Antibiotic Susceptibility of Clinical Isolates of Pseudomonas Aeruginosa

• Main Author: Siva Gowri Pathmanathan
• Format: Research Report
• Language: English
• Published: Universiti Sains Islam Malaysia 2011
• Subjects: Drug Resistance, Microbial
• Online Access: http://ddms.usim.edu.my/handle/123456789/4100

Ongoing surveillance of Pseudomonas aeruginosa resistance against antimicrobial agents is fundamental to monitor trends in its susceptibility patterns and to appropriately guide clinicians in choosing empirical or directed therapy. The current in vitro activity level of eight antimicrobial drugs was assessed against 97 clinical isolates of P. aeruginosa collected consecutively for three months in 2007 from a Malaysian hospital. Antimicrobial susceptibility was determined using the Etest method subsequent to the hospital's routine diagnostic testing by the disk diffusion method. Respiratory isolates, followed by wound swab isolates were the most frequently encountered. The Etest and disk diffusion methods showed high agreement in determining the in vitro activity of the antimicrobial agents on the P. aeruginosa isolates. Etest results showed piperacillin-tazobactam was the most active antimicrobial agent with 91.8% susceptibility, followed by the aminoglycosides (amikacin, 86.6% and gentamicin, 84.5%), the quinolone (ciprofloxacin, 83.5%) and the beta-lactams (cefepime, 80.4%, ceftazidime, 80.4%, imipenem, 79.4% and meropenem, 77.3%). Incidence of multidrug-resistance was 19.6% (19 out of 97 isolates). The higher resistance rate in general as compared to previous studies call for prudent use of antibiotics in order to limit further increase in resistance. Periodical surveillance of antibiotic resistance is fundamental to monitor changes in susceptibility patterns in a hospital setting. A standard definition of Pseudomonas aeruginosa multidrug resistance is crucially needed to allow better comparisons between studies.