1
|
Zasowski EJ, Ali M, Anugo A, Ibragimova N, Dotson KM, Endres BT, Begum K, Alam MJ, Garey KW. Comparison of Risk Stratification Approaches to Identify Patients with Clostridioides difficile Infection at Risk for Multidrug-Resistant Organism Gut Microbiota Colonization. Infect Dis Ther 2023; 12:2005-2015. [PMID: 37436677 PMCID: PMC10505131 DOI: 10.1007/s40121-023-00843-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 06/26/2023] [Indexed: 07/13/2023] Open
Abstract
INTRODUCTION Multidrug-resistant organisms (MDRO) commonly colonize the gut microbiota of patients with Clostridioides difficile infection (CDI). This increases the likelihood of systemic infections with these MDROs. To help guide MDRO screening and/or empiric antibiotic therapy, we derived and compared predictive indices for MDRO gut colonization in patients with CDI. METHODS This was a multicenter, retrospective cohort study of adult patients with CDI from July 2017 to April 2018. Stool samples were screened for MDRO via growth and speciation on selective antibiotic media and confirmed using resistance gene polymerase chain reaction. A regression-based risk score for MDRO colonization was constructed. Predictive performance via area under the receiver operating characteristic curve (aROC) of this index was compared with two other simplified risk stratification approaches: (1) prior healthcare exposure and/or high-CDI risk antibiotics; (2) number of prior high-CDI risk antibiotics. RESULTS 50 (20.8%) of 240 included patients had MDRO colonization; 35 (14.6%) VRE, 18 (7.5%) MRSA, 2 (0.8%) CRE. Prior fluoroquinolone (aOR 2.404, 95% CI 1.095-5.279) and prior vancomycin (1.996, 95% CI 1.014-3.932) were independently associated with MDRO colonization while prior clindamycin (aOR 3.257, 95% CI 0.842-12.597) and healthcare exposure (aOR 2.138, 95% CI 0.964-4.740) were retained as explanatory variables. The regression-based risk score significantly predicted MDRO colonization (aROC 0.679, 95% CI 0.595-0.763), but was not significantly more predictive than prior healthcare exposure + prior antibiotics (aROC 0.646, 95% CI 0.565-0.727) or number of prior antibiotic exposures (aROC 0.642, 95% CI 0.554-0.730); P > 0.05 for both comparisons. CONCLUSION A simplified approach using prior healthcare exposure and receipt of prior antibiotics known to increase CDI risk identified patients at risk for MDRO gut microbiome colonization as effectively as individual patient/antibiotic risk modeling.
Collapse
Affiliation(s)
- Evan J Zasowski
- Department of Clinical Sciences, Touro University California College of Pharmacy, Vallejo, CA, USA.
- Department of Clinical Pharmacy, UCSF School of Pharmacy, San Francisco, CA, USA.
| | - Maryam Ali
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, TX, USA
| | - Ada Anugo
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, TX, USA
| | - Nayle Ibragimova
- Department of Clinical Sciences, Touro University California College of Pharmacy, Vallejo, CA, USA
| | - Kierra M Dotson
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, TX, USA
| | - Bradley T Endres
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, TX, USA
| | - Khurshida Begum
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, TX, USA
| | - M Jahangir Alam
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, TX, USA
| | - Kevin W Garey
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, TX, USA
| |
Collapse
|
2
|
Dutta T, Chowdhury SK, Ghosh NN, Chattopadhyay AP, Das M, Mandal V. Green synthesis of antimicrobial silver nanoparticles using fruit extract of Glycosmis pentaphylla and its theoretical explanations. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2021.131361] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
3
|
Interaction of green silver nanoparticles with model membranes: possible role in the antibacterial activity. Colloids Surf B Biointerfaces 2018; 171:320-326. [DOI: 10.1016/j.colsurfb.2018.07.044] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 06/29/2018] [Accepted: 07/20/2018] [Indexed: 11/18/2022]
|
4
|
Kotar T, Pirš M, Steyer A, Cerar T, Šoba B, Skvarc M, Poljšak Prijatelj M, Lejko Zupanc T. Evaluation of rectal swab use for the determination of enteric pathogens: a prospective study of diarrhoea in adults. Clin Microbiol Infect 2018; 25:733-738. [PMID: 30315956 DOI: 10.1016/j.cmi.2018.09.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 09/27/2018] [Accepted: 09/30/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVES A stool sample is the sample of choice for microbiological testing of enteric pathogens causing diarrhoea, but a rectal swab can be a more practical alternative. A prospective observational study was performed to evaluate the diagnostic performance of flocked rectal swab specimens using the syndromic molecular approach to determine the aetiology of diarrhoea in adults. METHODS We compared the performance of rectal swabs with stool samples as the reference standard in determining viral, bacterial and protozoal pathogens using real-time multiplex PCR as well as standard stool culture. Paired samples of stool and rectal swab specimens were collected from 304 adult patients with diarrhoea, presented at the Department of Infectious Diseases, University Medical Centre Ljubljana, between June 2016 and August 2017. RESULTS Overall sensitivity of rectal swab samples in the syndromic molecular approach was 83.2% (95% CI 77.2%-88.1%). Pathogen group-specific analysis of rectal swabs showed sensitivity of 65.6% (95% CI 52.7%-77.1%) for viruses and 57.1% (95% CI 28.9%-82.3%) for parasites. For bacteria, sensitivity was 86.5% (95% CI 79.5%-91.8%) when PCR was performed and 61.4% (95% CI 52.4%-69.9%) when culture for bacteria was performed. Mean threshold cycle (Ct) values for most pathogens were higher in rectal swab specimens than in stool specimens. CONCLUSIONS Our results indicate that rectal swabs can be used in the diagnosis of diarrhoea in adults when stool specimens are not available or when rapid aetiological determination is needed. However, rectal swabs should be analysed using a molecular approach. The mean Ct value for most pathogens is higher in rectal swab specimens than in stool specimens.
Collapse
Affiliation(s)
- T Kotar
- Infectious Diseases, University Clinical Centre Ljubljana, Ljubljana, Slovenia.
| | - M Pirš
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - A Steyer
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - T Cerar
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - B Šoba
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - M Skvarc
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - M Poljšak Prijatelj
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - T Lejko Zupanc
- Infectious Diseases, University Clinical Centre Ljubljana, Ljubljana, Slovenia
| |
Collapse
|
5
|
Abstract
Bacteremia and sepsis are conditions associated with high mortality and are of great impact to health care operations. Among the top causes of mortality in the United States, these conditions cause over 600 fatalities each day. Empiric, broad-spectrum treatment is a common but often a costly approach that may fail to effectively target the correct microbe, may inadvertently harm patients via antimicrobial toxicity or downstream antimicrobial resistance. To meet the diagnostic challenges of bacteremia and sepsis, laboratories must understand the complexity of diagnosing and treating septic patients, in order to focus on creating algorithms that can help direct a more targeted approach to antimicrobial therapy and synergize with existing clinical practices defined in new Surviving Sepsis Guidelines. Significant advances have been made in improving blood culture media; as yet no molecular or antigen-based method has proven superior for the detection of bacteremia in terms of limit of detection. Several methods for rapid molecular identification of pathogens from blood cultures bottles are available and many more are on the diagnostic horizon. Ultimately, early intervention by molecular detection of bacteria and fungi directly from whole blood could provide the most patient benefit and contribute to tailored antibiotic coverage of the patient early on in the course of the disease. Although blood cultures remain as the best means of diagnosing bacteremia and candidemia, complementary testing with antigen tests, microbiologic investigations from other body sites, and histopathology can often aid in the diagnosis of disseminated disease, and application of emerging nucleic acid test methods and other new technology may greatly impact our ability to bacteremic and septic patients, particularly those who are immunocompromised.
Collapse
|
6
|
Huang TS, Lee SSJ, Lee CC, Chen CY, Chen FC, Chen BC, Sy CL, Wu KS. Evaluation of a matrix-assisted laser desorption ionization-time of flight mass spectrometry assisted, selective broth method to screen for vancomycin-resistant enterococci in patients at high risk. PLoS One 2017; 12:e0179455. [PMID: 28609453 PMCID: PMC5469485 DOI: 10.1371/journal.pone.0179455] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Accepted: 05/29/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Bile esculin azide with vancomycin (BEAV) medium is a sensitive, but slightly less specific method for vancomycin-resistant enterococci (VRE) screening. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid method for identification of clinical pathogens. This study aimed to assess the performance of a novel combination screening test for VRE, using BEAV broth combined with MALDI-TOF MS. MATERIALS AND METHODS Clinical specimens were collected from patients at risk of VRE carriage, and tested by the novel combination method, using selective BEAV broth culture method followed by MALDI-TOF MS identification (SBEAVM). The reference method used for comparison was the ChromID VRE agar method. RESULTS A total of 135 specimens were collected from 78 patients, and 63 specimens tested positive for VRE positive using the ChromID VRE method (positive rate 46.7%). The sensitivity, specificity, positive predictive value, and negative predictive value of SBEAVM method after an incubation period of 28 hours were 93.7%, 90.3%, 89.4%, and 94.2%, respectively. The SBEAVM method when compared to the ChromID VRE method had a shorter turnaround time (29 vs. 48-72 hours) and lower laboratory cost ($2.11 vs. $3.23 per test). CONCLUSIONS This study demonstrates that SBEAVM is a rapid, inexpensive, and accurate method for use in VRE screening.
Collapse
Affiliation(s)
- Tsi-Shu Huang
- Division of Microbiology, Department of pathology and laboratory medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Susan Shin-Jung Lee
- Division of Microbiology, Department of pathology and laboratory medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- Division of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Chia-Chien Lee
- Division of Microbiology, Department of pathology and laboratory medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Chiu-Yen Chen
- Department of Nursing, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Fang-Chen Chen
- Department of Nursing, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- Infection Control Unit, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Bao-Chen Chen
- Division of Microbiology, Department of pathology and laboratory medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Cheng Len Sy
- Division of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Kuan-Sheng Wu
- Division of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
- * E-mail:
| |
Collapse
|
7
|
Silver Nanoparticles: Biosynthesis Using an ATCC Reference Strain of Pseudomonas aeruginosa and Activity as Broad Spectrum Clinical Antibacterial Agents. Int J Biomater 2016; 2016:5971047. [PMID: 27340405 PMCID: PMC4906205 DOI: 10.1155/2016/5971047] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 04/22/2016] [Accepted: 05/15/2016] [Indexed: 12/17/2022] Open
Abstract
Currently, the biosynthesis of silver-based nanomaterials attracts enormous attention owing to the documented antimicrobial properties of these ones. This study reports the extracellular biosynthesis of silver nanoparticles (Ag-NPs) using a Pseudomonas aeruginosa strain from a reference culture collection. A greenish culture supernatant of P. aeruginosa incubated at 37°C with a silver nitrate solution for 24 h changed to a yellowish brown color, indicating the formation of Ag-NPs, which was confirmed by UV-vis spectroscopy, transmission electron microscopy, and X-ray diffraction. TEM analysis showed spherical and pseudospherical nanoparticles with a distributed size mainly between 25 and 45 nm, and the XRD pattern revealed the crystalline nature of Ag-NPs. Also it provides an evaluation of the antimicrobial activity of the biosynthesized Ag-NPs against human pathogenic and opportunistic microorganisms, namely, Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Proteus mirabilis, Acinetobacter baumannii, Escherichia coli, P. aeruginosa, and Klebsiella pneumonia. Ag-NPs were found to be bioactive at picomolar concentration levels showing bactericidal effects against both Gram-positive and Gram-negative bacterial strains. This work demonstrates the first helpful use of biosynthesized Ag-NPs as broad spectrum bactericidal agents for clinical strains of pathogenic multidrug-resistant bacteria such as methicillin-resistant S. aureus, A. baumannii, and E. coli. In addition, these Ag-NPs showed negligible cytotoxic effect in human neutrophils suggesting low toxicity to the host.
Collapse
|
8
|
Overview of Molecular Diagnostics in Multiple-Drug-Resistant Organism Prevention: Focus on Multiple-Drug-Resistant Gram-Negative Bacterial Organisms. Mol Microbiol 2016. [DOI: 10.1128/9781555819071.ch17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
9
|
Radiolabeling, biological evaluation and molecular docking of delafloxacin: a novel methicillin-resistant Staphylococcus aureus infection radiotracer. J Radioanal Nucl Chem 2015. [DOI: 10.1007/s10967-015-4586-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
10
|
Attieh R, Gagnon MP, Krein SL. How can implementing an infection prevention and control (IPC) technology transform healthcare practices and outcomes for patients? ACTA ACUST UNITED AC 2014. [DOI: 10.1071/hi14003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
11
|
Jenison RD, Bucala R, Maul D, Ward DC. Thin-film technology for direct visual detection of nucleic acid sequences: applications in clinical research. Expert Rev Mol Diagn 2014; 6:89-99. [PMID: 16359270 DOI: 10.1586/14737159.6.1.89] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Certain optical conditions permit the unaided eye to detect thickness changes on surfaces on the order of 20 A, which are of similar dimensions to monomolecular interactions between proteins or hybridization of complementary nucleic acid sequences. Such detection exploits specific interference of reflected white light, wherein thickness changes are perceived as surface color changes. This technology, termed thin-film detection, allows for the visualization of subattomole amounts of nucleic acid targets, even in complex clinical samples. Thin-film technology has been applied to a broad range of clinically relevant indications, including the detection of pathogenic bacterial and viral nucleic acid sequences and the discrimination of sequence variations in human genes causally related to susceptibility or severity of disease.
Collapse
Affiliation(s)
- Robert D Jenison
- Inverness Medical-Biostar Inc., 331 South 104 St., Louisville, CO 80027, USA.
| | | | | | | |
Collapse
|
12
|
Gozaydin A, Kose S, Ece G, Ersan G, Gonullu M. Detection of Vancomycin Resistant Enterococci from Rectal Swab Samples by Becton-Dickinson GeneOhm VanR assay and Culture at ICU of a Tertiary Care Center in Turkey. Pak J Med Sci 2013; 29:682-6. [PMID: 24353607 PMCID: PMC3809269 DOI: 10.12669/pjms.292.2567] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 12/27/2012] [Accepted: 12/29/2012] [Indexed: 11/23/2022] Open
Abstract
Objectives: Vancomycin resistance is due to change in ligase enzyme that destroys the binding of the drug. The gold standard is culture; but now molecular methods have also been developed. The aim was to detect the VRE rate at ICUs by culture and BD GeneOhm™ VanR and compare the results of both assays. Methodology: 135 perianal swabs were taken from the patients at ICUs between January 1st 2009 and April 30th 2009. Samples were identified by conventional methods and BD GeneOhm VanR assay. Results: In newborn ICU, 41 patients (74.6%) were negative by both methods. Two (3.6%) were positive by both methods. Twelve (21.8%) of them were culture negative and PCR positive. In adult ICU, 73 (91.3%) patients were negative by both methods. Seven patients (8.8%) were positive by molecular method only. Conclusion: This study showed low VRE positivity due to factors like inhibition in PCR or culture negativity due low inoculum for bacterial growth. Early detection of VRE is an important issue especially in ICUs and molecular techniques are important tools; but against all, we still need to confirm this method with culture based techniques and in order to do this further studies with higher number of patients with VRE colonisation are required.
Collapse
Affiliation(s)
- Ayhan Gozaydin
- Ayhan Gozaydin, Infectious Diseases and Clinical Microbiology Specialist, Department of Infectious Diseases and Clinical Microbiology, Tepecik Education and Research Hospital, Izmir, Turkey
| | - Sukran Kose
- Sukran Kose, Infectious Diseases and Clinical Microbiology Specialist, Department of Infectious Diseases and Clinical Microbiology, Tepecik Education and Research Hospital, Izmir, Turkey
| | - Gulfem Ece
- Gulfem Ece, Clinical Microbiology Specialist, Department of Infectious Diseases and Clinical Microbiology, Tepecik Education and Research Hospital, Izmir, Turkey
| | - Gursel Ersan
- Gursel Ersan, Infectious Diseases and Clinical Microbiology Specialist, Department of Infectious Diseases and Clinical Microbiology, Tepecik Education and Research Hospital, Izmir, Turkey
| | - Mustafa Gonullu
- Mustafa Gonullu, Anesthesiology and Reanimation Specialist, Department of Anesthesiology and Reanimation, Tepecik Education and Research Hospital, Izmir, Turkey
| |
Collapse
|
13
|
Coban AY, Darka O, Tasdelen Fisgin N, Cihan CC, Bilgin K, Akgunes A, Guven T, Dokuzoguz B, Birinci A, Durupinar B. The Resazurin Microplate Method for Rapid Detection of Vancomycin Resistance in Enterococci. J Chemother 2013; 17:361-6. [PMID: 16167513 DOI: 10.1179/joc.2005.17.4.361] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Vancomycin-resistant enterococci (VRE) are a serious challenge for physicians because of the limited treatment options for infections caused by this organism. Prevention of VRE transmission in hospitals requires early detection of infected or colonized patients. Therefore rapid and correct detection of vancomycin resistance is essential. In this study, we use the resazurin microplate method (RMM), which is a modification of the NCCLS and BSAC broth microdilution methods to rapidly determine the susceptibilities of clinical enterococci isolates to vancomycin. The alteration in the RMM was relevant to the final bacterial count. In this method, inoculum that was 10-fold higher than standard methods was used. A total of 80 enterococci, including 11 VRE isolates and 6 vancomycin intermediate isolates, were screened with this modified colorimetric broth microdilution method. After 4 h of incubation 30 microl of 0.01% resazurin solution were added to each well and the plates were reincubated for color change for 5-10 min. The MICs were obtained at the 4th h. The results were in exact agreement with the NCCLS and the BSAC microdilution methods. Absolute and essential agreements were 100% and there were no minor, major or very major errors. In conclusion, this modified colorimetric broth microdilution method can be used as a reliable, easy, cheap and rapid method for early detection of VRE. Moreover, this method has the potential of being used to test the susceptibilities of different bacteria to other antibiotics.
Collapse
Affiliation(s)
- A Y Coban
- Ondokuz Mayis University, Medical School, Department of Microbiology and Clinical Microbiology, Samsun, Turkey.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Diekema DJ, Pfaller MA. Rapid Detection of Antibiotic-Resistant Organism Carriage for Infection Prevention. Clin Infect Dis 2013; 56:1614-20. [DOI: 10.1093/cid/cit038] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
15
|
Chen YW, Wang H, Hupert M, Soper SA. Identification of methicillin-resistant Staphylococcus aureus using an integrated and modular microfluidic system. Analyst 2013; 138:1075-83. [DOI: 10.1039/c2an36430a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
16
|
Guntupalli R, Sorokulova I, Olsen E, Globa L, Pustovyy O, Moore T, Chin B, Barbaree J, Vodyanoy V. Detection and identification of methicillin resistant and sensitive strains of Staphylococcus aureus using tandem measurements. J Microbiol Methods 2012; 90:182-91. [DOI: 10.1016/j.mimet.2012.05.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Revised: 04/28/2012] [Accepted: 05/04/2012] [Indexed: 02/01/2023]
|
17
|
Tangjitjaroenkun J, Chavasiri W, Thunyaharn S, Yompakdee C. Bactericidal effects and time–kill studies of the essential oil from the fruits ofZanthoxylum limonellaon multi-drug resistant bacteria. JOURNAL OF ESSENTIAL OIL RESEARCH 2012. [DOI: 10.1080/10412905.2012.692907] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
18
|
Kaiser TDL, Pacheco FC, Lima AAD, Pereira EM, Santos KRND, Nunes APF. [Evaluation of methods commonly used in laboratories to determine the susceptibility to oxacillin among Staphylococcus sp samples isolated from a hospital in Vitória, State of Espírito Santo]. Rev Soc Bras Med Trop 2010; 43:298-303. [PMID: 20563500 DOI: 10.1590/s0037-86822010000300017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 04/26/2010] [Indexed: 11/21/2022] Open
Abstract
INTRODUCTION The genus Staphylococcus is of great importance because of its high prevalence in hospital infections and because it presents high rates of resistance to oxacillin and other antimicrobials. Thus, evaluation of the accuracy of the phenotypic methods that are used to determine the profile of antimicrobial resistance is essential to ensure that the most appropriate therapy is chosen. METHODS One hundred and fourteen strains of Staphylococcus sp (53 S. aureus and 61 CNS) were used to evaluate the accuracy of the methods of disk diffusion, agar microdilution, oxacillin screening agar and automated systems, in comparison with PCR for investigating resistance to oxacillin. RESULTS The mecA gene was detected in 48 strains (42.1%), and 27 strains (23.7%) showed discrepant results in at least one of the methods (74.1% of CNS, 25.9% of S. aureus). For S. aureus, with the exception of the Microscan Walkaway, all the methods showed 100% specificity and sensitivity. In relation to CNS, the automated system and cefoxitin disk had lower accuracy. CONCLUSIONS Use of two methods should be the best option for improved accuracy, especially when the diagnostic laboratory only uses an automated system or oxacillin disk diffusion test. Combination of these methods with others presented almost 100% sensitivity and specificity in our study.
Collapse
Affiliation(s)
- Thais Dias Lemos Kaiser
- Laboratório de Resistência Bacteriana, Departamento Patologia, Universidade Federal do Espírito Santo, Vitória, ES, Brazil
| | | | | | | | | | | |
Collapse
|
19
|
A new multiplex PCR assay for the simultaneous detection of vancomycin-resistant enterococci from rectal swabs. J Infect 2010; 60:354-9. [DOI: 10.1016/j.jinf.2010.02.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Revised: 02/22/2010] [Accepted: 02/24/2010] [Indexed: 11/19/2022]
|
20
|
Drew RH, Townsend ML. Antifungal Drug Resistance: Clinical Relevance and Impact of Antifungal Drug Use. CURRENT FUNGAL INFECTION REPORTS 2010. [DOI: 10.1007/s12281-010-0013-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
21
|
Wolk DM, Fiorello AB. Code Sepsis: Rapid Methods To Diagnose Sepsis and Detect Hematopathogens. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.clinmicnews.2010.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
22
|
Multiplex PCR-ligation detection reaction assay for simultaneous detection of drug resistance and toxin genes from Staphylococcus aureus, Enterococcus faecalis, and Enterococcus faecium. J Clin Microbiol 2009; 48:277-80. [PMID: 19864481 DOI: 10.1128/jcm.01411-09] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A multiplex PCR-ligation detection reaction (PCR-LDR) assay was developed for rapid detection of methicillin, tetracycline, and vancomycin resistance, as well as toxic shock toxin and Panton-Valentine leukocidin. The assay was tested on 470 positive blood culture bottles containing Staphylococcus aureus or enterococci. PCR-LDR exhibited a sensitivity and specificity of > or = 98% for all components except tetracycline resistance, which had a sensitivity of 94.7%. Rapid and sensitive detection of antimicrobial resistance and virulence genes could help guide therapy and appropriate infection control measures.
Collapse
|
23
|
Affiliation(s)
- Stacy Coffman
- The University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| |
Collapse
|
24
|
Camara JE, Hays FA. Discrimination between wild-type and ampicillin-resistant Escherichia coli by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Anal Bioanal Chem 2007; 389:1633-8. [PMID: 17849103 DOI: 10.1007/s00216-007-1558-7] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2007] [Revised: 08/08/2007] [Accepted: 08/15/2007] [Indexed: 11/26/2022]
Abstract
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was optimized to discriminate between wild-type and ampicillin-resistant Escherichia coli. Only ampicillin-resistant E. coli displayed an m/z approximately 29,000 peak, which was confirmed as beta-lactamase by in-gel digestion followed by peptide mass fingerprinting. Rapid MALDI-TOF MS detection of antibiotic-resistance could fulfill an important clinical need, providing critical phenotypic information beyond genus-species identification.
Collapse
Affiliation(s)
- Johanna E Camara
- Analytical Chemistry Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA.
| | | |
Collapse
|
25
|
Diekema DJ, Edmond MB. Look before You Leap: Active Surveillance for Multidrug-Resistant Organisms. Clin Infect Dis 2007; 44:1101-7. [PMID: 17366459 DOI: 10.1086/512820] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2006] [Accepted: 01/10/2007] [Indexed: 01/21/2023] Open
Abstract
Hospitals in the United States are under increasing pressure to perform active surveillance cultures for detection of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) among newly admitted patients. Results of such cultures can then be used to direct contact precautions to prevent transmission of MRSA and VRE in the health care setting. However, using active surveillance cultures to expand contact precautions is a complicated and resource-intensive intervention that has the potential for several unintended adverse consequences. Therefore, careful forethought and preparation should precede the institution of any active surveillance culture program. We review the following important steps that should be performed when planning any such intervention: preparing the laboratory and reducing the turnaround time for screening tests, monitoring and optimizing the intervention of instituting contact precautions, monitoring and ameliorating the known adverse effects of contact precautions, and measuring important outcomes to evaluate the effectiveness of a program of active surveillance cultures and contact precautions.
Collapse
|
26
|
Francois P, Hernandez D, Schrenzel J. Genome content determination in methicillin-resistant Staphylococcus aureus. Future Microbiol 2007; 2:187-98. [PMID: 17661655 DOI: 10.2217/17460913.2.2.187] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Staphylococcus aureus is a major pathogen responsible for both nosocomial and community-acquired infections. While the first S. aureus isolates displaying resistance to methicillin were reported in the early 1960s, endemic strains of methicillin-resistant S. aureus (MRSA) carrying multiple resistance determinants only became a worldwide nosocomial problem in the early 1980s, carrying a threefold attributable cost and a threefold excess length of hospital stay when compared with methicillin-susceptible S. aureus bacteremia. Recent efforts in the field of high-throughput sequencing resulted in the release of several MRSA genome sequences enabling the development of massively parallel tools to study clinical isolates of MRSA at the organism scale. Microarrays covering whole genomes and high-throughput sequencing devices are the two main techniques currently utilizable for whole-genome characterization. These tools not only provide information for the development of genotyping assays but also allow evaluation of potential virulence of the strains, by enumerating genetic-encoded resistance markers and toxin content. This appears particularly attractive for understanding the epidemiology of MRSA and the relationship between genome content on one side and virulence potential or epidemicity on the other side. In addition, sequence information is mandatory for the development of molecular tests allowing the rapid identification, genotyping and characterization of clinical isolates.
Collapse
Affiliation(s)
- Patrice Francois
- Service of Infectious Diseases, Genomic Research Laboratory, Department of Internal Medicine, Geneva 14, Switzerland.
| | | | | |
Collapse
|
27
|
Harbarth S, Masuet-Aumatell C, Schrenzel J, Francois P, Akakpo C, Renzi G, Pugin J, Ricou B, Pittet D. Evaluation of rapid screening and pre-emptive contact isolation for detecting and controlling methicillin-resistant Staphylococcus aureus in critical care: an interventional cohort study. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2006; 10:R25. [PMID: 16469125 PMCID: PMC1550853 DOI: 10.1186/cc3982] [Citation(s) in RCA: 150] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2005] [Revised: 12/26/2005] [Accepted: 01/03/2006] [Indexed: 11/10/2022]
Abstract
INTRODUCTION Rapid diagnostic tests may allow early identification of previously unknown methicillin-resistant Staphylococcus aureus (MRSA) carriers at intensive care unit (ICU) admission. The aim of this study was twofold: first, to assess whether a new molecular MRSA screening test can substantially decrease the time between ICU admission and identification of MRSA carriers; and, second, to examine the combined effect of rapid testing and pre-emptive contact isolation on MRSA infections. METHOD Since November 2003, patients admitted for longer than 24 hours to two adult ICUs were screened systematically on admission using quick, multiplex immunocapture-coupled PCR (qMRSA). Median time intervals from admission to notification of test results were calculated for a five-month intervention phase (November 2003-March 2004) and compared with a historical control period (April 2003-October 2003) by nonparametric tests. ICU-acquired MRSA infection rates were determined for an extended surveillance period (January 2003 through August 2005) and analyzed by Poisson regression methods. RESULTS During the intervention phase, 97% (450/462) of patients admitted to the surgical ICU and 80% (470/591) of patients admitted to the medical ICU were screened. On-admission screening identified the prevalence of MRSA to be 6.7% (71/1053). Without admission screening, 55 previously unknown MRSA carriers would have been missed in both ICUs. Median time from ICU admission to notification of test results decreased from 87 to 21 hours in the surgical ICU (P < 0.001) and from 106 to 23 hours in the medical ICU (P < 0.001). In the surgical ICU, 1,227 pre-emptive isolation days for 245 MRSA-negative patients were saved by using the qMRSA test. After adjusting for colonization pressure, the systematic on-admission screening and pre-emptive isolation policy was associated with a reduction in medical ICU acquired MRSA infections (relative risk 0.3, 95% confidence interval 0.1-0.7) but had no effect in the surgical ICU (relative risk 1.0, 95% confidence interval 0.6-1.7). CONCLUSION The qMRSA test decreased median time to notification from four days to one day and helped to identify previously unknown MRSA carriers rapidly. A strategy linking the rapid screening test to pre-emptive isolation and cohorting of MRSA patients substantially reduced MRSA cross-infections in the medical but not in the surgical ICU.
Collapse
Affiliation(s)
- Stephan Harbarth
- Associate Hospital Epidemiologist, Infection Control Program, Geneva University Hospitals, Geneva, Switzerland
| | | | - Jacques Schrenzel
- Director, Clinical Microbiology Laboratory, Geneva University Hospitals, Geneva, Switzerland
| | - Patrice Francois
- Senior Research Associate, Genomic Research Laboratory, Geneva University Hospitals, Geneva, Switzerland
| | - Christophe Akakpo
- Infection Control Practitioner, Infection Control Program, Geneva University Hospitals, Geneva, Switzerland
| | - Gesuele Renzi
- Laboratory technician, Clinical Microbiology Laboratory, Geneva University Hospitals, Geneva, Switzerland
| | - Jerome Pugin
- Attending, Intensive Care Division, Geneva University Hospitals, Geneva, Switzerland
| | - Bara Ricou
- Attending, Intensive Care Division, Geneva University Hospitals, Geneva, Switzerland
| | - Didier Pittet
- Director, Infection Control Program, Geneva University Hospitals, Geneva, Switzerland
| |
Collapse
|
28
|
Struelens MJ, Denis O. Rapid molecular detection of methicillin-resistant Staphylococcus aureus: a cost-effective tool for infection control in critical care? Crit Care 2006; 10:128. [PMID: 16563177 PMCID: PMC1550907 DOI: 10.1186/cc4855] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Control strategies for methicillin-resistant Staphylococcus aureus (MRSA) in critical care remain debated. Timely detection of MRSA carriers is crucial to an effective isolation policy. In this issue, Harbarth and colleagues report rapid MRSA screening among intensive care unit-admitted patients using a PCR assay. Preemptive isolation for all admissions until screened negative for MRSA was associated with a reduction of intensive care unit-acquired MRSA infections in one of two study units. The data provide preliminary evidence to the effectiveness of a MRSA control strategy combining rapid screening by a molecular method and preventive isolation. Further controlled studies are needed to evaluate the cost-effectiveness of this intervention.
Collapse
Affiliation(s)
- Marc J Struelens
- Department of Microbiology, Université Libre de Bruxelles-Hopital Erasme, Brussels, Belgium.
| | | |
Collapse
|
29
|
Brady A, Loughlin R, Gilpin D, Kearney P, Tunney M. In vitro activity of tea-tree oil against clinical skin isolates of meticillin-resistant and -sensitive Staphylococcus aureus and coagulase-negative staphylococci growing planktonically and as biofilms. J Med Microbiol 2006; 55:1375-1380. [PMID: 17005786 DOI: 10.1099/jmm.0.46558-0] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The susceptibility of Staphylococcus aureus [meticillin-resistant (MRSA) and meticillin-sensitive (MSSA)] and coagulase-negative staphylococci (CoNS), which respectively form part of the transient and commensal skin flora, to tea-tree oil (TTO) was compared using broth microdilution and quantitative in vitro time–kill test methods. MRSA and MSSA isolates were significantly less susceptible than CoNS isolates, as measured by both MIC and minimum bactericidal concentration. A significant decrease in the mean viable count of all isolates in comparison with the control was seen at each time interval in time–kill assays. However, the only significant difference in the overall mean log10 reduction in viable count between the groups of isolates was between CoNS and MSSA at 3 h, with CoNS isolates demonstrating a significantly lower mean reduction. To provide a better simulation of in vivo conditions on the skin, where bacteria are reported to grow as microcolonies encased in glycocalyx, the bactericidal activity of TTO against isolates grown as biofilms was also compared. Biofilms formed by MSSA and MRSA isolates were completely eradicated following exposure to 5 % TTO for 1 h. In contrast, of the biofilms formed by the nine CoNS isolates tested, only five were completely killed, although a reduction in viable count was apparent for the other four isolates. These results suggest that TTO exerts a greater bactericidal activity against biofilm-grown MRSA and MSSA isolates than against some biofilm-grown CoNS isolates.
Collapse
Affiliation(s)
- Aaron Brady
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Ryan Loughlin
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Deirdre Gilpin
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Paddy Kearney
- Microbiology Department, United Hospitals Trust, Antrim, BT41, UK
| | - Michael Tunney
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| |
Collapse
|
30
|
Singh A, Goering RV, Simjee S, Foley SL, Zervos MJ. Application of molecular techniques to the study of hospital infection. Clin Microbiol Rev 2006; 19:512-30. [PMID: 16847083 PMCID: PMC1539107 DOI: 10.1128/cmr.00025-05] [Citation(s) in RCA: 176] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Nosocomial infections are an important source of morbidity and mortality in hospital settings, afflicting an estimated 2 million patients in United States each year. This number represents up to 5% of hospitalized patients and results in an estimated 88,000 deaths and 4.5 billion dollars in excess health care costs. Increasingly, hospital-acquired infections with multidrug-resistant pathogens represent a major problem in patients. Understanding pathogen relatedness is essential for determining the epidemiology of nosocomial infections and aiding in the design of rational pathogen control methods. The role of pathogen typing is to determine whether epidemiologically related isolates are also genetically related. To determine molecular relatedness of isolates for epidemiologic investigation, new technologies based on DNA, or molecular analysis, are methods of choice. These DNA-based molecular methodologies include pulsed-field gel electrophoresis (PFGE), PCR-based typing methods, and multilocus sequence analysis. Establishing clonality of pathogens can aid in the identification of the source (environmental or personnel) of organisms, distinguish infectious from noninfectious strains, and distinguish relapse from reinfection. The integration of molecular typing with conventional hospital epidemiologic surveillance has been proven to be cost-effective due to the associated reduction in the number of nosocomial infections. Cost-effectiveness is maximized through the collaboration of the laboratory, through epidemiologic typing, and the infection control department during epidemiologic investigations.
Collapse
Affiliation(s)
- Aparajita Singh
- Department of Medicine, Section of Infectious Diseases, Henry Ford Hospital, Wayne State University School of Medicine, Detroit, MI 48202, USA
| | | | | | | | | |
Collapse
|
31
|
|
32
|
Abstract
In the 21st century, one of the greatest challenges to public health and clinical microbiologists is the rapid detection and identification of emerging and reemerging pathogens. Complex factors such as genetic variation in the host and pathogen, environmental changes, population pressures, and global travel can all influence the emergence of infectious diseases. The SARS epidemic of 2003 highlighted the potential of an emerging pathogen to spread globally in a very short time frame (Peruski and Peruski, 2003). The diagnostics of such infectious diseases has been greatly affected in the past 20 years. No longer is cultivation and microscopy the only means of detecting infectious agents. With the introduction of molecular diagnostics, the ability to detect minute amounts of microbial nucleic acids in clinical specimens has revolutionized clinical microbiology. In particular, the utility of PCR allows the detection and quantitation of specific agents in a matter of hours. PCR sequencing of specific segments of nucleic acid allows for the determination of specific drug resistance that now aids in guiding viral therapies.
Collapse
|
33
|
Metan G, Zarakolu P, Unal S. Rapid detection of antibacterial resistance in emerging Gram-positive cocci. J Hosp Infect 2005; 61:93-9. [PMID: 16009459 DOI: 10.1016/j.jhin.2005.02.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2005] [Accepted: 02/28/2005] [Indexed: 01/07/2023]
Abstract
Effective infection control efforts obviously depend on the performance of the laboratory to detect emerging resistant pathogens accurately and confirm resistance patterns by additional methods to conventional or automated systems. Conventional methods still remain the predominant approaches for detection and identification of bacteria and resistance patterns. However, the estimated time for conventional tests to detect resistance is at least 24-48 h for methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci and other epidemiologically important pathogens. Most of the tests used for rapid detection require bacterial growth in culture. There is an important clinical need for rapid detection of bacteria directly from patient samples. Rapid methods based on immunological or molecular technologies have contributed significantly. Molecular assays for several resistance markers are reliable, such as for mecA in staphylococci and vanA in enterococci. However, for other resistance markers, there is a lack of field testing. Cost-effectiveness of rapid detection of antibacterial resistance is another concern. Molecular assays would be useful for tertiary hospitals considering the investment costs and requirement of expert laboratory staff. For smaller centres, rapid tests based on immunological techniques may be a better choice.
Collapse
Affiliation(s)
- G Metan
- Section of Infectious Diseases, Department of Medicine, Hacettepe University School of Medicine, 06100 Ankara, Turkey
| | | | | |
Collapse
|
34
|
Kaplan S, Marlowe EM, Hogan JJ, Doymaz M, Bruckner DA, Simor AE. Sensitivity and specificity of a rapid rRNA gene probe assay for simultaneous identification of Staphylococcus aureus and detection of mecA. J Clin Microbiol 2005; 43:3438-42. [PMID: 16000472 PMCID: PMC1169175 DOI: 10.1128/jcm.43.7.3438-3442.2005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
rRNA gene sequences were used for identification and target adequacy controls in a DNA probe assay to identify isolates as Staphylococcus and, more specifically, as S. aureus within 1 hour. mecA status was simultaneously determined using a specific DNA probe. The target adequacy control guarded against false-negative mecA results.
Collapse
Affiliation(s)
- Shannon Kaplan
- Gen-Probe Incorporated, 10210 Genetic Center Drive, San Diego, CA 92121-4362, USA
| | | | | | | | | | | |
Collapse
|
35
|
Woodford N, Sundsfjord A. Molecular detection of antibiotic resistance: when and where? J Antimicrob Chemother 2005; 56:259-61. [PMID: 15967769 DOI: 10.1093/jac/dki195] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Antibiotic resistance is a key issue affecting public health, and diagnostic bacteriology laboratories are essential for prompt recognition of resistant isolates. Determination of susceptibility or resistance using phenotypic tests is a 'gold standard' against which newer technologies are compared in terms of performance, cost and ease of use. Molecular methods for detecting resistance are myriad, and are used widely in academia and in reference laboratories, but gaining a significant foothold in diagnostic laboratories is proving more difficult. However, if used widely in a diagnostic setting, these techniques would impact more directly on patient care and would be valuable infection control tools, e.g. by rapidly confirming patients colonized by resistant bacteria. The cost of molecular assays may be considered prohibitive, and this is compounded by the daunting variety of proprietary platforms available; most diagnostic laboratories would prefer to invest their capital and to train their staff in a single versatile technology. In a market that has no clear leader, many laboratories are understandably reluctant to gamble on making the correct choice. If molecular detection of resistance is to achieve wide acceptance, manufacturers must broaden the repertoires of their technologies, develop more off-the-shelf applications with in-built quality control, and make them suitable for laboratory personnel with no specialist expertise in molecular biology.
Collapse
Affiliation(s)
- Neil Woodford
- Antibiotic Resistance Monitoring and Reference Laboratory, Centre for Infections, Health Protection Agency, 61 Colindale Avenue, London NW9 5HT, UK.
| | | |
Collapse
|
36
|
Sundsfjord A, Simonsen GS, Haldorsen BC, Haaheim H, Hjelmevoll SO, Littauer P, Dahl KH. Genetic methods for detection of antimicrobial resistance. APMIS 2005; 112:815-37. [PMID: 15638839 DOI: 10.1111/j.1600-0463.2004.apm11211-1208.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Accurate and rapid diagnostic methods are needed to guide antimicrobial therapy and infection control interventions. Advances in real-time PCR have provided a user-friendly, rapid and reproducible testing platform catalysing an increased use of genetic assays as part of a wider strategy to minimize the development and spread of antimicrobial-resistant bacteria. In this review we outline the principal features of genetic assays in the detection of antimicrobial resistance, their advantages and limitations, and discuss specific applications in the detection of methicillin-resistant Staphylococcus aureus, glycopeptide-resistant enterococci, aminoglycoside resistance in staphylococci and enterococci, broad-spectrum resistance to beta-lactam antibiotics in gram-negative bacteria, as well as genetic elements involved in the assembly and spread of antimicrobial resistance.
Collapse
|
37
|
He H. Mannopeptimycins, a novel class of glycopeptide antibiotics active against gram-positive bacteria. Appl Microbiol Biotechnol 2005; 67:444-52. [PMID: 15702316 DOI: 10.1007/s00253-004-1884-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2004] [Revised: 12/14/2004] [Accepted: 12/15/2004] [Indexed: 11/30/2022]
Abstract
Mannopeptimycins alpha-epsilon, novel glycopeptides with activity against methicillin-resistant staphylococci and vancomycin-resistant enterococci, are purified from the fermentation broth of a strain of Streptomyces hygroscopicus, LL-AC98, and their structures characterized using spectroscopic analyses and chemical methods. The SAR data of the natural and synthetic esters demonstrate that the presence of hydrophobic groups near the terminal mannosyl moiety is critical for antibacterial potency. Scalable syntheses of 4,6-cyclic acetals and ketals on this moiety are used to produce significant quantities of the respective mannopeptimycin derivatives. These acetal and ketal derivatives exhibit potent activities against susceptible and resistant Gram-positive bacteria in both in vitro and in vivo experiments, comparable with or exceeding the activity of vancomycin. Studies on the mechanism of action suggest that the mannopeptimycins interfere with the late stages of bacterial cell wall biosynthesis. It is believed that these antibiotics inhibit the transglycosylation by binding to the transglycosylase substrate, lipid II.
Collapse
Affiliation(s)
- Haiyin He
- Natural Products Research, Chemical and Screening Sciences, Wyeth Research, Pearl River, NY 10965, USA.
| |
Collapse
|
38
|
Polgreen PM, Herwaldt LA. Staphylococcus aureus colonization and nosocomial infections: Implications for prevention. Curr Infect Dis Rep 2004; 6:435-441. [PMID: 15538980 DOI: 10.1007/s11908-004-0062-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Colonization with Staphylococcus aureus is a risk factor for invasive S. aureus infections. Intranasal mupirocin has effectively eradicated S. aureus colonization and appears to prevent S. aureus nosocomial infections in some patient populations. In hospitals and communities where mupirocin use has been widespread, resistance to the drug has emerged. New strategies and agents are needed if we want to significantly decrease the risk of S. aureus infections.
Collapse
Affiliation(s)
- Philip M Polgreen
- University of Iowa Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA 52242, USA.
| | | |
Collapse
|