PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 3121667

Disk diffusion susceptibility testing and broth microdilution quality control guidelines for BMY-28100, a new orally administered cephalosporin.

R N Jones·A L Barry
View original source ↗Export metadata ↓

Abstract

The BMY-28100 30-micrograms-disk test was evaluated by using 615 clinical isolates. Regression analyses and error rates were determined, leading to the recommendation of greater than or equal to 18-mm zone diameters (MIC correlate, greater than or equal to 8.0 micrograms/ml) for susceptibility and less than or equal to 14-mm zone diameters (MIC correlate, greater than or equal to 32 micrograms/ml) for resistance. Nearly all false-susceptible disk test results were among the Providencia spp. and the beta-lactamase-positive Haemophilus influenzae strains. Susceptibility disk test results for these species should be interpreted with caution. The following broth microdilution MIC quality control guidelines were determined from results of a multilaboratory trial: Escherichia coli ATCC 25922, 1.0 to 4.0 micrograms/ml; Enterococcus faecalis ATCC 29212, 4.0 to 16 micrograms/ml; Staphylococcus aureus ATCC 29213, 0.25 to 1.0 microgram/ml; and Pseudomonas aeruginosa ATCC 27853, greater than 32 micrograms/ml.

Explore related subjects

CephalosporinsEnterococcus faecalisEscherichia coliHaemophilus influenzaeMicrobial Sensitivity TestsProvidenciaPseudomonas aeruginosaQuality ControlRegression AnalysisStaphylococcus aureusCefprozilJournal ArticleResearch Support, Non-U.S. Gov't

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

R N Jones, A L Barry. 1987. Disk diffusion susceptibility testing and broth microdilution quality control guidelines for BMY-28100, a new orally administered cephalosporin.. https://doi.org/10.1128/jcm.25.11.2211-2213.1987

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2006

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

OBJECTIVES: Enterobacteriaceae with extended-spectrum beta-lactamases (ESBLs) are now widespread and simple phenotypic tests are required to detect them in diagnostic laboratories. We investigated the performance of screening methods at 16 hospitals in South-East England. METHODS: Sixteen laboratories in South-East England submitted 1195 consecutive Enterobacteriaceae isolates found to be resistant, by their routine methods, to any or all of cefpodoxime, ceftazidime and cefotaxime. These isolates were re-tested centrally with various cephalosporin/clavulanate combinations and with multiplex PCR for bla(CTX-M) and bla(AmpC) alleles. RESULTS: Screening methods among the laboratories were the following: cefpodoxime discs alone (1 site); cefpodoxime, cefotaxime and ceftazidime discs (9 sites) or agar dilution (1 site); Phoenix (2 sites), Vitek 1 (1 site) and Vitek 2 (2 sites). A total of 8% of isolates submitted based on disc tests proved fully cephalosporin-susceptible, compared with 3% sent based on tests with automated systems and none of those sent based on agar dilution tests. Among isolates submitted solely on cefpodoxime resistance 256/372 (69%) proved cephalosporin-susceptible or had only borderline resistance with no clear mechanism demonstrable; this proportion decreased to 28/160 (18%) for those submitted on the basis of resistance to ceftazidime, 18/122 (15%) for those resistant to cefotaxime and 26/496 (5%) for those resistant to both cefotaxime and ceftazidime. The inference of ESBL production by Vitek 2 had the best agreement with reference laboratory results. CONCLUSIONS: Many isolates found resistant only to cefpodoxime at the source sites proved not to have ESBLs or AmpC; screening with cefotaxime and ceftazidime allowed better specificity for identification of mechanism-based resistance, as did the automated systems. Cefpodoxime disc tests nevertheless remain a useful primary screen for laboratories prepared only to test one agent.

Cephalosporins↗
PubMed2006

Survival of cephalosporin-resistant enterobacteriaceae on fingers.

Five strains of Enterobacter species (n=4) and Pantoea species (n=1) resistant to third-generation cephalosporins and isolated from clusters of 3-25 premature infants and small children and 5 strains (4 Enterobacter strains and 1 Pantoea strain) with the same resistance pattern that were isolated from 1 premature infant or small child each were inoculated on the fingertips of 10 volunteer study participants to test whether survival on fingertips is correlated with horizontal transmission. Although there was no significant difference in survival between the groups of transmitted and sporadic strains, there were significant differences in bacterial survival between the participants.

Cephalosporins↗