Allergen-induced specific and non-specific nasal reactions. Reciprocal relationship and inhibition by topical glucocorticosteroids.

The correlation between allergen-induced specific and non-specific (histamine) nasal reactions was studied, especially as regards topical glucocorticosteroid effects on the non-specific reactions. Thirteen patients with strictly seasonal allergic rhinitis participated. A nasal challenge with histamine and three increasing doses of allergen was performed on the first day. The patients were rechallenged 24 h later with the same histamine dose and the lowest allergen dose from the previous day. The same 2-day challenge was also performed after pretreatment for one week with budesonide in 8 of these patients. Symptom scores were recorded. The N-alpha-tosyl-L-arginine-methyl-esterase (TAME esterase) activity in nasal lavages was determined. The nasal symptoms and the TAME-esterase activity increased at rechallenge for both histamine and allergen, compared with the initial challenge. The mean ( +/- SE) composite nasal symptom score after histamine increased from 3.5 +/- 0.49 to 4.9 +/- 0.35 (p less than 0.01) and after allergen from 1.62 +/- 0.3 to 3.2 +/- 0.5 (p less than 0.01) at rechallenge. Similar increases were recorded for the TAME-esterase activity. A close correlation between the allergen-induced increase in specific (allergen) and non-specific (histamine) reactivity was found (r = 0.7, p less than 0.01, composite nasal symptom score). Treatment with topical glucocorticosteroids abolished the allergen-induced increase in both specific (p less than 0.001) and non-specific (histamine) (p less than 0.01) nasal reactivity.