Background: Navarre, in Northern Spain, is an area with moderate exposure to olive and ash tree pollen.

Objective: To assess the relevance of ash as a cause of pollinosis in our region.

Methods: The study sample comprised 85 patients from Navarre with clinical symptoms of pollinosis. Specific immunoglobulin E (sIgE) was determined to Fra e 1, Ole e 1, and a mixture of amino- and carboxy-terminal domains of Ole e 9 (Ole e 9 NC) (ADVIA-Centaur). At the same time, the presence of sIgE to other pollen allergens was studied. Prick tests were performed with ash pollen (n=33) and olive pollen (n=85) and the symptomatic period was recorded (n=85). As a control group, we studied the serum of 98 patients with olive pollen allergy, intense exposure to olive pollen, and no exposure to ash.

Results: Sensitization to Oleaceae was detected in 24/85 patients in the study group (28.2%). In this group, the mean (SD) level of IgE to Fra e 1 was 8.5 (10) kUA/L and to Ole e 1 6.07 (7.88) kUA/L (P<.001). In the control group, these figures were 103.64 (132.19) kUA/L and 86.43 (118.5) kUA/L (P<.001), respectively. In all patients with positive sIgE to Fra e 1, IgE to Ole e 1 was also detected (concordance index, κ=1), both in the study group and in the control group. Patients who were sensitized to Fra e 1 did not present a longer symptomatic period and their symptoms did not have an earlier onset.

Conclusion: We did not find evidence of clinically relevant sensitization to ash in Navarre.

Key words: Allergen. Ash pollen. Olive pollen. Pollinosis.