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Atopy

Atopy

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Atopy ' onMouseout='HidePop("65179")' href="http://www.absoluteastronomy.com/topics/Greek_language">Greek
Greek language
Greek , an independent branch of the Indo-European family of languages, is the language of the Greeks. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. In its ancient form, it is the language of classical...

 ἀτοπία - placelessness) or atopic syndrome is an allergic hypersensitivity
Hypersensitivity
Hypersensitivity refers to undesirable reactions produced by the normal immune system. Hypersensitivity reactions require a pre-sensitized state of the host. The four-group classification was expounded by P. H. G...

 affecting parts of the body not in direct contact with the allergen
Allergen
An allergen is a nonparasitic antigen capable of stimulating a type-I hypersensitivity reaction in atopic individuals.Most humans mount significant Immunoglobulin E responses only as a defense against parasitic infections. However, some individuals mount an IgE response against common...

.

Causes


It may involve eczema
Eczema
Eczema is a disease in a form of dermatitis, or inflammation of the epidermis. The term eczema is broadly applied to a range of persistent skin conditions. These include dryness and recurring skin rashes that are characterized by one or more of these symptoms: redness, skin edema , itching and...

 (atopic dermatitis
Atopic dermatitis
Atopic dermatitis is an inflammatory, chronically relapsing, non-contagious and pruritic skin disease. It has been given names like "prurigo Besnier," "neurodermitis," "endogenous eczema," "flexural eczema," "infantile eczema," and "prurigo diathsique".-Presentation:The skin of a patient with...

 [AD]), allergic conjunctivitis
Allergic conjunctivitis
Allergic conjunctivitis is inflammation of the conjunctiva due to allergy. Although allergens differ between patients, the most common cause is hay fever. Symptoms consist of redness , oedema of the conjunctiva, itching and increased lacrimation...

, allergic rhinitis and asthma
Asthma
Asthma is a predisposition to chronic inflammation of the lungs in which the airways are reversibly narrowed. Asthma affects 7% of the population of the United States, and 300 million worldwide...

. There appears to be a strong hereditary component
Genetic disorder
A genetic disorder is an illness caused by abnormalities in genes or chromosomes. While some diseases, such as cancer, are due in part to a genetic disorders, they can also be caused by environmental factors. Most disorders are quite rare and affect one person in every several thousands or millions...

. One study concludes that "the general risk of developing AD (3%) and atopy (7%) increases by a factor of two with each first-degree family member already suffering from atopy."

Atopic syndrome can be fatal for those who experience serious allergic reactions, such as anaphylaxis
Anaphylaxis
Anaphylaxis is an acute systemic and severe type I hypersensitivity allergic reaction in humans and other mammals. The term comes from the Greek words ανα ana and φύλαξις phylaxis . Minute amounts of allergens may cause a life-threatening anaphylactic reaction...

, brought on by reactions to food or environment.

The individual components are all caused at least in part by allergy
Allergy
Allergy is a disorder of the immune system often also referred to as atopy. Allergic reactions occur to normally harmless environmental substances known as allergens; these reactions are acquired, predictable, and rapid. Strictly, allergy is one of four forms of hypersensitivity and is called type...

 (type I hypersensitivity reactions). These responses appear after the body is exposed to various allergens, for example specific kinds of food, pollen
Pollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement between the stamens to the pistil of flowering plants or from the male cone to the...

, dander
Dander
Dander is material shed from the body of various animals, similar to dandruff or pet pollen. It may contain scales of dried skin and hair, or feathers. It is a frequent cause of allergy in humans....

 or insect venoms. Although atopy has various definitions, most consistently it is defined by the presence of elevated levels of total and allergen-specific IgE
IGE
IGE is one of the largest MMORPG services companies, with offices in Los Angeles, Miami, and China. IGE is one of the main players in virtual economy services, also known in the MMORPG industry as secondary market...

 in the serum
Blood plasma
Blood plasma is the yellow liquid component of blood, in which the blood cells in whole blood would normally be suspended. It makes up about 55% of the total blood volume. It is mostly water and contains dissolved proteins, glucose, clotting factors, mineral ions, hormones and carbon dioxide...

 of patient, leading to positive skin-prick tests to common allergens.

The multicenter PARSIFAL study
PARSIFAL study
similar name: PARSIFAL Project EUPARSIFAL was a multicenter study conducted among Steiner school children in 2006...

 in 2006, involving 6630 children age 5 to 13 in 5 European countries, suggested that restrictive use of antibiotic
Antibiotic
In common usage, an antibiotic is a substance or compound that kills or inhibits the growth of bacteria...

s and antipyretic
Antipyretic
Antipyretics are drugs that reduce body temperature in situations such as fever. However, they will not affect the normal body temperature if one does not have a fever....

s, are associated with a reduced risk of allergic disease in children.

Symptoms


Some symptoms, from an atopy questionnaire:
  • Cracks in the skin under the earlobe
    Earlobe
    The earlobe is, in humans and many other animals, the soft lower part of the external ear. It is the lowermost portion of the human pinna, projecting below the antitragus. The earlobe is composed of tough areolar and adipose connective tissues, lacking the firmness and elasticity of the rest of...

  • Eczema
    Eczema
    Eczema is a disease in a form of dermatitis, or inflammation of the epidermis. The term eczema is broadly applied to a range of persistent skin conditions. These include dryness and recurring skin rashes that are characterized by one or more of these symptoms: redness, skin edema , itching and...

    • In elbow flexures and/or hollow of the knees
    • Nipple eczema
    • Neurodermatitis
      Neurodermatitis
      Neurodermatitis is a term used to describe various forms of eczema:* Lichen simplex chronicus and its cousin, prurigo nodularis; these are types of eczema that are thought to be self-caused, as by habitual scratching, or have unexplained origin, and are mostly localized; the older term was...

    • Subtype Dyshidrosis
      Dyshidrosis
      Dyshidrosis, also termed Dyshidrotic Eczema, Pompholyx, Acute vesiculobullous hand eczema, and Dyshidrotic Dermatitis, is a skin condition that is characterized by small blisters on the hands or feet...

  • Keratosis pilaris
    Keratosis pilaris
    Keratosis pilaris is a very common genetic follicular condition that is manifested by the appearance of rough bumps on the skin, hence referred to as chicken skin...

  • Perlèche
  • Conjunctivitis
    Conjunctivitis
    Conjunctivitis is an inflammation of the conjunctiva , most commonly due to an allergic reaction or an infection...

  • Chronic or seasonal rhinitis
    Rhinitis
    Rhinitis , commonly known as a runny nose, is the medical term describing irritation and inflammation of some internal areas of the nose. The primary symptom of rhinitis is nasal dripping. It is caused by chronic or acute inflammation of the mucous membrane of the nose due to viruses, bacteria or...


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