Vol.62 No.2 March 2014

Change in the sensitivity rate for the alternation of breakpoints of the Clinical and Laboratory Standards Institute and rate of the newly defined multidrug-resistant(MDR), extensively drug-resistant(XDR), and pandrug-resistant (PDR) clinical isolates of Pseudomonas aeruginosa

Tetsu Mizutani^1,6), Tetsuro Muratani^2,6), Chikara Nakahama^3,6), Tetsuro Matsumoto^4,6) and Hiroshige Mikamo^5,6)

¹⁾Infection Control Center, Department of Clinical Laboratory, Osaka Police Hospital, 10-31 Kitayama-cho, Tennoji-ku, Osaka, Japan
²⁾Department of Clinical Laboratory, Kyurin Medical Laboratory
³⁾Nakahama Clinic
⁴⁾University of Occupational and Environmental Health Japan
⁵⁾Department of Clinical Infectious Diseases, Aichi Medical University Graduate School of Medicine
⁶⁾Antimicrobial Susceptibility Surveillance Research Group

Abstract

For the alternation from the breakpoint(BP) of Clinical and Laboratory Standards Institute(CLSI) M100-S21 to M100-S22 for 1,021 clinical isolates of Pseudomonas aeruginosa, the sensitivity rates of piperacillin(PIPC), tazobactam/piperacillin(TAZ/PIPC), imipenem/cilastatin(IPM/CS), and meropenem(MEPM) decreased by approximately 10% compared with those for M100-S21. The detection rate of multidrug-resistant P. aeruginosa(MDRP) defined by the Japan Nosocomial Infection Surveillance(JANIS) of the Ministry of Health, Labour and Welfare is 5%. On the other hand, the detection rate of the newly defined multidrug-resistant(MDR), extensively drug-resistant(XDR), and pandrug-resistant(PDR) strains defined by the Center for Disease Control(CDC) and European Committee on Antimicrobial Susceptibility Testing(EUCAST) is 25-35%. MDRP strains are included among MDR, XDR, and PDR strains, and the covering rate of MDRP to MDR, XDR, and PDR is 14-20%, which is extremely low. Investigations of MDR, XDR, and PDR are epidemiologically useful, however, clinical application is difficult because the judgment is complicated. For the early identification of a multidrug resistant strain, and for its rapid control, it is necessary to select a suitable antimicrobial agent and take appropriate measures against nosocomial infections. The use of a new drug-resistant standard, other than a resistant standard of MDRP [resistant to IPM/CS, amikacin(AMK), and ciprofloxacin(CPFX)], is expected to be useful for this purpose.

Key word

Pseudomonas aeruginosa, multidrug resistance, MDR, XDR, PDR

Received

November 18, 2013

Accepted

December 17, 2013

Jpn. J. Chemother. 62 (2): 192-197, 2014