Other secondary indicators
allergy, Peripheral venous blood
SECONDARY, ALLERGY
Other secondary outcomes were changes in circulating immunoglobulin level (serum dust mite-specific IgE) at baseline, 24 month and 36 month. Peripheral venous blood was taken and was separated by centrifugation at room temperature for 7 minutes at 3500 r/min, and then was stored at -80°C pending analysis. Serum Derp and Derf-specific IgE was detected using Thermo phadia 250 automatic fluorescence immunoassay analyzer and ImmunoCAP Specific IgE enzyme-labeled secondary antibody kit. Allergen criteria for detection were Derp and Derf positive with other allergens negative. The test results were graded from 0 to 6 according to Derp and Derf-specific IgE concentration. Grade 0 was defined as sIgE < 0.35 kU/L; Grade 1 was defined as sIgE ≥ 0.35 kU/L; Grade 2 was defined as sIgE ≥ 0.70 kU/L; Grade 3 was defined as sIgE ≥ 3.5 kU/L; Grade 4 was defined as sIgE ≥ 17.5 kU/L;Grade 5 was defined as sIgE ≥ 50 kU/L; Grade 6 was defined as sIgE ≥ 100 kU/L.Besides, Grade 0 indicated allergy (-) while Grade 1-6 indicated varying degrees of allergy,and Grade 1 and above was considered positive for sIgE.