Study Population
Subjects in this study included pediatric patients recruited from
outpatient clinics in the Stockholm area as previously described26. Consent was obtained from parents of each study
subject. Briefly, children ages 10 to 18 years were recruited and
sensitization to dog dander was confirmed by either positive skin prick
test response (wheal size > 3 mm), serum IgE to dog dander
> 0.10 kUA/L, or both. Allergen-sensitized
subjects were included regardless of a history of clinical allergy
symptoms to dog dander. Subjects with impaired lung function due to any
cause other than asthma and any completed or current allergen-specific
immunotherapy to furry animals were excluded from the study. Sixty (60)
allergen-sensitized children were included in the study group, and a
further 17 non-sensitized children without current symptoms of airway
allergy were included in the control group. All subjects underwent
venous blood sampling for preparation of serum, clinical history and
physical examination, dynamic spirometry, and methacholine
bronchoprovocation. Clinical characteristics are summarized in Table 1.