Diagnostic value of the IMMY Aspergillus LFA on bronchoalveolar lavage fluid of intensive care patients

Albert Dunbar 1, Toine Mercier *2, Vincent Veldhuizen 1, Bart Rijnders 1

Author address: 

1 Erasmus Medical Center, Rotterdam, Netherlands; 2 Universitair Ziekenhuis Leuven, Leuven, Belgium

Abstract: 

Background: The diagnosis of invasive pulmonary aspergillosis(IPA) is challenging, especially in the intensive care unit(ICU) setting, where clinical symptoms as well as imaging are mostly aspecific. Recently, Aspergillus lateral flow tests were developed to decrease the time to diagnosis of IPA. Several studies evaluated the value of these new tests in the hematology population. We aimed to evaluate the value of a new lateral flow test for Aspergillus in ICU patients.

Materials/methods: Using left-over bronchoalveolar lavage fluid (BALf) from patients previously admitted to the ICU of a university hospital, we studied the performance of the sōna Aspergillus galactomannan lateral flow assay (LFA, IMMY, Norman, Oklahoma, USA). Patients included were >18 years of which BALf stored at ≤-20°C was available. The Platelia™ Aspergillus EIA test was used to measure galactomannan. Based on the result of the fungal culture and galactomannan, the patients were classified according to 2 frequently used definitions: the EORTC-MSG criteria and the modified AspICU criteria (=AspICU criteria in which galactomannan is incorporated as well). For each case of IPA, we aimed to include 2 aspergillus negative controls. BALf was tested with the LFA according to the manufacturer’s instruction. The LFA was read out visually and with a digital reader by researchers blinded to the clinical diagnosis and IPA classification.

Results: Seventy-two patients were included of which 14 had probable or proven IPA according to the EORTC/MSG definitions, 24 had IPA according to the modified AspICU criteria and 48 served as IPA negative controls. Depending on the definitions used, sensitivities and specificities varied between 0.79 and 0.86 (table 1). The area under the ROC curve of the LFA was 0.85.

Conclusions: In ICU patients, the IMMY LFA performed well on BALf and can be used as a rapid screening test while waiting for culture results and conventional galactomannan results.

Presenter email address: [email protected]

2020

abstract No: 

6119

Full conference title: 

European Congress of Clinical Microbiology and Infectious Diseases 2020
    • ECCMID 30th (2020)