[In vitro study of combinations between third-generation cephalosporins and aminoglycosides on Enterobacteriaceae].

Four cephalosporins (cefotaxime, moxalactam, cefoperazone and ceftriaxone) were tested in combination with four aminoglycosides (gentamicin, tobramycin, netilmicin and amikacin). We examined 16 clinically isolates of Enterobacteriaceae of which 8 were resistant to newer cephalosporins. The synergy studies was evaluated with a microtiter checkerboard broth dilution. Studies of synergy revealed that cephalosporins in combination with amikacin were often synergistic against third generation cephalosporins resistant strains. These results suggest that amikacin may be facilitate the cephalosporin antibacterial activity.