Phenotypic and genotypic analysis of antimicrobial resistance in Nocardia species.
Journal
The Journal of antimicrobial chemotherapy
ISSN: 1460-2091
Titre abrégé: J Antimicrob Chemother
Pays: England
ID NLM: 7513617
Informations de publication
Date de publication:
05 09 2023
05 09 2023
Historique:
received:
27
05
2023
accepted:
19
07
2023
medline:
6
9
2023
pubmed:
1
8
2023
entrez:
1
8
2023
Statut:
ppublish
Résumé
Antimicrobial resistance is common in Nocardia species but data regarding the molecular mechanisms beyond their resistance traits are limited. Our study aimed to determine the species distribution, the antimicrobial susceptibility profiles, and investigate the associations between the resistance traits and their genotypic determinants. The study included 138 clinical strains of Nocardia from nine Israeli microbiology laboratories. MIC values of 12 antimicrobial agents were determined using broth microdilution. WGS was performed on 129 isolates of the eight predominant species. Bioinformatic analysis included phylogeny and determination of antimicrobial resistance genes and mutations. Among the isolates, Nocardia cyriacigeorgica was the most common species (36%), followed by Nocardia farcinica (16%), Nocardia wallacei (13%), Nocardia abscessus (9%) and Nocardia brasiliensis (8%). Linezolid was active against all isolates, followed by trimethoprim/sulfamethoxazole (93%) and amikacin (91%). Resistance to other antibiotics was species-specific, often associated with the presence of resistance genes or mutations: (1) aph(2″) in N. farcinica and N. wallacei (resistance to tobramycin); (ii) blaAST-1 in N. cyriacigeorgica and Nocardia neocaledoniensis (resistance to amoxicillin/clavulanate); (iii) blaFAR-1 in N. farcinica (resistance to ceftriaxone); (iv) Ser83Ala substitution in the gyrA gene in four species (resistance to ciprofloxacin); and (v) the 16S rRNA m1A1408 methyltransferase in N. wallacei isolates (correlating with amikacin resistance). Our study provides a comprehensive understanding of Nocardia species diversity, antibiotic resistance patterns, and the molecular basis of antimicrobial resistance. Resistance appears to follow species-related patterns, suggesting a lesser role for de novo evolution or transmission of antimicrobial resistance.
Sections du résumé
BACKGROUND
Antimicrobial resistance is common in Nocardia species but data regarding the molecular mechanisms beyond their resistance traits are limited. Our study aimed to determine the species distribution, the antimicrobial susceptibility profiles, and investigate the associations between the resistance traits and their genotypic determinants.
METHODS
The study included 138 clinical strains of Nocardia from nine Israeli microbiology laboratories. MIC values of 12 antimicrobial agents were determined using broth microdilution. WGS was performed on 129 isolates of the eight predominant species. Bioinformatic analysis included phylogeny and determination of antimicrobial resistance genes and mutations.
RESULTS
Among the isolates, Nocardia cyriacigeorgica was the most common species (36%), followed by Nocardia farcinica (16%), Nocardia wallacei (13%), Nocardia abscessus (9%) and Nocardia brasiliensis (8%). Linezolid was active against all isolates, followed by trimethoprim/sulfamethoxazole (93%) and amikacin (91%). Resistance to other antibiotics was species-specific, often associated with the presence of resistance genes or mutations: (1) aph(2″) in N. farcinica and N. wallacei (resistance to tobramycin); (ii) blaAST-1 in N. cyriacigeorgica and Nocardia neocaledoniensis (resistance to amoxicillin/clavulanate); (iii) blaFAR-1 in N. farcinica (resistance to ceftriaxone); (iv) Ser83Ala substitution in the gyrA gene in four species (resistance to ciprofloxacin); and (v) the 16S rRNA m1A1408 methyltransferase in N. wallacei isolates (correlating with amikacin resistance).
CONCLUSIONS
Our study provides a comprehensive understanding of Nocardia species diversity, antibiotic resistance patterns, and the molecular basis of antimicrobial resistance. Resistance appears to follow species-related patterns, suggesting a lesser role for de novo evolution or transmission of antimicrobial resistance.
Identifiants
pubmed: 37527397
pii: 7234730
doi: 10.1093/jac/dkad236
doi:
Substances chimiques
Anti-Bacterial Agents
0
Amikacin
84319SGC3C
RNA, Ribosomal, 16S
0
Anti-Infective Agents
0
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
2306-2314Commentaires et corrections
Type : ErratumIn
Informations de copyright
© The Author(s) 2023. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.