Prevalence of IgE sensitization to dog allergen components and the association with clinical outcomes in a cohort of young asthmatics

<bold>Introduction:</bold> Allergies to furry animals are a major concern since prevalence rates have increased. Little is known about the effect of sensitization to different dog-allergen components on asthma outcomes. We investigated the prevalence of IgE antibodies to dog-allergen components and the association with clinical outcomes in young asthmatics sensitized to dogs. <bold>Methods:</bold> From the MIDAS cohort, 283 subjects with asthma (age 10-35) and specific IgE (sIgE) to dog dander were analyzed for sensitization to the dog lipocalins (Can f 1, Can f 2, Can f 4, Can f 6),serum albumin (Can f 3) and prostatic kallikrein (Can f 5) (0.1≥ kU_A/L, ImmunoCAP). Independent asscociations between sIgE and the clinical outcomes lung function (FEV₁), Asthma Control Test (ACT),metacholine airway responsiveness (PD₂₀) and recent asthma attacks were assessed by performing multivariate logistic regression analyses. <bold>Results:</bold> Sensitization to at least one dog lipocalin was most common (67%),whereas Can f 3 sensitization was less frequent (20%). In multivariate analyses adjusted for age, gender, weight, height, ongoing medication, smoking and dog ownership, IgE to Can f 3 associated with ACT<20 (OR 1.73;p=0.028) and with FEV₁<80%(trend;p=0.069), but not with PD₂₀ or recent asthma attacks. IgE to dog dander and to other dog-allergen components were not significantly associated with clinical outcomes (p=0.53-0.96). <bold>Conclusion:</bold> Despite the low prevalence, levels of IgE to Can f 3 but not to dog dander, dog lipocalins or Can f 5, were associated with clinical outcomes in young asthmatics. Measurement of sIgE to minor dog-allergen components and its clinical application needs further exploration.