Science and Profession (Magill’s Medical Guide, Sixth Edition)
Immunopathology is the subdiscipline of immunology that deals with the four basic types of pathologies caused by the immune system: autoimmune disorders, congenital immunodeficiencies, acquired immunodeficiencies, and hypersensitivity reactions. Physicians who deal with such disorders are trained in immunology and/or pathology.
Autoimmune disorders are those in which the body fails to distinguish between self and nonself, leading to attack by the immune system on the tissues or organs of the body. There are many autoimmune disorders, and the symptoms are extremely varied, depending on the site and extent of the attack. Some disorders are tissue-specific, while others affect tissues and organs throughout the body. Examples of autoimmune disorders are multiple sclerosis (MS), systemic lupus erythematosus (SLE), and myasthenia gravis.
Congenital (primary) immunodeficiencies are those conditions in which there is an absence or a failure of the immune system at birth. Often they are the result of a failure of one or more components of the immune system to develop during the fetal stages. Most congenital deficiencies have a genetic basis. An example of a primary immunodeficiency disorder is DiGeorge syndrome, in which T cells are deficient as a result of a developmental problem of the thymus. The most severe of these disorders is severe combined immunodeficiency disorder (SCID), in which both B and T cells do not...
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Diagnostic and Treatment Techniques (Magill’s Medical Guide, Sixth Edition)
Specialists who deal with immunopathologies may provide treatments that vary widely, as do the disorders themselves. The goal of all therapy is to restore the immune system to its normal balance so that it can continue to protect the body from the constant barrage of invading microorganisms. Individuals with immune system deficiencies are told to avoid contact with other individuals as much as possible, since most viruses and bacteria are spread through personal contact. Prophylactic regimens of antibiotics, antivirals, and antifungals are helpful in most of those with immunodeficiencies, but in those with more severe forms, bone marrow transplants are the treatment of choice. The use of passive immunization—transferring antibodies from healthy individuals into those with immunodeficiencies—is helpful in some cases. In acquired immunodeficiency syndrome (AIDS), drug combinations, or “cocktails,” are aimed at suppressing replication of HIV, which attacks the T cells and keeps them from functioning.
Because most hypersensitivity reactions are temporary immunopathologies, their treatment involves short-term therapies to restore balance to the system. Antihistamines, for instance, help many allergy sufferers, as do air purifiers and lifestyle changes. Careful tissue and blood typing can eliminate or lower the instances of the other types of hypersensitivities.
Treatment for autoimmune disorders...
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Perspective and Prospects (Magill’s Medical Guide, Sixth Edition)
Since immunology itself is a field that is still in its infancy, recognition of immune disorders and their treatments is relatively new. Autoimmunity was first described by Paul Ehrlich at the turn of the twentieth century, and he called the phenomenon “horror autotoxicus,” a name that struck fear in patients and providers alike. Hypersensitivitiy reactions, especially allergies, were recognized hundreds of years ago, and various chemical prescriptions were used to control the symptoms, but it was not until the mid-twentieth century that the molecular basis of allergies began to be understood. Immunodeficiencies are still being described, and the understanding of their basis is quite incomplete.
Some immunodeficiencies, if detected early enough, may be candidates for future gene therapy. In those cases where a single gene defect can be identified, introduction of the functional gene into the developing tissue may be able to reverse the course of the disease, partially or completely. Other options include transplantation of the thymus or bone marrow in order to allow normal functioning of the immune system components.
One of the most exciting potential treatments for secondary immunodeficiencies is vaccination. The ability to block AIDS through early immunization looks promising, although still many years away from use.
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For Further Information: (Magill’s Medical Guide, Sixth Edition)
Abbas, Abul K., and Andrew H. Lichtman. Basic Immunology: Functions and Disorders of the Immune System. 2d ed. Philadelphia: Saunders/Elsevier, 2006. An easy-to-read introduction to the human immune system. Includes excellent figures and a thorough glossary.
Fischer, A. M., et al. “Naturally Occurring Primary Deficiencies of the Immune System.” Annual Review of Immunology 15 (1997): 93-124. A good, although somewhat technical, review of primary deficiencies and the literature in the field.
Janeway, Charles A., Jr., et al. Immunobiology: The Immune System in Health and Disease. 6th ed. New York: Garland Science, 2005. A classic undergraduate text on immunology, containing well-written and thorough chapters on failures of host-defense mechanisms, allergy, and hypersensitivity.
National Institutes of Health. http://www.nih.gov. This Web site contains dozens of easy-to-read pamphlets that are useful for those needing basic information on immune system disorders, including Understanding the Immune System, Something in the Air: Airborne Allergens, and Food Allergy: An Overview.
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