MONITORING ALLERGEN EXPOSURE IN ASTHMA - NEW TREATMENT STRATEGIES

The development of monoclonal antibody-based enzyme-linked immunosorbe nt assay technology for measuring environmental allergen exposure has provided a benchmark for assessing the role of indoor allergens in cau sing asthma and other allergic diseases. Epidemiological studies from several parts of the world have shown that immunoglobulin E (IgE)-medi ated sensitization to indoor allergens (mite, cat, dog and cockroach) is a risk factor for asthma attacks. A dose-response relationship betw een allergen exposure and sensitization has been demonstrated for mite allergens, and threshold values for exposure levels leading to sensit ization or to exacerbations of symptoms have been defined. Comparative studies on airborne allergen levels have made it possible to determin e the properties of aeroallergen particles, their concentration in ind oor air, and the relationship to clinical symptoms. Together, these st udies provide strong evidence that allergen exposure plays a causal ro le in the development of bronchial hyperreactivity and of the chronic inflammatory responses seen in patients with asthma. Logically, the pr imary preventive treatment should be allergen avoidance. Through knowl edge of indoor allergen levels, both in dust and in the air, different avoidance strategies have been applied to the various indoor allergen s, and there is increasing evidence of their clinical efficacy. Monito ring allergen levels in patients' houses should improve their understa nding of the role of allergens in asthma and improve compliance with a voidance measures.