Background: Many studies have shown that specific immunotherapy may prevent the development of allergies to new allergens. Recently, however, there have been sporadic reports on the possibility of new allergies developing during immunotherapy. The aim of this study was to evaluate the possibility of the occurrence of food allergy and changes of sIgE concentration in patients sensitive to tree pollen during specific immunotherapy.
Material/methods: We examined 12 patients subjected to desensitization treatment of pollinosis caused by allergy to the pollen of Betulaceae trees, in whom only Bet v 1 sIgE was found in serum prior to immunotherapy. The control group included 8 allergic patients who did not consent to this treatment.
Results: Bet v 2 sIgE was detected after 6 months in 3 patients (25%) and after 18 months in another 2 patients (41.7% total). In 2 cases, oral allergy syndrome (OAS) occurred in the course of therapy. These findings were accompanied by a concomitant decrease in nasal and ocular allergic signs during the birch pollen season in the overwhelming majority of patients (91.7%). In the control group, no serum occurrence of Bet v 2 sIgE was found during the 18-month observation period. Although no OAS signs appeared in any patient, the symptomatic intensity of pollinosis was not reduced.
Conclusions: Due to the limitations of currently used vaccines, new allergies may be induced during immunotherapy. In sporadic cases these may be accompanied by the occurrence of specific clinical manifestations, usually mild.