Respiratory Tract Dysbiosis Is Associated with Worse Outcomes in Mechanically Ventilated Patients

Biological subphenotypes of acute respiratory distress syndrome may not reflect differences in alveolar inflammation

“…(Dickson et al, 2020;Panzer et al, 2018). Previous studies showed that the lung microbiome composition of critically ill patients is not only a predictor for ARDS development and ICU-outcome, but is also associated with alveolar and systemic inflammation (Dickson et al, 2016(Dickson et al, , 2020Kitsios et al, 2020;Panzer et al, 2018). Panzer et al found that the lung microbial composition at admission was related to plasma intercellular adhesion molecule-1, vascular endothelial growth factor, and IL-8 and that the variation 48 h after hospitalization was associated with IL-6 and IL-8.…”

“…However, systemic inflammation is not specific for ARDS and it is unknown whether these subphenotypes also reflect differences in the alveolar compartment (Zador et al, 2020). Alveolar inflammation and dysbiosis of the lung microbiome have shown to be important mediators in the development of lung injury (Dickson et al, 2020;Kitsios et al, 2020;Thompson et al, 2017). Specifically, the presence of Enterobacteriaceae in the lung was predictive for both poor ICU-outcome and the clinical diagnosis of ARDS (Dickson et al, 2020).…”

Plasma microbial cell-free DNA load is associated with mortality in patients with COVID-19

“…We enrolled 15 critically-ill patients with COVID-19 (confirmed by nasopharyngeal qPCR for SARS-CoV-2) in a prospective ICU cohort study [ 3 ]. Following informed consent, we obtained plasma samples for conducting mcfDNA-Seq with the Karius Test (Karius, Inc. Redwood City, CA)[ 4 ].…”

Microbial signatures in the lower airways of mechanically ventilated COVID19 patients associated with poor clinical outcome

“…Recent studies have used this approach to uncover microbial signatures in patients with ARDS. 15,16 Increased bacterial burden and the presence of gut-associated bacteria in the lung were shown to worsen outcomes in these critically ill patients 15,17 , highlighting the potential role of the lung microbiome in predicting outcomes in ARDS. In a recent study using whole genome sequencing to pro le the gut microbiome of 69 patients from Hong Kong, investigators identi ed an increased abundance of opportunistic fungal pathogens among patients with con rmed COVID-19 18 .…”