P424 Comparative analysis of Galactomannan Lateral Flow Assay, Galactomannan Enzyme Immunoassay and BAL culture for diagnosis of COVID-19-associated pulmonary aspergillosis

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM ObjectivesInvasive pulmonary aspergillosis is a well-known complication in COVID-19 patients. A reliable and early diagnosis is essential for the early initiation of antifungal therapy. On the other hand, conventional Bronchoalveolar lavage (BAL) culture may lack the specificity of differentiating between colonization and infection. Here, we aimed a comparative analysis of Galactomannan Lateral Flow Assay (GM-LFA), Galactomannan Enzyme Immunoassay (GM-EIA), and BAL culture for diagnosis of COVID-19-associated pulmonary aspergillosis (CAPA).MethodsBAL (n = 105) and serum samples (n = 101) from COVID-19 patients who were mechanically ventilated for ≥4 days in intensive care units (ICUs) were evaluated by GM-LFA and GM-EIA. All BAL samples were cultured on Sabouraud-Chloramphenicol dextrose Agar. Diagnostic performance of GM-LFA and GM-EIA in BAL (GM indexes ≥1) and serum (GM indexes >0.5) were evaluated and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) and Roc curve compared with BAL culture calculated.ResultsThe Aspergillus GM-LFA for serum and BAL samples showed a sensitivity of 46.9% and 54.5%, specificity of 100% and 91.7%, PPV of 100% and 75%, and NPV of 80.2% and 81.5%, when compared with BAL culture, respectively. GM-EIA showed sensitivities of 56.3% and 60.6%, specificities of 94.2% and 88.9%, PPVs of 81.8% and 71.4%, and NPVs of 82.3% and 83.1% for serum and BAL samples, respectively.ConclusionAccording to our results BAL GM detection using both EIA and LFA may be a promising approach for early diagnosis of CAPA and differentiating between colonization and invasive infection.