الفهرس 
Pseudomonas GenusOnly 14 pages are availabe for public view
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Abstract
Combination therapy is used to widen the antimicrobial spectrum,
minimize toxicity and prevent the emergence of resistant mutants.
Antimicrobial synergy resulting from antibiotic combination therapy is
often important in the treatment of serious bacterial infections.
The purpose of the present study is to determine the in-vitro activities of
aminoglycosides (amikacin) in combination with third-generation
cephalosporins (cefoperazone), antipseudomonal pencillins (piperacillin –
tazobactem), carbapenems(meropenem),fluoroquinolones(ciprofloxacin)
and polymixins (colistin) against MDR isolates of pseudomonas spp.
And P. aeruginosa ATCC 27853 that was used as a quality control strain
throughout the study.
The effects of these antibiotic combinations were examined by two
methods (disk diffusion, and checkerboard).Fractional inhibitory
concentration indices were calculated for all isolates with all
combinations. Use of the disk diffusion method revealed that amikacin in
combination with the β-lactams and ciprofloxacin exhibited synergy
against 70% of isolates, whereas the combinations of amikacin and
colistin displayed synergic effects against 80% of isolates .Using the
checkerboard method , all of the combinations exhibited synergic effects
against all the isolates. No antagonism was found with these
combinations.
The result of this study indicates that synergism may occur between
aminoglycosides, β-lactams and fluoroquinolones although the strains are
resistant to the individual antibiotics.
Key Words:
Antimicrobial combinations, Checkerboard titration method, β-lactams
Aminoglycosides