The antibiotic resistance of Pseudomonas aeruginosa strains isolated from various clinical specimens

Abstract

Pseudomonas aeruginosa strains cause serious infections and commonlycolonise in hospital environments. Since these bacteria have a multiple resistance pattern, it is important to determine their antibiotic resistance, particularlyin patients hospitalised at intensive care units (ICU). The aim of this study was to evaluate antimicrobial resistance patterns of P. aeruginosa strains isolated from various clinical specimens of hospitalised patients in Afyon Kocatepe University ANS Hospital. In the years 2007–2008, 188 P. aeruginosa strains were isolated in the Microbiology laboratory and their antibiotic susceptibility was tested by standart disk-diffusion method according to the Clinical and Laboratory Standards Institute (CLSI) criteria. The common specimens were from wound, respiratory tract, blood and urine. Most of the isolates (43.0%) orginated from ICU. The number of resistant strains was 21 (11.1%) for amikacin, 49 (26.0%) for imipenem and meropenem, and 65 (34.5%) for ciprofloxacin as the lower rates. High resistance rates were found for penicillins and cephalosporins, such as 67.0% for piperacillin-tazobactam and 68.6% for ceftazidime. Raised resistance rates were obseved in isolates from the patients hospitalised in ICU, for all tested antibiotics, particularly for carbapenems (43.6%). In conclusion, amikacin and carbapenems were found to be most effective antibiotics for the tested P. aeruginosa isolates. However, dramatically rising resistance rates for carbapenems in ICU isolates and overall high resistance rates to cephalosporins indicate the dimensions of the multiple resistance problem in our hospital.