LOCAL NASAL IMMUNOTHERAPY FOR BIRCH ALLERGIC RHINITIS WITH EXTRACT INPOWDER FORM

Background Traditional subcutaneous immunotherapy has been proved effe ctive in birch pollenosis. It has, however, some drawbacks as systemic reactions, which are rare but important. Local nasal immunotherapy (L NIT) represents a potential safer route of allergen administration. Ob jective To study the clinical efficacy and safety of local nasal immun otherapy by means of an extract in powder form as treatment of birch a llergic rhinitis. Methods Thirty birch allergic patients have been sel ected on the basis of a positive history, skin test, radioallergosorbe nt test assay (RAST) and specific nasal challenge. Two 15 patient grou ps were randomly assigned to the active treatment or to the placebo on e. Treatment lasted 22 weeks (14 for the build-up phase and eight for maintenance period) and symptoms were recorded during the treatment an d the birch pollen season. Results The clinical efficacy of LNIT is su ggested by a significant reduction of medication score only in the tre ated group during the pollen season, although the symptom score was si gnificantly lower in the treated group for I week only. Moreover, a si gnificant increase of specific nasal threshold dose was observed after treatment only in the active treated group. Mild adverse reaction to LNIT, limited to the upper respiratory tract, were reported during the treatment in the active group, but they did not interfere with LNIT s chedule. No asthmatic or systemic reaction were observed. Conclusions This study indicates that LNIT with allergen in powder form has proven clinically effective in the treatment of birch allergic rhinitis. Fur ther studies are needed to establish whether this treatment can be con sidered a real alternative to the traditional subcutaneous immunothera py in birch allergic rhinitis.