Allergen-specific IgE detection
All patient serum sIgE samples were collected and tested by a certified
third-party laboratory service provider, KingMed Diagnostics, with
uniform and standardized procedures.
A full-automated in vitro allergen detector, the ImmunoCAP 1000 system
(Thermo Fisher Scientific Inc., California, USA), was used to detect
allergen-specific sIgE in the sera, as described elsewhere9, 11. The sIgE levels for nine categories of
allergens (ImmunoCAP number, species source) were evaluated in this
study, including those for the house dust mite (d1: house dust mite;Dermatophagoides pteronyssinus ), German cockroach (i6;Blatella germanica ), tree pollen mix (tx4: Quercus alba ,Ulmus americana , Platanus acerifolia , Salix caprea ,Populus deltoides ), mold mix (mx1: Penicillium
chrysogenum , Cladosporium herbarum , Aspergillus
fumigatus , Alternaria alternata ), dog dander (e5), egg whites
(f1), cow’s milk (f2), crab (f23), and shrimp (f24). Positive reactivity
was defined as an sIgE level ≥ 0.35 kUA/L (class 1 or above). According
to the absolute sIgE levels, the reactivity was categorized
quantitatively into six classes: class 1 (≥ 0.35 to < 0.70
kUA/L), class 2 (≥ 0.70 to
<3.50 kUA/L), class 3 (≥
3.50 to < 17.50 kUA/L), class 4 (≥ 17.50 to < 50.00
kUA/L), class 5 (≥ 50.00 to < 100.00 kUA/L), and class 6 (≥
100.00 kUA/L) 9, 11.