Impact of Aspergillus PCR on the Management of Invasive Aspergillosis: A Tertiary-care Hospital Experience during the COVID-19 Pandemic

Abstract

In this study, we investigated whether Aspergillus polymerase chain reaction (PCR) test had any effect on the management of invasive aspergillosis (IA) in routine patient management, retrospectively. A total of 293 Aspergillus PCR tests were performed in 235 patients between November 2020 and April 2022. One hundred and eighty-nine (80.4%) patients were hospitalized in the intensive care unit, and 142 (60.4%) were positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on the day of Aspergillus PCR request. Only 21 (7.2%) samples were bronchoalveolar lavage (BAL) fluid; the remaining were non-bronchoscopic lavage (NBL) fluid (n = 156, 53.2%), and sputum (n = 116, 39.6%). Aspergillus PCR was positive in 35 (11.9%) samples. Twenty-six patients were diagnosed with IA (1 proven, 6 probable, 19 possible) according to the EORTC/MSG criteria, and nine SARS-CoV-2 infected patients with no host factor were diagnosed with coronavirus disease 2019 (COVID-19) associated pulmonary aspergillosis (8 probable, 1 possible) according to ECMM/ISHAM criteria when PCR testing was excluded. Although positive PCR result did not change the IA diagnostic category of any patient, substantial agreement was found between galactomannoprotein antigen and PCR tests in BAL fluid (87.5%) and moderate agreement in NBL fluid (81.8%), with Cohen's kappa values of 0.714 and 0.506, respectively (p < 0.05 for both). A total of 22 patients (62.9%) who met at least probable or possible IA criteria received antifungal treatment, whereas 32 patients who received antifungal treatment did not meet any of the consensus criteria for IA; 9 of them received treatment with a positive Aspergillus PCR result. In conclusion, we observed a limited impact of Aspergillus PCR on treatment decisions for IA in a period when bronchoscopy was avoided due to COVID-19 and PCR results were not readily available for a cost-effective and appropriate use of Aspergillus PCR, it might be beneficial to establish an institutional diagnostic algorithm.