In-vitro susceptibility of Pseudomonas species to fifteen antimicrobial agents.

The in-vitro susceptibility of four Pseudomonas spp. (P. aeruginosa, P. fluorescens, P. maltophilia and P. putida) to 15 antimicrobials was determined. Ciprofloxacin had the greatest in-vitro activity. Although the susceptibility of the different species to individual agents was quite variable, they tended to be less susceptible to agents such as amikacin, aztreonam, cefoperazone, ceftazidime and piperacillin, already in clinical use at our institution, than to newer agents, not currently in clinical use.