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PubMed · 4840450

Disk susceptibility studies with cefazolin and cephalothin.

P Actor·J Guarini·J Uri·J Dickson·J F Pauls·J A Weisbach
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Abstract

Cefazolin and cephalothin disk susceptibility and minimal inhibitory concentration determinations were conducted on 591 clinical isolates. Cefazolin demonstrated superior activity, as shown by lower minimal inhibitory concentrations, and a greater percentage of isolates inhibited in the disk susceptibility test. The cephalothin antibiotic class disk by the standard Bauer-Kirby method failed to detect susceptibility to cefazolin in a significant percentage of Escherchia coli, Enterobacter species, and Enterococcus isolates. A separate cefazolin disk with a susceptibility cut-off point of 18 mm is recommended. An alternative to a separate cefazolin disk would be a reinterpretation of the cephalothin susceptibility disk zone diameters so that it would more adequately predict cefazolin activity.

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CephalosporinsCephalothinDiffusionEnterobacteriaceaeMicrobial Sensitivity TestsStaphylococcusSulfidesTetrazolesThiadiazolesJournal Article

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BibTeXRIS

P Actor, J Guarini, J Uri, J Dickson, J F Pauls, J A Weisbach. 1974. Disk susceptibility studies with cefazolin and cephalothin.. https://doi.org/10.1128/aac.5.1.63

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Efficacy of practised screening methods for detection of cephalosporin-resistant Enterobacteriaceae.

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