Résumé
Aim of study. - Monitor evolution of antibiotic resistance of Pseudomonas aeruginosa from 2002 to 2006 in our hospital to optimize antibiotherapy.
Patients and method. - The infections/colonizations with P. aeruginosa have been identified by the hospital's informatic database. Bacteriological samples realized 48 hours after patient's admission was considered as nosocomial. A Cochran-Armitage test was conducted to assess the evolution of resistance.
Results. - During this period, 2098 infections/colonizations with P. aeruginosa have been identified. Bacteriological samples (68.5%) were nosocomial. Among the beta-lactam antibiotics, ceftazidime and imipenem were the most active (R = 16.8% and 15.2%, respectively), followed by piperacillin and piperacillin-tazobactam (R = 24.8%, 18.4%, respectively). Amikacin and tobramycin were more active than gentamicin (R = 19.9%; 22.2% and 40.6%, respectively). 28.9% of strains were resistant to ciprofloxacin. Nosocomial strains were significantly more resistant than non-hospital strains: ceftazidime: 17.9% versus 14.2%, p = 0.0346; ticarcillin-clavulanic acid: 47.5% versus 39.6%, p = 0.0009; piperacillin-tazobactam: 20.0% versus 14.8%, p = 0.0046; ciprofloxacin: 30.7% versus 25.2%, p = 0.0112. A significant increase in the resistance of nosocomial strains to ceftazidime, ticarcillin-clavulanic acid and piperacillin-tazobactam was noted. Resistance from non-hospital strains to fluoroquinolones, aminoglycosides, ceftazidime, piperacillin and ticarcillin-clavulanic acid decreased significantly.
Conclusion. - P. aeruginosa is a predominantly nosocomial microorganism. There is a decrease of resistance for non-hospital strains. But the resistance of nosocomial strains to antibiotics widely prescribed in hospital is worrying. (C) 2009 Elsevier Masson SAS. All rights reserved.