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In-Host Evolution of Daptomycin Resistance and Heteroresistance in Methicillin-Resistant Staphylococcus aureus Strains From Three Endocarditis Patients.
- Source :
-
Journal of Infectious Diseases . 2020 Supplement, Vol. 221, pS243-S252. 10p. - Publication Year :
- 2020
-
Abstract
- <bold>Background: </bold>Daptomycin is considered an important alternative for the treatment of methicillin-resistant Staphylococcus aureus (MRSA). However, treatment failures associated with daptomycin nonsusceptibility isolates have been reported in recent years.<bold>Methods: </bold>In this study, we investigated serial MRSA strains from 3 endocarditis patients who had breakthrough bacteremia, despite treatment with daptomycin. The strains were analyzed by whole-genome sequencing, molecular typing, and mutation screening. Population analysis and growth curves were also applied to evaluate heteroresistance and fitness cost.<bold>Results: </bold>This series of MRSA strains belonged to ST5, ST59, and ST4513. The daptomycin minimum inhibitory concentrations for these MRSA strains increased after daptomycin exposure, whereas daptomycin-resistant strains emerged with mutations in mprF and yycH. Population analysis profiling results demonstrated the presence of a daptomycin-heteroresistant subpopulation among daptomycin-susceptible MRSA strains, and no significant fitness cost was observed within these heteroresistant MRSA clones.<bold>Conclusions: </bold>We confirmed that daptomycin heteroresistance and resistance could emerge rapidly in MRSA strains of different lineages after daptomycin exposure. Further studies to fully understand the mechanism(s) underlying daptomycin resistance in MRSA are required. [ABSTRACT FROM AUTHOR]
- Subjects :
- *METHICILLIN-resistant staphylococcus aureus
*ENDOCARDITIS
*BACTERIAL protein analysis
*ANTIBIOTICS
*BACTERIAL proteins
*COMPARATIVE studies
*DRUG resistance in microorganisms
*RESEARCH methodology
*MEDICAL cooperation
*MICROBIAL sensitivity tests
*RESEARCH
*STAPHYLOCOCCAL diseases
*EVALUATION research
*DAPTOMYCIN
*PHARMACODYNAMICS
Subjects
Details
- Language :
- English
- ISSN :
- 00221899
- Volume :
- 221
- Database :
- Academic Search Index
- Journal :
- Journal of Infectious Diseases
- Publication Type :
- Academic Journal
- Accession number :
- 142313796
- Full Text :
- https://doi.org/10.1093/infdis/jiz571