caa a22 4500 39759254X CHVBK 20180308164943.0 cr unu---uuuuu 161202e199602 xx s 000 0 eng 10.1093/jac/37.2.233 doi (NATIONALLICENCE)oxford-10.1093/jac/37.2.233 Quantitative comparison in vitro of mutational antibiotic resistance of Enterobacter spp. using a spiral plater [Elektronische Daten] [Chen M. Yu, Joseph W. Chow, Victor L. Yu] The presence of spontaneous mutational antibiotic resistance among 18 bacteremic isolates of Enterobacter spp. to cefotaxime, ceftazidime, gentamicin, amikacin, ciprofloxacin, and trimethoprim-sulfamethoxazole was determined quantitatively in vitro using a spiral plater. Each drug was delivered using the device and the agar plates were inoculated in radial streaks. The degree of resistance was estimated by dividing the antimicrobial concentration required to inhibit 90% of the colonies growing in the area beyond the MIC by the MIC itself. The degree of resistance to third-generation cephalosporins and aztreonam was statistically significantly greater than that to co-trimoxazole, imipenem, and ciprofloxacin (P>0.01); the latter three antibiotics showed virtually no mutational resistance. An intermediate level of resistance was induced by aminoglycosides, and mutational resistance to piperacillin varied between this and the higher levels observed for the cephalosporins. By providing a simple and efficient means of detecting spontaneous mutational resistance, the spiral plater may prove useful in identifying those antimicrobial agents which induce few or no mutants and therefore may be more likely to be successful in treating infections due to Enterobacter spp. © 1996 The British Society for Antimicrobial Chemotherapy Original articles nationallicence Yu Chen M. VA Medical Center and University of Pittsburgh Pittsburgh, PA aut Chow Joseph W. VA Medical Center and University of Pittsburgh Pittsburgh, PA aut Yu Victor L. VA Medical Center and University of Pittsburgh Pittsburgh, PA aut Journal of Antimicrobial Chemotherapy Oxford University Press 37/2(1996-02), 233-242 0305-7453 37:2<233 1996 37 jac https://doi.org/10.1093/jac/37.2.233 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/jac/37.2.233 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Yu Chen M. VA Medical Center and University of Pittsburgh Pittsburgh, PA aut NATIONALLICENCE 700 1- Chow Joseph W. VA Medical Center and University of Pittsburgh Pittsburgh, PA aut NATIONALLICENCE 700 1- Yu Victor L. VA Medical Center and University of Pittsburgh Pittsburgh, PA aut NATIONALLICENCE 773 0- Journal of Antimicrobial Chemotherapy Oxford University Press 37/2(1996-02), 233-242 0305-7453 37:2<233 1996 37 jac Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford