[Comparison of nasal histamine and allergen provocations in patients with allergic rhinitis].

OBJECTIVES: We evaluated the effects of histamine and allergen provocations in the nasal mucosa. PATIENTS AND METHODS: Nasal provocations were performed with extracts of histamine, Dermatophagoides pteronyssinus (Dp) and mixed grass pollen (Mg) in patients with perennial and seasonal allergic rhinitis and in healthy subjects. Nasal airway resistance (NAR), the amount of secretions, and the number of sneezes were recorded and evaluated. RESULTS: Regarding NAR, histamine provocation resulted in a significant difference compared to Dp provocation, but the difference was not significant when compared to Mg provocation. Only associated antigen provocation caused a significant increase in secretion. No significantly different effect on sneezing was detected between allergens and histamine. Considering total scores, histamine did not cause an increase in nasal reactivity in healthy subjects. A significant but slight difference was found between allergens and histamine in terms of nasal hyperreactivity in patients with allergic rhinitis. CONCLUSION: As there is a weakly significant difference between allergens and histamine in terms of nasal hyperreactivity in patients with allergic rhinitis, histamine provocation can be used in conditions where allergen provocation is not available.