Objective:

Escherichia coli (EC) and Klebsiella spp. (KL) are the main producers of ESBL and the highest ESBL rates were found in ICU patients in Eastern Europe. Here we present the data on resistance patterns of EC and KL, including possible ESBL-producers, from Russian centre participating in MYSTIC Programme.

Methods:

From 26 to 43 consecutive, nonrepetitive, clinically significant isolates of EC and KL from ICU patients with hospital-acquired infections were collected prospectively each year from 1997 to 2003. Identification of isolates was performed by routine laboratory techniques; MICs of meropenem, imipenem, ceftazidime, cefepime piperacillin/tazobactam, ciprofloxacin and gentamicin were determined by the standard microdilution procedure and interpreted according to NCCLS criteria. Ceftazidime/clavulanate combination was used for phenotypic confirmation of possible ESBL production according to NCCLS recommendations.

Results:

During the study period the prevalence of ESBL producers increased among EC isolates from 20 to 40%. Among KL isolates ESBL production varied from 40 to 70% in different years. ESBL production was strongly associated with gentamicin and ciprofloxacin resistance. No carbapenem resistance was detected among available isolates. Cefepime demonstrated significantly lower MICs against ESBL producers in comparison with ceftazidime. High-level piperacillin/tazobactam resistance varied between 10 and 20%, but intermediate resistance exceeded 40%.

Conclusions:

Carbapenems are valuable options in the treatment of EC and KL hospital-acquired infections in ICUs with high prevalence of ESBL production.