Impact of sublingual immunotherapy on seasonal asthma and skin reactivity in children allergic to Parietaria pollen treated with inhaled fluticasone propionate

Background Immunotherapy is a recognized treatment for allergic respiratory diseases. Objective To study the usefulness of immunotherapy in combination with optimal pharmacological therapy. Methods Thirty-eight children (8-14 years) suffering from seasonal asthma+/-rhinoconjunctivitis due to Parietaria poorly controlled by anti-allergic drugs treatment were selected. After randomization according to a double-blind placebo-controlled design they received active sublingual immunotherapy (15 children) or placebo (15 children) for 13 months combined with inhaled fluticasone twice a day during the pollen season. Eight children were taken as control, whereas all patients were instructed to take symptomatic drugs on need. Early and late skin response to the allergen were assessed in all patients before and after treatment. Drug and symptom scores, as well as visual analogue scores (VASs) and Parietaria pollen counts were assessed during the pollen season. Results Groups were well balanced for age, gender, early and late skin response before treatment. Four children dropped out, in one case in relationship with active sublingual immunotherapy (SLIT) administration. Chest and nose symptoms, as well as drug scores and VASs were significantly better in both the active or placebo SLIT+fluticasone (S+F) as compared to the control group (P between <0.001 and 0.043). Eye symptoms were significantly better in the active S+F group as compared to control (P=0.025). The VASs were significantly better in the active S+F group as compared to the placebo S+F group (P=0.037). The early skin response decreased significantly in the active S+F group (P<0.001), whereas the late skin response changed significantly in all groups, with an increase in the placebo+fluticasone group (P=0.019) and in the control group (P=0.037) and a decrease (P<0.0001) in the active S+F group. Conclusion The clinical efficacy of S+F is equal to that of fluticasone alone, but the addition of SLIT has effects also on non-bronchial symptoms.