Antibacterial activity of cefoperazone alone and in combination with aminoglycoside antibiotics

ABSTRACT

The in-vitro antibacterial activities of cefoperazone [Cef], amikacin [Am], tobramycin [Nn] and gentamicin [Gm] as well as the combinations of cefoperazone with the three aminoglycoside antibiotics were tested againts five strains of each of Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus using the checkerboard agar dilution method. All antimicrobial combinations demonstrated some synergy and no antagonism was observed. A synergistic effect was observed with the combinations of cefoperazone plus amikacin, cefoperazone plus tobramycin and cefoperazone plus gentamicin against four of five and three of five of the tested clinical isolates of Pseudomonas aeruginosa and Escherichia coli respectively. Staphylococcus aureus clinical isolates exhibit an additive or indifferent effect towards all tested combinations. No antagonistic activities were found with any of the strains using such combinations