Study of the in vitro activity of amoxicillin/clavulanic acid and other beta-lactam antibiotics against Escherichia coli isolated from urine specimens.
A total of 205 serial, unduplicated urinary isolates of Escherichia coli was collected from June through August 1998 in 2 community and 3 hospital laboratories. By using the NCCLS broth microdilution technique, their in vitro susceptibility to ampicillin, amoxicillin/clavulanic acid, cefuroxime, cefuroxime axetil, ticarcillin/clavulanic acid and piperacillin/tazobactam was determined. One hundred and twenty isolates were from hospitalised patients, 85 from ambulatory, 129 community acquired and 76 nosocomial. Half of the nosocomial isolates were obtained from naturally produced and half from alternatively produced urine specimens. In general, the highest susceptibility rates, following NCCLS criteria, were found for piperacillin/tazobactam (93.2%) followed by cefuroxime (92.2%) and amoxicillin/clavulanic acid (82.9%). Ampicillin showed a clear bimodal distribution with a clear peak for the resistant population. The highest degree of ampicillin resistance was found in nosocomial isolates. Overall, ampicillin showed the lowest degree of susceptibility. Most of the ampicillin resistant isolates remained susceptible to piperacillin/tazobactam, cefuroxime and amoxicillin/clavulanic acid. In general, the community acquired isolates had higher susceptibility rates than the nosocomial isolates.
Vanhoof
R
R
Pasteurinstituut-Brussel, Eenheid-Antibiotica-onderzoek, Engelandstraat 642, B-1180 Brussel.
Carpentier
M
M
Delannoy
P
P
Fagnart
O
O
Lontie
M
M
Mans
I
I
Nyssen
H J
HJ
Van Nimmen
L
L
D019980:Amoxicillin-Potassium Clavulanate Combination / Q000494:pharmacology*; D000668:Ampicillin Resistance; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001530:Belgium / Q000453:epidemiology; D017714:Community-Acquired Infections / Q000382:microbiology; D003428:Cross Infection / Q000382:microbiology; D004926:Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000652:urine; D006801:Humans; D066298:In Vitro Techniques; D008826:Microbial Sensitivity Tests / Q000706:statistics & numerical data; D018440:beta-Lactam Resistance
D000900:Anti-Bacterial Agents; D019980:Amoxicillin-Potassium Clavulanate Combination