB für Wissenschaft / Uni-Taschenbücher. Volume 522), ISBN 3-7945-1282-0 , pp. 45–50, here: p. 46.
2. ^ Rudolf Gross: Diseases of the white blood cells (leukocytopoiesis) and the blood-forming organs. 1989, p. 46.

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !