Clinical characteristics of multidrug resistant Pseudomonas aeruginosa bloodstream infection

Objective To analyze the clinical characteristics and drug resistance of multi-drug resistant (MDR) Pseudomonas aeruginosa (PAE) bloodstream infections. Methods Clinical characteristics and drug resistance were analyzed retrospectively based on clinical data about patients with MDR (n=27) or non-MDR (n=40) Pseudomonas aeruginosa bloodstream infections in Air Force Hospital of PLA from January 1, 2013 to June 30, 2016. Results A total of 67 patients were enrolled in this study, including 27 MDR and 40 non-MDR cases with mean age of 57.59±23.43 years in MDR group and 46.48±26.98 years in non-MDR group. There were 19 males in MDR group and 24 males in non-MDR group. Compared with the patients in non-MDR group, patients infected by MDR strains had higher APACHEⅡscore and longer time to positivity of blood cultures (TTP), higher rate of antibiotics usuage more than 7 days within previous one month, and carbapenem antibiotics usuage within previous one month before infection (P< 0.05, respectively). Patients with MDR-PAE infection were more likely to be male, admission to ICU, combined with surgery, with invasive mechanical ventilation, sepsis and septic shock (P< 0.05, respectively). While in non-MDR group, more patients received initial susceptible antibiotic therapy and had greater length of hospital stay after infection when compared with MDR group (P< 0.05). MDR-PAE resisted to imipenem, meropenem and piperacillin with rates of 74.1%, 70.4% and 63% respectively. ROC curves showed that TTP of 15.89 h was the optimal cutoff point to distinguish MDR and non-MDR, with the area under the curve (AUC) of 0.795 (P< 0.001), and the diagnostic accuracy was medium. Conclusion The MDR rate of Pseudomonas aeruginosa in bloodstream infection is high, and patients show severe adverse clinical outcomes and high mortality. TTP can be used as an early indicator in predicting multidrug resistance of Pseudomonas aeruginosa bloodstream infections.