Ertapenem susceptibility of extended spectrum beta-lactamase-producing Enterobacteriaceae at a tertiary care centre in India.
BACKGROUND
Infections caused by multidrug-resistant organisms such as extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae have come to assume widespread proportions. Carbapenems (imipenem and meropenem) are the drugs of choice for the treatment of infections caused by ESBL-producing organisms. There is limited clinical data regarding the efficacy of the latest carbapenem, called ertapenem, against these organisms in the Indian subcontinent. In this study, ertapenem susceptibility in ESBL-producing clinical isolates was evaluated. The in vitro activities of the three carbapenems were compared in ertapenem-resistant isolates.


METHODS
A total of 205 ESBL-producing Enterobacteriaceae collected from inpatients and outpatients at the All India Institute of Medical Sciences, were identified and tested for antimicrobial susceptibility by the disc diffusion method and Vitek 2 advanced expert system. Ertapenem susceptibility was performed by disc diffusion and Vitek 2 in all the isolates and by E-test in 100 isolates.


RESULTS
191 (93 percent) of the ESBL-producing isolates tested were susceptible to ertapenem. All ertapenem-susceptible isolates were also susceptible to imipenem and meropenem. Isolates with low-level ertapenem resistance retained their susceptibility to imipenem and meropenem, whereas those with high-level ertapenem resistance were resistant to both imipenem and meropenem.


CONCLUSIONS
Our results suggest that ertapenem may be a viable alternative to other carbapenems for the treatment of infections caused by ESBL-producing clinical isolates. Clinical outcome studies are required to determine if ertapenem is effective for the treatment of infections caused by these organisms.
Behera
B
B
Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India.
Mathur
P
P
Das
A
A
Kapil
A
A
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial; D004755:Enterobacteriaceae / Q000201:enzymology*; D004756:Enterobacteriaceae Infections / Q000188:drug therapy; D000077727:Ertapenem; D006761:Hospitals; D006801:Humans; D007194:India; D008826:Microbial Sensitivity Tests; D001618:beta-Lactamases / Q000378:metabolism*; D047090:beta-Lactams / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D001618:beta-Lactamases; D000077727:Ertapenem