Antimicrobial Effects of Drugs against Multidrug-Resistant Pseudomonas aeruginosa

• Published in: Biological & Pharmaceutical Bulletin 2008/10/01, Vol.31(10), pp.1898-1901
• Main Authors: Maeda, Kumiko, Kobayashi, Youko, Oie, Shigeharu, Ishida, Shiro, Okano, Yoshiro, Kobayashi, Toshihiko, Shikichi, Kyoko, Mizuno, Hidekazu, Kamiya, Akira
• Format: Article
• Language: English
• Subjects: amikacin; Anti-Bacterial Agents - pharmacology; aztreonam; ceftazidime; combined effect; Cross Infection - microbiology; DNA, Bacterial - genetics; Drug Combinations; Drug Resistance, Multiple, Bacterial - drug effects; Humans; Microbial Sensitivity Tests; multidrug-resistant; Pseudomonas aeruginosa; Pseudomonas aeruginosa - drug effects; Pseudomonas Infections - microbiology; Reverse Transcriptase Polymerase Chain Reaction
• ISSN: 0918-6158; 1347-5215
• DOI: 10.1248/bpb.31.1898

We evaluated the effects of antimicrobial drugs on four strains of Pseudomonas aeruginosa that are resistant to eight widely used antipseudomonal drugs (piperacillin, piperacillin-tazobactam, imipenem, meropenem, ceftazidime, aztreonam, amikacin, ciprofloxacin) and colistin. In the killing test, colistin (2 μg/ml) was the most effective, followed by aztreonam (48 μg/ml), piperacillin-tazobactam (192—4 μg/ml), piperacillin (192 μg/ml), and a three drug combination of azetreonam (16 μg/ml), ceftazidime (16 μg/ml), and amikacin (4 μg/ml). Six hours after drug addition, colistin (2 μg/ml), aztreonam (48 μg/ml), piperacillin-tazobactam (192—4 μg/ml), piperacillin (192 μg/ml), and the above three drug combination had bacteriostatic effects on all four strains. Colistin, three time breakpoint of aztreonam, piperacillin, or piperacillin-tazobactam, and the three drug combination of aztreonam, ceftazidime, and amikacin were effective in vitro.