22 results on '"Mathias W. Pletz"'
Search Results
2. Molecular investigations on a chimeric strain of Staphylococcus aureus sequence type 80
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Darius Gawlik, Antje Ruppelt-Lorz, Elke Müller, Annett Reißig, Helmut Hotzel, Sascha D Braun, Bo Söderquist, Albrecht Ziegler-Cordts, Claudia Stein, Mathias W Pletz, Ralf Ehricht, and Stefan Monecke
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Evolutionary Genetics ,Staphylococcus ,Pathology and Laboratory Medicine ,Toxicology ,Enterotoxins ,Mobile Genetic Elements ,Medicine and Health Sciences ,Toxins ,Oligonucleotide Array Sequence Analysis ,Recombination, Genetic ,High-Throughput Nucleotide Sequencing ,Genomics ,Middle Aged ,Staphylococcal Infections ,Bacterial Pathogens ,Medical Microbiology ,Medicine ,Female ,Pathogens ,Research Article ,Staphylococcus aureus ,Science ,Toxic Agents ,Bacterial Toxins ,Research and Analysis Methods ,Microbiology ,Evolution, Molecular ,Genetic Elements ,Bacterial Proteins ,Lymphadenitis ,Genetics ,Humans ,Point Mutation ,Molecular Biology Techniques ,Sequencing Techniques ,Microbial Pathogens ,Molecular Biology ,Evolutionary Biology ,Suppuration ,Bacteria ,Chimera ,Organisms ,Biology and Life Sciences ,Computational Biology ,Sequence Analysis, DNA ,Genome Analysis ,Mutagenesis, Insertional ,Nanopore Sequencing ,Mutation - Abstract
A PVL-positive, methicillin-susceptible Staphylococcus aureus was cultured from pus from cervical lymphadenitis of a patient of East-African origin. Microarray hybridisation assigned the isolate to clonal complex (CC) 80 but revealed unusual features, including the presence of the ORF-CM14 enterotoxin homologue and of an ACME-III element as well as the absence of etD and edinB. The isolate was subjected to both, Illumina and Nanopore sequencing allowing characterisation of deviating regions within the strain´s genome. Atypical features of this strain were attributable to the presence of two genomic regions that originated from other S. aureus lineages and that comprised, respectively, 3% and 1.4% of the genome. One deviating region extended from walJ to sirB. It comprised ORF-CM14 and the ACME-III element. A homologous but larger fragment was also found in an atypical S. aureus CC1/ST567 strain whose lineage might have served as donor of this genomic region. This region itself is a chimera comprising fragments from CC1 as well as fragments of unknown origin. The other deviating region comprised the region from htsB to ecfA2, i.e., another 3% of the genome. It was very similar to CC1 sequences. Either this suggests an incorporation of CC1 DNA into the study strain, or alternatively a recombination event affecting "canonical" CC80. Thus, the study strain bears witness of several recombination events affecting supposedly core genomic genes. Although the exact mechanism is not yet clear, such chimerism seems to be an additional pathway in the evolution of S. aureus. This could facilitate also a transmission of virulence and resistance factors and therefore offer an additional evolutionary advantage.
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- 2020
3. Changes in inflammatory and vasoactive mediator profiles during valvular surgery with or without infective endocarditis: A case control pilot study
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Mahmoud, Diab, Raphael, Tasar, Christoph, Sponholz, Thomas, Lehmann, Mathias W, Pletz, Michael, Bauer, Frank M, Brunkhorst, and Torsten, Doenst
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Male ,Computer and Information Sciences ,Cardiac Surgery ,Cardiovascular Procedures ,Physiology ,Science ,Immunology ,Cardiology ,Pilot Projects ,Surgical and Invasive Medical Procedures ,Pathology and Laboratory Medicine ,Infographics ,Blood Plasma ,Signs and Symptoms ,Diagnostic Medicine ,Immune Physiology ,Medicine and Health Sciences ,Humans ,Immune Response ,Aged ,Inflammation ,Innate Immune System ,Cardiopulmonary Bypass ,Endocarditis ,Data Visualization ,Biology and Life Sciences ,Middle Aged ,Molecular Development ,Heart Valves ,Charts ,Body Fluids ,Blood ,Case-Control Studies ,Immune System ,Cytokines ,Medicine ,Female ,Inflammation Mediators ,Anatomy ,Research Article ,Developmental Biology - Abstract
Background More than 50% of patients with infective endocarditis (IE) develop an indication for surgery. Despite its benefit, surgery is associated with a high incidence of multiple organ dysfunction syndrome (MODS) and mortality, which may be linked to increased release of inflammatory mediators during cardiopulmonary bypass (CPB). We therefore assessed plasma cytokine profiles in patients undergoing valve surgery with or without IE. Methods We performed a prospective case-control pilot study comparing patients undergoing cardiac valve surgery with or without IE. Plasma profiles of inflammatory mediators were measured at 7 defined time points and reported as median (interquartile). The degree of MODS was measured using sequential organ failure assessment (SOFA) score. Results Between May and December 2016 we included 40 patients (20 in each group). Both groups showed similar distribution of age and gender. Patients with IE had higher preoperative SOFA (6.9± 2.6 vs 3.8 ± 1.1, p
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- 2020
4. EBV miRNA expression profiles in different infection stages: A prospective cohort study
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Oliwia Makarewicz, Anne Klink, Karim Kentouche, Matthias Karrasch, Andreas Sauerbrei, Anita Hartung, Renate Egerer, and Mathias W. Pletz
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0301 basic medicine ,Male ,Epstein-Barr Virus Infections ,Herpesvirus 4, Human ,B Cells ,Physiology ,medicine.disease_cause ,Biochemistry ,Pediatrics ,Cohort Studies ,White Blood Cells ,0302 clinical medicine ,Animal Cells ,Gene expression ,Prospective Studies ,Child ,Pathology and laboratory medicine ,Regulation of gene expression ,Multidisciplinary ,Middle Aged ,Medical microbiology ,Viral Load ,Viral Persistence and Latency ,Body Fluids ,Nucleic acids ,Blood ,030220 oncology & carcinogenesis ,Child, Preschool ,Viruses ,Disease Progression ,Medicine ,RNA, Viral ,Female ,Pathogens ,Anatomy ,Cellular Types ,Pediatric Infections ,Viral load ,Research Article ,Adult ,Gene Expression Regulation, Viral ,Herpesviruses ,Adolescent ,Science ,Immune Cells ,Immunology ,Context (language use) ,Biology ,Microbiology ,03 medical and health sciences ,Young Adult ,Virology ,microRNA ,medicine ,Genetics ,Humans ,Epstein-Barr virus ,Non-coding RNA ,Antibody-Producing Cells ,Medicine and health sciences ,Natural antisense transcripts ,Blood Cells ,Biology and life sciences ,Gene Expression Profiling ,Infant, Newborn ,Organisms ,Viral pathogens ,Infant ,Cell Biology ,Epstein–Barr virus ,Gene regulation ,Microbial pathogens ,Gene expression profiling ,MicroRNAs ,030104 developmental biology ,Viral replication ,Case-Control Studies ,RNA ,DNA viruses ,Viral Transmission and Infection - Abstract
The Epstein-Barr virus (EBV) produces different microRNAs (miRNA) with distinct regulatory functions within the infectious cycle. These viral miRNAs regulate the expression of viral and host genes and have been discussed as potential diagnostic markers or even therapeutic targets, provided that the expression profile can be unambiguously correlated to a specific stage of infection or a specific EBV-induced disorder. In this context, miRNA profiling becomes more important since the roles of these miRNAs in the pathogenesis of infections and malignancies are not fully understood. Studies of EBV miRNA expression profiles are sparse and have mainly focused on associated malignancies. This study is the first to examine the miRNA profiles of EBV reactivation and to use a correction step with seronegative patients as a reference. Between 2012 and 2017, we examined the expression profiles of 11 selected EBV miRNAs in 129 whole blood samples from primary infection, reactivation, healthy carriers and EBV seronegative patients. Three of the miRNAs could not be detected in any sample. Other miRNAs showed significantly higher expression levels and prevalence during primary infection than in other stages; miR-BHRF1-1 was the most abundant. The expression profiles from reactivation differed slightly but not significantly from those of healthy carriers, but a specific marker miRNA for each stage could not be identified within the selected EBV miRNA targets.
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- 2018
5. Naso- and oropharyngeal bacterial carriage in nursing home residents: Impact of multimorbidity and functional impairment
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Anja Kwetkat, Wolfgang Pfister, Cornel C. Sieber, Mathias W. Pletz, Diana Pansow, and Heike Hoyer
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Male ,0301 basic medicine ,Pulmonology ,Cross-sectional study ,Staphylococcus ,Oropharynx ,lcsh:Medicine ,Pathology and Laboratory Medicine ,medicine.disease_cause ,0302 clinical medicine ,Risk Factors ,Medizinische Fakultät ,Germany ,Medicine and Health Sciences ,Prevalence ,Public and Occupational Health ,Prospective Studies ,030212 general & internal medicine ,lcsh:Science ,Cognitive Impairment ,Aged, 80 and over ,Multidisciplinary ,Cognitive Neurology ,Incidence (epidemiology) ,Pneumococcus ,Vaccination and Immunization ,Bacterial Pathogens ,Neurology ,Medical Microbiology ,Carrier State ,Female ,Pathogens ,Research Article ,Staphylococcus aureus ,medicine.medical_specialty ,Cognitive Neuroscience ,Immunology ,030106 microbiology ,Nose ,Microbiology ,03 medical and health sciences ,Internal medicine ,Streptococcus pneumoniae ,Escherichia coli ,medicine ,Humans ,ddc:610 ,Risk factor ,Microbial Pathogens ,Gram Negative Bacteria ,Aged ,Bacteria ,business.industry ,lcsh:R ,Organisms ,Biology and Life Sciences ,Streptococcus ,Multimorbidity ,Bacteriology ,Pneumonia ,Odds ratio ,medicine.disease ,Comorbidity ,Nursing Homes ,Health Care ,Cross-Sectional Studies ,Logistic Models ,Carriage ,Health Care Facilities ,Cognitive Science ,lcsh:Q ,Preventive Medicine ,business ,Neuroscience - Abstract
Objective From April 2013 to February 2014 we performed a multicentre prospective cross-sectional study in 541 German nursing home residents. We determined pharyngeal carriage of Streptococcus pneumoniae (primary objective) and other bacteria (secondary objective) in naso- and oropharyngeal swabs by culture-based standard procedures and explored the influence of multimorbidity and functional status on bacterial carriage. Methods Socio-demographic data, vaccination status, multimorbidity, nutrition and functional status defined by Comprehensive Geriatric Assessment were evaluated. We estimated carriage rates with 95% confidence intervals (CI) and explored potential risk factors by logistic regression analysis. Results Pneumococcal post-serotyping carriage rate was 0.8% (95%CI 0.2–1.9%; 4/526). Serotyping revealed serotypes 4, 7F, 23B and 23F and S. pseudopneumoniae in two other cases. Odds of carriage were higher in men (Odds ratio OR 5.3 (95%CI 0.9–29.4)), in malnourished residents (OR 4.6 (0.8–25.7)), residents living in shared rooms (OR 3.0 (0.5–16.5)) or having contact with schoolchildren (OR 2.0 (0.2–17.6)). The most frequent pathogen was Staphylococcus aureus (prevalence 29.5% (25.6–33.6%)) with meticillin-resistant Staphylococcus aureus prevalence of 1.1%. Gram-negative bacteria (GNB) were found in 22.5% (19.0–26.3%) with a prevalence of extended-spectrum beta lactamase (ESBL) producing bacteria of 0.8%. Odds of S. aureus carriage were higher for immobility (OR 1.84 (1.15–2.93)) and cognitive impairment (OR 1.54 (0.98–2.40)). Odds of GNB carriage were higher in residents with more severe comorbidity (OR 1.13 (1.00–1.28)) and malnutrition (OR 1.54 (0.81–2.91)). Conclusions Given the observed data, at least long-term carriage of S. pneumoniae in nursing home residents seems to be rare and rather unlikely to cause nursing home acquired pneumonia. The low rate of colonization with multi drug resistant (MDR) bacteria confirms that nursing home residency is not a risk factor for MDR pneumonia in Germany. For individual risk assessment in this susceptible population, immobility and malnutrition should be considered as signs of functional impairment as well as comorbidity.
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- 2018
6. ESBL colonization and acquisition in a hospital population: The molecular epidemiology and transmission of resistance genes
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Vladimir Patchev, Mathias W. Pletz, Anita Hartung, Stefan Hagel, Oliwia Makarewicz, Ralf Ehricht, Christian Brandt, Ulrike Schumacher, Daniel Weiß, and Claudia Stein
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Bacterial Diseases ,0301 basic medicine ,Nosocomial Infections ,Epidemiology ,Microarrays ,Klebsiella pneumoniae ,Antibiotics ,Colony Count, Microbial ,Drug resistance ,Pathology and Laboratory Medicine ,Klebsiella Pneumoniae ,Patient Admission ,0302 clinical medicine ,Risk Factors ,Klebsiella ,Medicine and Health Sciences ,Medicine ,Colonization ,030212 general & internal medicine ,Prospective cohort study ,Molecular Epidemiology ,Multidisciplinary ,biology ,Antimicrobials ,Transmission (medicine) ,Enterobacteriaceae Infections ,Drugs ,Hospitals ,Patient Discharge ,Bacterial Pathogens ,Infectious Diseases ,Bioassays and Physiological Analysis ,Medical Microbiology ,Enterobacter Infections ,Pathogens ,Plasmids ,Research Article ,medicine.medical_specialty ,medicine.drug_class ,Science ,030106 microbiology ,Surgical and Invasive Medical Procedures ,Research and Analysis Methods ,Microbiology ,beta-Lactamases ,03 medical and health sciences ,Enterobacteriaceae ,Microbial Control ,Internal medicine ,Drug Resistance, Bacterial ,Humans ,Microbial Pathogens ,Pharmacology ,Bacteria ,Molecular epidemiology ,business.industry ,Organisms ,Biology and Life Sciences ,biology.organism_classification ,Health Care ,Clinical trial ,Genes, Bacterial ,Health Care Facilities ,Medical Risk Factors ,business ,Follow-Up Studies - Abstract
A prospective cohort study (German Clinical Trial Registry, No. 00005273) was performed to determine pre-admission colonization rates, hospital acquisition risk factors, subsequent infection rates and colonization persistence including the respective molecular epidemiology and transmission rates of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (EPE). A total of 342 EPEs were isolated from rectal swabs of 1,334 patients on admission, at discharge and 6 months after hospitalization. Inclusion criteria were patients’ age > 18 years, expected length of stays > 48 hours, external referral. The EPEs were characterized by routine microbiological methods, a DNA microarray and ERIC-PCR. EPE colonization was found in 12.7 % of admitted patients, with the highest rate (23.8 %) in patients from nursing homes. During hospitalization, 8.1 % of the patients were de novo EPE colonized, and invasive procedures, antibiotic and antacid therapies were independent risk factors. Only 1/169 patients colonized on admission developed a hospital-acquired EPE infection. Escherichia coli was the predominant EPE (88.9 %), and 92.1% of the ESBL phenotypes could be related to CTX-M variants with CTX-M-1/15 group being most frequent (88.9%). A corresponding β-lactamase could not be identified in five isolates. Hospital-acquired EPE infections in patients colonized before or during hospitalization were rare. The diversity of the EPE strains was much higher than that of the underlying plasmids. In seven patients, transmission of the respective plasmid across different species could be observed indicating that the current strain-based surveillance approaches may underestimate the risk of inter-species transmission of resistance genes.
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- 2019
7. A Novel Computerized Cell Count Algorithm for Biofilm Analysis
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Oliwia Makarewicz, Mathias W. Pletz, Dagmar Fischer, Herbert Suesse, and Mareike Klinger-Strobel
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0301 basic medicine ,Confocal Microscopy ,Antibiotics ,lcsh:Medicine ,Cell Count ,medicine.disease_cause ,Pathology and Laboratory Medicine ,chemistry.chemical_compound ,Medicine and Health Sciences ,lcsh:Science ,Staining ,Microscopy ,Multidisciplinary ,Antimicrobials ,Applied Mathematics ,Simulation and Modeling ,Drugs ,Light Microscopy ,Pseudomonas Aeruginosa ,Crystal Violet Staining ,Plankton ,Anti-Bacterial Agents ,Bacterial Pathogens ,Medical Microbiology ,Physical Sciences ,Pathogens ,Algorithm ,Algorithms ,medicine.drug ,Research Article ,medicine.drug_class ,030106 microbiology ,Cell Enumeration Techniques ,Microbial Sensitivity Tests ,Biology ,Research and Analysis Methods ,Microbiology ,03 medical and health sciences ,Minimum inhibitory concentration ,Microbial Control ,Pseudomonas ,Viable Cell Counting ,medicine ,Computer Simulation ,Microbial Pathogens ,Pharmacology ,Bacteria ,Pseudomonas aeruginosa ,Colistin ,lcsh:R ,Biofilm ,Organisms ,Biology and Life Sciences ,Bacteriology ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,030104 developmental biology ,Nitroxoline ,chemistry ,Specimen Preparation and Treatment ,Biofilms ,lcsh:Q ,Bacterial Biofilms ,Confocal Laser Microscopy ,Mathematics - Abstract
Biofilms are the preferred sessile and matrix-embedded life form of most microorganisms on surfaces. In the medical field, biofilms are a frequent cause of treatment failure because they protect the bacteria from antibiotics and immune cells. Antibiotics are selected according to the minimal inhibitory concentration (MIC) based on the planktonic form of bacteria. Determination of the minimal biofilm eradicating concentration (MBEC), which can be up to 1,000-fold greater than the MIC, is not currently conducted as routine diagnostic testing, primarily because of the methodical hurdles of available biofilm assessing protocols that are time- and cost-consuming. Comparative analysis of biofilms is also limited as most quantitative methods such as crystal violet staining are indirect and highly imprecise. In this paper, we present a novel algorithm for assessing biofilm resistance to antibiotics that overcomes several of the limitations of alternative methods. This algorithm aims for a computer-based analysis of confocal microscope 3D images of biofilms after live/dead stains providing various biofilm parameters such as numbers of viable and dead cells and their vertical distributions within the biofilm, or biofilm thickness. The performance of this algorithm was evaluated using computer-simulated 2D and 3D images of coccal and rodent cells varying different parameters such as cell density, shading or cell size. Finally, genuine biofilms that were untreated or treated with nitroxoline or colistin were analyzed and the results were compared with quantitative microbiological standard methods. This novel algorithm allows a direct, fast and reproducible analysis of biofilms after live/dead staining. It performed well in biofilms of moderate cell densities in a 2D set-up however the 3D analysis remains still imperfect and difficult to evaluate. Nevertheless, this is a first try to develop an easy but conclusive tool that eventually might be implemented into routine diagnostics to determine the MBEC and to improve outcomes of patients with biofilm-associated infections.
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- 2015
8. Three Dimensional Checkerboard Synergy Analysis of Colistin, Meropenem, Tigecycline against Multidrug-Resistant Clinical Klebsiella pneumonia Isolates
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Mathias W. Pletz, Jürgen A. Bohnert, Miriam Kesselmeier, Oliwia Makarewicz, Stefan Hagel, Claudia Stein, and Yvonne Pfeifer
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Carbapenem ,Klebsiella pneumoniae ,medicine.drug_class ,Antibiotics ,lcsh:Medicine ,Porins ,Minocycline ,Tigecycline ,Microbial Sensitivity Tests ,Meropenem ,Microbiology ,Antibiotic resistance ,Bacterial Proteins ,Drug Resistance, Multiple, Bacterial ,medicine ,polycyclic compounds ,lcsh:Science ,Multidisciplinary ,biology ,Colistin ,lcsh:R ,Drug Synergism ,Gene Expression Regulation, Bacterial ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,medicine.disease ,bacterial infections and mycoses ,Anti-Bacterial Agents ,bacteria ,lcsh:Q ,Thienamycins ,Klebsiella pneumonia ,medicine.drug ,Research Article - Abstract
The spread of carbapenem-non-susceptible Klebsiella pneumoniae strains bearing different resistance determinants is a rising problem worldwide. Especially infections with KPC (Klebsiella pneumoniae carbapenemase) - producers are associated with high mortality rates due to limited treatment options. Recent clinical studies of KPC-blood stream infections revealed that colistin-based combination therapy with a carbapenem and/or tigecycline was associated with significantly decreased mortality rates when compared to colistin monotherapy. However, it remains unclear if these observations can be transferred to K. pneumoniae harboring other mechanisms of carbapenem resistance. A three-dimensional synergy analysis was performed to evaluate the benefits of a triple combination with meropenem, tigecycline and colistin against 20 K. pneumoniae isolates harboring different β-lactamases. To examine the mechanism behind the clinically observed synergistic effect, efflux properties and outer membrane porin (Omp) genes (ompK35 and ompK36) were also analyzed. Synergism was found for colistin-based double combinations for strains exhibiting high minimal inhibition concentrations against all of the three antibiotics. Adding a third antibiotic did not result in further increased synergistic effect in these strains. Antagonism did not occur. These results support the idea that colistin-based double combinations might be sufficient and the most effective combination partner for colistin should be chosen according to its MIC.
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- 2015
9. Detection of pneumonia associated pathogens using a prototype multiplexed pneumonia test in hospitalized patients with severe pneumonia
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Matthias Klein, Anne Thews, Sandrine Roisin, Catia Cilloniz, Holm Eickmeyer, Berit Schulte, Antoni Torres, Sandra Barth, Mathias W. Pletz, Eberhard Straube, Alexandra Heininger, Gerd Lüdke, Olivier Denis, Ingo B. Autenrieth, Stephanie Juretzek, Matthias Karrasch, Peter M. Keller, and Universitat de Barcelona
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Male ,Bacterial Diseases ,Hospitalized patients ,Epidemiology ,Antibiotics ,Psychologie appliquée ,lcsh:Medicine ,Pneumònia ,Pathology and Laboratory Medicine ,Pneumònia adquirida a la comunitat ,Hospital patients ,law.invention ,0302 clinical medicine ,law ,Reacció en cadena de la polimerasa ,Medicine and Health Sciences ,Medicine ,030212 general & internal medicine ,Diagnostic microbiology ,lcsh:Science ,Polymerase chain reaction ,Aged, 80 and over ,0303 health sciences ,Multidisciplinary ,Time to result ,Middle Aged ,Sciences bio-médicales et agricoles ,3. Good health ,Hospitalization ,Infectious Diseases ,Female ,Biologie ,Research Article ,Adult ,medicine.medical_specialty ,Clinical Pathology ,Community-acquired pneumonia ,medicine.drug_class ,Diagnòstic microbiològic ,Young Adult ,03 medical and health sciences ,Diagnostic Medicine ,Internal medicine ,Multiplex polymerase chain reaction ,Humans ,In patient ,Epidemiologia ,Aged ,Malalts hospitalitzats ,Bacteria ,030306 microbiology ,business.industry ,lcsh:R ,Pneumonia ,medicine.disease ,Confidence interval ,Surgery ,Clinical Microbiology ,Bacterial Pneumonia ,lcsh:Q ,business ,Multiplex Polymerase Chain Reaction - Abstract
Severe pneumonia remains an important cause of morbidity and mortality. Polymerase chain reaction (PCR) has been shown to be more sensitive than current standard microbiological methods - particularly in patients with prior antibiotic treatment - and therefore, may improve the accuracy of microbiological diagnosis for hospitalized patients with pneumonia. Conventional detection techniques and multiplex PCR for 14 typical bacterial pneumonia-associated pathogens were performed on respiratory samples collected from adult hospitalized patients enrolled in a prospective multi-center study. Patients were enrolled from March until September 2012. A total of 739 fresh, native samples were eligible for analysis, of which 75 were sputa, 421 aspirates, and 234 bronchial lavages. 276 pathogens were detected by microbiology for which a valid PCR result was generated (positive or negative detection result by Curetis prototype system). Among these, 120 were identified by the prototype assay, 50 pathogens were not detected. Overall performance of the prototype for pathogen identification was 70.6% sensitivity (95% confidence interval (CI) lower bound: 63.3%, upper bound: 76.9%) and 95.2% specificity (95% CI lower bound: 94.6%, upper bound: 95.7%). Based on the study results, device cut-off settings were adjusted for future series production. The overall performance with the settings of the CE series production devices was 78.7% sensitivity (95% CI lower bound: 72.1%) and 96.6% specificity (95% CI lower bound: 96.1%). Time to result was 5.2 hours (median) for the prototype test and 43.5 h for standard-of-care. The Pneumonia Application provides a rapid and moderately sensitive assay for the detection of pneumonia-causing pathogens with minimal hands-on time., SCOPUS: ar.j, info:eu-repo/semantics/published
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- 2014
10. Rapid identification of carbapenemase genes in gram-negative bacteria with an oligonucleotide microarray-based assay
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Peter Slickers, Annett Reißig, Oliwia Makarewicz, Stefan Monecke, Mathias W. Pletz, Antje Ruppelt, Ralf Ehricht, Sascha D. Braun, and Alexander Thürmer
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Klebsiella pneumoniae ,lcsh:Medicine ,medicine.disease_cause ,Microbiology ,beta-Lactamases ,law.invention ,Bacterial Proteins ,law ,Microbial Control ,Gram-Negative Bacteria ,medicine ,lcsh:Science ,Polymerase chain reaction ,Oligonucleotide Array Sequence Analysis ,Multidisciplinary ,Microbial Drug Resistance ,biology ,Pseudomonas aeruginosa ,lcsh:R ,Citrobacter braakii ,Biology and Life Sciences ,Klebsiella oxytoca ,Enterobacter ,biology.organism_classification ,Citrobacter freundii ,Acinetobacter baumannii ,lcsh:Q ,Research Article - Abstract
Rapid molecular identification of carbapenemase genes in Gram-negative bacteria is crucial for infection control and prevention, surveillance and for epidemiological purposes. Furthermore, it may have a significant impact upon determining the appropriate initial treatment and greatly benefit for critically ill patients. A novel oligonucleotide microarray-based assay was developed to simultaneously detect genes encoding clinically important carbapenemases as well as selected extended (ESBL) and narrow spectrum (NSBL) beta-lactamases directly from clonal culture material within few hours. Additionally, a panel of species specific markers was included to identify Escherichia coli, Pseudomonas aeruginosa, Citrobacter freundii/braakii, Klebsiella pneumoniae and Acinetobacter baumannii. The assay was tested using a panel of 117 isolates collected from urinary, blood and stool samples. For these isolates, phenotypic identifications and susceptibility tests were available. An independent detection of carbapenemase, ESBL and NSBL genes was carried out by various external reference laboratories using PCR methods. In direct comparison, the microarray correctly identified 98.2% of the covered carbapenemase genes. This included blaVIM (13 out of 13), blaGIM (2/2), blaKPC (27/27), blaNDM (5/5), blaIMP-2/4/7/8/13/14/15/16/31 (10/10), blaOXA-23 (12/13), blaOXA-40-group (7/7), blaOXA-48-group (32/33), blaOXA-51 (1/1) and blaOXA-58 (1/1). Furthermore, the test correctly identified additional beta-lactamases [blaOXA-1 (16/16), blaOXA-2 (4/4), blaOXA-9 (33/33), OXA-10 (3/3), blaOXA-51 (25/25), blaOXA-58 (2/2), CTX-M1/M15 (17/17) and blaVIM (1/1)]. In direct comparison to phenotypical identification obtained by VITEK or MALDI-TOF systems, 114 of 117 (97.4%) isolates, including Acinetobacter baumannii (28/28), Enterobacter spec. (5/5), Escherichia coli (4/4), Klebsiella pneumoniae (62/63), Klebsiella oxytoca (0/2), Pseudomonas aeruginosa (12/12), Citrobacter freundii (1/1) and Citrobacter braakii (2/2), were correctly identified by a panel of species specific probes. This assay might be easily extended, adapted and transferred to point of care platforms enabling fast surveillance, rapid detection and appropriate early treatment of infections caused by multiresistant Gram-negative bacteria.
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- 2014
11. Evaluation of a Polymerase Chain Reaction Assay for Pathogen Detection in Septic Patients under Routine Condition: An Observational Study
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Andreas Kortgen, Konrad Reinhart, Svea Sachse, Michael Bauer, Mathias W. Pletz, Niels C. Riedemann, Eberhard Straube, Marc Lehmann, and Frank Bloos
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Bacterial Diseases ,Male ,Critical Care and Emergency Medicine ,Applied Microbiology ,lcsh:Medicine ,Biochemistry ,Procalcitonin ,Medical microbiology ,DNA amplification ,Interquartile range ,Blood culture ,lcsh:Science ,DNA, Fungal ,Multidisciplinary ,medicine.diagnostic_test ,Fungal Diseases ,Middle Aged ,Antimicrobial ,Bacterial Pathogens ,Anti-Bacterial Agents ,Nucleic acids ,Infectious Diseases ,Medical Microbiology ,Observational Studies ,Medicine ,Female ,Research Article ,DNA, Bacterial ,medicine.medical_specialty ,Infectious Disease Control ,Clinical Research Design ,Biology ,Microbiology ,Sepsis ,Diagnostic Medicine ,Internal medicine ,Multiplex polymerase chain reaction ,medicine ,Humans ,Aged ,Bacteria ,Septic shock ,lcsh:R ,Fungi ,DNA ,medicine.disease ,Surgery ,lcsh:Q ,Multiplex Polymerase Chain Reaction - Abstract
BACKGROUND: Treatment of septic shock relies on appropriate antimicrobial therapy. Current culture based methods deliver final results after days, which may delay potentially lifesaving adjustments in antimicrobial therapy. This study was undertaken to compare PCR with blood culture results under routine conditions regarding 1. impact on antimicrobial therapy, and 2. time to result, in patients with presumed sepsis. METHODOLOGY/PRINCIPAL FINDINGS: This was an observational study in a 50 beds ICU of a university hospital. In 245 patients with suspected sepsis, 311 concomitant blood cultures and blood for multiplex PCR (VYOO(®)) were obtained. 45 of 311 blood cultures (14.5%) and 94 of 311 PCRs (30.1%) were positive. However, blood culture or microbiological sampling from the presumed site of infection rarely confirmed PCR results and vice versa. Median time to positivity and interquartile range were 24.2 (18.0, 27.5) hours for the PCR and 68 (52.2, 88.5) hours for BC (p
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- 2012
12. Direct RNA-Based Detection and Differentiation of CTX-M-Type Extended-Spectrum β-Lactamases (ESBL)
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Christian Brandt, Yvonne Pfeifer, João M. Costa Ramos, Mathias W. Pletz, Mareike Klinger, Oliwia Makarewicz, and Claudia Stein
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Klebsiella pneumoniae ,Science ,Real-Time Polymerase Chain Reaction ,medicine.disease_cause ,beta-Lactamases ,law.invention ,law ,Escherichia coli ,medicine ,Gene ,Polymerase chain reaction ,Genetics ,Multidisciplinary ,biology ,RNA ,Reverse Transcription ,biology.organism_classification ,Reverse transcriptase ,Real-time polymerase chain reaction ,Mutation ,Medicine ,Pyrosequencing ,Research Article - Abstract
The current global spread of multi-resistant Gram-negatives, particularly extended spectrum β-lactamases expressing bacteria, increases the likelihood of inappropriate empiric treatment of critically ill patients with subsequently increased mortality. From a clinical perspective, fast detection of resistant pathogens would allow a pre-emptive correction of an initially inappropriate treatment. Here we present diagnostic amplification-sequencing approach as proof of principal based on the fast molecular detection and correct discrimination of CTX-M-β-lactamases, the most frequent ESBL family. The workflow consists of the isolation of total mRNA and CTX-M-specific reverse transcription (RT), amplification and pyrosequencing. Due to the high variability of the CTX-M-β-lactamase-genes, degenerated primers for RT, qRT as well as for pyrosequencing, were used and the suitability and discriminatory performance of two conserved positions within the CTX-M genes were analyzed, using one protocol for all isolates and positions, respectively. Using this approach, no information regarding the expected CTX-M variant is needed since all sequences are covered by these degenerated primers. The presented workflow can be conducted within eight hours and has the potential to be expanded to other β-lactamase families.
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- 2013
13. Bronchiectasis-Associated Hospitalizations in Germany, 2005–2011: A Population-Based Study of Disease Burden and Trends
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Felix C. Ringshausen, Nina Hämäläinen, Tobias Welte, Mathias W. Pletz, Andrés de Roux, and Jessica Rademacher
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Male ,Bacterial Diseases ,Pediatrics ,Non-Clinical Medicine ,Pulmonology ,Chronic Obstructive Pulmonary Diseases ,Epidemiology ,Prevalence ,lcsh:Medicine ,Cost of Illness ,Germany ,Health care ,Clinical Epidemiology ,lcsh:Science ,Aged, 80 and over ,COPD ,education.field_of_study ,Multidisciplinary ,Nontuberculous Mycobacteria ,Mycobacterium Avium Complex ,Patient Discharge ,Bronchiectasis ,Hospitalization ,Lower Respiratory Tract Infections ,Infectious Diseases ,Medicine ,Female ,Research Article ,medicine.medical_specialty ,Clinical Research Design ,Population ,Infectious Disease Epidemiology ,Mycobacterium ,medicine ,Humans ,Pseudomonas Infections ,education ,Disease burden ,Aged ,Health Care Policy ,business.industry ,lcsh:R ,Length of Stay ,medicine.disease ,Pneumonia ,Respiratory Infections ,lcsh:Q ,Health Statistics ,business - Abstract
Background Representative population-based data on the epidemiology of bronchiectasis in Europe are limited. The aim of the present study was to investigate the current burden and the trends of bronchiectasis-associated hospitalizations and associated conditions in Germany in order to inform focused patient care and to facilitate the allocation of healthcare resources. Methods The nationwide diagnosis-related groups hospital statistics for the years 2005–2011 were used in order to identify hospitalizations with bronchiectasis as any hospital discharge diagnosis according to the International Classification of Diseases, 10th revision, code J47, (acquired) bronchiectasis. Poisson log-linear regression analysis was used to assess the significance of trends. In addition, the overall length of hospital stay (LOS) and the in-hospital mortality in comparison to the nationwide overall mortality due to bronchiectasis as the primary diagnosis was assessed. Results Overall, 61,838 records with bronchiectasis were extracted from more than 125 million hospitalizations. The average annual age-adjusted rate for bronchiectasis as any diagnosis was 9.4 hospitalizations per 100,000 population. Hospitalization rates increased significantly during the study period, with the highest rate of 39.4 hospitalizations per 100,000 population among men aged 75–84 years and the most pronounced average annual increases among females. Besides numerous bronchiectasis-associated conditions, chronic obstructive pulmonary disease (COPD) was most frequently found in up to 39.2% of hospitalizations with bronchiectasis as the primary diagnosis. The mean LOS was comparable to that for COPD. Overall, only 40% of bronchiectasis-associated deaths occurred inside the hospital. Conclusions The present study provides evidence of a changing epidemiology and a steadily increasing prevalence of bronchiectasis-associated hospitalizations. Moreover, it confirms the diversity of bronchiectasis-associated conditions and the possible association between bronchiectasis and COPD. As the major burden of disease may be managed out-of-hospital, prospective patient registries are needed to establish the exact prevalence of bronchiectasis according to the specific underlying condition.
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- 2013
14. Public health risk communication through the lens of a quarantined community: Insights from a coronavirus hotspot in Germany.
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Annika Licht, Wibke Wetzker, Juliane Scholz, André Scherag, Sebastian Weis, Mathias W Pletz, Michael Bauer, Petra Dickmann, and CoNAN study group
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Medicine ,Science - Abstract
BackgroundQuarantine is one of the most effective interventions to contain an infectious disease outbreak, yet it is one of the most disruptive. We investigated the quarantine of an entire village to better understand risk communication requirements for groups.MethodsWe conducted a cross-sectional, mixed-methods survey study on a single cohort of adult residents in Neustadt am Rennsteig, Germany, six weeks after the removal of a 14-day mandatory community quarantine. The survey response rate was 33% (289/883 residents).FindingsSurvey participants reported a lack of information on the quarantine implementation process. What authorities communicated was not necessarily what residents desired to know. While inhabitants used social media and telephones to communicate with each other, the official information sources were regional radio, television, newspapers and official websites. Public health authorities did not employ social media communication to engage with their communities. Despite a lack of information, the majority of respondents stated that they had complied with the quarantine and they expressed little sympathy for those who violated the quarantine. After lifting the quarantine, many respondents continued to avoid places where they suspected a significant risk of infection, such as family and friends' homes, doctor's offices and grocery stores.InterpretationThe survey participants utilised existing social networks to disseminate vital information and stabilise its group identity and behaviour (quarantine compliance). The authorities communicated sparsely in a unidirectional, top-down manner, without engaging the community. Despite the lack of official information, the social coherency of the group contributed to considerate and compliant conduct, but participants expressed dissatisfaction with official leadership and asked for more attention.ConclusionPublic health risk communication must engage with communities more effectively. This necessitates a deeper comprehension of groups, their modes of communication and their social needs.
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- 2023
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15. EBV miRNA expression profiles in different infection stages: A prospective cohort study.
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Anita Hartung, Oliwia Makarewicz, Renate Egerer, Matthias Karrasch, Anne Klink, Andreas Sauerbrei, Karim Kentouche, and Mathias W Pletz
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Medicine ,Science - Abstract
The Epstein-Barr virus (EBV) produces different microRNAs (miRNA) with distinct regulatory functions within the infectious cycle. These viral miRNAs regulate the expression of viral and host genes and have been discussed as potential diagnostic markers or even therapeutic targets, provided that the expression profile can be unambiguously correlated to a specific stage of infection or a specific EBV-induced disorder. In this context, miRNA profiling becomes more important since the roles of these miRNAs in the pathogenesis of infections and malignancies are not fully understood. Studies of EBV miRNA expression profiles are sparse and have mainly focused on associated malignancies. This study is the first to examine the miRNA profiles of EBV reactivation and to use a correction step with seronegative patients as a reference. Between 2012 and 2017, we examined the expression profiles of 11 selected EBV miRNAs in 129 whole blood samples from primary infection, reactivation, healthy carriers and EBV seronegative patients. Three of the miRNAs could not be detected in any sample. Other miRNAs showed significantly higher expression levels and prevalence during primary infection than in other stages; miR-BHRF1-1 was the most abundant. The expression profiles from reactivation differed slightly but not significantly from those of healthy carriers, but a specific marker miRNA for each stage could not be identified within the selected EBV miRNA targets.
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- 2019
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16. ESBL colonization and acquisition in a hospital population: The molecular epidemiology and transmission of resistance genes.
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Stefan Hagel, Oliwia Makarewicz, Anita Hartung, Daniel Weiß, Claudia Stein, Christian Brandt, Ulrike Schumacher, Ralf Ehricht, Vladimir Patchev, and Mathias W Pletz
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Medicine ,Science - Abstract
A prospective cohort study (German Clinical Trial Registry, No. 00005273) was performed to determine pre-admission colonization rates, hospital acquisition risk factors, subsequent infection rates and colonization persistence including the respective molecular epidemiology and transmission rates of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (EPE). A total of 342 EPEs were isolated from rectal swabs of 1,334 patients on admission, at discharge and 6 months after hospitalization. Inclusion criteria were patients' age > 18 years, expected length of stays > 48 hours, external referral. The EPEs were characterized by routine microbiological methods, a DNA microarray and ERIC-PCR. EPE colonization was found in 12.7 % of admitted patients, with the highest rate (23.8 %) in patients from nursing homes. During hospitalization, 8.1 % of the patients were de novo EPE colonized, and invasive procedures, antibiotic and antacid therapies were independent risk factors. Only 1/169 patients colonized on admission developed a hospital-acquired EPE infection. Escherichia coli was the predominant EPE (88.9 %), and 92.1% of the ESBL phenotypes could be related to CTX-M variants with CTX-M-1/15 group being most frequent (88.9%). A corresponding β-lactamase could not be identified in five isolates. Hospital-acquired EPE infections in patients colonized before or during hospitalization were rare. The diversity of the EPE strains was much higher than that of the underlying plasmids. In seven patients, transmission of the respective plasmid across different species could be observed indicating that the current strain-based surveillance approaches may underestimate the risk of inter-species transmission of resistance genes.
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- 2019
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17. Whole Genome Sequencing of 39 Invasive Streptococcus pneumoniae Sequence Type 199 Isolates Revealed Switches from Serotype 19A to 15B.
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Oliwia Makarewicz, Marie Lucas, Christian Brandt, Leonie Herrmann, Andreas Albersmeier, Christian Rückert, Jochen Blom, Alexander Goesmann, Mark van der Linden, Jörn Kalinowski, and Mathias W Pletz
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Medicine ,Science - Abstract
Streptococcus pneumoniae is a major pathogen that causes different invasive pneumococcal diseases (IPD). The pneumococcal polysaccharide capsule is a main virulence factor. More than 94 capsule types have been described, but only a limited number of capsule types accounted for the majority of IPD cases before the introduction of pneumococcal vaccines. After the introduction of the conjugated pneumococcal vaccine PCV7, which covered the seven most frequent serotypes in IPD in the USA, an increase in IPD caused by non-vaccine serotypes was observed, and serotype 19A, which belongs to sequence type (ST) 199, was among the most prevalent STs. After the introduction of the extended vaccine PCV13, which includes serotype 19A, serogroup 15B/C increased in IPD. Therefore, whole genome sequences of 39 isolates of ST199 from Germany (collected between 1998 and 2011) with serotype 19A (n = 24) and serogroup 15B/C (n = 15) were obtained using an Illumina platform and were analysed to identify capsular switches within ST199. Two 19A to 15B/C serotype switch events were identified. Both events occurred before the introduction of PCV7, which indicates that a capsular switch from 19A to 15B among ST199 isolates is not unusual and is not directly linked to the vaccination. The observed serotype replacement appears to be the result of a vacant niche due to the displacement of vaccine serotypes that is now successfully occupied by ST199 clones.
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- 2017
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18. A Novel Computerized Cell Count Algorithm for Biofilm Analysis.
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Mareike Klinger-Strobel, Herbert Suesse, Dagmar Fischer, Mathias W Pletz, and Oliwia Makarewicz
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Medicine ,Science - Abstract
Biofilms are the preferred sessile and matrix-embedded life form of most microorganisms on surfaces. In the medical field, biofilms are a frequent cause of treatment failure because they protect the bacteria from antibiotics and immune cells. Antibiotics are selected according to the minimal inhibitory concentration (MIC) based on the planktonic form of bacteria. Determination of the minimal biofilm eradicating concentration (MBEC), which can be up to 1,000-fold greater than the MIC, is not currently conducted as routine diagnostic testing, primarily because of the methodical hurdles of available biofilm assessing protocols that are time- and cost-consuming. Comparative analysis of biofilms is also limited as most quantitative methods such as crystal violet staining are indirect and highly imprecise. In this paper, we present a novel algorithm for assessing biofilm resistance to antibiotics that overcomes several of the limitations of alternative methods. This algorithm aims for a computer-based analysis of confocal microscope 3D images of biofilms after live/dead stains providing various biofilm parameters such as numbers of viable and dead cells and their vertical distributions within the biofilm, or biofilm thickness. The performance of this algorithm was evaluated using computer-simulated 2D and 3D images of coccal and rodent cells varying different parameters such as cell density, shading or cell size. Finally, genuine biofilms that were untreated or treated with nitroxoline or colistin were analyzed and the results were compared with quantitative microbiological standard methods. This novel algorithm allows a direct, fast and reproducible analysis of biofilms after live/dead staining. It performed well in biofilms of moderate cell densities in a 2D set-up however the 3D analysis remains still imperfect and difficult to evaluate. Nevertheless, this is a first try to develop an easy but conclusive tool that eventually might be implemented into routine diagnostics to determine the MBEC and to improve outcomes of patients with biofilm-associated infections.
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- 2016
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19. Three Dimensional Checkerboard Synergy Analysis of Colistin, Meropenem, Tigecycline against Multidrug-Resistant Clinical Klebsiella pneumonia Isolates.
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Claudia Stein, Oliwia Makarewicz, Jürgen A Bohnert, Yvonne Pfeifer, Miriam Kesselmeier, Stefan Hagel, and Mathias W Pletz
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Medicine ,Science - Abstract
The spread of carbapenem-non-susceptible Klebsiella pneumoniae strains bearing different resistance determinants is a rising problem worldwide. Especially infections with KPC (Klebsiella pneumoniae carbapenemase) - producers are associated with high mortality rates due to limited treatment options. Recent clinical studies of KPC-blood stream infections revealed that colistin-based combination therapy with a carbapenem and/or tigecycline was associated with significantly decreased mortality rates when compared to colistin monotherapy. However, it remains unclear if these observations can be transferred to K. pneumoniae harboring other mechanisms of carbapenem resistance. A three-dimensional synergy analysis was performed to evaluate the benefits of a triple combination with meropenem, tigecycline and colistin against 20 K. pneumoniae isolates harboring different β-lactamases. To examine the mechanism behind the clinically observed synergistic effect, efflux properties and outer membrane porin (Omp) genes (ompK35 and ompK36) were also analyzed. Synergism was found for colistin-based double combinations for strains exhibiting high minimal inhibition concentrations against all of the three antibiotics. Adding a third antibiotic did not result in further increased synergistic effect in these strains. Antagonism did not occur. These results support the idea that colistin-based double combinations might be sufficient and the most effective combination partner for colistin should be chosen according to its MIC.
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- 2015
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20. Detection of pneumonia associated pathogens using a prototype multiplexed pneumonia test in hospitalized patients with severe pneumonia.
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Berit Schulte, Holm Eickmeyer, Alexandra Heininger, Stephanie Juretzek, Matthias Karrasch, Olivier Denis, Sandrine Roisin, Mathias W Pletz, Matthias Klein, Sandra Barth, Gerd H Lüdke, Anne Thews, Antoni Torres, Catia Cillóniz, Eberhard Straube, Ingo B Autenrieth, and Peter M Keller
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Medicine ,Science - Abstract
Severe pneumonia remains an important cause of morbidity and mortality. Polymerase chain reaction (PCR) has been shown to be more sensitive than current standard microbiological methods--particularly in patients with prior antibiotic treatment--and therefore, may improve the accuracy of microbiological diagnosis for hospitalized patients with pneumonia. Conventional detection techniques and multiplex PCR for 14 typical bacterial pneumonia-associated pathogens were performed on respiratory samples collected from adult hospitalized patients enrolled in a prospective multi-center study. Patients were enrolled from March until September 2012. A total of 739 fresh, native samples were eligible for analysis, of which 75 were sputa, 421 aspirates, and 234 bronchial lavages. 276 pathogens were detected by microbiology for which a valid PCR result was generated (positive or negative detection result by Curetis prototype system). Among these, 120 were identified by the prototype assay, 50 pathogens were not detected. Overall performance of the prototype for pathogen identification was 70.6% sensitivity (95% confidence interval (CI) lower bound: 63.3%, upper bound: 76.9%) and 95.2% specificity (95% CI lower bound: 94.6%, upper bound: 95.7%). Based on the study results, device cut-off settings were adjusted for future series production. The overall performance with the settings of the CE series production devices was 78.7% sensitivity (95% CI lower bound: 72.1%) and 96.6% specificity (95% CI lower bound: 96.1%). Time to result was 5.2 hours (median) for the prototype test and 43.5 h for standard-of-care. The Pneumonia Application provides a rapid and moderately sensitive assay for the detection of pneumonia-causing pathogens with minimal hands-on time.Deutsches Register Klinischer Studien (DRKS) DRKS00005684.
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- 2014
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21. Direct RNA-based detection and differentiation of CTX-M-type extended-spectrum β-lactamases (ESBL).
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Claudia Stein, Oliwia Makarewicz, Yvonne Pfeifer, Christian Brandt, João Costa Ramos, Mareike Klinger, and Mathias W Pletz
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Medicine ,Science - Abstract
The current global spread of multi-resistant Gram-negatives, particularly extended spectrum β-lactamases expressing bacteria, increases the likelihood of inappropriate empiric treatment of critically ill patients with subsequently increased mortality. From a clinical perspective, fast detection of resistant pathogens would allow a pre-emptive correction of an initially inappropriate treatment. Here we present diagnostic amplification-sequencing approach as proof of principal based on the fast molecular detection and correct discrimination of CTX-M-β-lactamases, the most frequent ESBL family. The workflow consists of the isolation of total mRNA and CTX-M-specific reverse transcription (RT), amplification and pyrosequencing. Due to the high variability of the CTX-M-β-lactamase-genes, degenerated primers for RT, qRT as well as for pyrosequencing, were used and the suitability and discriminatory performance of two conserved positions within the CTX-M genes were analyzed, using one protocol for all isolates and positions, respectively. Using this approach, no information regarding the expected CTX-M variant is needed since all sequences are covered by these degenerated primers. The presented workflow can be conducted within eight hours and has the potential to be expanded to other β-lactamase families.
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- 2013
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22. Evaluation of a polymerase chain reaction assay for pathogen detection in septic patients under routine condition: an observational study.
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Frank Bloos, Svea Sachse, Andreas Kortgen, Mathias W Pletz, Marc Lehmann, Eberhard Straube, Niels C Riedemann, Konrad Reinhart, and Michael Bauer
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Medicine ,Science - Abstract
BACKGROUND: Treatment of septic shock relies on appropriate antimicrobial therapy. Current culture based methods deliver final results after days, which may delay potentially lifesaving adjustments in antimicrobial therapy. This study was undertaken to compare PCR with blood culture results under routine conditions regarding 1. impact on antimicrobial therapy, and 2. time to result, in patients with presumed sepsis. METHODOLOGY/PRINCIPAL FINDINGS: This was an observational study in a 50 beds ICU of a university hospital. In 245 patients with suspected sepsis, 311 concomitant blood cultures and blood for multiplex PCR (VYOO(®)) were obtained. 45 of 311 blood cultures (14.5%) and 94 of 311 PCRs (30.1%) were positive. However, blood culture or microbiological sampling from the presumed site of infection rarely confirmed PCR results and vice versa. Median time to positivity and interquartile range were 24.2 (18.0, 27.5) hours for the PCR and 68 (52.2, 88.5) hours for BC (p
- Published
- 2012
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