Environmental allergens

Atopic Related to a genetically determined hypersensitivity to environmental allergens allergic. 

In general, treatment of ocular allergic disease is based on symptoms, severity, and characteristics of the allergic reaction. A stepped-care approach to therapy has been advocated, whereby treatment aggressiveness is tailored to the level of disease. When possible, avoidance of environmental allergens such as pollen, dust, and grasses is a key fector in management. 

An atopic person has reaginic antibodies directed against common environmental allergens, and since immunoglobulin E (IgE) is the most important reaginic antibody in man its measurement is relevant to both clinical allergists and immunologists. 

The United States incidence varies ethnically from 7.3% in white non-Hispanic, 9.4% in black non-Hispanic, to 14.1% in Puerto Ricans [4]. In addition, non-Hispanic blacks are five times more likely to visit the emergency room for asthma exacerbation and three times more likely to be hospitalized and die from asthma than whites. The ethnic differences in prevalence and severity of asthma in the United States could be caused by preexisting risk factors, including genetics, environmental allergen exposure, and socioeconomic level [4]. 

Prescott SL, Macaubas C, Holt BJ, Smallacombe T, Loh R, Sly PD, Holt PG Transplacental priming of the human immune system to environmental allergens Universal skewing of initial T-cell responses towards the Th-2 cytokine profile. Immunol J 1998 160 4730-4737. 

Holt PG, Macaubas C Development of long term tolerance versus sensitisation to environmental allergens during the perinatal period. Curr Opin Immunol 1997 9 782-787. 

Atopy, defined either by a positive skin prick test or presence of IgE antibodies in serum to common environmental allergens, may be used as a criterion for increased risk of development of occupational allergy. Exclusion of workers with a positive skin prick test can, however, mean denying employment to approximately one third of job applicants, only a proportion of whom would develop occupational asthma [17]. More stringent criteria for IgE sensitisation... 

The most common form of asthma is allergic asthma (atopic or extrinsic asthma), and it is associated with environmental allergens, such as plant pollens, house dust mites (Dermatophagoides farinae), domestic pet dander, molds, and foods. The less common form, intrinsic asthma, has no known allergic cause and usually occurs in adults older than 35 years. Intrinsic asthma may result from an autonomic dysfunction characterized by excess cholinergic... 

Gangyr V, Simons EE, HayGlass KT. lP-10 mediated reinforcement of human type 1 cytokine synthesis to environmental allergens among non-atopic subjects. Int Arch AUergy Inununol 1999 118 387-395. 

It is important to recognize that delayed chemical allergy can occur even some time afto" the chemical has been removed. Contact with poison ivy is a familiar example of an exposure that causes a delayed allergic reaction. Also, just as people vary widely in their susceptibility to sensitization by environmental allergens such as dust and poUen, individuals may also exhibit wide differences in their sensitivity to laboratory chemicals. Examples of substances that may cause allergic reactions in some individuals include diazomethane, dicyclohexylcarbodiimide, formaldehyde, various isocyanates, benzyUc and aUyUc halides, and certain phenol derivatives. 

The association of household use of hypochlorite with atopic sensitization, allergic disease, and respiratory health status has been assessed in 3626 participants in the European Community Respiratory Health Survey II. Specific serum IgE to four environmental allergens was available and all the participants did the cleaning in their own homes [65 ]. The use of... 

Some adverse effects have been reported for echinacea. For example, more than 50 cases of allergy were detected in Australia and were linked to the use of echinacea preparations. Symptoms included acute asthma, maculo-papular rash/urticaria, and anaphylaxis. There was evidence of the involvement of an echinacea-binding IgE in ca. 50% of the cases and the possibility of cross-reactivity between echinacea and other environmental allergens was proposed. ... 

Those children who are more likely to have asthma appear to show evidence of an altered immunological process, i.e., they become sensitized to allergens and other antigens early in life. The association among environmental allergens. 

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