Pre-treatment allergen-specific IgE analysis and outcomes of allergen immunotherapy

¹Department of Otolaryngology, Örebro University Hospital, Örebro, Sweden
²Department of Laboratory Medicine, Örebro University Hospital, Örebro, Sweden
³School of Medical Sciences, Örebro University, Örebro, Sweden
⁴Department Clinical Immunology and Transfusion Medicine, School of Medicine and Health, Örebro University, Örebro, Sweden

Summary 
Background. Patients show varied results to allergen immunotherapy (AIT. The reason for this variability is unclear. Objective. To describe the relationship between AIT efficacy and demographic characteristics, as well as pre-treatment plasma levels of specific IgE-antibodies to grass and birch pollen. Methods. A retrospective study was performed based on medical records of 128 patients who received AIT. The patients completed a questionnaire and pre-AIT plasma levels of allergen-specific IgE to grass and birch pollen were measured using EUROLINE DPA-Dx pollen 1 method. Results. Seventy percent of patients classified their allergic symptoms as less severe after AIT. Twenty-seven percent had received AIT targeting only grass pollen, 19% targeting only birch pollen, and 55% targeting both grass and birch. A total of 35 different IgE profiles were found across our study population. On comparison of the demographic characteristics and concentration of allergen-specific IgE-antibodies, no statistically significant differences could be found. Conclusions. The majority of patients rated their allergic symptoms as less severe after AIT. No clear relationship could be demonstrated between pre-treatment allergen-specific IgE concentration, or demographic characteristics, and effect of AIT. There may be other factors underlying the different responses to AIT.