After a brief drying period, a 10 ug
imipenem disc was placed at the centre of the plate and the test isolates were streaked heavily from the edge of the disc toward the edge of the plate.
pneumoniae according to CLSI were assessed for gentamicin (10 [micro]g), aztreonam (30 [micro]g), cefepime (30 [micro]g), cefotaxime (30 [micro]g), cefixime (10 [micro]g), ceftazidime (30 [micro]g), ceftizoxime (30 [micro]g), ciprofloxacin (5 [micro]g), ceftriaxone (30 [micro]g),
imipenem (10 [micro]g), and meropenem (30 [micro]g) (Mast, London, UK), determined by the disk diffusion method.
Augmentation of the inhibition zone around
imipenem and meropenem disk by at least 7 mm in the presence of EDTA was considered to be a positive result in disk difusion, whereas an 8-fold (three dilutions) reduction in the minimum inhibitory concentration (MIC) of
imipenem or meropenem by EDTA was indicative of the production of MBL in dilution test.
The antibacterial agents tested for sensitivity were (Penicillin 1U), Ceftriaxone (30ug), Ceftazidime (30ug), Cefotaxime (30ug), Amoxycillin - Clavulanic Acid (20/10ug), Amikacin (30ug), Piperacillin - Tazobac tam (100/10ug), Trimethoprim-Sulfamethoxazole (1.25/23.75ug),
Imipenem (10ug), Ciprofloxacin (5ug), Norfloxacin (10ug), Ofloxacin (5ug).
It was observed that Escherichia coli isolates exhibited lowest resistance to
Imipenem (1%) followed by nitrofurantoin, meropenem and piperacillin/tazobactam.
Antimicrobial agent MIC range ([micro]g/mL) Amikacin 2-64 Cefepime 1-64 Ceftazidime 1-64 Ceftriaxone 1-64 Ciprofloxacin 0.25-128 Colistin 0.25-128 Ertapenem 0.5-8 Gentamicin 1-16
Imipenem 0.25-16 Meropenem 0.25-16 Piperacillin/tazobactam 4-128 Tigecycline 0.5-8 Antimicrobial agent KPC-Kp Amikacin 4 Cefepime [greater than or equal to]64 Ceftazidime 16 Ceftriaxone [greater than or equal to]64 Ciprofloxacin 64 Colistin [greater than or equal to]128 Ertapenem [greater than or equal to]8 Gentamicin [greater than or equal to]16
Imipenem 8 Meropenem [greater than or equal to]16 Piperacillin/tazobactam [greater than or equal to]128 Tigecycline 2 Antimicrobial agent E.
[5]
Imipenem and meropenem in carbapenems have gained increased therapeutic access in many hospital settings against MDRPA.
The isolates were also tested for resistance to ampicillin, cotrimoxazole, ciprofloxacin, ceftriaxone, doripenem,
imipenem, ertapenem, aztreonam, moxifloxacin, cefpirome, cefepime, gatifloxacin, and chloramphenicol by Kirby-Bauer disc diffusion method.
Imipenem resistant strains were 40(60.6%) of these 18 were found to be resistant to all antibiotics studied.
We previously showed that exposure of carbapenem-heteroresistant KPC-Kp strains to a bactericidal concentration of
imipenem resulted in a reproducible, biphasic pattern of near-complete killing of the population, followed by recovery within 20 hours (h) [11].
We performed a synergy susceptibility testing based on large doses of ceftazidime-clavaminic acid and found that it represented synergism between
imipenem and ceftazidime (Figures 2(a) and 2(b)).
(3,4) Introduction of
imipenem was a cornerstone in treating P.
