Clinical implications of reduced susceptibility to fluoroquinolones in paediatric Shigella sonnei and Shigella flexneri infections

<br xmlns:etd="http://www.ouls.ox.ac.uk/ora/modsextensions"><strong>Objectives: </strong>We aimed to quantify the impact of fluoroquinolone resistance on the clinical outcome of paediatric shigellosis patients treated with fluoroquinolones in southern Vietnam. Such inform...

Full description

Bibliographic Details
Main Authors: Thompson, C, Thieu, N, Vinh, P, Duc, A, Wolbers, M, Vinh, H, Campbell, J, Ngoc, D, Hoang, N, Thanh, T, The, H, Nguyen, T, Lan, N, Parry, C, Chau, N, Thwaites, G, Thanh, D, Baker, S
Format: Journal article
Language:English
Published: Oxford University Press 2015
_version_ 1797067118995308544
author Thompson, C
Thieu, N
Vinh, P
Duc, A
Wolbers, M
Vinh, H
Campbell, J
Ngoc, D
Hoang, N
Thanh, T
The, H
Nguyen, T
Lan, N
Parry, C
Chau, N
Thwaites, G
Thanh, D
Baker, S
author_facet Thompson, C
Thieu, N
Vinh, P
Duc, A
Wolbers, M
Vinh, H
Campbell, J
Ngoc, D
Hoang, N
Thanh, T
The, H
Nguyen, T
Lan, N
Parry, C
Chau, N
Thwaites, G
Thanh, D
Baker, S
author_sort Thompson, C
collection OXFORD
description <br xmlns:etd="http://www.ouls.ox.ac.uk/ora/modsextensions"><strong>Objectives: </strong>We aimed to quantify the impact of fluoroquinolone resistance on the clinical outcome of paediatric shigellosis patients treated with fluoroquinolones in southern Vietnam. Such information is important to inform therapeutic management for infections caused by this increasingly drug-resistant pathogen, responsible for high morbidity and mortality in young children globally.</br><br xmlns:etd="http://www.ouls.ox.ac.uk/ora/modsextensions"><strong>Methods: </strong>Clinical information and bacterial isolates were derived from a randomized controlled trial comparing gatifloxacin with ciprofloxacin for the treatment of paediatric shigellosis. Time–kill experiments were performed to evaluate the impact of MIC on the in vitro growth of Shigella and Cox regression modelling was used to compare clinical outcome between treatments and Shigella species.</br><br xmlns:etd="http://www.ouls.ox.ac.uk/ora/modsextensions"><strong>Results: </strong>Shigella flexneri patients treated with gatifloxacin had significantly worse outcomes than those treated with ciprofloxacin. However, the MICs of fluoroquinolones were not significantly associated with poorer outcome. The presence of S83L and A87T mutations in the gyrA gene significantly increased MICs of fluoroquinolones. Finally, elevated MICs and the presence of the qnrS gene allowed Shigella to replicate efficiently in vitro in high concentrations of ciprofloxacin.</br><br xmlns:etd="http://www.ouls.ox.ac.uk/ora/modsextensions"><strong>Conclusions: </strong>We found that below the CLSI breakpoint, there was no association between MIC and clinical outcome in paediatric shigellosis infections. However, S. flexneri patients had worse clinical outcomes when treated with gatifloxacin in this study regardless of MIC. Additionally, Shigella harbouring the qnrS gene are able to replicate efficiently in high concentrations of ciprofloxacin and we hypothesize that such strains possess a competitive advantage against fluoroquinolone-susceptible strains due to enhanced shedding and transmission.</br>
first_indexed 2024-03-06T21:51:46Z
format Journal article
id oxford-uuid:4b845c4a-21af-4fe1-84f5-5488d02b6a37
institution University of Oxford
language English
last_indexed 2024-03-06T21:51:46Z
publishDate 2015
publisher Oxford University Press
record_format dspace
spelling oxford-uuid:4b845c4a-21af-4fe1-84f5-5488d02b6a372022-03-26T15:44:09ZClinical implications of reduced susceptibility to fluoroquinolones in paediatric Shigella sonnei and Shigella flexneri infectionsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:4b845c4a-21af-4fe1-84f5-5488d02b6a37EnglishSymplectic Elements at OxfordOxford University Press2015Thompson, CThieu, NVinh, PDuc, AWolbers, MVinh, HCampbell, JNgoc, DHoang, NThanh, TThe, HNguyen, TLan, NParry, CChau, NThwaites, GThanh, DBaker, S<br xmlns:etd="http://www.ouls.ox.ac.uk/ora/modsextensions"><strong>Objectives: </strong>We aimed to quantify the impact of fluoroquinolone resistance on the clinical outcome of paediatric shigellosis patients treated with fluoroquinolones in southern Vietnam. Such information is important to inform therapeutic management for infections caused by this increasingly drug-resistant pathogen, responsible for high morbidity and mortality in young children globally.</br><br xmlns:etd="http://www.ouls.ox.ac.uk/ora/modsextensions"><strong>Methods: </strong>Clinical information and bacterial isolates were derived from a randomized controlled trial comparing gatifloxacin with ciprofloxacin for the treatment of paediatric shigellosis. Time–kill experiments were performed to evaluate the impact of MIC on the in vitro growth of Shigella and Cox regression modelling was used to compare clinical outcome between treatments and Shigella species.</br><br xmlns:etd="http://www.ouls.ox.ac.uk/ora/modsextensions"><strong>Results: </strong>Shigella flexneri patients treated with gatifloxacin had significantly worse outcomes than those treated with ciprofloxacin. However, the MICs of fluoroquinolones were not significantly associated with poorer outcome. The presence of S83L and A87T mutations in the gyrA gene significantly increased MICs of fluoroquinolones. Finally, elevated MICs and the presence of the qnrS gene allowed Shigella to replicate efficiently in vitro in high concentrations of ciprofloxacin.</br><br xmlns:etd="http://www.ouls.ox.ac.uk/ora/modsextensions"><strong>Conclusions: </strong>We found that below the CLSI breakpoint, there was no association between MIC and clinical outcome in paediatric shigellosis infections. However, S. flexneri patients had worse clinical outcomes when treated with gatifloxacin in this study regardless of MIC. Additionally, Shigella harbouring the qnrS gene are able to replicate efficiently in high concentrations of ciprofloxacin and we hypothesize that such strains possess a competitive advantage against fluoroquinolone-susceptible strains due to enhanced shedding and transmission.</br>
spellingShingle Thompson, C
Thieu, N
Vinh, P
Duc, A
Wolbers, M
Vinh, H
Campbell, J
Ngoc, D
Hoang, N
Thanh, T
The, H
Nguyen, T
Lan, N
Parry, C
Chau, N
Thwaites, G
Thanh, D
Baker, S
Clinical implications of reduced susceptibility to fluoroquinolones in paediatric Shigella sonnei and Shigella flexneri infections
title Clinical implications of reduced susceptibility to fluoroquinolones in paediatric Shigella sonnei and Shigella flexneri infections
title_full Clinical implications of reduced susceptibility to fluoroquinolones in paediatric Shigella sonnei and Shigella flexneri infections
title_fullStr Clinical implications of reduced susceptibility to fluoroquinolones in paediatric Shigella sonnei and Shigella flexneri infections
title_full_unstemmed Clinical implications of reduced susceptibility to fluoroquinolones in paediatric Shigella sonnei and Shigella flexneri infections
title_short Clinical implications of reduced susceptibility to fluoroquinolones in paediatric Shigella sonnei and Shigella flexneri infections
title_sort clinical implications of reduced susceptibility to fluoroquinolones in paediatric shigella sonnei and shigella flexneri infections
work_keys_str_mv AT thompsonc clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT thieun clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT vinhp clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT duca clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT wolbersm clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT vinhh clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT campbellj clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT ngocd clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT hoangn clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT thanht clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT theh clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT nguyent clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT lann clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT parryc clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT chaun clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT thwaitesg clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT thanhd clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections
AT bakers clinicalimplicationsofreducedsusceptibilitytofluoroquinolonesinpaediatricshigellasonneiandshigellaflexneriinfections