Advances in upper airway diseases and allergen immunotherapy

The purpose of this review is to highlight important articles on upper airway diseases and immunotherapy that appeared during 2006. Studies from Europe continue to examine the usefulness of the Allergic Rhinitis and its Impact on Asthma classification of allergic rhinitis as intermittent or persistent and its levels of severity as mild or moderate/severe. A number of physical agents were shown to effect nasal inflammation: sudden temperature changes in patients with allergic rhinitis increased eosinophilic inflammation; in children with allergic asthma, the personal exposure to particles <2.5 mu m air pollution correlated with percent of nasal eosinophils and levels of markers of nasal exudation; and in patients who developed rhinorrhea on exposure to cold and windy weather, nasal challenge with cold dry air caused sloughing of nasal epithelial cells. A 3-month double-blind, placebo-controlled study of nasal washes with amphoteracin B showed no benefit in patients with chronic rhinosinusitis. Studies of immunotherapy with grass and dog dander extracts confirmed the need for doses containing 15 to 20 mu g of the major allergen for optimal effectiveness. The protective effect of immunotherapy on the development of asthma in children with allergic rhinitis was shown to still be present 2 years after completion of a 3-year course of treatment. Injection immunotherapy with a moderate dose of house dust mite extract in house dust-sensitive adults with atopic dermatitis reduced symptoms and use of corticosteroids and antihistamines compared with treatment with about 1/1000 of that dose of the same extract. Pretreatment for 9 weeks with the monoclonal anti-IgE antibody omalizumab reduced systemic reactions during rush immunotherapy 5-fold and allowed further build-up at weekly intervals without systemic reactions. A review of sublingual immunotherapy confirmed both efficacy and safety, but evidence for appropriate dosing and for the effectiveness of sublingual immunotherapy employing multiple allergen mixes was still lacking. Two studies with a sublingual grass pollen extract tablet showed a clear dose response and the ability to initiate sublingual immunotherapy without an up-dosing phase. A pilot study with cytosine phosphorothionate quanosine DNA conjugated to the major allergen of ragweed reported impressive improvement in symptoms the first pollen season that persisted during the second pollen season without any further administration of the. conjugate. In conclusion, studies on rhinitis and sinusitis explored the pathophysiology of the disease more than offering new therapeutic approaches. Studies on immunotherapy addressed optimal dosing, but also a variety of safer and more convenient approaches such as reduction of IgE with omalizumab, conjugating allergen to immunostimulatory DNA sequences, or administration by the sublingual route.