Oleaceae-induced pollinosis in an area with exposure to olive and ash trees.

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) kU(A)/L and to Ole e 16.07 (7.88) kU(A)/L (P < .001). In the control group, these figures were 103.64 (132.19) kU(A)/L and 86.43 (118.5) kU(A)/L (P < .001), respectively. In all patients with positive sIgE to Fra e 1, IgE to Ole e 1 was also detected (concordance index, kappa = 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.