Validating a screening agar for linezolid-resistant enterococci
Abstract Background Linezolid is an alternative treatment option for infections with multidrug-resistant Gram-positive bacteria including vancomycin-resistant enterococci. Some countries report an increasing number of isolates with resistance to linezolid. The recent publication of the Commission fo...
Main Authors: | , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
BMC
2019-12-01
|
Series: | BMC Infectious Diseases |
Subjects: | |
Online Access: | https://doi.org/10.1186/s12879-019-4711-y |
id |
doaj-c019acf1350b4a3f83617c5239ecec07 |
---|---|
record_format |
Article |
spelling |
doaj-c019acf1350b4a3f83617c5239ecec072020-12-27T12:03:38ZengBMCBMC Infectious Diseases1471-23342019-12-011911510.1186/s12879-019-4711-yValidating a screening agar for linezolid-resistant enterococciGuido Werner0Carola Fleige1Ingo Klare2Robert E. Weber3Jennifer K. Bender4Division Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, National Reference Centre for Staphylococci and Enterococci (NRC), Robert Koch Institute, Wernigerode BranchDivision Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, National Reference Centre for Staphylococci and Enterococci (NRC), Robert Koch Institute, Wernigerode BranchDivision Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, National Reference Centre for Staphylococci and Enterococci (NRC), Robert Koch Institute, Wernigerode BranchDivision Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, National Reference Centre for Staphylococci and Enterococci (NRC), Robert Koch Institute, Wernigerode BranchDivision Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, National Reference Centre for Staphylococci and Enterococci (NRC), Robert Koch Institute, Wernigerode BranchAbstract Background Linezolid is an alternative treatment option for infections with multidrug-resistant Gram-positive bacteria including vancomycin-resistant enterococci. Some countries report an increasing number of isolates with resistance to linezolid. The recent publication of the Commission for Hospital Hygiene in Germany on enterococci/VRE recommends screening for linezolid-resistant enterococci (LRE). However, a suitable selective medium or a genetic test is not available. Our aim was to establish a selective screening agar for LRE detection and validate its application with a comprehensive collection of clinical LRE and linezolid-susceptible enterococci. Methods We decided to combine the selective power of an enterococcal screening agar with a supplementation of linezolid. Several rounds of analyses with reference, control and test strains and under varying linezolid concentrations of a wider and a smaller range were investigated and assessed. The collection of linezolid-resistant enterococcal control strains included isolates with different resistance mechanisms (23S rDNA mutations, cfr(B), optrA, poxtA). Finally, we validated our LRE screening agar with 400 samples sent to our National Reference Centre in 2019. Results Several rounds of pre-tests and confirmatory analyses favored Enterococcosel® Agar supplemented with a concentration of 2 mg/L linezolid. A 48 h incubation period was essential for accurate identification of LRE strains. Performance of the LRE screening agar revealed a sensitivity of 96.6% and a specificity of 94.4%. Conclusions Here we describe preparation of a suitable screening agar and a procedure to identify LRE isolates with high accuracy.https://doi.org/10.1186/s12879-019-4711-ycfr(B)optrApoxtALinezolid resistance |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Guido Werner Carola Fleige Ingo Klare Robert E. Weber Jennifer K. Bender |
spellingShingle |
Guido Werner Carola Fleige Ingo Klare Robert E. Weber Jennifer K. Bender Validating a screening agar for linezolid-resistant enterococci BMC Infectious Diseases cfr(B) optrA poxtA Linezolid resistance |
author_facet |
Guido Werner Carola Fleige Ingo Klare Robert E. Weber Jennifer K. Bender |
author_sort |
Guido Werner |
title |
Validating a screening agar for linezolid-resistant enterococci |
title_short |
Validating a screening agar for linezolid-resistant enterococci |
title_full |
Validating a screening agar for linezolid-resistant enterococci |
title_fullStr |
Validating a screening agar for linezolid-resistant enterococci |
title_full_unstemmed |
Validating a screening agar for linezolid-resistant enterococci |
title_sort |
validating a screening agar for linezolid-resistant enterococci |
publisher |
BMC |
series |
BMC Infectious Diseases |
issn |
1471-2334 |
publishDate |
2019-12-01 |
description |
Abstract Background Linezolid is an alternative treatment option for infections with multidrug-resistant Gram-positive bacteria including vancomycin-resistant enterococci. Some countries report an increasing number of isolates with resistance to linezolid. The recent publication of the Commission for Hospital Hygiene in Germany on enterococci/VRE recommends screening for linezolid-resistant enterococci (LRE). However, a suitable selective medium or a genetic test is not available. Our aim was to establish a selective screening agar for LRE detection and validate its application with a comprehensive collection of clinical LRE and linezolid-susceptible enterococci. Methods We decided to combine the selective power of an enterococcal screening agar with a supplementation of linezolid. Several rounds of analyses with reference, control and test strains and under varying linezolid concentrations of a wider and a smaller range were investigated and assessed. The collection of linezolid-resistant enterococcal control strains included isolates with different resistance mechanisms (23S rDNA mutations, cfr(B), optrA, poxtA). Finally, we validated our LRE screening agar with 400 samples sent to our National Reference Centre in 2019. Results Several rounds of pre-tests and confirmatory analyses favored Enterococcosel® Agar supplemented with a concentration of 2 mg/L linezolid. A 48 h incubation period was essential for accurate identification of LRE strains. Performance of the LRE screening agar revealed a sensitivity of 96.6% and a specificity of 94.4%. Conclusions Here we describe preparation of a suitable screening agar and a procedure to identify LRE isolates with high accuracy. |
topic |
cfr(B) optrA poxtA Linezolid resistance |
url |
https://doi.org/10.1186/s12879-019-4711-y |
work_keys_str_mv |
AT guidowerner validatingascreeningagarforlinezolidresistantenterococci AT carolafleige validatingascreeningagarforlinezolidresistantenterococci AT ingoklare validatingascreeningagarforlinezolidresistantenterococci AT roberteweber validatingascreeningagarforlinezolidresistantenterococci AT jenniferkbender validatingascreeningagarforlinezolidresistantenterococci |
_version_ |
1724369529396527104 |