Using Microbiomes to Diagnose Ventilator-Associated Pneumonia
Georgios Kitsios, MD, PhD, discusses his team's interim results an analysis that is providing insights into the microbiome dynamics of critically ill patients with VAP.
Ventilator-associated pneumonia (VAP) has become a more modern clinical issue since the COVID-19 pandemic. Many patients with a severe form of the virus require mechanical ventilation, which is associated with essentially a 50% increased risk of developing VAP while under care.
Though the condition can be diagnosed with standard microbiological techniques, clinicians lack optimal interpretation of ventilated patients’ risk of progressing to VAP. There is a dearth of understanding of how the microbiome interacts with an intubated respiratory track leading to the condition, for example, and patients may be exposed to broad-spectrum antibiotics in their care.
To address this issue, Georgios Kitsios, MD, PhD, assistant professor of medicine in the division of pulmonary, allergy, critical care and sleep medicine at the University of Pittsburgh, and colleagues have been conducting research into the microbiome interaction with respiratory infections like VAP—and whether there are opportunities to identify more timely and efficient means of intervening on a patient based on new biomarkers.
In an interview featured in the first issue of The Respiratory Report, a quarterly pulmonology research newsletter powered by the American Lung Association Research Foundation, Kitsios discussed his team’s work in the ongoing LUCID-IMHO study and how it may contribute to developing microbiome-based diagnostics for VAP.
Key among the findings from the 2-part study thus far include identifying a progressive dysbiosis in oral, lung, and gut microbial communities among patients who are mechanically ventilated—with the lung microbiome being the greatest predictor of clinical outcomes in patients, Kitsisos explained. The team additionally found that a receipt of anaerobic spectrum antibiotics was linked to depleted anaerobic bacteria from the respiratory and gut microbiome, which also correlated with poorer outcomes.
“And finally, we derived a dysbiosis index by which patients with low microbial diversity and high pathogen abundance in the respiratory communities had worse clinical outcome—a finding we validated in COVID-19, and even after adjustment for very well-known predictors of adverse outcome on the ventilator, really highlighting independent effects of microbiota,” Kitsios said. “We consider these findings particularly promising for improving diagnosis of ventilator-associated pneumonia, prognostication of acute respiratory failure, as well as defining patient subpopulations and specific targets for microbiome based interventions in the ICU.”
To learn more about Kitsios’ research, read his contribution to the first issue of The Respiratory Report here:
