Researchers from the University of Oxford have explored how drug‑resistant strains of Pseudomonas aeruginosa might move from the gut to the lungs. The findings, now published in Nature Communications, shed light on a possible pathway by which these stubborn bacteria can spread within the human body, raising important questions about prevention and treatment for patients at high risk of respiratory infections. The study builds on a growing body of work that links gut microbiota to pulmonary health, suggesting that the intestinal reservoir could play a role in subsequent lung infections. Source information for this work is attributed to Nature Communications.
Earlier observations already indicated that the presence of Pseudomonas aeruginosa in the gut correlates with a higher risk of lung infection and mortality. The idea that the intestines might serve as a reservoir from which bacteria migrate to the respiratory tract has been the subject of debate. Recent collaborative studies conducted across England, Spain, and the Netherlands further support this hypothesis, indicating a possible gut-lung axis in the context of bacterial dissemination during or after antibiotic exposure. Source information for this work is attributed to Nature Communications.
The core case underpinning the report centers on a patient admitted to an intensive care unit in Spain who required a prolonged period of mechanical ventilation, totaling 39 days. On the 12th day of care, meropenem was prescribed to address a suspected urinary tract infection. Meropenem is known to be effective against many susceptible bacteria, yet resistant strains of Pseudomonas aeruginosa can survive treatment. In this patient, the bacteria demonstrated the capacity to migrate from the gut to the lungs, a movement confirmed by genetic analysis that traced the respiratory isolates back to intestinal origins. Importantly, the investigation found no evidence that other patients in the same hospital acquired this specific strain, underscoring the complex and individualized nature of bacterial spread in critical care settings. Source information for this work is attributed to Nature Communications.
Should these results be replicated in broader cohorts, they could influence how hospitals approach infection control and antibiotic stewardship. Enhanced screening for gut colonization with Pseudomonas aeruginosa might become part of the risk assessment for patients undergoing prolonged ventilation or facing invasive procedures. The findings also prompt reconsideration of how antibiotic therapy is planned, as selective pressure can inadvertently drive resistant strains toward the lungs, complicating treatment. In addition, the study emphasizes the need for robust, multidisciplinary strategies to prevent nosocomial infections and to reduce pneumonia caused by this resilient organism. Source information for this work is attributed to Nature Communications.