In vitro activity of ertapenem and other carbapenems against extended-spectrum beta-lactamase producing Escherichia coli and Klebsiella pneumoniae clinical isolates in a tertiary care center in Turkey.
OBJECTIVE
To evaluate the in vitro effect of ertapenem, imipenem and meropenem in clinical isolates of extended-spectrum beta-lactamase (ESBL)-producing strains of Escherichia coli and Klebsiella pneumoniae.


METHODS
We studied 82 consecutive clinical isolates of ESBL-producing E. coli (n = 49) and K. pneumonia (n = 33) between February 2006 and September 2007. The minimum inhibitory concentration for each carbapenem was determined using the agar dilution method.


RESULTS
Eighty two consecutive microorganisms from sterile sites were evaluated. A total of 48.8% of patients had a history of surgical intervention, 78.0% needed urinary catheterization, 57.3% required vascular access and 40.3% mechanical ventilation; and 70.7% had a history of ICU stay. High resistance rates were shown for both E. coli and K. pneumoniae against cefepime (81.7%), ciprofloxacin (50.9%), tetracycline (75.0%), co-trimoxazole (47.4%), and gentamicin (48.7%). In addition, most K. pneumoniae and E. coli isolates were susceptible to amikacin (78.3%) and piperacilline-tazobactam (91.5%). Meropenem and imipenem showed activity against 100% of the isolates. Ertapenem showed activity against 100% of K. pneumoniae isolates, against 95.9% of E. coli isolates and against 97.5% of the 82 ESBL-producing microorganisms. Two E. coli isolates showed ertapenem resistance.


CONCLUSIONS
In recent literature, carbapenems were the most active antimicrobial agents against ESBL-producing Enterobacteriaceae, as in our study. This is the first study on the in vitro activity of ertapenem against ESBL-producing E. coli and K. pneumoniae conducted in Turkey. In view of the serious infections caused by ESBL-producing microorganisms, therapeutic interventions are still problematic in serious clinical conditions. Ertapenem may be a good choice for treatment, with the additional advantage of being a once a day regimen.
Eskisehir Osmangazi University, Faculty of Medicine, Department of Medical Microbiology, TR-26480 Eskisehir, Turkey.
Abdurrahman
A
Kiremitci
Ener Cagri
EC
Dinleyici
Nurettin
N
Erben
Gul
G
Durmaz
Zeynel Abidin
ZA
Yargic
Askin Derya
AD
Aybey
Gaye
G
Usluer
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015780:Carbapenems / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D000077727:Ertapenem; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification; D005260:Female; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D014421:Turkey; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000096:biosynthesis; D047090:beta-Lactams / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D015780:Carbapenems; D065093:beta-Lactamase Inhibitors; D047090:beta-Lactams; D001618:beta-Lactamases; D000077727:Ertapenem