Determination of eosinophil rate after nasal provocation test in allergic rhinitis diagnosis

After nasal provocation test in patients with allergic rhinitis, using the allergen they were sensitized to, we have observed: 1) an increase in the percentage of nasal eosinophils after 2, 3, 24 and 48 hours; 2) sneezes, mainly in the first 30 minutes; 3) nasal obstruction in the first three hours; 4) absence of rhinorrhea, but not in all the patients; and 5) no predominance of nasal, auricular and/or palatine pruritus at any time. When patients without rhinitis, or with allergic rhinitis were stimulated using a pneumoallergen they were not sensitized to, no significative increase in the nasal eosinophils percentage was found. No symptoms were observed either. So, we can conclude that nasal secretion samples, for eosinophilia percentage determination, should be taken from 2 to 48 hours after nasal provocation, and that the most frequent symptoms, which are probably related to cellular changes, are nasal obstruction and sneezes.