Ceftobiprole met the pre-specified primary efficacy objective of non-inferiority (within the pre-specified margin of 10%) to vancomycin plus
aztreonam in the intent-to-treat (ITT) population.
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.
Maximum resistance was seen with cefotaxime 63.3% and
aztreonam 59.1%.
Except Pseudomonas aeruginosa, which was 63.5% susceptible to
Aztreonam, Klebsiella pneumoniae, E.coli and Acinetobacter spp.
Recently it is reported that NDM-1 producers have the ability escape from effects of
aztreonam making the situation more challenging.
Antibiotic Resistance pattern of Acinetobacter Antibiotics Sensitive Intermediate Resistant Piperacillin/Tazobactum 33(7%) 3(0.7%) 392(92%) Ceftazidine 18(4%) 20(4.6%) 390(92%) Cefoperazone/Sulbactum 100(23%) 66(15%) 262(62%) Cefepime 31(7.2%) 14(3.2%) 383(89.4%)
Aztreonam 10(2.0%) 5(1.16%) 413(95%) Doripenem 37(8.64%) 391(92%) Imipenem 34(7.94%) 8(1.86%) 386(90.1%) Meropenem 39(9.11%) 8(1.86%) 381(89.01%) Amikacin 17(3.97%) 1(0.23%) 410(95.79%) Gentamicin 78(18.22%) 32(7.4%) 318(74%) Ciprofloxacin 30(7.9%) 12(2.80%) 386(90%) Levofloxacin 32(7.4%) 52(12.14%) 344(80.3%) Minocycline 242(56.54%) 46(10.74%) 140(32.7%) Tigecycline 346(80.84%) 75(17.52%) 7(1.63%) Colistin 412(96.26%) 16(3.7%) Cotrimoxazole 69(16.12%) 359(84%) Table 3.
Overall, the highest resistant rate was found for trimethoprim/sulfamethoxazole (79%) followed by cefotaxime (72.9%), cefepime (70%) and
aztreonam (64.6%).
Antibiotic susceptibility testing was determined for this isolates to routinely used antibiotics such as to piperacillintazobactam, cefotaxime, ceftazidime, tetracycline, cotrimoxazole,
aztreonam, gentamicin, and imipenem by Kirby Bauer disc diffusion method as per CLSI guideline.
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.
ESBLs are plasmid mediated enzymes that hydrolyze the oxyimino p lactams and the monobactams (
aztreonam) but have no effect on the cephamycins (cefoxitin, cefotetan) and the carbapenems (imipenem).
The isolate was susceptible to imipenem, meropenem, ertapenem, amikacin, and netilmicin but was resistant to cefotaxime, cefixime, cefepime, and
aztreonam (Table 1).
Among NFGNB the maximum susceptibility was shown by Ciprofloxacin and
Aztreonam whereas Acinetobacter junii showed 100% resistance.
The ceftazidime (CAZ),
aztreonam (AZT), cefotaxime (CTX) and ceftriaxone (CRO) were used for initial screening test.
