[The effect of pharmacodynamic parameters of pefloxacin on elastase and protease activity in Pseudomonas aeruginosa].

The effect on Pseudomonas aeruginosa virulence factors (elastase and proteinase) after short-time treatment (30 min) with suprainhibitory (2x or 4x MIC) as well as with supra-subinhibitory concentrations (2x MIC + sub-MICs or 4x MIC + sub-MICs) of pefloxacin was studied. An effective decrease of elastase activity (to 42.6% of the control value) was observed only after higher suprainhibitory antibiotic concentration. More significant depression of the activities tested was found after the postantibiotic effect of subinhibitory concentrations. Elastase as well as proteinase activity were suppressed by supra-subinhibitory concentration of 4x MIC + 0.1x MIC to 13.1% or 37.9%, as compared to controls.