[An experimental examination of the significance of the peak antimicrobial concentration value in urine and time above MIC on the effect of antimicrobial agents--an examination using a severely complicated in vitro bladder model with an autosimulation system for antimicrobial concentration in urine].
Using a severely complicated in vitro bladder model with a computer-controlled autosimulation system for antimicrobial concentration in urine, we examined the significance of the peak concentration value and time above MIC, and obtained the following results. 1. Regarding the initial bactericidal speed, the higher the peak concentration value was, the more quickly the bacterial concentration decreased. 2. Concerning the minimum value of bacterial concentration in the model bladder, the higher the peak concentration value was, the more the level tended to decrease. 3. Regarding inhibition of regrowth of bacteria (ERT) 1) When a particular antimicrobial agent had no PAE on bacteria, the viable bacterial count curve was similar in cases of peak antimicrobial concentration values of higher than 8 MIC. 2) On the other hand, when an antimicrobial agent had PAE on bacteria, regrowth of bacteria occurred quickly below a certain peak concentration (24 MIC or 64 MIC value), although there was some difference depending on the type of antimicrobial agents. Thus, it was suggested that the peak concentration above that level be attained and maintration above that level be attained and maintained for some time were in order to obtain PAE adequately. 4. It is concluded from the aforementioned facts that two factors, a certain high concentration and a certain continued time are necessary for both antimicrobial agent with metabolic disorder and antimicrobial agent with cell wall synthetic inhibition to obtain proper antimicrobial effect. The condition of their necessity differed slightly according to the two different agents.
Nishimura
M
M
Department of Urology, School of Medicine, Sapporo Medical University.
Kumamoto
Y
Y
Hirose
T
T
Ohya
S
S
D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000652:urine*; D004305:Dose-Response Relationship, Drug; D016972:Enterobacter cloacae / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D008826:Microbial Sensitivity Tests / Q000379:methods*; D008954:Models, Biological; D013212:Staphylococcus epidermidis / Q000187:drug effects; D001743:Urinary Bladder; D014556:Urine / Q000382:microbiology*
D000900:Anti-Bacterial Agents