Accuracy of galactomannan testing on tracheal aspirates in COVID-19-associated pulmonary aspergillosis

Mycoses. 2021 Apr;64(4):364-371. doi: 10.1111/myc.13216. Epub 2021 Feb 13.

Abstract

Objective: Our aim was to evaluate the performance of two galactomannan (GM) assays (Platelia Aspergillus EIA, Bio-Rad® , and Aspergillus GM LFA, IMMY® ) in tracheal aspirate (TA) samples of consecutive critically ill patients with COVID-19.

Methods: We included critically ill patients, performed GM-EIA and GM-Lateral Flow Assay (GM-LFA) in TA and followed them until development of COVID-19-associated pulmonary aspergillosis (CAPA) or alternate diagnosis. CAPA was defined according to the modified AspICU criteria in patients with SARS-CoV-2 infection. We estimated sensitivity, specificity, positive and negative predictive values for GM-EIA, GM-LFA, the combination of both or either positive results for GM-EIA and GM-LFA. We explored accuracy using different breakpoints, through ROC analysis and Youden index to identify the optimal cut-offs. We described antifungal treatment and 30-day mortality.

Results: We identified 14/144 (9.7%) patients with CAPA, mean age was 50.35 (SD 11.9), the median time from admission to CAPA was 8 days; 28.5% received tocilizumab and 30-day mortality was 57%. ROC analysis and Youden index identified 2.0 OD as the best cut-off, resulting in sensitivity and specificity of 57.1% and 81.5% for GM-EIA and 60% and 72.6% for GM-LFA, respectively.

Conclusions: The diagnostic performance of GM in tracheal aspirates improved after using a cut-off of 2 OD. Although bronchoalveolar lavage testing is the ideal test, centres with limited access to bronchoscopy may consider this approach to identify or rule out CAPA.

Keywords: COVID-19; SARS-CoV-2 infection; galactomannan; invasive aspergillosis.

Publication types

  • Evaluation Study

MeSH terms

  • Adult
  • Antifungal Agents / therapeutic use
  • COVID-19 / complications*
  • Diabetes Complications / complications
  • Female
  • Humans
  • Male
  • Mannans / analysis*
  • Middle Aged
  • Obesity / complications
  • Pulmonary Aspergillosis / diagnosis*
  • Pulmonary Aspergillosis / drug therapy
  • Pulmonary Aspergillosis / etiology
  • Pulmonary Aspergillosis / mortality
  • Sensitivity and Specificity
  • Trachea / chemistry*
  • Trachea / microbiology

Substances

  • Antifungal Agents
  • Mannans
  • galactomannan