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Konstantinovski M, van Geest C, Bruijning M, Kroon-de Keizer L, Wallinga J, van Burgel N, Veldkamp KE. Rate of nosocomial MRSA transmission evaluated via contact screening. Antimicrob Resist Infect Control 2024; 13:92. [PMID: 39192375 DOI: 10.1186/s13756-024-01448-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 08/05/2024] [Indexed: 08/29/2024] Open
Abstract
BACKGROUND The prevention of methicillin-resistant S. aureus (MRSA) transmission in the healthcare setting is a priority in Infection Control practices. A cornerstone of this policy is contact tracing of nosocomial contacts after an unexpected MRSA finding. The objective of this retrospective study was to quantify the rates of MRSA transmission in different clinical settings. METHODS This multi-centre study included MRSA contact screening results from two regional hospitals and one academic hospital. MRSA contact tracing investigations from 2000 until 2019 were reviewed and post-contact screening results were included of index patients with an MRSA-positive culture and their unprotected contacts. Available typing results were used to rule out incidental findings. RESULTS Of 27,377 contacts screened after MRSA exposure, 21,488 were Health Care Workers (HCW) and 4816 patients. Post-contact screening was initiated for a total of 774 index cases, the average number of screened contacts per index case was 35.7 (range 1 to 640). MRSA transmission was observed in 0.15% (41) of the contacts, 19 (0.09%) HCW and 22 (0.46%) patients. The number needed to screen to detect one MRSA transmission was 667. The highest risk of MRSA transmission occurred during patient-to-patient contacts, with transmission rates varying from 0.32 to 1.32% among the participating hospitals. No transmissions were detected in HCW (n=2834) in the outpatient setting, and the rate of transmissions among HCW contacts on the wards was 0.13% (19 of 15,874). Among 344 contacts of patients with contact precautions, no transmissions were detected. CONCLUSIONS Reconsidering current MRSA contact tracing practices may lead to a more targeted approach with a lower number needed to screen.
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Affiliation(s)
- Maria Konstantinovski
- Department of Medical Microbiology, Leiden University Medical Center, Leiden University, Leiden, The Netherlands.
- Department of Microbiology, Medical Laboratories, Reinier de Graaf Groep, Delft, The Netherlands.
| | - Crista van Geest
- Department of Microbiology, Haga Teaching Hospital, The Hague, The Netherlands
| | - Marguerite Bruijning
- Department of Medical Microbiology, Leiden University Medical Center, Leiden University, Leiden, The Netherlands
| | | | - Jacco Wallinga
- Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden, The Netherlands
- Center for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Nathalie van Burgel
- Department of Microbiology, Haga Teaching Hospital, The Hague, The Netherlands
| | - Karin-Ellen Veldkamp
- Department of Medical Microbiology, Leiden University Medical Center, Leiden University, Leiden, The Netherlands
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2
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Wang Y, Zhao X, Zhang M, Sun X, Bai J, Peng Y, Li S, Han D, Ren S, Wang J, Han T, Gao Y, Ning B, Gao Z. A fluorescent amplification strategy for high-sensitive detection of 17 β-estradiol based on EXPAR and HCR. Anal Chim Acta 2020; 1116:1-8. [PMID: 32389184 DOI: 10.1016/j.aca.2020.04.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 01/14/2023]
Abstract
Environmental endocrine disruptors in the environment and food, especially 17 β-estradiol (E2), are important factors affecting the growth and development of organisms. In this research, we constructed a fluorescence strategy for two-step amplification that combined two currently popular methods, exponential amplification reaction (EXPAR) and hybridization chain reaction (HCR). E2 competed with the complementary DNA (cDNA) to bind the aptamer modified on the magnetic beads. The free complementary strand in the supernatant was used as a trigger sequence to activate EXPAR, producing a large amount of short single-stranded DNA (ssDNA). The amplified ssDNA can trigger the second HCR amplification, producing many long double-stranded DNA (dsDNA) analogues. According to the principle of fluorescence resonance energy transfer, the carboxyfluorescein (FAM) signals in H1 and H2 hairpins were quenched by black hole quencher (BHQ-1). After the addition of E2 and initiation of amplification, the initially quenched fluorescent signal would be restored. This strategy with a detection limit of 0.37 pg mL-1 (S/N = 3) showed a good linear relationship in the range of 0.4-800 pg mL-1. In addition, the recovery rates of the method for milk and water samples were 98.55%-116.95% and 92.32%-107.00%, respectively. This is the first report of the combined detection of EXPAR and HCR, providing a reference for rapid and highly sensitive detection using multiple isothermal amplification methods.
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Affiliation(s)
- Yu Wang
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China
| | - Xudong Zhao
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China
| | - Man Zhang
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China; School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology. Shanghai, 200093, PR China
| | - Xuan Sun
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China; College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Jialei Bai
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China
| | - Yuan Peng
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China
| | - Shuang Li
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China
| | - Dianpeng Han
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China
| | - Shuyue Ren
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China
| | - Jiang Wang
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China
| | - Tie Han
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China
| | - Yifei Gao
- School of Chemistry, University of New South Wales, Sydney, Australia
| | - Baoan Ning
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China
| | - Zhixian Gao
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Environmental and Operational Medicine, Academy of Military Medical Science, Academy of Military Science, Tianjin, 300050, PR China.
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van de Groep K, Bos MP, Savelkoul PHM, Rubenjan A, Gazenbeek C, Melchers WJG, van der Poll T, Juffermans NP, Ong DSY, Bonten MJM, Cremer OL. Development and first evaluation of a novel multiplex real-time PCR on whole blood samples for rapid pathogen identification in critically ill patients with sepsis. Eur J Clin Microbiol Infect Dis 2018; 37:1333-1344. [PMID: 29700761 PMCID: PMC6015113 DOI: 10.1007/s10096-018-3255-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Accepted: 04/06/2018] [Indexed: 12/19/2022]
Abstract
Molecular tests may enable early adjustment of antimicrobial therapy and be complementary to blood culture (BC) which has imperfect sensitivity in critically ill patients. We evaluated a novel multiplex real-time PCR assay to diagnose bloodstream pathogens directly in whole blood samples (BSI-PCR). BSI-PCR included 11 species- and four genus-specific PCRs, a molecular Gram-stain PCR, and two antibiotic resistance markers. We collected 5 mL blood from critically ill patients simultaneously with clinically indicated BC. Microbial DNA was isolated using the Polaris method followed by automated DNA extraction. Sensitivity and specificity were calculated using BC as reference. BSI-PCR was evaluated in 347 BC-positive samples (representing up to 50 instances of each pathogen covered by the test) and 200 BC-negative samples. Bacterial species-specific PCR sensitivities ranged from 65 to 100%. Sensitivity was 26% for the Gram-positive PCR, 32% for the Gram-negative PCR, and ranged 0 to 7% for yeast PCRs. Yeast detection was improved to 40% in a smaller set-up. There was no overall association between BSI-PCR sensitivity and time-to-positivity of BC (which was highly variable), yet Ct-values were lower for true-positive versus false-positive PCR results. False-positive results were observed in 84 (4%) of the 2200 species-specific PCRs in 200 culture-negative samples, and ranged from 0 to 6% for generic PCRs. Sensitivity of BSI-PCR was promising for individual bacterial pathogens, but still insufficient for yeasts and generic PCRs. Further development of BSI-PCR will focus on improving sensitivity by increasing input volumes and on subsequent implementation as a bedside test.
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Affiliation(s)
- Kirsten van de Groep
- Department of Epidemiology, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands. .,Department of Intensive Care Medicine, University Medical Center Utrecht, Utrecht University, Room F06.149, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands.
| | | | - Paul H M Savelkoul
- Microbiome, Amsterdam, the Netherlands.,Department of Medical Microbiology & Infection Control, VU University Medical Center, Amsterdam, the Netherlands.,Department of Medical Microbiology, Maastricht University Medical Center, Maastricht, the Netherlands
| | | | | | - Willem J G Melchers
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Tom van der Poll
- Center of Experimental and Molecular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.,Division of Infectious Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Nicole P Juffermans
- Department of Intensive Care, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - David S Y Ong
- Department of Intensive Care Medicine, University Medical Center Utrecht, Utrecht University, Room F06.149, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands.,Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Marc J M Bonten
- Department of Epidemiology, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands.,Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Olaf L Cremer
- Department of Intensive Care Medicine, University Medical Center Utrecht, Utrecht University, Room F06.149, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands
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Taheri N, Ardebili A, Amouzandeh-Nobaveh A, Ghaznavi-Rad E. Frequency of Antiseptic Resistance Among Staphylococcus aureus and Coagulase-Negative Staphylococci Isolated From a University Hospital in Central Iran. Oman Med J 2016; 31:426-432. [PMID: 27974958 DOI: 10.5001/omj.2016.86] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVES Reduced biocide susceptibility in Staphylococci is associated with various antiseptic resistance genes encoding efflux systems. Our aim was to determine the susceptibility to three disinfectant agents, including benzalkonium chloride (BAC), benzethonium chloride (BZT), and chlorhexidine digluconate (CHDG) among clinical isolates of Staphylococcus aureus and coagulase-negative Staphylococci (CoNS). METHODS The minimum inhibitory concentration (MIC) of 60 methicillin-resistant S. aureus (MRSA), 54 methicillin-sensitive S. aureus (MSSA) and 51 CoNS isolates from a single hospital to three biocidal agents (BAC, BZT, and CHDG) was determined. Biocide resistance genes (qacA/B, smr, qacG, qacH, qacJ, and norA) were analyzed by the polymerase chain reaction assay. RESULTS All isolates had MICs for BAC and BZT from 0.25 to 8 µg/mL, and for CHDG from 0.5 to 64 µg/mL. qacA/B was the most common biocide resistance gene among all 165 Staphylococcus isolates (76; 46%), which comprised 38 (63.3%) MRSA, 14 (25.9%) MSSA, and 24 (47%) CoNS. Eleven (6.7%) and 24 (14.5%) isolates among the 165 Staphylococci carried smr and norA genes, respectively. In contrast, other resistance genes such as qacG, qacH, and qacJ were absent in all Staphylococci studied. The qacA/B and smr genes were detected concomitantly in 3% of isolates, and 23.6% strains of the total 165 Staphylococcus isolates were negative for each studied gene. CONCLUSIONS The carriage of several biocide resistance genes, including qacA/B, smr, and norA, alone or concurrently, is associated with reduced susceptibility. Use of antiseptics may select for antibiotic-resistant strains and assist their survival in the healthcare environment.
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Affiliation(s)
- Nona Taheri
- Department of Medical Microbiology, Faculty of Medicine, Arak University of Medical Sciences, Arak, Iran
| | - Abdollah Ardebili
- Laboratory Sciences Research Center, Golestan University of Medical Sciences, Gorgan, Iran; Department of Microbiology, Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Iran
| | - Alireza Amouzandeh-Nobaveh
- Department of Medical Microbiology, Faculty of Medicine, Arak University of Medical Sciences, Arak, Iran
| | - Ehsanollah Ghaznavi-Rad
- Department of Medical Microbiology, Faculty of Medicine, Arak University of Medical Sciences, Arak, Iran; Molecular Research Center, Faculty of Medicine, Arak University of Medical Sciences, Arak, Iran
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5
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Akhi MT, Ghotaslou R, Memar MY, Asgharzadeh M, Varshochi M, Pirzadeh T, Alizadeh N. Frequency of MRSA in diabetic foot infections. Int J Diabetes Dev Ctries 2016. [DOI: 10.1007/s13410-016-0492-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Abstract
Cystic fibrosis is characterised by chronic polymicrobial infection and inflammation in the airways of patients. Antibiotic treatment regimens, targeting recognised pathogens, have substantially contributed to increased life expectancy of patients with this disease. Although the emergence of antimicrobial resistance and selection of highly antibiotic-resistant bacterial strains is of major concern, the clinical relevance in cystic fibrosis is yet to be defined. Resistance has been identified in recognised cystic fibrosis pathogens and in other bacteria (eg, Prevotella and Streptococcus spp) detected in the airway microbiota, but their role in the pathophysiology of infection and inflammation in chronic lung disease is unclear. Increased antibiotic resistance in cystic fibrosis might be attributed to a range of complex factors including horizontal gene transfer, hypoxia, and biofilm formation. Strategies to manage antimicrobial resistance consist of new antibiotics or localised delivery of antimicrobial agents, iron sequestration, inhibition of quorum-sensing, and resistome analysis. Determination of the contributions of every bacterial species to lung health or disease in cystic fibrosis might also have an important role in the management of antibiotic resistance.
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Affiliation(s)
- Laura J Sherrard
- CF and Airways Microbiology Group, Queen's University Belfast, Belfast, UK; School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Michael M Tunney
- CF and Airways Microbiology Group, Queen's University Belfast, Belfast, UK; School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - J Stuart Elborn
- CF and Airways Microbiology Group, Queen's University Belfast, Belfast, UK; Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK.
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7
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Sherrard LJ, Schaible B, Graham KA, McGrath SJ, McIlreavey L, Hatch J, Wolfgang MC, Muhlebach MS, Gilpin DF, Schneiders T, Elborn JS, Tunney MM. Mechanisms of reduced susceptibility and genotypic prediction of antibiotic resistance in Prevotella isolated from cystic fibrosis (CF) and non-CF patients. J Antimicrob Chemother 2014; 69:2690-8. [PMID: 24917582 DOI: 10.1093/jac/dku192] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVES To investigate mechanisms of reduced susceptibility to commonly used antibiotics in Prevotella cultured from patients with cystic fibrosis (CF), patients with invasive infection and healthy control subjects and to determine whether genotype can be used to predict phenotypic resistance. METHODS The susceptibility of 157 Prevotella isolates to seven antibiotics was compared, with detection of resistance genes (cfxA-type gene, ermF and tetQ), mutations within the CfxA-type β-lactamase and expression of efflux pumps. RESULTS Prevotella isolates positive for a cfxA-type gene had higher MICs of amoxicillin and ceftazidime compared with isolates negative for this gene (P < 0.001). A mutation within the CfxA-type β-lactamase (Y239D) was associated with ceftazidime resistance (P = 0.011). The UK CF isolates were 5.3-fold, 2.7-fold and 5.7-fold more likely to harbour ermF compared with the US CF, UK invasive and UK healthy control isolates, respectively. Higher concentrations of azithromycin (P < 0.001) and clindamycin (P < 0.001) were also required to inhibit the growth of the ermF-positive isolates compared with ermF-negative isolates. Furthermore, tetQ-positive Prevotella isolates had higher MICs of tetracycline (P = 0.001) and doxycycline (P < 0.001) compared with tetQ-negative isolates. Prevotella spp. were also shown, for the first time, to express resistance nodulation division (RND)-type efflux pumps. CONCLUSIONS This study has demonstrated that Prevotella isolated from various sources harbour a common pool of resistance genes and possess RND-type efflux pumps, which may contribute to tetracycline resistance. The findings indicate that antibiotic resistance is common in Prevotella spp., but the genotypic traits investigated do not reflect phenotypic antibiotic resistance in every instance.
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Affiliation(s)
- Laura J Sherrard
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Bettina Schaible
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Kathryn A Graham
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Stef J McGrath
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Leanne McIlreavey
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Joseph Hatch
- Cystic Fibrosis/Pulmonary Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Matthew C Wolfgang
- Cystic Fibrosis/Pulmonary Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Marianne S Muhlebach
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Deirdre F Gilpin
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Thamarai Schneiders
- Centre for Infection & Immunity, School of Medicine, Dentistry & Biomedical Science, Queen's University Belfast, Belfast, UK
| | - J Stuart Elborn
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK Centre for Infection & Immunity, School of Medicine, Dentistry & Biomedical Science, Queen's University Belfast, Belfast, UK
| | - Michael M Tunney
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
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8
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A rapid and high-throughput screening approach for methicillin-resistant Staphylococcus aureus based on the combination of two different real-time PCR assays. J Clin Microbiol 2014; 52:2861-7. [PMID: 24871220 DOI: 10.1128/jcm.00808-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen that has been responsible for major nosocomial epidemics worldwide. For infection control programs, rapid and adequate detection of MRSA is of great importance. We developed a rapid and high-throughput molecular screening approach that consists of an overnight selective broth enrichment, followed by mecA, mecC, and S. aureus-specific (SA442 gene) real-time PCR assays, with subsequent confirmation using a staphylococcal cassette chromosome mec element (SCCmec)-orfX-based real-time PCR assay (GeneOhm MRSA assay) and culture. Here, the results of the screening approach over a 2-year period are presented. During this period, a total of 13,387 samples were analyzed for the presence of MRSA, 2.6% of which were reported as MRSA positive. No MRSA isolates carrying the mecC gene were detected during this study. Based on the results of the real-time PCR assays only, 95.2% of the samples could be reported as negative within 24 h. Furthermore, the performance of these real-time PCR assays was evaluated using a set of 104 assorted MRSA isolates, which demonstrated high sensitivity for both the combination of mecA and mecC with SA442 and the BD GeneOhm MRSA assay (98.1% and 97.1%, respectively). This molecular screening approach proved to be an accurate method for obtaining reliable negative results within 24 h after arrival at the laboratory and contributes to improvement of infection control programs, especially in areas with a low MRSA prevalence.
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10
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Ginn AN, Zong Z, Wiklendt AM, Thomas LC, Merlino J, Gottlieb T, van Hal S, Harkness J, Macleod C, Bell SM, Leroi MJ, Partridge SR, Iredell JR. Limited diversity in the gene pool allows prediction of third-generation cephalosporin and aminoglycoside resistance in Escherichia coli and Klebsiella pneumoniae. Int J Antimicrob Agents 2013; 42:19-26. [PMID: 23706544 DOI: 10.1016/j.ijantimicag.2013.03.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 02/06/2013] [Accepted: 03/12/2013] [Indexed: 11/17/2022]
Abstract
Early appropriate antibiotic treatment reduces mortality in severe sepsis, but current methods to identify antibiotic resistance still generally rely on bacterial culture. Modern diagnostics promise rapid gene detection, but the apparent diversity of relevant resistance genes in Enterobacteriaceae is a problem. Local surveys and analysis of publicly available data sets suggested that the resistance gene pool is dominated by a relatively small subset of genes, with a very high positive predictive value for phenotype. In this study, 152 Escherichia coli and 115 Klebsiella pneumoniae consecutive isolates with a cefotaxime, ceftriaxone and/or ceftazidime minimum inhibitory concentration (MIC) of ≥ 2 μg/mL were collected from seven major hospitals in Sydney (Australia) in 2008-2009. Nearly all of those with a MIC in excess of European Committee on Antimicrobial Susceptibility Testing (EUCAST) resistance breakpoints contained one or more representatives of only seven gene types capable of explaining this phenotype, and this included 96% of those with a MIC ≥ 2 μg/mL to any one of these drugs. Similarly, 97% of associated gentamicin-non-susceptibility (MIC ≥ 8 μg/mL) could be explained by three gene types. In a country like Australia, with a background prevalence of resistance to third-generation cephalosporins of 5-10%, this equates to a negative predictive value of >99.5% for non-susceptibility and is therefore suitable for diagnostic application. This is an important proof-of-principle that should be tested in other geographic locations.
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Affiliation(s)
- Andrew N Ginn
- Centre for Infectious Diseases and Microbiology, University of Sydney, Westmead Hospital, Sydney, New South Wales, Australia
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Tunsjø HS, Follin-Arbelet B, Clausen NM, Ness Y, Leegaard TM, Bemanian V. A rapid, high-throughput screening method for carriage of methicillin-resistantStaphylococcus aureus. APMIS 2013; 121:865-70. [DOI: 10.1111/apm.12049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 12/03/2012] [Indexed: 11/28/2022]
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12
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Liu J, Cheng J, Zhang Y. Upconversion nanoparticle based LRET system for sensitive detection of MRSA DNA sequence. Biosens Bioelectron 2012; 43:252-6. [PMID: 23318548 DOI: 10.1016/j.bios.2012.12.026] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 12/07/2012] [Accepted: 12/10/2012] [Indexed: 10/27/2022]
Abstract
In this short communication we report an efficient and versatile method for the detection of methicillin-resistant staphylococcus aureus (MRSA) DNA sequence with high sensitivity and specificity. This method is based on upconversion nanoparticles (UCNs) and luminescence resonance energy transfer (LRET) between NaYF4:Yb, Er UCNs, the energy donor, and carboxytetramethylrhodamine (TAMRA), the energy acceptor. The NaYF4:Yb, Er UCNs were prepared with citrate capping thus dispersible in aqueous solutions. MRSA capture oligonucleotides were covalently immobilized onto the surface of the UCNs. TAMRA labeled MRSA DNA report oligonucleotides were brought close to the UCNs upon sandwich hybridization between the capture and report oligonucleotides and a long MRSA target DNA, resulting in an efficient LRET. Specific detection of MRSA DNA sequences with a detection limit as low as 0.18nM was achieved using this method. To the best of our knowledge, this is the first report to detect MRSA DNA sequence by using UCNs as energy donor through an efficient LRET process.
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Affiliation(s)
- Jinliang Liu
- Department of Bioengineering, Faculty of Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576
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13
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Didelot X, Bowden R, Wilson DJ, Peto TEA, Crook DW. Transforming clinical microbiology with bacterial genome sequencing. Nat Rev Genet 2012; 13:601-612. [PMID: 22868263 DOI: 10.1038/nrg3226] [Citation(s) in RCA: 516] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Whole-genome sequencing of bacteria has recently emerged as a cost-effective and convenient approach for addressing many microbiological questions. Here, we review the current status of clinical microbiology and how it has already begun to be transformed by using next-generation sequencing. We focus on three essential tasks: identifying the species of an isolate, testing its properties, such as resistance to antibiotics and virulence, and monitoring the emergence and spread of bacterial pathogens. We predict that the application of next-generation sequencing will soon be sufficiently fast, accurate and cheap to be used in routine clinical microbiology practice, where it could replace many complex current techniques with a single, more efficient workflow.
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Affiliation(s)
- Xavier Didelot
- Department of Statistics, University of Oxford, 1 South Parks Road, Oxford OX1 3TG, UK
| | - Rory Bowden
- Department of Statistics, University of Oxford, 1 South Parks Road, Oxford OX1 3TG, UK.,Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.,NIHR Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Daniel J Wilson
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.,Nuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Tim E A Peto
- Nuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, UK.,NIHR Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Derrick W Crook
- Nuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, UK.,NIHR Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
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