Assessment of Platelia Aspergillus enzyme immunoassay for the diagnosis of invasive aspergillosis

Abstract

Background and purpose: This study investigated the diagnostic value of Platelia Aspergillus enzyme immunoassay (EIA) for galactomannan (GM) antigen in patients at risk of invasive aspergillosis (IA), and its association with clinical course and outcome.

Methods: A total of 304 blood samples were collected from 189 patients at risk of IA during a 1-year period at a tertiary referral center. Classification of IA was made on the basis of the European Organization for Research and Treatment of Cancer case definitions.

Results: Of the 189 patients, 5 had proven IA, 9 had probable IA, 26 had possible IA, and 149 had no IA. Diagnostic levels of GM were detected in 80% of proven and in 77% of probable IA cases. The overall sensitivity, specificity, and positive and negative predictive values for this assay, using a 1.5 index cut-off value, were 78.6%, 93.9%, 55.0%, and 97.9%, respectively. With the 0.5 index cut-off value, the sensitivity would increase to 100%. A close relationship was found between clinical course and the kinetics of GM indices in survivors.

Conclusions: The Platelia Aspergillus EIA is a useful screening test for the detection of IA. Regular monitoring of the kinetics of GM-EIA indices is a useful predictor of clinical course and outcome.