Pseudomonas aeruginosa in tracheal aspirate: Colonization, infection, and recurrence

Introduction Pseudomonas aeruginosa respiratory infections are challenging, and the risk of recurrence is a frequent problem. The aim of this study was to investigate the risk factors associated with the presence of P. aeruginosa, and the risk factors related to the recurrence and death of lower airway infections in inpatients in a Brazilian hospital. Methods Retrospective cohort with inpatients that had a sample of airways culture (tracheal aspirate or bronchoalveolar lavage) with the detection of P. aeruginosa. The patients with clinical criteria of infection were classified as ventilator‐associated, hospital‐acquired, or community‐acquired pneumonia. P. aeruginosa in respiratory samples without symptoms was considered colonization. The antimicrobial treatment adequacy and the clinical data were evaluated. Outcome variables included mortality and recurrence. Results One hundred and fifty‐four patients were included in the study, most of them were men, and the majority (102) were considered infected. The average length of stay was superior to 30 days. Previous pulmonary disease was associated with the occurrence of colonization. Aminoglycosides were the most active drug according to susceptibility tests and were successfully used as monotherapy. Septic shock was a risk factor for death in the infected patients. The use of adequate antimicrobial therapy was associated with major survival, independent of the infection classification. Conclusion It is possible to evaluate clinical data associated with recurrence and mortality in patients with different lung infections by P. aeruginosa. Aminoglycoside monotherapy is safe and effective in P. aeruginosa respiratory infections. Given the recent change challenge in the treatment of the costs of Pseudomonas infection, the need to understand the risk of recurrence and mortality is important. This study demonstrated, despite of intrinsic limitations of the study design, that monotherapy in a short time (