The use of automated systems in identification and susceptibility tests can improve antimicrobial therapy, and positively impact clinical outcomes with a decrease in antimicrobial resistance, ...hospitalization time, costs, and mortality.
The aim of this study was to evaluate the clinical impact of an automated method for identification and susceptibility testing of microbial isolates.
This was a retrospective cross-sectional study aimed to analyse the results before and after the implementation period of a VITEK 2 system in a Brazilian university hospital. Based on data from medical records, patients with a positive culture of clinical samples from January to July 2017 (conventional method) and from August to December 2017 (automated method) were included in this study. Demographic data, hospitalization time, time interval between culture collection and results, culture results and site, susceptibility profile, minimum inhibitory concentration, and outcome data were evaluated. Chi-square and Fischer's tests were used in the analysis.
Of the total samples, 836 were considered valid by the inclusion criteria, with 219 patients before VITEK 2 system implementation group and 545 in the post-implementation group. The comparison between the two periods showed a reduction of 25 % of the time to culture reports, a decrease of 33.5 to 17.0 days of hospitalization, and a reduction in mortality from 44.3-31.0 %, respectively.
The VITEK 2 system provided early access to appropriate antimicrobial therapy for patients and effected a positive clinical impact with a reduction in mortality and hospitalization time.
Currently microorganisms are best identified using 16S rRNA and 18S rRNA gene sequencing. However, in recent years matrix assisted laser desorption ionization-time of flight mass spectrometry ...(MALDI-TOF MS) has emerged as a potential tool for microbial identification and diagnosis. During the MALDI-TOF MS process, microbes are identified using either intact cells or cell extracts. The process is rapid, sensitive, and economical in terms of both labor and costs involved. The technology has been readily imbibed by microbiologists who have reported usage of MALDI-TOF MS for a number of purposes like, microbial identification and strain typing, epidemiological studies, detection of biological warfare agents, detection of water- and food-borne pathogens, detection of antibiotic resistance and detection of blood and urinary tract pathogens etc. The limitation of the technology is that identification of new isolates is possible only if the spectral database contains peptide mass fingerprints of the type strains of specific genera/species/subspecies/strains. This review provides an overview of the status and recent applications of mass spectrometry for microbial identification. It also explores the usefulness of this exciting new technology for diagnosis of diseases caused by bacteria, viruses, and fungi.
Introduction: In this work, we target the analysis and the characterization of bioaerosols species present in medical emergency of north Algerian hospital, were we consider in four operating rooms, ...two preoperative and resuscitation rooms.
Materials and methods: Passive technique was applied for the collection of bacterial and fungal samples in indoor air, for three days from 16 to 18 January 2018. Two techniques were then chosen for the bacterial identification, the Analytical Profile Index (API) system and Matrix Assisted Laser Desorption/ Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS).
Results: It has been found that fungal contamination was highest in neurosurgery block, 103 CFU/m3, whereas the highest bacterial contamination, 2645 CFU/m3, was noted in postoperative room. The most predominant identified bacteria were Gram-positive cocci.
Conclusion: The high contamination in bioaerosols and the types of bacteria identified in the premises studied increase the risk of contracting a nosocomial infection, hence the importance of daily disinfection and sterilization of hospitals area in order to reduce bioaerosols dangerous effects on human health.
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•Food processing bacteria were studied using SERS and Raman spectroscopy.•SERS found convincing in acquiring spectral features for bacteria identification.•PCA and PLSDA models were ...found useful in differentiation of bacterial species.
Food processing bacteria play important role in providing flavors, ingredients and other beneficial characteristics to the food but at the same time some bacteria are responsible for food spoilage. Therefore, quick and reliable identification of these food processing bacteria is very necessary for the differentiation between different species which may help in the development of more useful food processing methodologies. In this study, analysis of different bacterial species (Lactobacillus fermentum, Fructobacillus fructosus, Pediococcus pentosaceus and Halalkalicoccus jeotgali) was performed with our in-house developed Ag NPs-based surface-enhanced Raman spectroscopy (SERS) method. The SERS spectral data was analyzed by multivariate data analysis techniques including principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA). Bacterial species were differentiated on the basis of SERS spectral features and potential of SERS was compared with the Raman spectroscopy (RS). SERS along with PCA and PLS-DA was found to be an efficient technique for identification and differentiation of food processing bacterial species. Differentiation with accuracy of 99.5% and sensitivity of 99.7% was depicted by PLS-DA model using leave one out cross validation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•A novel fluorescent sensor array for identification of bacteria based on three kinds of receptors-functionalized CDs synthesized by a one-step method has been developed.•The three ...kinds of receptors (boronic acid, polymixin and vancomycin) give the synthesized CDs the gifts of different binding abilities to bacteria due to the variety of physicochemical nature of different bacteria surfaces.•The proposed fluorescent sensor array has several significant advantages of easy construction, low cost and simple procedure.•The generated fluorescence pattern allowed for the good discrimination of the six kinds of bacteria with 100% correct accuracy and the classification of the bacteria according to the gram status of bacteria.
The identification of bacteria is a crucial issue in the field of medical diagnosis, environmental monitoring and food safety. Conventional methods need long culturing times, highly skilled operators, or recognition elements specific to each kind of the bacteria. Alternatively, sensor arrays offer a cost-effective and simple approach using multiple cross-reactive receptors. Here, a facilely constructed fluorescence sensing array was developed for the identification of various bacteria. The sensor array consists of three facile synthesized carbon dots functionalized with different receptors (boronic acid, polymixin and vancomycin), which could bind to all the bacteria with different affinity instead of a specific one. A unique molecular fingerprint of each kind of bacteria was obtain from the fluorescence response pattern generated from three kinds of carbon dots. By using linear discrimination analysis (LDA) of the response pattern, the effective discrimination of six bacteria studied was demonstrated. The proposed sensor array approach may pave the way for the development of simple, rapid and effective identification of multiplex bioactive samples.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
ABSTRACT
Ventilator-Associated Pneumonia (VAP) is pneumonia in patients who use mechanical ventilator. The empirical antibiotic therapy is given to VAP patients based on bacterial mapping and its ...antibiotic sensitivity. The aim of this study is to determine bacterial identification and antibiotic sensitivity of VAP patients at RSD dr. Soebandi Jember. This study is a retrospective study, the data collected from medical record of VAP patients from September to October 2019. All samples that is meet the inclusion and exclusion criteria was recruited in this study. Data analysis was use Microsoft Excel 2010. This study obtained 15 samples. The most frequents bacteria that causes VAP is Acinetobacter baumanii. It is also caused by Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter aerogenes, Burkholderia cepacia, Pseudomonas fluorescence, Salmonella arizonae, and Escherichia coli. The bacteria are most sensitive to amikacin, meropenem, and piperacillin-tazobactam and most resistant to cefixime, cefotaxime, and ceftriaxone.
Consumption of food contaminated with microorganisms may lead to the public health issue. Therefore, it is important to monitor pathogenic microorganisms at the early stage of production to prevent ...loss in health and economic aspects. In this study, Raman spectroscopic technique was developed to identify food-borne pathogens. The results demonstrated that the variations of each bacterial spectra fingerprint were related to the physiological state of microorganism species. Moreover, the cultivation state of bacteria could affect the identification efficacy by this technique. The spectral ranges of 500–1600 cm−1 were selected to be analyzed with multivariate chemometric analysis and the principal component analysis (PCA) was used to determine optimal parameters for discrimination of food-borne pathogens. Calculated first and second principal components (PC1, PC2) accounted for 51.18 and 48.28% of total variance in the spectra were able to identify the food-borne pathogens at solid and aqueous states. It was clearly demonstrated that suitable cultivation state for microbiological detection by the developed condition was in an aqueous phase. In conclusion, this study suggested that Raman spectroscopy with near-IR wavelength excitation could be potentially useful for the rapid identification of bacteria and possibly applied for food quality control.
•Raman spectroscopy has been developed to identify food-borne pathogens.•Raman scattering coupled with multivariate analysis differentiate bacterial species.•This method could reduce time-consuming and cost by simply using Aluminum materials.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
MALDI-TOF MS is well-recognized for microbial identification and widely used in research and clinical fields due to its specificity, speed of analysis, and low cost of consumables. However, the ...classification or identification accuracy is poor for E. coli and Shigella. In addition, FTIR is a promising tool for bacterial typing. In this study, 14 strains of E. coli and 9 strains of Shigella were typed by both MALDI-TOF MS and FTIR techniques. Alternatively, a data fusion strategy using these two approaches was attempted to achieve better typing accuracy. Hierarchical clustering analysis (HCA) revealed that the typing accuracies for selected E. coli and Shigella from blood agar were 65.2%, 78.3%, and 100% for MALDI-TOF MS, FTIR, and FTIR combined with MALDI-TOF MS, respectively. Based on these results, a library constructed of the MS-IR fusion data was employed to identify individual bacteria at the strain level, and the library-based typing accuracies for 207 test spectra of sample strains from three different culture media yielded 97.6% accuracy for distinguishing between E. coli and Shigella at genus level. For species level and strain level, it yielded 95.2% and 92.3% typing accuracy, respectively. These results indicate that FTIR is a better technique for typing selected E. coli and Shigella than MALDI-TOF MS, and the accuracy is increased by combining the data from MALDI-TOF MS and FTIR spectroscopy. FTIR could be used to supplement MALDI-TOF MS for the identification and typing of taxonomic microorganisms.
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•The classification and typing of E. coli and Shigella by MALDI-TOF MS and FTIR spectroscopy.•The data fusion of MALDI-TOF MS and FTIR spectroscopy increased the bacterial typing accuracy.•FTIR is a better technique for typing of E. coli and Shigella than MALDI-TOF MS at subspecies level.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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