Systemic reactions to specific immunotherapy in children with respiratory allergy: a prospective study

Abstract

The aim of this multi-centre prospective study was to evaluate the prevalence of systemic reactions to specific immunotherapy in children with allergic asthma and or rhinitis. One thousand and fifty-six children (653 boys and 403 girls), median age 8.5 years, were enrolled in this three-year prospective study. All the children were treated with injections of the following allergenic extracts: 689 of house dust mite, 291 of grass, 109 of Parietaria, 13 of Alternaria, 6 of Artemisia and 11 of Olea. Among 1056 treated children, 41 (3.7%) had systemic reactions: 40 children (3.7%) experienced mild symptoms such as asthma and/or urticaria, and only one shock (0.08%). A total of 47,247 injections were administered, and the rate of systemic reactions, according to the number of total injections was only 0.08%. According to the allergenic extract, systemic reactions occurred in 29/689 children (4.2%) treated with house dust mites extract (0.09% of the injections), in 9/291 children (3.1%) treated with grass extract (0.07% of the injections) and in 3/109 children (2.8%) treated with Parietaria extract (0.06% of the injections). The prevalence of systemic reactions was significantly higher (p < 0.0001) in the children treated with house dust mite extract in comparison with those treated with pollen extracts. All the systemic reactions appeared within 30 minutes following the administration of the extract and occurred in 37/41 cases (90.2%) with the same dose, previously tolerated. Most reactions were mild, and were readily controlled by immediate emergency treatment. There was no need for hospitalization.(ABSTRACT TRUNCATED AT 250 WORDS)