Chapter 3. Inhalant Allergens
The diagnosis of inhalant allergy can be made by prick skin testing or quantitative serum IgE levels against specific inhalant allergens. Prolonged avoidance of house dust mites in atopic dermatitis patients known to be allergic to dust mites has been reported to result in improvement of their skin disease. Avoidance measures include use of house dust mite-proof encasings on pillows, mattresses, and boxsprings; washing bedding in hot water weekly; removal of bedroom carpeting; and decreasing indoor humidity levels.
Most food allergic children outgrow their food hypersensitivity in the first few years of life, making it less relevant as a trigger in older patients. In older children and adults, pruritus and skin lesions can develop after intranasal or bronchial inhalation challenge with aeroallergens in atopic dermatitis patients who produce IgE to the relevant inhalant allergen. Application of inhalant allergens (e.g. house dust mites, weed or grass pollen, animal danders and molds) to uninvolved atopic skin elicits eczematoid reactions in 30-50% of patients with atopic dermatitis. In contrast, similar patch tests are usually negative in patients with respiratory allergy and healthy volunteers. The level of IgE antibody to inhalant allergens has also been shown to be associated with the severity of AD.