Background: Invasive Fungal Infections (IFI) are emergent complications of COVID-19. In this study, we aim to describe the prevalence, related factors, and outcomes of IFI in critical COVID-19 patients. Methods: We conducted a nested case–control study of all COVID-19 patients in the intensive care unit (ICU) who developed any IFI and matched age and sex controls for comparison (1:1) to evaluate IFI-related factors. Descriptive and comparative analyses were made, and the risk factors for IFI were compared versus controls. Results: We found an overall IFI prevalence of 9.3% in COVID-19 patients in the ICU, 5.6% in COVID-19-associated pulmonary aspergillosis (CAPA), and 2.5% in invasive candidiasis (IC). IFI patients had higher SOFA scores, increased frequency of vasopressor use, myocardial injury, and more empirical antibiotic use. CAPA was classified as possible in 68% and 32% as probable by ECMM/ISHAM consensus criteria, and 57.5% of mortality was found. Candidemia was more frequent for C. parapsilosis Fluconazole resistant outbreak early in the pandemic, with a mortality of 28%. Factors related to IFI in multivariable analysis were SOFA score > 2 (aOR 5.1, 95% CI 1.5–16.8, p = 0.007) and empiric antibiotics for COVID-19 (aOR 30, 95% CI 10.2–87.6, p = <0.01). Conclusions: We found a 9.3% prevalence of IFIs in critically ill patients with COVID-19 in a single center in Mexico; factors related to IFI were associated with higher SOFA scores and empiric antibiotic use for COVID-19. CAPA is the most frequent type of IFI. We did not find a mortality difference.

Among critically ill patients, COVID-19-associated pulmonary aspergillosis (CAPA) is a challenging complication. The recommended diagnostic methods for this disease are bronchoalveolar lavage (BAL) culture and galactomannan (GM) testing, which were not widely available during the pandemic. There is scarce information regarding GM testing in other respiratory specimens. Our objective was to compare the agreement of GM between BAL and tracheal aspirate (TA) samples. We selected patients with COVID-19 and those with suspected CAPA who were admitted in the intensive care unit (ICU). GM was routinely done in BAL. We performed GM in TA samples and compared the results. The agreement was evaluated with Cohen's Kappa coefficient. GM was considered positive when an OD index ≥ 1 in BAL and ≥ 2 in TA were found. Probable CAPA was considered when the ECMM/ISHAM criteria were met. A descriptive analysis of clinical characteristics and mortality was made. We included 20 patients with suspected CAPA from 54 patients with critical COVID-19, of which 5 (9%) met the probable category. Aspergillus fumigatus was the most frequent isolate. We found moderate agreement between BAL and TA GM (Kappa = 0.47, p = 0.01, 95% CI.04–0.9), whereas TA GM had 75% sensitivity (95% CI 19.4–99.4%), 81.2% specificity (95% CI 54.4–95.9%), 50% positive predictive value (95% CI 23.8–76.3%),] and 92.8% negative predictive value (95% CI 70.1–98.6%), and 80% accuracy (95% CI 56.3–94.3%). Lastly, three (60%) patients with CAPA died during hospitalization compared to 40% (6/15) without CAPA (p = 0.4). In conclusion, a moderate agreement between TA GM and BAL was found. Therefore, TA testing may aid in ruling out CAPA due to high negative predictive value when bronchoscopies are unavailable.