Combination of Mycological Criteria: a Better Surrogate to Identify COVID-19-Associated Pulmonary Aspergillosis Patients and Evaluate Prognosis?

J Clin Microbiol. 2022 Mar 16;60(3):e0216921. doi: 10.1128/JCM.02169-21. Epub 2022 Jan 5.

Abstract

Diagnosis of coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) remains unclear especially in nonimmunocompromised patients. The aim of this study was to evaluate seven mycological criteria and their combination in a large homogenous cohort of patients. All successive patients (n = 176) hospitalized for COVID-19 requiring mechanical ventilation and who clinically worsened despite appropriate standard of care were included over a 1-year period. Direct examination, culture, Aspergillus quantitative PCR (Af-qPCR), and galactomannan testing were performed on all respiratory samples (n = 350). Serum galactomannan, β-d-glucan, and plasma Af-qPCR were also assessed. The criteria were analyzed alone or in combination in relation to mortality rate. Mortality was significantly different in patients with 0, ≤2, and ≥3 positive criteria (log rank test, P = 0.04) with death rate of 43.1, 58.1, and 76.4%, respectively. Direct examination, plasma qPCR, and serum galactomannan were associated with a 100% mortality rate. Bronchoalveolar lavage (BAL) galactomannan and positive respiratory sample culture were often found as isolated markers (28.1 and 34.1%) and poorly repeatable when a second sample was obtained. Aspergillus DNA was detected in 13.1% of samples (46 of 350) with significantly lower quantitative cycle (Cq) when associated with at least one other criterion (30.2 versus 35.8) (P < 0.001). A combination of markers and/or blood biomarkers and/or direct respiratory sample examination seems more likely to identify patients with CAPA. Af-qPCR may help identifying false-positive results of BAL galactomannan testing and culture on respiratory samples while quantifying fungal burden accurately.

Keywords: Aspergillus; COVID-19; COVID-19-associated pulmonary aspergillosis; critical care; diagnosis.

MeSH terms

  • Bronchoalveolar Lavage Fluid / microbiology
  • COVID-19* / complications
  • COVID-19* / diagnosis
  • Humans
  • Invasive Pulmonary Aspergillosis* / complications
  • Mannans / analysis
  • Prognosis
  • Pulmonary Aspergillosis*
  • Sensitivity and Specificity

Substances

  • Mannans