The effect of aminoglycoside-induced adaptive resistance on the antibacterial activity of other antibiotics against Pseudomonas aeruginosa in vitro.

The effect of gentamicin-induced adaptive resistance on the antibacterial activity of six non-aminoglycoside antibiotics was studied. Adaptive resistance was induced in Pseudomonas aeruginosa in a dynamic in-vitro model of infection. The bactericidal effect of ceftazidime, imipenem, aztreonam, ciprofloxacin, and piperacillin was not altered in the presence of adaptive resistance but the effect of rifampicin was increased.