Severe childhood asthma and allergy to furry animals: refined assessment using molecular-based allergy diagnostics.
BACKGROUND
Allergy to cats and dogs and polysensitization towards these animals are associated with severe childhood asthma. Molecular-based allergy diagnostics offers new opportunities for improved characterization and has been suggested to be particularly useful in patients with polysensitization and/or severe asthma. The aim was to use extract- and molecular-based allergy diagnostics to compare patterns of IgE sensitization towards aeroallergens in children with problematic severe and controlled asthma.


METHODS
Children with a positive ImmunoCAP towards any furry animal (cat, dog or horse) were recruited from a Nationwide Swedish study on severe childhood asthma. Severe (n = 37, age 13 years) and controlled (n = 28, age 14 years) asthmatics underwent assessment of allergic sensitization by ImmunoCap (kUA /l) and immunosolid-phase allergen chip (ISAC). In addition, Asthma Control Test, spirometry and a methacholine challenge were performed.


RESULTS
Children with severe asthma had lower asthma control (p < 0.001) and FEV1 (p = 0.001) and more bronchial hyper-responsiveness (p = 0.008) in spite of high doses of inhaled steroids (≥800 μg budesonide). Children with severe asthma displayed higher levels of IgE antibodies towards cat (17 vs. 3.9, p = 0.027), dog (3.8 vs. 1.2, p = 0.012) and horse (7.4 vs. 0.7, p = 0.014). Sensitization towards Can f 2 (22% vs. 0%, p = 0.009) and Equ c 1 (51% vs. 25%, p = 0.03) was more common in severe asthma. IgE levels towards Equ c 1 correlated with asthma control (r = -0.41, p = 0.04).


CONCLUSIONS
Children with severe allergic asthma had higher sIgE levels to cat, dog and horse. Molecular-based allergy diagnostics revealed a more complex molecular spreading of allergen components in children with the most severe disease.
Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden; Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden; Centre for Allergy Research, Karolinska Institutet, Stockholm, Sweden.
Jon R
JR
Konradsen
Björn
B
Nordlund
Annica
A
Onell
Magnus P
MP
Borres
Hans
H
Grönlund
Gunilla
G
Hedlin
D000293:Adolescent; D000367:Age Factors; D000485:Allergens; D000818:Animals; D001249:Asthma / Q000097:blood / Q000175:diagnosis* / Q000276:immunology / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D002415:Cats; D002648:Child; D003430:Cross-Sectional Studies; D004285:Dogs; D005260:Female; D006197:Hair / Q000276:immunology*; D006736:Horses; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D007159:Immunologic Tests; D008168:Lung / Q000503:physiopathology; D008297:Male; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D057805:Pets / Q000276:immunology*; D011058:Pollen / Q000276:immunology*; D011237:Predictive Value of Tests; D012720:Severity of Illness Index
D000485:Allergens; D015415:Biomarkers; D007073:Immunoglobulin E
allergy; children; furry animals; molecular-based allergy diagnostics; severe asthma