Comparison of six Aspergillus-specific IgG assays for the diagnosis of chronic pulmonary aspergillosis (CPA).
J Infect. 2015 Dec 8;
Authors: Page ID, Richardson MD, Denning DW
OBJECTIVES: Chronic pulmonary aspergillosis (CPA) is estimated to affect 3 million persons worldwide. Aspergillus-specific IgG is a key component in CPA diagnosis. We aimed to establish the optimal diagnostic cut offs for CPA and the comparative performance of six assays in this context.
METHODS: Sera from 241 patients with CPA and 100 healthy blood donors were tested using five Aspergillus-specific IgG assays plus precipitin testing using Microgen Aspergillus antigens.
RESULTS: Receiver operating characteristic (ROC) curve area under the curve (AUC) results were as follows; ThermoFisher Scientific ImmunoCAP 0.996 (95% confidence interval 0.992 - 1), Siemens Immulite 0.991 (0.982-1), Serion 0.973 (0.960 - 0.987), Dynamiker 0.918 (0.89 - 0.946) and Genesis 0.902 (0.871 - 0.933). Optimal CPA diagnostic cut-offs were; ImmunoCAP 20 mg/L (96% sensitivity, 98% specificity), Immulite 10 mg/L (96% sensitivity, 98% specificity), Serion 35 U/ml (90% sensitivity, 98% specificity), Dynamiker 65 AU/ml (77% sensitivity, 97% specificity) and Genesis 20 U/ml (75% sensitivity, 99% specificity). The precipitin test was 59% sensitive and 100% specific.
CONCLUSIONS: ImmunoCAP and Immulite were statistically significantly superior to the other assays. Precipitins testing performed poorly. The currently accepted ImmunoCAP cut-off of 40 mg/L appears sub-optimal for CPA diagnosis and may require revision in this context.
PMID: 26680697 [PubMed - as supplied by publisher]