Impact of the Contamination Mode on the Clinical Evolution During Pseudomonas Aeruginosa Ventilator Acquired Pneumonia (PYO GEN)

University Hospital, Grenoble77 enrolled

Overview

Pseudomonas aeruginosa is the main pathogen of nosocomial respiratory infections. Its increasing resistance to antibiotics requires the development of new strategies for prevention and control, demanding a better understanding of the modes of transmission and evolutionary dynamics of this bacteria. In patients under invasive mechanical ventilation, the main mode of contamination by Pseudomonas remains debated, with 3 modes of contamination (endogenous, crossed transmission between patients, or environmental origin) of varying importance, mainly depending on the endemic situation of the place of study. The emergence of new genotyping technologies (DiversiLab) can now facilitate studies of molecular epidemiology. Thanks to the multidisciplinary collaboration and innovative techniques, the investigators wish to study the impact of the mode of contamination on the outcome of ICU patients, intubated and ventilated for more than 72 hours.

The presence of environmental reservoirs can cause infections and multidrug-resistant P. aeruginosa colonization with P. aeruginosa is itself a prognostic factor, but the impact of the route of infection on the evolution of the history and future of the infectious patient is not established. A second factor that may influence the evolution infectious is the degree of genetic heterogeneity of the bacterial population. Multiple exposure pathways could also influence the genetic diversity.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Pseudomonas Aeruginosa Ventilation Acquired Pneumonia

Eligibility

Medical Language ↔ Plain English

Inclusion Criteria: * Patients\> 18 years * hospitalized in the intensive care unit * with more than 72 hours of mechanical ventilation * Presenting a positive bacteriological sample P. aeruginosa. Exclusion Criteria: * Minors. * Pregnant or lactating women. * Patients under guardianship, under judiciary placement, or hospitalized without their consent. * Patients not affiliated to a social security scheme. * Long-term corticosteroid therapy (\> 2mg/kg or\> 1 month before the onset of established infection suspected) * Ongoing chemotherapy, AIDS, transplant patient under immunosuppressive drugs. * Bedridden patient or therapeutic decision at ICU arrival

Outcomes

Primary Outcomes

The occurrence of unfavorable patient's outcome, depending on the mode of contamination, such as persistence, relapse or superinfection of the airways at Day 7, and mortality at Day 28

Time frame: From day 3 of intubation until the end of mechanical ventilation (an average of 28 days).

Secondary Outcomes

Number of different clones of P. aeruginosa found in each sample analyzed for the same patient at diagnosis of colonization and VAP.

Samples of infected patients are analyzed once a week, strains are considered from different clones if their genetic homology rate is below 97%