Allergen-Specific IgE Measurement: Intermethod Comparison of Two Assay Systems in Diagnosing Clinical Allergy

Our aim was to examine the performance of IMMULITE 2000 assay for specific IgE (sIgE) by comparing it with ImmunoCAP technology in light of a clinical background.

Measurements of sIgE were done in a selected patient group (N = 569; varied sample size for each allergen) and in a random sample group (N = 100; 8 allergens). sIgE results were correlated with skin-prick test results (selected patients) and medical history (nonselected patients).

We have detected fair to excellent correlation and agreement between the results of both assays, despite their methodological differences, both in selected and nonselected patient group (ρc = 0.431-0.976; ρc = 0.390-0.972, respectively). Associations of sIgE levels with skin-prick test (SPT) levels and medical history have shown significant correlation for both assays for majority of tested allergens, where applicable (D. pteronyssinus, cat dander, egg white, milk, peanut, orchard grass, Alternaria tenuis, and common ragweed in selected patients; birch, cat dander, common ragweed, D. pteronyssinus, and orchard grass in nonselected; P < 0.05 for all).

Laboratory testing for sIgE can be successfully accomplished by IMMULITE 2000 immunoanalyzer at a diagnostic accuracy relative to SPT, comparable to the results acquired by CAP technology but not fully comparable on the level of an individual patient.