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Solomon S, Akeju O, Odumade OA, Ambachew R, Gebreyohannes Z, Van Wickle K, Abayneh M, Metaferia G, Carvalho MJ, Thomson K, Sands K, Walsh TR, Milton R, Goddard FGB, Bekele D, Chan GJ. Prevalence and risk factors for antimicrobial resistance among newborns with gram-negative sepsis. PLoS One 2021; 16:e0255410. [PMID: 34343185 PMCID: PMC8330902 DOI: 10.1371/journal.pone.0255410] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 07/16/2021] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Newborn sepsis accounts for more than a third of neonatal deaths globally and one in five neonatal deaths in Ethiopia. The first-line treatment recommended by WHO is the combination of gentamicin with ampicillin or benzylpenicillin. Gram-negative bacteria (GNB) are increasingly resistant to previously effective antibiotics. OBJECTIVES Our goal was to estimate the prevalence of antibiotic-resistant gram-negative bacteremia and identify risk factors for antibiotic resistance, among newborns with GNB sepsis. METHODS At a tertiary hospital in Ethiopia, we enrolled a cohort pregnant women and their newborns, between March and December 2017. Newborns who were followed up until 60 days of life for clinical signs of sepsis. Among the newborns with clinical signs of sepsis, blood samples were cultured; bacterial species were identified and tested for antibiotic susceptibility. We described the prevalence of antibiotic resistance, identified newborn, maternal, and environmental factors associated with multidrug resistance (MDR), and combined resistance to ampicillin and gentamicin (AmpGen), using multivariable regression. RESULTS Of the 119 newborns with gram-negative bacteremia, 80 (67%) were born preterm and 82 (70%) had early-onset sepsis. The most prevalent gram-negative species were Klebsiella pneumoniae 94 (79%) followed by Escherichia coli 10 (8%). Ampicillin resistance was found in 113 cases (95%), cefotaxime 104 (87%), gentamicin 101 (85%), AmpGen 101 (85%), piperacillin-tazobactam 47 (39%), amikacin 10 (8.4%), and Imipenem 1 (0.8%). Prevalence of MDR was 88% (n = 105). Low birthweight and late-onset sepsis (LOS) were associated with higher risks of AmpGen-resistant infections. All-cause mortality was higher among newborns treated with ineffective antibiotics. CONCLUSION There was significant resistance to current first-line antibiotics and cephalosporins. Additional data are needed from primary care and community settings. Amikacin and piperacillin-tazobactam had lower rates of resistance; however, context-specific assessments of their potential adverse effects, their local availability, and cost-effectiveness would be necessary before selecting a new first-line regimen to help guide clinical decision-making.
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Yu Y, Andrey DO, Yang RS, Sands K, Tansawai U, Li M, Portal E, Gales AC, Niumsup PR, Sun J, Liao X, Liu YH, Walsh TR. A Klebsiella pneumoniae strain co-harbouring mcr-1 and mcr-3 from a human in Thailand. J Antimicrob Chemother 2021; 75:2372-2374. [PMID: 32294160 DOI: 10.1093/jac/dkaa133] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Andrey DO, Pereira Dantas P, Martins WBS, Marques De Carvalho F, Almeida LGP, Sands K, Portal E, Sauser J, Cayô R, Nicolas MF, Vasconcelos ATR, Medeiros EA, Walsh TR, Gales AC. An Emerging Clone, Klebsiellapneumoniae Carbapenemase 2-Producing K. pneumoniae Sequence Type 16, Associated With High Mortality Rates in a CC258-Endemic Setting. Clin Infect Dis 2021; 71:e141-e150. [PMID: 31712802 PMCID: PMC7583420 DOI: 10.1093/cid/ciz1095] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 11/09/2019] [Indexed: 12/15/2022] Open
Abstract
Background Carbapenemase-producing Klebsiella pneumoniae has become a global priority, not least in low- and middle-income countries. Here, we report the emergence and clinical impact of a novel Klebsiella pneumoniae carbapenemase–producing K. pneumoniae (KPC-KP) sequence type (ST) 16 clone in a clonal complex (CC) 258–endemic setting. Methods In a teaching Brazilian hospital, a retrospective cohort of adult KPC-KP bloodstream infection (BSI) cases (January 2014 to December 2016) was established to study the molecular epidemiology and its impact on outcome (30-day all-cause mortality). KPC-KP isolates underwent multilocus sequence typing. Survival analysis between ST/CC groups and risk factors for fatal outcome (logistic regression) were evaluated. Representative isolates underwent whole-genome sequencing and had their virulence tested in a Galleria larvae model. Results One hundred sixty-five unique KPC-KP BSI cases were identified. CC258 was predominant (66%), followed by ST16 (12%). The overall 30-day mortality rate was 60%; in contrast, 95% of ST16 cases were fatal. Patients’ severity scores were high and baseline clinical variables were not statistically different across STs. In multivariate analysis, ST16 (odds ratio [OR], 21.4; 95% confidence interval [CI], 2.3–202.8; P = .008) and septic shock (OR, 11.9; 95% CI, 4.2–34.1; P < .001) were independent risk factors for fatal outcome. The ST16 clone carried up to 14 resistance genes, including blaKPC-2 in an IncFIBpQIL plasmid, KL51 capsule, and yersiniabactin virulence determinants. The ST16 clone was highly pathogenic in the larvae model. Conclusions Mortality rates were high in this KPC-KP BSI cohort, where CC258 is endemic. An emerging ST16 clone was associated with high mortality. Our results suggest that even in endemic settings, highly virulent clones can rapidly emerge demanding constant monitoring.
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Portal E, Sands K, Portnojs A, Chalker VJ, Spiller OB. Legionella antimicrobial sensitivity testing: comparison of microbroth dilution with BCYE and LASARUS solid media. J Antimicrob Chemother 2021; 76:1197-1204. [PMID: 33367732 PMCID: PMC8050766 DOI: 10.1093/jac/dkaa535] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 11/20/2020] [Indexed: 01/11/2023] Open
Abstract
OBJECTIVES There is a lack of international unification for AST methodology for Legionella pneumophila. Current literature contains multiple possible methods and this study compares each of them to determine methodological concordance. METHODS Antibiotic susceptibility of 50 L. pneumophila strains was determined using broth microdilution (BMD), serial antimicrobial dilution in traditional buffered charcoal yeast extract (BCYE) agar (as well as comparison with gradient strip overlay on BCYE) and in a novel charcoal-free agar (LASARUS) for rifampicin, azithromycin, levofloxacin and doxycycline. RESULTS The deviation of tested media relative to BMD highlighted the overall similarity of BMD and LASARUS across all antimicrobials tested (within one serial dilution). BCYE agar dilution showed an increased MIC of up to five serial dilutions relative to BMD, while MICs by gradient strip overlay on BCYE were elevated by two to three serial dilutions, with the exception of doxycycline, which was decreased by three serial dilutions relative to MIC values determined by BMD. The MIC range for azithromycin was wider than for other antimicrobials tested and found to be caused by the presence or absence of the lpeAB gene. CONCLUSIONS BMD-based antimicrobial susceptibility testing (AST) methodology should be the internationally agreed gold standard for Legionella spp. AST, as is common for other bacterial species. Traditional BCYE gave significantly elevated MIC results and its use should be discontinued for Legionella spp., while MIC determination using LASARUS solid medium gave results concordant (within one serial dilution) with BMD for all antimicrobials tested. To the best of our knowledge, this study is the first to identify the lpeAB gene in UK isolates.
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Sands K, Carvalho MJ, Portal E, Thomson K, Dyer C, Akpulu C, Andrews R, Ferreira A, Gillespie D, Hender T, Hood K, Mathias J, Milton R, Nieto M, Taiyari K, Chan GJ, Bekele D, Solomon S, Basu S, Chattopadhyay P, Mukherjee S, Iregbu K, Modibbo F, Uwaezuoke S, Zahra R, Shirazi H, Muhammad A, Mazarati JB, Rucogoza A, Gaju L, Mehtar S, Bulabula ANH, Whitelaw A, Walsh TR. Characterization of antimicrobial-resistant Gram-negative bacteria that cause neonatal sepsis in seven low- and middle-income countries. Nat Microbiol 2021; 6:512-523. [PMID: 33782558 PMCID: PMC8007471 DOI: 10.1038/s41564-021-00870-7] [Citation(s) in RCA: 115] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 01/22/2021] [Indexed: 01/31/2023]
Abstract
Antimicrobial resistance in neonatal sepsis is rising, yet mechanisms of resistance that often spread between species via mobile genetic elements, ultimately limiting treatments in low- and middle-income countries (LMICs), are poorly characterized. The Burden of Antibiotic Resistance in Neonates from Developing Societies (BARNARDS) network was initiated to characterize the cause and burden of antimicrobial resistance in neonatal sepsis for seven LMICs in Africa and South Asia. A total of 36,285 neonates were enrolled in the BARNARDS study between November 2015 and December 2017, of whom 2,483 were diagnosed with culture-confirmed sepsis. Klebsiella pneumoniae (n = 258) was the main cause of neonatal sepsis, with Serratia marcescens (n = 151), Klebsiella michiganensis (n = 117), Escherichia coli (n = 75) and Enterobacter cloacae complex (n = 57) also detected. We present whole-genome sequencing, antimicrobial susceptibility and clinical data for 916 out of 1,038 neonatal sepsis isolates (97 isolates were not recovered from initial isolation at local sites). Enterobacterales (K. pneumoniae, E. coli and E. cloacae) harboured multiple cephalosporin and carbapenem resistance genes. All isolated pathogens were resistant to multiple antibiotic classes, including those used to treat neonatal sepsis. Intraspecies diversity of K. pneumoniae and E. coli indicated that multiple antibiotic-resistant lineages cause neonatal sepsis. Our results will underpin research towards better treatments for neonatal sepsis in LMICs.
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Tansawai U, Yu Y, Kiddee A, Assawatheptawee K, Sands K, Hassan B, Walsh TR, Niumsup PR. Emergence of mcr-3-mediated IncP and IncFII plasmids in Thailand. J Glob Antimicrob Resist 2021; 24:446-447. [PMID: 33618040 DOI: 10.1016/j.jgar.2021.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 01/19/2021] [Accepted: 02/05/2021] [Indexed: 11/18/2022] Open
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Mentasti M, David S, Sands K, Khan S, Davies L, Turner L, Wootton M. Rapid detection and differentiation of mobile colistin resistance (mcr-1 to mcr-10) genes by real-time PCR and melt-curve analysis. J Hosp Infect 2021; 110:148-155. [PMID: 33485969 DOI: 10.1016/j.jhin.2021.01.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/13/2021] [Accepted: 01/13/2021] [Indexed: 10/22/2022]
Abstract
BACKGROUND The emergence of multi-drug-resistant (MDR) micro-organisms prompted new interest in older antibiotics, such as colistin, that had been abandoned previously due to limited efficacy or high toxicity. Over the years, several chromosomal-encoded colistin resistance mechanisms have been described; more recently, 10 plasmid-mediated mobile colistin resistance (mcr) genes have been identified. Spread of these genes among MDR Gram-negative bacteria is a matter of serious concern; therefore, reliable and timely mcr detection is paramount. AIM To design and validate a multiplex real-time polymerase chain reaction (PCR) assay for detection and differentiation of mcr genes. METHODS All available mcr alleles were downloaded from the National Center for Biotechnology Information Reference Gene Catalogue, aligned with Clustal Omega and primers designed using Primer-BLAST. Real-time PCR monoplexes were optimized and validated using a panel of 120 characterized Gram-negative strains carrying a wide range of resistance genes, often in combination. Melt-curve analysis was used to confirm positive results. FINDINGS In-silico analysis enabled the design of a 'screening' assay for detection of mcr-1/2/6, mcr-3, mcr-4, mcr-5, mcr-7, mcr-8 and mcr-9/10, paired with an internal control assay to discount inhibition. A 'supplementary' assay was subsequently designed to differentiate mcr-1, mcr-2, mcr-6, mcr-9 and mcr-10. Expected results were obtained for all strains (100% sensitivity and specificity). Melt-curve analysis showed consistent melting temperature results. Inhibition was not observed. CONCLUSIONS The assay is rapid and easy to perform, enabling unequivocal mcr detection and differentiation even when more than one variant is present. Adoption by clinical and veterinary microbiology laboratories would aid the surveillance of mcr genes amongst Gram-negative bacteria.
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Roch M, Sierra R, Sands K, Martins WMBS, Schrenzel J, Walsh TR, Gales AC, Andrey DO. Vertical and horizontal dissemination of an IncC plasmid harbouring rmtB 16S rRNA methylase gene, conferring resistance to plazomicin, among invasive ST258 and ST16 KPC-producing Klebsiella pneumoniae. J Glob Antimicrob Resist 2020; 24:183-189. [PMID: 33373732 DOI: 10.1016/j.jgar.2020.12.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 11/13/2020] [Accepted: 12/06/2020] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVES Carbapenem resistance in Klebsiella pneumoniae is a major clinical challenge. Aminoglycosides remain an important asset in the current therapeutic arsenal to treat these infections. We examined aminoglycoside resistance phenotypes and genomics in a collection of 100 invasive KPC-producing K. pneumoniae isolates sequentially collected in a Brazilian tertiary hospital between 2014 and 2016. METHODS Aminoglycoside susceptibility testing was performed. We used a combined long-read (MinION) and short-read (Illumina) whole-genome sequencing strategy to provide a genomic picture of aminoglycoside resistance genes, with particular emphasis on 16S rRNA methyltransferases and related plasmids. RESULTS 68% of the strains were resistant to gentamicin and 42% to amikacin, with 35% resistant to both of these commonly used aminoglycosides. We identified the 16S rRNA methyltransferase gene rmtB in 30% of these isolates: 97% (29/30) belonged to sequence type 258 (ST258) and a single isolate to the emergent ST16 clone. In ST258 and ST16 the rmtB gene was located on large IncC plasmids of 177 kb and 174 kb, respectively, highly similar to a plasmid previously identified in Proteus mirabilis in the same hospital. Moreover, 99% of the isolates remained susceptible to the veterinary-approved drug apramycin, currently under clinical development for human medicine. CONCLUSION Such findings in geographically and temporally related isolates suggest a combination of vertical clonal spread as well as horizontal interspecies and intraspecies plasmid transfer. This broad rmtB dissemination in an endemic setting for KPC-producing clones is worrisome since it provides resistance to most clinically available aminoglycosides, including the novel aminoglycoside-modifying enzyme-resistant plazomicin.
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Martins WMBS, Seco BMS, Sampaio JLM, Sands K, Toleman MA, Gales AC. Detection of BKC-1 in Citrobacter freundii: A clue to mobilisation in an IncQ1 plasmid carrying bla BKC-1. Int J Antimicrob Agents 2020; 56:106042. [PMID: 32479892 DOI: 10.1016/j.ijantimicag.2020.106042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 05/15/2020] [Accepted: 05/21/2020] [Indexed: 10/24/2022]
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Farzana R, Jones LS, Rahman MA, Sands K, Portal E, Boostrom I, Kalam MA, Hasan B, Khan A, Walsh TR. Molecular and epidemiological analysis of a Burkholderia cepacia sepsis outbreak from a tertiary care hospital in Bangladesh. PLoS Negl Trop Dis 2020; 14:e0008200. [PMID: 32271750 PMCID: PMC7173934 DOI: 10.1371/journal.pntd.0008200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 04/21/2020] [Accepted: 03/05/2020] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Burkholderia cepacia complex (Bcc) is a group of serious pathogens in cystic fibrosis patients and causes life threatening infections in immunocompromised patients. Species within the Bcc are widely distributed within the environment, can survive in the presence of disinfectants and antiseptics, and are inherently multidrug resistant (MDR). METHODS Dhaka Medical College Hospital (DMCH) patients with a B. cepacia positive blood culture between 20 October 2016 to 23rd September 2017 were considered as outbreak cases. Blood stream infections (BSIs) were detected using BacT/ALERT 3D at DMCH. B. cepacia was isolated on chromogenic UTI media followed by MALDI-TOF. Minimum inhibitory concentration (MIC) of clinically relevant antibiotics was determined by agar dilution. Whole genome sequencing was performed on an Illumina MiSeq platform. Patients' demographic and clinical data were collected. Patients' clinical history and genomic data of the outbreak strains were merged to investigate possible outbreaks. Ninety-one B. cepacia genomes were downloaded from 'Burkholderia Genome Database' and the genomic background of the global strains were compared with our outbreak strains. RESULTS Among 236 BSIs, 6.35% (15/236) were B. cepacia. Outbreak cases were confined to the burn critical care unit and, to a lesser extent, the paediatrics department. There was a continuum of overlapping cases at DMCH between 23 October 2016 to 30 August 2017. Core genome SNPs showed that the outbreak strains were confined to a single clade, corresponded to a common clone (ST1578). The strains were shown to be MDR and associated with a mortality of 31% excluding discharge against medical advice. MIC profiles of the strains suggested that antibiotics deployed as empirical therapy were invariably inappropriate. The genetic background of the outbreak strains was very similar; however, a few variations were found regarding the presence of virulence genes. Compared to global strains from the Burkholderia Genome Database, the Bangladeshi strains were genetically distinct. CONCLUSIONS Environmental surveillance is required to investigate the aetiology and mode of transmission of the B. cepacia outbreak. Systematic management of nosocomial outbreaks, particularly in resource limited regions, will mitigate transmission and will improve patients' outcomes.
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Naha S, Sands K, Mukherjee S, Roy C, Rameez MJ, Saha B, Dutta S, Walsh TR, Basu S. KPC-2-producing Klebsiella pneumoniae ST147 in a neonatal unit: Clonal isolates with differences in colistin susceptibility attributed to AcrAB-TolC pump. Int J Antimicrob Agents 2020; 55:105903. [PMID: 31954832 DOI: 10.1016/j.ijantimicag.2020.105903] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 01/08/2020] [Accepted: 01/11/2020] [Indexed: 01/21/2023]
Abstract
This study characterizes four KPC-2-producing Klebsiella pneumoniae isolates from neonates belonging to a single sequence type 147 (ST147) in relation to carbapenem resistance and explores probable mechanisms of differential colistin resistance among the clonal cluster. Whole genome sequencing (WGS) revealed that the isolates were nearly 100% identical and harbored resistance genes (blaKPC-2,OXA-9,CTX-M-15,SHV-11,OXA-1,TEM-1B, oqxA, oqxB, qnrB1, fosA, arr-2, sul1, aacA4, aac(6')Ib-cr, aac(6')Ib), and several virulence genes. blaKPC-2 was the only carbapenem-resistant gene found, bracketed between ISKpn7 and ISKpn6 of Tn4401b on a non-conjugative IncFII plasmid. Remarkably, one of the clonal isolates was resistant to colistin, the mechanistic basis of which was not apparent from comparative genomics. The transmissible colistin resistance gene, mcr, was absent. Efflux pump inhibitor, carbonyl cyanide 3-chlorophenylhydrazone (CCCP) rendered a 32-fold decrease in the minimum inhibitory concentration (MIC) of colistin in the resistant isolate only. acrB, tolC, ramA, and soxS genes of the AcrAB-TolC pump system overexpressed exclusively in the colistin-resistant isolate, although the corresponding homologs of the AcrAB-TolC pump, regulators and promoters were mutually identical. No change was observed in the expression of other efflux genes (kpnE/F and kpnG/H) or two-component system (TCS) genes (phoP/phoQ, pmrA/pmrB). Colistin resistance in one of the clonal KPC-2-producing isolates is postulated to be due to overexpression of the AcrAB-TolC pump. This study is probably the first to report clinical clonal K. pneumoniae isolates with differences in colistin susceptibility. The presence of carbapenem-resistant isolates with differential behavior in the expression of a genomically identical pump system indicates the nuances of the resistance mechanisms and the difficulty of treatment thereof.
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Lim SY, Dafydd M, Ong J, Ord-McDermott LA, Board-Davies E, Sands K, Williams D, Sloan AJ, Heard CM. Mucoadhesive thin films for the simultaneous delivery of microbicide and anti-inflammatory drugs in the treatment of periodontal diseases. Int J Pharm 2020; 573:118860. [DOI: 10.1016/j.ijpharm.2019.118860] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/04/2019] [Accepted: 11/06/2019] [Indexed: 12/19/2022]
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Farzana R, Jones LS, Rahman MA, Toleman MA, Sands K, Portal E, Boostrom I, Kalam MA, Hassan B, Uddin AKMN, Walsh TR. Emergence of mcr-1 mediated colistin resistant Escherichia coli from a hospitalized patient in Bangladesh. J Infect Dev Ctries 2019; 13:773-776. [DOI: 10.3855/jidc.11541] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 07/24/2019] [Indexed: 10/31/2022] Open
Abstract
Introduction: The emergence of plasmid mediated mcr in bacteria has become global public health threat. Herein, we report a mcr-1 positive E. coli in normal human flora from a patient admitted in Dhaka Medical College Hospital (DMCH).
Methodology: In total, 700 non-duplicate rectal swabs were collected from DMCH during 13th May to 12th June 2018. E. coli from rectal swabs were isolated on chromogenic UTI media containing vancomycin 10mg/l (Liofilchem, Italy) and confirmed by MALDI-TOF. Minimum inhibitory concentrations (MIC) were determined by agar dilution and interpreted according to EUCAST breakpoints. Genomic analysis of mcr positive E. coli (MCRPEC) was performed by Illumina MiSeq sequencing and pulsed field gel electrophoresis (PFGE) using S1 nuclease DNA digests and blamcr-1 probing. Transferability of blamcr-1 were determined by conjugation assays.
Results: We found one MCRPEC from 700 rectal swab screening which was isolated from the rectal swab culture of a 17-year boy who was admitted to the burns ICU, DMCH with 53% flame burn involving much of the trunk and face. Genome sequencing revealed that mcr-1 was present on an IncH12 plasmid of 257,243 bp and flanked by ISApaI1. The colistin resistance can be transferred to the recipient Klebsiella varricola with a frequency of 8.3 × 10-5. Transconjugants were more resistant to colistin than donor (MIC 32 µg/mL).
Conclusions: This is the first human associated mcr in Bangladesh. These data indicate the need for a systematic “one health” surveillance in the country.
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Mentasti M, Prime K, Sands K, Khan S, Wootton M. Rapid detection of IMP, NDM, VIM, KPC and OXA-48-like carbapenemases from Enterobacteriales and Gram-negative non-fermenter bacteria by real-time PCR and melt-curve analysis. Eur J Clin Microbiol Infect Dis 2019; 38:2029-2036. [DOI: 10.1007/s10096-019-03637-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/10/2019] [Indexed: 10/26/2022]
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Yang QE, Tansawai U, Andrey DO, Wang S, Wang Y, Sands K, Kiddee A, Assawatheptawee K, Bunchu N, Hassan B, Walsh TR, Niumsup PR. Environmental dissemination of mcr-1 positive Enterobacteriaceae by Chrysomya spp. (common blowfly): An increasing public health risk. ENVIRONMENT INTERNATIONAL 2019; 122:281-290. [PMID: 30455105 DOI: 10.1016/j.envint.2018.11.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/08/2018] [Accepted: 11/09/2018] [Indexed: 06/09/2023]
Abstract
Until recently, the role of insects, and particularly flies, in disseminating antimicrobial resistance (AMR) has been poorly studied. In this study, we screened blowflies (Chrysomya spp.) from different areas near the city of Phitsanulok, Northern Thailand, for the presence of AMR genes and in particular, mcr-1, using whole genome sequencing (WGS). In total, 48 mcr-1-positive isolates were recovered, consisting of 17 mcr-1-positive Klebsiella pneumoniae (MCRPKP) and 31 mcr-1-positive Escherichia coli (MCRPEC) strains. The 17 MCRPKP were shown to be clonal (ST43) with few single poly nucleomorphs (SNPs) by WGS analysis. In in-vitro models, the MCRPKP were shown to be highly virulent. In contrast, 31 recovered MCRPEC isolates are varied, belonging to 12 different sequence types shared with those causing human infections. The majority of mcr-1 gene are located on IncX4 plasmids (29/48, 60.42%), sharing an identical plasmid backbone. These findings highlight the contribution of flies to the AMR contagion picture in low- and middle-income countries and the challenges of tackling global AMR.
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Farzana R, Jones LS, Rahman MA, Andrey DO, Sands K, Portal E, Watkins WJ, Pervin M, Banerjee M, Walsh TR. Outbreak of Hypervirulent Multidrug-resistant Klebsiella variicola Causing High Mortality in Neonates in Bangladesh. Clin Infect Dis 2018; 68:1225-1227. [DOI: 10.1093/cid/ciy778] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 09/06/2018] [Indexed: 12/18/2022] Open
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Yang Q, Li M, Spiller OB, Andrey DO, Hinchliffe P, Li H, MacLean C, Niumsup P, Powell L, Pritchard M, Papkou A, Shen Y, Portal E, Sands K, Spencer J, Tansawai U, Thomas D, Wang S, Wang Y, Shen J, Walsh T. Balancing mcr-1 expression and bacterial survival is a delicate equilibrium between essential cellular defence mechanisms. Nat Commun 2017; 8:2054. [PMID: 29233990 PMCID: PMC5727292 DOI: 10.1038/s41467-017-02149-0] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 11/09/2017] [Indexed: 12/20/2022] Open
Abstract
MCR-1 is a lipid A modifying enzyme that confers resistance to the antibiotic colistin. Here, we analyse the impact of MCR-1 expression on E. coli morphology, fitness, competitiveness, immune stimulation and virulence. Increased expression of mcr-1 results in decreased growth rate, cell viability, competitive ability and significant degradation in cell membrane and cytoplasmic structures, compared to expression of catalytically inactive MCR-1 (E246A) or MCR-1 soluble component. Lipopolysaccharide (LPS) extracted from mcr-1 strains induces lower production of IL-6 and TNF, when compared to control LPS. Compared to their parent strains, high-level colistin resistance mutants (HLCRMs) show reduced fitness (relative fitness is 0.41-0.78) and highly attenuated virulence in a Galleria mellonella infection model. Furthermore, HLCRMs are more susceptible to most antibiotics than their respective parent strains. Our results show that the bacterium is challenged to find a delicate equilibrium between expression of MCR-1-mediated colistin resistance and minimalizing toxicity and thus ensuring cell survival.
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Ellis AR, Fahie-Wilson M, Axcell M, Sands K, Hill RP. Macroprolactin(s): composition and reactivity in immunoassays and laboratory interpretation of results of an unusual patient serum. Ann Clin Biochem 2016; 43:57-62. [PMID: 16390610 DOI: 10.1258/000456306775141830] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background: Macroprolactin is a high molecular mass complex of prolactin that may be the cause of elevated serum prolactin as determined by immunoassay. The composition of macroprolactin and its reactivity in immunoassays are variable but the complex has minimal bioactivity in vivo. Hyperprolactinaemia due to unrecognized macroprolactinaemia can lead to misdiagnosis and mistreatment. Methods: Serum from a patient with an unusual pattern of immunoreactivity was distributed to three users of each of the most popular immunoassays represented in the UK National External Quality Assessment Scheme (NEQAS) for prolactin. Clinical details were provided and participating centres were invited to investigate the prolactin content of the specimen according to their local protocol, and to comment on their results. The nature of the macroprolactin in the specimen was investigated in detail by gel filtration chromatography of the native serum and of the serum after adsorption of IgG with protein A, and by affinity chromatography with concanavalin A. Results: Gel filtration studies revealed two peaks of macroprolactin in this serum. These macroprolactins were shown to be different in their IgG content and degree of glycosylation. All eight immunoassays reacted strongly with the macroprolactin present. The majority (78%) of centres that interpreted their results either demonstrated the presence of macroprolactin in the specimen, or suggested it as a likely cause of the hyperprolactinaemia. However, two centres inappropriately excluded macroprolactinaemia as the cause of the elevated prolactin, and a further two did not consider it at all. Data from previous UK NEQAS distributions (between 1996 and 2003) of macroprolactin containing sera are presented which suggest that the frequency of recognition of macroprolactin as a possible cause of hyperprolactinaemia has increased over time. Conclusions: Very high molecular mass forms of prolactin and the presence of multiple molecular mass forms, as detected in the case presented here, are uncommon. Also, the pattern of immunoreactivity reported in this specimen was unusual as most macroprolactins studied previously react less strongly in, for example, the Bayer ADVIA Centaur assay compared to the Roche E170 assay. Both peaks of macroprolactin in this serum reacted in all assays tested. This case highlights the variable nature and immunoreactive behaviour of macroprolactin species.
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Sands K, Jansen R, Zaslau S, Greenwald D. Review article: the safety of therapeutic drugs in male inflammatory bowel disease patients wishing to conceive. Aliment Pharmacol Ther 2015; 41:821-34. [PMID: 25752753 DOI: 10.1111/apt.13142] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 04/27/2013] [Accepted: 02/05/2015] [Indexed: 12/20/2022]
Abstract
BACKGROUND Many therapeutic drugs are used by patients with inflammatory bowel disease, often around the time of conception. The pregnancy outcomes of males and females exposed to these therapeutics needs to be examined and this information is necessary to counsel patients appropriately. AIM To review the literature describing male infertility and inflammatory bowel disease to educate practitioners of the impact of inflammatory bowel disease on male reproduction and the impact of therapeutics on pregnancy outcomes. METHODS We performed a PubMed search using the search terms 'male infertility,' 'Crohn's disease,' 'inflammatory bowel disease,' 'ulcerative colitis,' 'ciprofloxacin AND infertility,' 'metronidazole AND infertility,' 'sulfasalazine AND infertility,' 'azathioprine AND infertility,' 'methotrexate AND infertility,' 'ciclosporin AND infertility,' 'corticosteroids AND infertility,' 'infliximab AND male fertility,' 'infliximab AND infertility,' 'infliximab AND foetus,' 'infliximab AND paternal exposure' and 'infliximab AND sperm.' References from selected papers were reviewed and used if relevant. RESULTS Over half of male patients with IBD have some degree of infertility, compared to 8-17% of the general population. Semen parameters including total count, motility and morphology may be adversely affected by therapeutics. IBD medications in males do not increase foetal risk with the possible exception of azathioprine and mercaptopurine; however, increased foetal risk is seen in other drugs if taken by female patients. CONCLUSIONS It is recognised that male infertility is often impacted with therapeutic drugs used to treat inflammatory bowel disease; however, the effects of the paternal drug exposure at the time of conception and exposure in utero should be considered to counsel patients appropriately.
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Sands K, Williams DW, Wilson M, Lewis M, Wise MP. The Dynamics of Polymicrobial Biofilms. Am J Respir Crit Care Med 2013; 188:1266. [DOI: 10.1164/rccm.201305-0916le] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Grossman S, Lieberman R, Bar J, Fischer C, Lipsitz L, Mottley L, Sands K, Zimetbaum P, Shapiro N. Reducing Admissions Utilizing the Boston Syncope Criteria. Acad Emerg Med 2007. [DOI: 10.1197/j.aem.2007.03.824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Grossman SA, Fischer C, Bar JL, Lipsitz LA, Mottley L, Sands K, Thompson S, Zimetbaum P, Shapiro NI. The yield of head CT in syncope: a pilot study. Intern Emerg Med 2007; 2:46-9. [PMID: 17551685 PMCID: PMC2780634 DOI: 10.1007/s11739-007-0010-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2006] [Accepted: 01/04/2007] [Indexed: 11/29/2022]
Abstract
UNLABELLED Although head CT is often routinely performed in emergency department (ED) patients with syncope, few studies have assessed its value. OBJECTIVES To determine the yield of routine head CT in ED patients with syncope and analyse the factors associated with a positive CT. METHODS Prospective, observational, cohort study of consecutive patients presenting with syncope to an urban tertiary-care ED (48,000 annual visits). INCLUSION CRITERIA age >or=18 and loss of consciousness (LOC). Exclusion criteria included persistent altered mental status, drug-related or post-trauma LOC, seizure or hypoglycaemia. Primary outcome was abnormal head CT including subarachnoid, subdural or parenchymal haemorrhage, infarction, signs of acute stroke and newly diagnosed brain mass. RESULTS Of 293 eligible patients, 113 (39%) underwent head CT and comprise the study cohort. Ninety-five patients (84%) were admitted to the hospital. Five patients, 5% (95% CI=0.8%-8%), had an abnormal head CT: 2 subarachnoid haemorrhage, 2 cerebral haemorrhage and 1 stroke. Post hoc examination of patients with an abnormal head CT revealed focal neurologic findings in 2 and a new headache in 1. The remaining 2 patients had no new neurologic findings but physical findings of trauma (head lacerations with periorbital ecchymoses suggestive of orbital fractures). All patients with positive findings on CT were >65 years of age. Of the 108 remaining patients who had head CT, 45 (32%-51%) had signs or symptoms of neurologic disease including headache, trauma above the clavicles or took coumadin. Limiting head CT to this population would potentially reduce scans by 56% (47%-65%). If age >60 were an additional criteria, scans would be reduced by 24% (16%-32%). Of the patients who did not have head CT, none were found to have new neurologic disease during hospitalisation or 30-day follow-up. CONCLUSIONS Our data suggest that the derivation of a prospectively derived decision rule has the potential to decrease the routine use of head CT in patients presenting to the ED with syncope.
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Avery R, Kalaycio M, Pohlman B, Sobecks R, Kuczkowski E, Andresen S, Mossad S, Shamp J, Curtis J, Kosar J, Sands K, Serafin M, Bolwell B. Early vancomycin-resistant enterococcus (VRE) bacteremia after allogeneic bone marrow transplantation is associated with a rapidly deteriorating clinical course. Bone Marrow Transplant 2005; 35:497-9. [PMID: 15640812 DOI: 10.1038/sj.bmt.1704821] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Vancomycin-resistant enterococcal (VRE) infection is a growing threat. We studied the incidence, risk factors, and clinical course of early-onset VRE bacteremia in allogeneic hematopoietic stem cell transplant recipients. We carried out a chart review of 281 allogeneic hematopoietic stem cell transplant recipients from 1997-2003, including preparative regimen, diagnosis, status of disease, graft-versus-host disease prophylaxis, antimicrobial therapy, and survival. VRE bacteremia developed in 12/281 (4.3%) recipients; 10 (3.6%) were within 21 days of transplant. Diagnoses were acute leukemia (7), NHL (2), and MDS (1). In all, 70% had refractory/relapsed disease; 30% were in remission. In total, 50% had circulating blasts. Nine of 10 had matched unrelated donors (7/9 with CD8+ T-cell depletion). The average time to positive VRE cultures was 15 days; average WBC was 0.05, and 80% had concomitant infections. Despite treatment, all patients died within 73 days of VRE bacteremia. Intra-abdominal complications were common. Causes of death included bacterial or fungal infection, multiorgan failure, VOD, ARDS, and relapse. A total of 60% of patients engrafted neutrophils, but none engrafted platelets. Early VRE bacteremia after allogeneic bone marrow transplant is associated with a rapidly deteriorating clinical course, although not always directly due to VRE. Early VRE may be a marker for the critical condition of these high-risk patients at the time of transplant.
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Segal R, Poznansky MC, Connors L, Sands K, Barlam T. Changing patterns of presentations of patients with HIV-related disease at a tertiary referral centre and its implications for physician training. Int J STD AIDS 2001; 12:453-9. [PMID: 11394981 DOI: 10.1258/0956462011923480] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Highly active antiretroviral therapy (HAART) has been shown to be highly effective in controlling HIV-related disease progression. Our objective was to determine whether HAART had altered the spectrum of HIV-related disease presentations at a tertiary medical referral centre and if a change in the clinical presentations of HIV-infected individuals to the hospital had impacted on physicians' training. A retrospective study which examined all admissions of HIV-infected patients identified between 1 October 1996 to 30 September 1998 using a hospital-designed computer database was undertaken at the Beth Israel Deaconess Medical Center (BIDMC) tertiary medical referral centre. All medical residents were surveyed in order to assess their knowledge of HIV-associated admissions and their confidence treating HIV-infected patients. There were significant changes in the admitting diagnosis for HIV-related illness between 1996 and 1998. Admissions for opportunistic infections (OIs) declined whereas admissions with bacterial infections increased significantly. Use of HAART remained stable between the 2 years of the study. Physicians' overestimated the use of HAART and only 8% of residents felt very comfortable taking care of an HIV-infected patient. In conclusion, the spectrum of presentations with HIV-related disease to a tertiary referral centre continues to change in the HAART era and impacts on physicians' experience of the management of HIV disease.
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Sands K. John Foxe: exorcist. HISTORY TODAY 2001; 51:37-43. [PMID: 18988361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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