SYNERGY BETWEEN TOBRAMYCIN AND NETILMICIN AGAINST 3 STRAINS OF METHICILLIN AND GENTAMICIN-RESISTANT STAPHYLOCOCCI (STAPHYLOCOCCUS-EPIDERMIDIS, STAPHYLOCOCCUS-AUREUS)

The antibacterial effect of tobramycin-netilmicin combination on multi resistant strains of staphylococcus was performed to determine the sig nification of synergy images on diffusion plates. Meticillin and genta micin resistant strains of S. epidermidis (2 strains) and S. aureus (1 strain) were examined and showed an index of combined effect < 0.05 d emonstrating synergy. These values were obtained with aminoglycoside c oncentrations less-than-or-equal-to 4 mg/l, levels which can be consid ered as pharmacologically acceptable. This synergic action can be expl ained by specific inhibition of the resistance enzyme in the strains, possibly in combination with a cooperative effect on the classical tar gets of aminoglycosides. This type of combination using tobramycin and netilmicin could define a new use of aminoglycosides based on the con ception of combining antibiotic enzyme inhibition.