Résumé
BACKGROUND: Allergic rhinitis is characterized by eosinophil inflammation. Allergic inflammation may induce susceptibility to respiratory infections (RI). House dust mite (HDM) sensitization is very frequent in childhood. Allergen immunotherapy may cure allergy as it restores a physiologic immune and clinical tolerance to allergen and exerts anti-inflammatory activity. OBJECTIVE: This study investigated whether six-month high-dose, such as 300 IR (index of reactivity), HDM-sublingual immunotherapy (SLIT) could affect RI in allergic children. METHODS: Globally, 40 HDM allergic children (18 males; mean age, 9.3 years) were subdivided in 2 groups: 20 treated by symptomatic drugs (group 1) and 20 by high-dose HDM-SLIT (group 2), since September 2012 to April 2013. The daily maintenance dose of HDM-SLIT was 4 pressures corresponding to 24, 4.8, and 60 µg, respectively of the major allergens Dermatophagoides pteronyssinus (Der p) 1, Der p 2, and Dermatophagoides farinae (Der f) 1. RI was diagnosed when at least 2 symptoms or signs, and fever were present for at least 48 hours. A family pediatrician provided diagnosis on a clinical ground. RESULTS: SLIT-treated children had significantly (p = 0.01) less RI episodes (3.5) than control group (5.45). About secondary outcomes, SLIT-treated children had less episodes of pharyngo-tonsillitis (p < 0.05) and bronchitis (p < 0.005), and snoring (p < 0.05) than control group. In addition, SLIT-treated children had less fever (p < 0.01) and took fewer medications, such as antibiotics (p < 0.05) and fever-reducers (p < 0.01), than control group. CONCLUSION: This preliminary study might suggest that also a short course (6 months) of high-dose SLIT, titrated in µg of major allergens, could reduce RI in allergic children.
Sujets)
Enfant , Humains , Mâle , Allergènes , Antibactériens , Bronchite , Dermatophagoides farinae , Dermatophagoides pteronyssinus , Désensibilisation immunologique , Diagnostic , Poussière , Granulocytes éosinophiles , Fièvre , Hypersensibilité , Immunothérapie , Inflammation , Mites (acariens) , Pyroglyphidae , Infections de l'appareil respiratoire , Rhinite allergique , Ronflement , Immunothérapie sublingualeRésumé
Allergen-specific immunotherapy is aimed at modifying the natural history of allergy by inducing tolerance to the causative allergen. In its traditional, subcutaneous form, immunotherapy has complete evidence of efficacy in allergic asthma. However, subcutaneous immunotherapy [SCIT] has a major flaw in side effects, and especially in possible anaphylactic reactions, and this prompted the search for safer ways of administration of allergen extracts. Sublingual immunotherapy [SLIT] has met such need while maintaining a clinical efficacy comparable to SCIT. In fact, the safety profile, as outlined by a systematic revision of the available literature, was substantially free from serious systemic reactions. A number of meta-analyses clearly showed that SLIT is effective in allergic rhinitis by significantly reducing the clinical symptoms and the use of anti-allergic drugs, while the efficacy in allergic asthma is still debated, with some meta-analyses showing clear effectiveness but other giving contrasting results. Besides the efficacy on symptoms, the preventive activity and the cost-effectiveness are important outcomes of SLIT in asthma. The needs to meet include more data on efficacy in house dust mite asthma, optimal techniques of administration and, as previously done with SCIT, introduction of adjuvants able to enhance the immunologic response and use of recombinant allergens