Immediate adverse reactions to immunotherapy

Abstract

Background: Immunotherapy, which has been used since the beginning of this century, has potential adverse reactions. The purpose of this study was to evaluate immediate local and systemic reactions to allergen immunotherapy and to compare rates of adverse reactions to aluminum-adsorbed versus calcium-adsorbed allergen vaccines.

Methods: 108 cases (38 girls and 70 boys) were given allergen immunotherapy between 1997 and 2001. The following data were recorded for each patient: primary disease being treated (allergic rhinitis, asthma, or allergic rhinitis and asthma), allergic sensitivities (dust mite or grass pollen), number of injections, the stage of immunotherapy (buildup or maintenance), dilution of allergen vaccine, and type of allergen vaccine (calcium- or aluminum-adsorbed). Adverse reactions were classified as systemic or local. Local reactions were classified as hyperemia and induration less than 5 cm, more than 5 cm, itching, and pain.

Results: 4783 injections were evaluated in 108 subjects with allergic rhinitis (44%), asthma (40%), allergic asthma, and rhinitis (16%). Frequency of immediate systemic reaction was 0.13%. Frequency of immediate local reactions were: hyperemia and induration less than 5 cm 3%, greater than 5 cm 0.16%, local itching 0.15%, and local pain 0.2%. There was no significant difference in systemic and local reactions between calcium- and aluminum-adsorbed vaccines. Immediate local reactions were more frequent during maintenance therapy compared to buildup. Subjects were more likely to have local reactions during maintenance therapy if they had allergic rhinitis (p < 0.05) or were receiving grass pollen vaccine (p < 0.01).

Conclusion: Immediate adverse reactions were uncommon when given to children with asthma and allergic rhinitis. Aluminium- and calcium-adsorbed allergen vaccines showed similar rates of systemic and local reactions.