Tags

Type your tag names separated by a space and hit enter

Antimicrobial susceptibility testing of Enterobacteriaceae: determination of disk content and Kirby-Bauer breakpoint for ceftazidime/avibactam.
BMC Microbiol. 2019 11 01; 19(1):240.BM

Abstract

BACKGROUND

Detection of ceftazidime/avibactam (CAZ/AVI) antibacterial activity is absolutely vital with the rapid growth of carbapenem resistant Enterobacteriaceae (CRE). But now, there is no available automated antimicrobial susceptibility testing card for CAZ/AVI, so Kirby-Bauer has become an economical and practical method for detecting CAZ/AVI antibacterial activity against Enterobacteriaceae.

RESULT

In this study, antimicrobial susceptibility testing of CAZ/AVI against 386 Enterobacteriaceae (188 Klebsiella pneumoniae, 122 Escherichia coli, 76 Enterobacter cloacae) isolated from clinical patients was performed by broth microdilution. Of the 386 strains, 54 extended spectrum β lactamases negative (ESBL(-)), 104 extended spectrum β lactamases positive (ESBL(+)), 228 CRE. 287 isolates were susceptible to CAZ/AVI and 99 isolates were resistant to CAZ/AVI. At the same time, to obtain optimal content avibactam (AVI) disk containing ceftazidime (30 μg), inhibition zone diameter of four kinds of ceftazidime (30 μg) disk containing different AVI content (0 μg, 10 μg, 25 μg, 50 μg) were tested by Kirby-Bauer method. The microdilution broth method interpretation was used as the standard to estimate susceptible or resistance and then coherence analysis was carried out between Kirby-Bauer and broth microdilution. The result shows the inhibition zone diameter of 30 μg/50 μg disk, susceptible isolates: 20.5 mm-31.5 mm, resistance isolates: 8.25 mm-21.5 mm. The inhibition zone diameter of 30 μg/25 μg disk, susceptible isolates: 19.7 mm-31.3 mm, resistance isolates: 6.5 mm-19.2 mm. The inhibition zone diameter of 30 μg/10 μg disk, susceptible isolates: 19.5 mm-31 mm, resistance isolates: 6.5 mm-11 mm. The inhibition zone diameter of ceftazidime (30 μg), susceptible isolates: 6.5 mm-27.5 mm, resistance isolates 6.5 mm.

CONCLUSION

Our results show that 30 μg/50 μg, 30 μg/25 μg, 30 μg/10 μg CAZ/AVI disk have significant statistical differences to determinate CAZ/AVI antibacterial activity, but for 30 μg/50 μg disk, there has a cross section between susceptible isolates (minimum 20.5 mm) and resistance isolates (maximum 21.5 mm). For 30 μg/25 μg disk, it is hard to distinguish the difference between susceptible isolates (minimum 19.7 mm) and resistance isolates (maximum 19.2 mm), so 30 μg/10 μg CAZ/AVI disk is more conducive to determinate antibacterial activity.

Authors+Show Affiliations

Department of Laboratory Medicine, the First Affiliated Hospital of Chengdu Medical College, 278 Baoguang Road, Xindu, Chengdu, Sichuan, 610500, People's Republic of China.Department of Laboratory Medicine, the First Affiliated Hospital of Chengdu Medical College, 278 Baoguang Road, Xindu, Chengdu, Sichuan, 610500, People's Republic of China.Department of Laboratory Medicine, the First Affiliated Hospital of Chengdu Medical College, 278 Baoguang Road, Xindu, Chengdu, Sichuan, 610500, People's Republic of China.Department of Laboratory Medicine, the First Affiliated Hospital of Chengdu Medical College, 278 Baoguang Road, Xindu, Chengdu, Sichuan, 610500, People's Republic of China.Department of Laboratory Medicine, the First Affiliated Hospital of Chengdu Medical College, 278 Baoguang Road, Xindu, Chengdu, Sichuan, 610500, People's Republic of China.Department of Laboratory Medicine, the First Affiliated Hospital of Chengdu Medical College, 278 Baoguang Road, Xindu, Chengdu, Sichuan, 610500, People's Republic of China.Department of Laboratory Medicine, the First Affiliated Hospital of Chengdu Medical College, 278 Baoguang Road, Xindu, Chengdu, Sichuan, 610500, People's Republic of China.Department of Laboratory Medicine, the First Affiliated Hospital of Chengdu Medical College, 278 Baoguang Road, Xindu, Chengdu, Sichuan, 610500, People's Republic of China.Department of Laboratory Medicine, the First Affiliated Hospital of Chengdu Medical College, 278 Baoguang Road, Xindu, Chengdu, Sichuan, 610500, People's Republic of China. yingxu@cmc.edu.cn.

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

31675928

Citation

Yang, Xianggui, et al. "Antimicrobial Susceptibility Testing of Enterobacteriaceae: Determination of Disk Content and Kirby-Bauer Breakpoint for Ceftazidime/avibactam." BMC Microbiology, vol. 19, no. 1, 2019, p. 240.
Yang X, Wang D, Zhou Q, et al. Antimicrobial susceptibility testing of Enterobacteriaceae: determination of disk content and Kirby-Bauer breakpoint for ceftazidime/avibactam. BMC Microbiol. 2019;19(1):240.
Yang, X., Wang, D., Zhou, Q., Nie, F., Du, H., Pang, X., Fan, Y., Bai, T., & Xu, Y. (2019). Antimicrobial susceptibility testing of Enterobacteriaceae: determination of disk content and Kirby-Bauer breakpoint for ceftazidime/avibactam. BMC Microbiology, 19(1), 240. https://doi.org/10.1186/s12866-019-1613-5
Yang X, et al. Antimicrobial Susceptibility Testing of Enterobacteriaceae: Determination of Disk Content and Kirby-Bauer Breakpoint for Ceftazidime/avibactam. BMC Microbiol. 2019 11 1;19(1):240. PubMed PMID: 31675928.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Antimicrobial susceptibility testing of Enterobacteriaceae: determination of disk content and Kirby-Bauer breakpoint for ceftazidime/avibactam. AU - Yang,Xianggui, AU - Wang,Dan, AU - Zhou,Qin, AU - Nie,Fang, AU - Du,Hongfei, AU - Pang,Xueli, AU - Fan,Yingzi, AU - Bai,Tingting, AU - Xu,Ying, Y1 - 2019/11/01/ PY - 2019/01/08/received PY - 2019/10/15/accepted PY - 2019/11/3/entrez PY - 2019/11/5/pubmed PY - 2020/7/30/medline KW - Ceftazidime/avibactam KW - Disk content KW - Enterobacteriaceae KW - Kirby-Bauer breakpoints SP - 240 EP - 240 JF - BMC microbiology JO - BMC Microbiol. VL - 19 IS - 1 N2 - BACKGROUND: Detection of ceftazidime/avibactam (CAZ/AVI) antibacterial activity is absolutely vital with the rapid growth of carbapenem resistant Enterobacteriaceae (CRE). But now, there is no available automated antimicrobial susceptibility testing card for CAZ/AVI, so Kirby-Bauer has become an economical and practical method for detecting CAZ/AVI antibacterial activity against Enterobacteriaceae. RESULT: In this study, antimicrobial susceptibility testing of CAZ/AVI against 386 Enterobacteriaceae (188 Klebsiella pneumoniae, 122 Escherichia coli, 76 Enterobacter cloacae) isolated from clinical patients was performed by broth microdilution. Of the 386 strains, 54 extended spectrum β lactamases negative (ESBL(-)), 104 extended spectrum β lactamases positive (ESBL(+)), 228 CRE. 287 isolates were susceptible to CAZ/AVI and 99 isolates were resistant to CAZ/AVI. At the same time, to obtain optimal content avibactam (AVI) disk containing ceftazidime (30 μg), inhibition zone diameter of four kinds of ceftazidime (30 μg) disk containing different AVI content (0 μg, 10 μg, 25 μg, 50 μg) were tested by Kirby-Bauer method. The microdilution broth method interpretation was used as the standard to estimate susceptible or resistance and then coherence analysis was carried out between Kirby-Bauer and broth microdilution. The result shows the inhibition zone diameter of 30 μg/50 μg disk, susceptible isolates: 20.5 mm-31.5 mm, resistance isolates: 8.25 mm-21.5 mm. The inhibition zone diameter of 30 μg/25 μg disk, susceptible isolates: 19.7 mm-31.3 mm, resistance isolates: 6.5 mm-19.2 mm. The inhibition zone diameter of 30 μg/10 μg disk, susceptible isolates: 19.5 mm-31 mm, resistance isolates: 6.5 mm-11 mm. The inhibition zone diameter of ceftazidime (30 μg), susceptible isolates: 6.5 mm-27.5 mm, resistance isolates 6.5 mm. CONCLUSION: Our results show that 30 μg/50 μg, 30 μg/25 μg, 30 μg/10 μg CAZ/AVI disk have significant statistical differences to determinate CAZ/AVI antibacterial activity, but for 30 μg/50 μg disk, there has a cross section between susceptible isolates (minimum 20.5 mm) and resistance isolates (maximum 21.5 mm). For 30 μg/25 μg disk, it is hard to distinguish the difference between susceptible isolates (minimum 19.7 mm) and resistance isolates (maximum 19.2 mm), so 30 μg/10 μg CAZ/AVI disk is more conducive to determinate antibacterial activity. SN - 1471-2180 UR - https://www.unboundmedicine.com/medline/citation/31675928/Antimicrobial_susceptibility_testing_of_Enterobacteriaceae:_determination_of_disk_content_and_Kirby_Bauer_breakpoint_for_ceftazidime/avibactam_ DB - PRIME DP - Unbound Medicine ER -