Comparison between ImmunoCAP and multiple antigen simultaneous tests for measuring Aspergillus-specific Immunoglobulin E levels in Aspergillus-sensitized patients

Abstract

Objectives: Aspergillus sensitization is important for patients with asthma. In Japan, the methods applied to measure allergen-specific immunoglobulin E (IgE) levels in blood are the single antigen test, ImmunoCAP (IC), and multiple antigen simultaneous tests, View Allergy® (VA) or MAST IV® (MA). Here, we report the concordance rates (CR) for Aspergillus-specific IgE levels between IC and VA or MA. Methods: Aspergillus-specific IgE levels in serum samples from 34 male and 23 female patients with bronchial asthma were measured by ImmunoCAP, View Allergy® (both Thermo Fisher Scientific, Uppsala, Sweden) and MAST IV® (Hitachi Chemical Diagnostics, Inc. Mountain View, CA, USA). Results of Class 1 or greater were regarded as positive, and the CRs between the methods were assessed. Results: Of the 57 patients, 24 were found to be positive for Aspergillus-specific IgE by IC, and 5 had allergic bronchopulmonary aspergillosis (ABPA). Significant intraclass correlations were observed between IC and VA (r=0.964, p<0.001) and between IC and MA (r=0.620, p<0.001). Between IC and VA, the CR, positive concordance ratio, and negative concordance ratio was 98.2%, 100%, and 96.9%, respectively; between IC and MA, these values were 77.2%, 45.8%, and 100%, respectively. All five patients with ABPA were found to be positive for Aspergillus-specific IgE by VA, whereas only three of these patients (60%) were found to be positive by MA. Conclusions: In patients with asthma, measurements obtained by IC were more concordant with those obtained by VA compared with those obtained by MA.

Keywords

• asthma
• immunocap
• aspergillus