IN-VITRO KILLING ACTIVITY OF COMBINATIONS OF BETA-LACTAM AGENTS WITH AMINOGLYCOSIDES AGAINST PENICILLIN-RESISTANT PNEUMOCOCCI

Streptococcus pneumoniae has developed resistance to almost every anti bacterial agent used in clinical practice, including the most active b eta-lactams. This has led to the proposed use of drug combinations. Th e aim of this study was to determine the efficacy of combinations of b eta-lactam agents (cefotaxime or imipenem) with aminoglycosides (genta micin, netilmicin or amikacin) against pneumococci showing high-revel resistance to penicillin and streptomycin and/or kanamycin. All tested combinations were bactericidal and synergic despite the weak concentr ations of antibiotics used. Our results suggest that combinations of b eta-lactam agents with aminoglycosides may be useful for treating infe ctions by penicillin-resistant pneumococci located outside the central nervous system.