Recent research suggests that examining the components of a patient’s feces could provide critical insights into their proximity to death. A study led by Alexander de Porto at the University of Chicago and the University of Amsterdam has introduced a new index for medical diagnostics: the metabolic dysbiosis score (MDS). This score aims to assess mortality risk for critically ill patients in intensive care over a 30-day period.
While the findings are promising, the researchers emphasize that further validation is needed before MDS can be adopted widely in clinical practice. “The findings suggest that fecal metabolic dysbiosis, quantified through the MDS, holds potential as a biomarker to identify critically ill patients at increased risk of mortality,” de Porto and colleagues, Eric Pamer and Bhakti Patel, told ScienceAlert. They noted that this research highlights the significance of gut-derived metabolites as vital contributors to patient resilience, paving the way for advancements in precision medicine.
Patients in intensive care often suffer from conditions like sepsis and acute respiratory distress, with their symptoms presenting differently despite diagnoses of the same syndrome. This variability complicates treatment; patients may respond in unique ways to identical interventions. The researchers propose that pinpointing specific traits for treatment, rather than addressing the entire syndrome, might improve outcomes. Previous studies indicate that critically ill patients tend to show diminished gut microbiota diversity and altered metabolite levels.
To explore these factors, De Porto and his team investigated dysbiosis—an imbalance in gut microbiome—among critically ill patients. They analyzed fecal samples from 196 individuals experiencing respiratory failure or shock, dividing them into a training group of 147 and a validation group of 49. Using concentrations of 13 specific fecal metabolites, they developed the MDS, yielding promising results for further research.
“The MDS performed well in predicting mortality in the training cohort of medical ICU patients, with 84 percent accuracy, 89 percent sensitivity, and 71 percent specificity,” the researchers reported. However, the validation group’s results, while indicative of similar trends, did not achieve statistical significance due to its smaller size. This highlights both the potential of the MDS and the need for further validation in larger groups before it can be implemented broadly.
Interestingly, the study found no direct correlation between lower microbiome diversity and poor outcomes, contrasting with previous research. Instead, the results indicated that dysbiosis is significantly linked to heightened mortality risk, emphasizing its importance in patient health.
Despite the need for more refinement in their approach—especially given the inconclusive results from the validation cohort—the researchers found encouraging signs. Their lab has previously demonstrated that fecal metabolites can help identify liver transplant patients at greater risk of post-operative infections. Although specific treatments related to MDS have yet to be determined, the findings suggest several potential pathways for future research.
“The metabolites comprising the score, such as short-chain fatty acids, bile acids, and tryptophan metabolites, point to biological pathways that might be targeted therapeutically,” the researchers explained. Possible interventions could include dietary adjustments, probiotic administration, or direct supplementation with these metabolites.
The next steps involve further validation of the MDS with new patient groups and exploring whether the identified dysbiosis is a causal factor or merely a symptom of other issues. “Subsequently,” the researchers concluded, “intervention trials targeting specific metabolites or metabolic pathways are necessary to assess therapeutic benefits.” This groundbreaking research has been published in Science Advances.