Abstract
The emergence of 16S rRNA methyltransferases (16S RMTases) worldwide is a growing concern due to their ability to confer high-level resistance (minimum inhibitory concentrations (MICs) >256 mg/L) to all clinically relevant aminoglycosides. As the occurrence of 16S RMTases in the United Kingdom has not been investigated to date, we screened 806 Enterobacteriaceae isolates displaying high-level aminoglycoside resistance (amikacin, gentamicin and tobramycin MICs ≥64, ≥32 and ≥32 mg/L, respectively) for 16S RMTases either by analysing whole-genome sequence (WGS) data (which were available for 449 isolates) or by polymerase chain reaction. A total of 94.5% (762/806) pan-aminoglycoside-resistant Enterobacteriaceae were positive for one or more 16S RMTase genes; armA was the most common (340, 44.6%) followed by rmtC (146, 19.2%), rmtF (137, 18.0%), rmtB (87, 11.4%) and various two-gene combinations (52, 6.8%). Most (93.4%; 712/762) 16S RMTase producers also carried acquired carbapenemase genes, with blaNDM the most common (592/712; 83.1%). Additionally, high-risk bacterial clones associated with blaNDM were identified in the subset of isolates with WGS data. These included Escherichia coli sequence types (STs) 405 (21.8%, 19/87), 167 (20.7%, 18/87) 410 (12.6%, 11/87) and K. pneumoniae STs 14 (35.6%, 112/315), 231 (15.6%, 49/315) and 147 (10.5%, 33/315). These accounted for 4.2% (15/358), 5.0% (18/358), 3.1% (11/358), 28.2% (101/358), 3.1% (11/358) and 7.0% (25/358) blaNDM-producing isolates, respectively. This study shows that 16S RMTases occur in the UK and Ireland and carbapenemases are particularly prevalent in 16S RMTase-producing Enterobacteriaceae. This association poses a risk to the treatment of multidrug-resistant Gram-negative infections in the clinical setting.
Original language | English |
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Pages (from-to) | 278-282 |
Number of pages | 5 |
Journal | International Journal of Antimicrobial Agents |
Volume | 52 |
Issue number | 2 |
DOIs | |
Publication status | Published - Aug 2018 |
Bibliographical note
Funding Information:We would like to thank Professor Bruno González-Zorn, Dr Laurent Poirel and Dr Yohei Doi for providing us with bacterial positive controls for rmtF, rmtG and rmtH, respectively. The research was funded by the National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Healthcare Associated Infections and Antimicrobial Resistance at Imperial College London in partnership with Public Health England. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR, the Department of Health or Public Health England.
Funding Information:
Funding: This research was funded by the National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Healthcare Associated Infections and Antimicrobial Resistance at Imperial College London in partnership with Public Health England [HPRU-2012-10047].
Publisher Copyright:
© 2018 Elsevier Ltd
Keywords
- 16S RMTase
- Aminoglycoside resistance
- Multiplex PCR
- bla