BACKGROUND In pediatric ages, sublingual immunotherapy (SLIT) allows allergic children to approach the inhaling desensitizing therapy. However, SLIT causes quite a few compliance problems and sometimes it is difficult to carry it out for the required long term. The alternative is subcutaneous immunotherapy (SCIT), commonly performed with a syringe. This technique hasn't changed much in time and it is not without risks or discomfort. This has led to the search for alternative ways of vaccine administration, in order to reduce discomfort to children by improving compliance and diminishing the potential risks of adverse reactions. OBJECTIVE The study aimed to assess the patient's perceived pain and the safety of a new way of administration of SCIT, with a needleless device. METHODS Children with grass or mite-induced allergic rhinoconjunctivitis and/ or bronchial asthma were prescribed a glutaraldehyde-polymerized allergenic extract (Allergovac Polymeryzed®, Bial Aristegui, Italy). Each dose was divided in two parts: half injected with the traditional syringe (dose A), half in the other arm with a needleless device (Injex, Greytree, Ross on Wye, UK; dose B). Patients were blindfolded. The perceived pain and the difficulties of the procedure were registered on a dedicated VAS scale immediately (time 1) and 20 minutes after the first injection (time 20). Also, we evaluated the occurrence of occasional adverse events during such procedure and we assessed the perceived difficulty by the doctor administering with such method. RESULTS 39 patients, aged 5-18 years, were recruited and assessed. All patients completed the study, which involved 468 grass pollen AIT SCIT doses, of which 234 with needleless device. At time 1, the use of the needleless device led to an 88% reduction of the pain perception average rate (from 16,8 to 1,97). The difficulty for the technician to make the inoculum was also analyzed (expressed by an increasing rate, from 0 to 4). In all 6 doses, for each child, the difficulty rate 2 relates to an almost constant number of patients, while the highest difficulty rates (grade 3 and grade 4) gradually decrease (until they disappear). CONCLUSIONS The vaccine administration with needleless device has various advantages and it ensures a better acceptance in comparison with administration by traditional SCIT. This is important in order to start the immunotherapy at an early stage, as it is recommended by the most recent studies, so that the natural evolution of the allergic disease can be immediately modified. The new technique ensures a higher safety both for the vaccinator and for the patient, with a better acceptance of the procedure by the patient and therefore a better and wider compliance to the vaccination schedules.
