[A connection between allergic rhinitis and allergic asthma? The "one-airway-one-disease"-hypothesis]

As outlined in part 1, numerous data from immunologic, genetic and epidemiologic studies point to a systemic link between allergic asthma and rhinitis which can be seen as manifestations of a common atopic syndrome. In part 2 clinical manifestations, diagnostics and most importantly therapeutic options effecting on both nasal and bronchial symptoms will be discussed. Allergen avoidance is the first step in therapeutic management of allergic diseases. Specific immunotherapy (SIT), leukotriene modifying compounds (in Germany exclusively Montelukast), and corticosteroids inhibit inflammation in the epithelium of the upper and the lower airways. Although SIT has a widely accepted indication in the treatment of allergic rhinitis, it is just provisionally recommended for the treatment of asthmatic patients. Most recently Montelukast, a potent leukotriene receptor inhibitor, has been approved for the treatment of asthma as well as for allergic rhinitis. Local administration of corticosteroids requires that they be given both nasally and bronchially. Just on the i. v. or oral route corticosteroids may inhibit the allergic inflammation in both compartments. Newly developed IgE-inhibitor Omalizumab, which has no approval in Germany yet, has been reported to have similar effects. Thus, various therapeutic options are available to treat asthma and rhinitis at the same time. Furthermore, multilateral clinical efficacy of antiinflammatory drugs support the "One-Airway-One-Disease" hypothesis.