Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.878
Filtrar
1.
PLoS One ; 15(6): e0228234, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32589639

RESUMO

A major issue in the surveillance of antimicrobial resistance (AMR) is "de-duplication" or removal of repeated isolates, for which there exist multiple methods. The World Health Organization (WHO) Global Antimicrobial Resistance Surveillance System (GLASS) requires de-duplication by selecting only the first isolate of a given bacterial species per patient per surveillance period per specimen type per age group, gender, and infection origin stratification. However, no study on the comparative application of this method has been reported. The objective of this study was to evaluate differences in data tabulation between the WHO GLASS and the Japan Nosocomial Infections Surveillance (JANIS) system, which counts both patients and isolates after removing repeated isolates of the same bacterial species isolated from a patient within 30 days, regardless of specimen type, but distinguishing isolates with change of antimicrobial resistance phenotype. All bacterial data, consisting of approximately 8 million samples from 1795 Japanese hospitals in 2017 were exported from the JANIS database, and were tabulated using either the de-duplication algorithm of GLASS, or JANIS. We compared the tabulated results of the total number of patients whose blood and urine cultures were taken and of the percentage of resistant isolates of Escherichia coli for each priority antibiotic. The number of patients per specimen type tabulated by the JANIS method was always smaller than that of GLASS. There was a small (< 3%) difference in the percentage of resistance of E. coli for any antibiotic between the two methods in both out- and inpatient settings and blood and urine isolates. The two tabulation methods did not show considerable differences in terms of the tabulated percentages of resistance for E. coli. We further discuss how the use of GLASS tabulations to create a public software and website that could help to facilitate the understanding of and treatment against AMR.


Assuntos
Infecção Hospitalar/epidemiologia , Farmacorresistência Bacteriana , Organização Mundial da Saúde , Adolescente , Adulto , Sangue/microbiologia , Infecção Hospitalar/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Escherichia coli/fisiologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Urina/microbiologia , Adulto Jovem
2.
Anal Chim Acta ; 1113: 18-25, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32340665

RESUMO

Magnetic trapping has been employed in the development of analytical methods owing to its ease and simplicity in handling samples. Nevertheless, the generation of functional probes is usually time consuming. A new and simple affinity method that uses gadolinium ion (Gd3+), a magnetic ion, as affinity probe for magnetic tapping of pathogenic bacteria was demonstrated in the present study. Escherichia coli O157:H7, Staphylococcus aureus, and Acinetobacter baumannii were selected as model bacteria. The model bacteria were magnetically isolated after incubation in Tris buffer (pH 8) containing Gd3+ (0.1 M) under microwave heating (power: 180 W, 90 s × 3). The resultant Gd3+-bacterium conjugates possessed sufficient magnetism, resulting in magnetic aggregations by an external magnet (∼4,000 Gauss). For ease of magnetic isolation, the sample containing Gd3+-bacterium complexes was stirred by a small magnet. After 1 h, the magnet attached with precipitates, i.e., Gd3+-bacterium conjugates, was readily removed using a pair of tweezers. The bacteria in the resultant conjugates were characterized by matrix-assisted laser desorption/ionization mass spectrometry. The limits of detection of the current approach toward E. coli O157:H7, S. aureus, and A. baumannii in complex samples were ∼104-105 cells mL-1.


Assuntos
Acinetobacter baumannii/isolamento & purificação , Técnicas Bacteriológicas/métodos , Escherichia coli O157/isolamento & purificação , Gadolínio/química , Staphylococcus aureus/isolamento & purificação , Acinetobacter baumannii/química , Animais , Sangue/microbiologia , Bovinos , Complexos de Coordenação/química , Difosfatos/química , Escherichia coli O157/química , Limite de Detecção , Fenômenos Magnéticos , Microbiologia do Solo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Staphylococcus aureus/química
3.
Int J Syst Evol Microbiol ; 70(5): 3167-3178, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32302276

RESUMO

The Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella (HACEK) group genus Eikenella contained a single species, Eikenella corrodens, for many years. In November 2019, Eikenella exigua was described after recovery from a brain abscess and blood culture in Norway. Coincidentally, characterization of 22 Gram-negative bacteria resembling Eikenella from 17 Canadian patients had been underway. Seven isolates from five patients were conclusively identifiable as E. corrodens. One (NML 120819) was deemed to represent a species of the genus Eikenella most closely related to E. corrodens. Fourteen isolates had 97.6 to 98.8% similarities to E. corrodens by 16S rRNA gene sequencing, forming three distinct groups by genome analyses. The largest contained ten anaerobic isolates from eight patients recovered from blood, brain, bone and other abscesses; upon re-evaluation, this group was found to be most consistent with E. exigua. A second facultatively anaerobic clade consisted of two ocular isolates from one patient and a sinus isolate from a second patient. The third taxon consisted of a single strictly anaerobic blood culture isolate. The novel taxa, like E. corrodens, were poorly reactive biochemically and difficult to discern from each other phenotypically and chemotaxonomically, including by cellular fatty acids. MALDI-TOF (Bruker) and whole-genome sequencing were used to further characterize isolates. Draft genomes for the strains had similar DNA G+C contents (55.38-58.53 mol%) while sizes varied from 1.82 Mb to 2.54 Mb. We propose here emendations of the genus Eikenella and the species Eikenella exigua, as well as describing Eikenella halliae sp. nov. NML 130454T (=LMG 30894T=NCTC 14180T) and Eikenella longinqua sp. nov. NML 02-A-017T (=LMG 30896T=NCTC 14179T), on the basis of these findings.


Assuntos
Sangue/microbiologia , Eikenella/classificação , Filogenia , Bactérias Anaeróbias/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Hemocultura , Canadá , DNA Bacteriano/genética , Eikenella/isolamento & purificação , Ácidos Graxos/química , Humanos , Noruega , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
4.
J Infect Chemother ; 26(8): 813-817, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32312620

RESUMO

The time to positivity (TTP) of blood culture has significant value for clinicians. However, almost all subjects of previous studies regarding TTP were adults and early infants. Therefore, careful attention is required when referring to previously published data, which might differ according to the age of subjects, as the tendency of infectious focus and pathogens identified from culture vary with age. In this study, we compared the TTP between two pediatric age groups (≤12 months and 13 months to 15 years [>12 months]) at a teaching hospital during a 5-year period. Of the 95 subjects, 41 and 54 were aged ≤12 and > 12 months, among whom true pathogenic bacteria were identified in 12 (29.3%) and 19 (35.2%), respectively. The median TTP for the younger group with pathogenic bacteria was 11.2 (interquartile range, 10.0-11.9) hours, which was significantly shorter than that for the older group (12.6 [interquartile range, 11.9-16.9] hours) (P = 0.01). At 12 h after the initiation of culture, the younger group with pathogenic bacteria had a significantly higher positivity rate (83.3%) than the older group (26.3%) (P < 0.01). The times required for the positivity to exceed 90% were 13.4 and 20.1 h for the younger and older pathogenic groups and 30.4 and 67.8 h for the younger and older contaminant groups, respectively. The range of TTP could be assessed more accurately by considering the effect of age on the infectious background.


Assuntos
Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Hemocultura/métodos , Adolescente , Fatores Etários , Bacteriemia/diagnóstico , Bactérias/isolamento & purificação , Técnicas Bacteriológicas , Sangue/microbiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Fatores de Tempo
5.
J Infect Chemother ; 26(8): 785-789, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32249163

RESUMO

BACKGROUND: To prevent contamination when taking blood culture, there are various effective interventions. Whether there is greater efficacy by using a combination of these interventions has not been widely evaluated. METHODS: Our six-element intervention bundle aimed to prevent contamination of blood culture in our emergency department (ED). Elements were: use of 1% chlorhexidine alcohol, alcohol wiping, hand hygiene, using sterile gloves, using holed sterile cover, and selection of upper extremities as the site of venipuncture. We compared the contamination rate of blood culture between the pre- and the post-intervention periods among all cases with two or more blood cultures taken in our ED. We also evaluated the rate of patients receiving vancomycin among all those transferred to the hospital from the ED. RESULTS: During the pre- and post-intervention periods, 460 and 450 cases were included in analysis, respectively. Contamination of blood culture occurred in 29 pre-intervention cases (6.3%) and five post-interventional cases (1.1%) (relative risk 0.18, 95% confidence interval 0.07 to 0.45; P < 0.001). After bundle implementation, there was significant increase in adherence to using 1% chlorhexidine alcohol, alcohol wiping, hand hygiene, and using holed sterile covers. Among patients admitted to hospital, fewer patients received vancomycin during the post-intervention period than in the pre-intervention period (5.4% vs. 3.2%, P = 0.03). CONCLUSIONS: Our intervention bundle dramatically reduced the contamination rate when drawing blood culture in our ED.


Assuntos
Sangue/microbiologia , Serviço Hospitalar de Emergência , Contaminação de Equipamentos/prevenção & controle , Flebotomia/métodos , Anti-Infecciosos Locais/uso terapêutico , Hemocultura/métodos , Clorexidina/uso terapêutico , Desinfetantes/uso terapêutico , Higiene das Mãos , Humanos
6.
J Med Microbiol ; 69(4): 552-557, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32141812

RESUMO

Introduction. Staphylococcus aureus bacteraemia (SAB) causes significant morbidity and mortality. Standard diagnostic methods require 24-48 h to provide results, during which time management is guideline-based and may be suboptimal.Aim. Evaluate the impact of rapid molecular detection of S. aureus in positive blood culture bottle fluid on patient management.Methodology. Samples were tested prospectively at two clinical centres. Positive blood cultures with Gram-positive cocci in clusters on microscopy were tested with the Xpert MRSA/SA blood culture assay (Cepheid), as well as standard culture-based identification and antimicrobial sensitivity tests. Results were passed to clinical microbiologists in real time and used for patient management.Results. Of 264 blood cultures tested (184 and 80 from each centre), S. aureus was grown from 39 (14.8 %) with one identified as methicillin-resistant S. aureus; all Xpert results agreed with culture results. Median turnaround time from culture flagging positive to result reporting for Xpert was 1.7 h, compared to 25.7 h for species identification by culture. Xpert results allowed early changes to management in 40 (16.8 %) patients, with Xpert positive patients starting specific therapy for SAB and Xpert negative patients stopping or avoiding empiric antimicrobials for SAB.Conclusion. Rapid and accurate detection of S. aureus with the Xpert MRSA/SA BC assay in positive blood culture bottles allowed earlier targeted patient management. Negative Xpert results are suggestive of coagulase negative staphylococci, allowing de-escalation of antimicrobial therapy if clinically appropriate.


Assuntos
Bacteriemia/diagnóstico , Hemocultura/métodos , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus/isolamento & purificação , Bacteriemia/sangue , Bacteriemia/microbiologia , Sangue/microbiologia , Humanos , Estudos Prospectivos , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética
7.
Vet Surg ; 49(5): 989-996, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32166777

RESUMO

OBJECTIVE: To determine the ability of cell salvage washing and leukoreduction filtration to remove bacterial contamination from canine whole blood. STUDY DESIGN: Ex vivo nested cohort study. SAMPLE POPULATION: Commercially purchased fresh canine whole blood (n = 33 units). METHODS: Commercially obtained canine whole blood was inoculated with known concentrations of one of three species of bacteria, Escherichia coli (ATCC 25922), Staphylococcus pseudintermedius (quality control strain; Texas A&M University), or Pseudomonas aeruginosa (ATCC 27853). Negative controls were inoculated with sterile saline. The inoculated blood was processed through a cell salvage system and filtered through a series of two leukocyte reduction filters. Samples were aseptically collected at five points during processing (inoculum, prewash, postwash, post-first filtration, and post-second filtration) for bacterial enumeration. RESULTS: Bacterial concentrations were reduced by 85.2%, 91.5%, and 93.9% for E coli, S pseudintermedius, and P aeruginosa, respectively, after washing (P < .0001), and bacterial concentrations were reduced by 99.9%, 100%, and 100%, respectively, after the first filtration (P < .0001). After the second filtration, none of the three species of bacteria could be isolated (100% reduction). No bacterial growth was obtained from negative controls throughout the study. The type of bacteria (P = .29) did not allow prediction of bacterial reduction. CONCLUSION: Cell salvage washing combined with leukoreduction filtration eliminated bacterial contamination of whole dog blood (P < .0001). CLINICAL SIGNIFICANCE: Cell salvage washing and leukoreduction filtration could be applied to intraoperative autotransfusion in clinical animals, especially those treated for trauma or hemorrhage with concurrent bacterial contamination.


Assuntos
Sangue/microbiologia , Cães/sangue , Procedimentos de Redução de Leucócitos/veterinária , Animais , Transfusão de Sangue Autóloga , Estudos de Coortes , Escherichia coli , Filtração/veterinária , Leucócitos
8.
Int J Syst Evol Microbiol ; 70(3): 2016-2025, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32003711

RESUMO

The taxonomic position of an unknown bacterial strain designated CNM695-12, isolated from the blood of an immunocompromised subject, was investigated via phenotypic, chemotaxonomic, genotypic and genomic analyses. Bacterial cells were determined to be Gram-stain-negative bacilli, aerobic, non-motile and non-spore-forming. The strain showed catalase activity but no oxidase activity. Optimal growth occurred at 37 °C, pH 7 and with 0-1 % NaCl. C16 : 0, summed feature 8 (comprising C18 : 1ω7c /C18:1 ω6c), and C18 : 1ω9c were the most abundant fatty acids, and ubiquinone 8 was the major respiratory quinone. The polar lipids present included phosphatidylglycerol, phosphatidylethanolamine and other aminophospholipids. The 16S rRNA gene sequence showed approximately 93.5 % similarity to those of different species with validly published names within the order Burkholderiales (e.g. Leptothrix mobilis Feox-1T, Aquabacterium commune B8T , Aquabacterium citratiphilum B4T and Schlegelella thermodepolymerans K14T). Phylogenetic analyses based on 16S rRNA gene sequences and concatenated alignments including the sequences for 107 essential proteins, revealed the strain to form a novel lineage close to members of the family Comamonadaceae. The highest average nucleotide identity and average amino acid identity values were obtained with Schlegelella thermodepolymerans K14T (69.6 and 55.7 % respectively). The genome, with a size of 3.35 Mb, had a DNA G+C content of 52.4 mol% and encoded 3056 predicted genes, 3 rRNA, 1 transfer-messengerRNA and 51 tRNA. Strain CNM695-12 thus represents a novel species belonging to a novel genus within the order Burkholderiales, for which the name Saezia sanguinis gen. nov., sp. nov. is proposed. The type strain is CNM695-12T (=DSM 104959T=CECT 9208T).


Assuntos
Betaproteobacteria/classificação , Sangue/microbiologia , Filogenia , Idoso de 80 Anos ou mais , Técnicas de Tipagem Bacteriana , Composição de Bases , Betaproteobacteria/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Humanos , Masculino , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espanha , Ubiquinona/química
9.
J Med Microbiol ; 69(2): 249-255, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32003712

RESUMO

Introduction. Among the causative agents of bloodstream infections (BSIs), methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) are the key causative pathogens. Their rapid detection directly from Gram-positive cocci-positive blood culture specimens will promote timely treatment and help to implement effective infection control measures.Aim. We aim to develop a PCR-dipstick technique for the rapid detection of MRSA and VRE directly from positive blood culture specimens.Methodology. PCR-dipstick is a PCR-based multiplex detection technique where DNA-DNA hybridization is employed, and the results are interpreted with the naked eye. It was designed to target three drug resistance genes: mecA in MRSA and vanA/vanB in VRE from positive blood culture specimens. A total of 120 clinical isolates were used to evaluate the sensitivity and specificity of PCR-dipstick. Then, PCR-dipstick was examined for MRSA and VRE detection directly from positive blood cultures.Results. PCR-dipstick showed 100 % sensitivity and specificity in detecting mecA, vanA and vanB genes directly from bacterial colonies in comparison with multiplex PCR for genomic DNA followed by agarose gel electrophoresis. Further, it could differentially detect multiple resistant genes in pooled bacterial colonies (n=10). Ultimately, PCR-dipstick could detect MRSA and VRE in positive blood cultures in ~3 h.Conclusion. The results of the current study substantiate that PCR-dipstick can be used as an efficient detection system for MRSA and VRE directly from Gram-positive cocci-positive blood cultures. Its affordability and rapidity indicate that PCR-dipstick can be an effective tool for controlling nosocomial pathogens.


Assuntos
Proteínas de Bactérias/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Cocos Gram-Positivos/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Sangue/microbiologia , Hemocultura , Farmacorresistência Bacteriana , Infecções por Bactérias Gram-Positivas/sangue , Infecções por Bactérias Gram-Positivas/diagnóstico , Cocos Gram-Positivos/classificação , Cocos Gram-Positivos/efeitos dos fármacos , Cocos Gram-Positivos/isolamento & purificação , Humanos , Reação em Cadeia da Polimerase Multiplex/instrumentação
10.
PLoS One ; 15(1): e0227605, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929575

RESUMO

KHM-1 was first reported in 1997 in Japan as a novel metallo-ß-lactamase mediated by Citrobacter freundii carrying pKHM-1 plasmid. There have been few reports in the clinical field since then. A blaKHM-1-positive Enterobacter hormaechei subsp. hoffmannii in E. cloacae complex, isolate OIPH-N069 was isolated from an inpatient blood culture in 2016. The isolate was characterized by whole-genome sequencing, comparative analysis of the blaKHM-1 encoding plasmid, antimicrobial susceptibility tests, and bacterial conjugation. OIPH-N069 was classified into ST78 of E. cloacae complex, and was multidrug resistant because of the presence of antimicrobial resistance genes in addition to blaKHM-1 on its chromosome and plasmids. blaKHM-1 was located on 136,816 bp of the IncA/C2 plasmid pN069-1, which could be transferred to different bacterial species. The backbone structure, genetic arrangement of the class 1 integron cassette, and the blaKHM-1 gene located downstream of the IncA/C2 antibiotic resistance island, ARI-A, in pN069-1 and pKHM-1 were identical. Horizontal gene transfer of the blaCTX-M-2-ISEcp1 resistance gene module only occurred with pN069-1. The study findings indicate not only the structural conservation of blaKHM-1 encoding plasmids over time and across species, but also the risk of the spread of blaKHM-1 encoding plasmids to other bacterial species and the accumulation of additional resistance genes.


Assuntos
Enterobacter/genética , Infecções por Enterobacteriaceae/microbiologia , Plasmídeos/genética , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sangue/microbiologia , Hemocultura , Sequência Conservada , Farmacorresistência Bacteriana Múltipla , Enterobacter/metabolismo , Infecções por Enterobacteriaceae/sangue , Infecções por Enterobacteriaceae/tratamento farmacológico , Transferência Genética Horizontal , Humanos , Plasmídeos/metabolismo , Sequenciamento Completo do Genoma , beta-Lactamases/genética , beta-Lactamases/metabolismo
11.
J Infect Chemother ; 26(5): 471-474, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31899078

RESUMO

PURPOSE: This study was conducted to estimate the blood culture volume that should be collected from pediatric patients to improve diagnostic abilities. METHODS: Blood cultures from neonates and children aged up to 18 years were collected and the volume was measured for over a 1-year period. During the intervention period, examiners were instructed to draw 3 mL of blood for culture, if possible. The pre-intervention period was from June 1 to August 31, 2016. The post-intervention period was from September 1, 2016, to May 30, 2017. The rate of positive detections was calculated and compared between pre and post-intervention periods. RESULTS: We collected 1352 samples and measured 1327 bottles. During the pre-intervention period, 340 cases were collected with a median blood volume of 1.64 mL; 9 cases (2.7%) were true-positive. During the intervention period, 1012 cases were ordered with a median blood volume of 2.41 mL; 19 cases (1.9%) were true-positive. After intervention, blood volume was increased significantly (p < 0.01). However, there was no significant difference in the rate of positive detections during the study periods (p = 0.254). CONCLUSIONS: In the pediatric clinical setting in a Japanese municipal hospital, the positive detection rate did not improve even when the collected blood volume was increased. One milliliter of blood volume may be adequate for the pediatric bottle in children.


Assuntos
Bacteriemia/diagnóstico , Hemocultura/métodos , Coleta de Amostras Sanguíneas/métodos , Adolescente , Bacteriemia/microbiologia , Técnicas Bacteriológicas , Sangue/microbiologia , Volume Sanguíneo , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pediatria , Flebotomia , Fatores de Tempo
12.
J Pediatric Infect Dis Soc ; 9(3): 326-333, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-31107955

RESUMO

BACKGROUND: Encephalitis is an inflammatory condition of the brain associated with long-term neurologic sequelae and even death in children. Although viruses are often implicated, an etiology is not identified in the majority of cases. Metagenomics-based next-generation sequencing (mNGS) is a high-throughput sequencing technique that can enhance the detection of novel or low-frequency pathogens. METHODS: Hospitalized immunocompetent children aged 6 months to 18 years with encephalitis of unidentified etiology were eligible for enrollment. Demographic, historical, and clinical information was obtained, and residual blood and cerebrospinal fluid (CSF) samples were subjected to mNGS. Pathogens were identified by querying the sequence data against the NCBI GenBank database. RESULTS: Twenty children were enrolled prospectively between 2013 and 2017. mNGS of CSF identified 7 nonhuman nucleic acid sequences of significant frequency in 6 patients, including that of Mycoplasma bovis, parvovirus B19, Neisseria meningitidis, and Balamuthia mandrillaris. mNGS also detected Cladophialophora species, tobacco mosaic virus, and human bocavirus, which were presumed to be contaminants or nonpathogenic organisms. One patient was found to have positive serology results for California encephalitis virus, but mNGS did not detect it. Patients for whom mNGS identified a diagnosis had a significantly higher CSF white blood cell count, a higher CSF protein concentration, and a lower CSF glucose level than patients for whom mNGS did not identify a diagnosis. CONCLUSION: We describe here the results of a prospective cohort analysis to evaluate mNGS as a diagnostic tool for children with unexplained encephalitis. Although mNGS detected multiple nonpathogenic organisms, it also identified multiple pathogens successfully and was most useful in patients with a CSF abnormality.


Assuntos
Encefalite/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Encefalite Infecciosa/diagnóstico , RNA Viral , Adolescente , Sangue/microbiologia , Encéfalo/diagnóstico por imagem , Líquido Cefalorraquidiano/microbiologia , Criança , Pré-Escolar , Encefalite/diagnóstico , Feminino , Humanos , Lactente , Encefalite Infecciosa/microbiologia , Imagem por Ressonância Magnética , Masculino , Estudos Prospectivos , RNA Viral/genética , RNA Viral/isolamento & purificação
14.
Microbiol Immunol ; 64(2): 113-122, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31750556

RESUMO

Streptococcus dysgalactiae subsp. equisimilis (SDSE) causes severe invasive streptococcal infections, especially in elderly people. Between 2013 and 2018, 88 streptococci were isolated from clinical blood culture in a hospital in Toyama prefecture, Japan. The collection included six Group A SDSE (ASD) strains, which are rarely isolated. Multilocus sequence typing categorized five of the six strains into ST128 and the remaining strain into a new type. Maximum-likelihood phylogenetic analysis revealed that the six ASD strains had highly similar genome sequences. Bayesian analysis indicated that the most recent common ancestor of the strains appeared 39 years ago. The ASD strains possessed carbohydrate synthase genes that are conserved in Streptococcus pyogenes strains, whereas one strain featured a different arrangement of the gene cluster. The carbohydrate synthase genes varied by Lancefield type (A, C, and G).


Assuntos
Infecções Estreptocócicas , Streptococcus/genética , Idoso , Teorema de Bayes , Sangue/microbiologia , Metabolismo dos Carboidratos/genética , DNA Bacteriano , Resistência Microbiana a Medicamentos/genética , Genoma Bacteriano , Humanos , Japão/epidemiologia , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus/classificação , Streptococcus/efeitos dos fármacos , Streptococcus/isolamento & purificação , Fatores de Virulência/genética , Sequenciamento Completo do Genoma
15.
Int J Syst Evol Microbiol ; 70(2): 1145-1151, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31860434

RESUMO

Two isolates of a Gram-negative, non-spore-forming coccobacillus cultured from the blood and cerebrospinal fluid of immunocompromised patients in the United States were described previously. Biochemical and phylogenetic analyses revealed that they belong to a novel species within the Francisella genus. Here we describe a third isolate of this species, recovered from blood of a febrile patient with renal failure, and formally name the Francisella species. Whole genome comparisons indicated the three isolates display greater than 99.9 % average nucleotide identity (ANI) to each other and are most closely related to the tick endosymbiont F. persica, with only 88.6-88.8 % ANI to the type strain of F. persica. Based on biochemical, metabolic and genomic comparisons, we propose that these three isolates should be recognized as Francisella opportunistica sp. nov, with the type strain of the species, PA05-1188T, available through the Deutsche Sammlung von Mikroorganismen und Zellkulturen (DSM 107100) and the American Type Culture Collection (ATCC BAA-2974).


Assuntos
Sangue/microbiologia , Líquido Cefalorraquidiano/microbiologia , Francisella/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Francisella/isolamento & purificação , Genes Bacterianos , Humanos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Estados Unidos
16.
Arch Microbiol ; 202(3): 519-523, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31712863

RESUMO

A rod-shaped microorganism with unknown type of flagellation has been accidentally discovered during phase-contrast microscopy of a sample of contaminated human donor blood. The flagellum consists of three fragments that form a complex locomotor device attached to bacterial body. The device provides bacterial motility by rotating around longitudinal axis of bacterial body and so this type of flagellation has been named "rototrichous." This newly discovered bacterial flagellation should be included in the classification of bacterial flagellations.


Assuntos
Bactérias/citologia , Flagelos/química , Bactérias/química , Infecções Bacterianas/sangue , Infecções Bacterianas/microbiologia , Sangue/microbiologia , Humanos , Microscopia de Contraste de Fase
17.
Vet J ; 254: 105396, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31836164

RESUMO

Despite the increasing availability of feline blood, which is collected and stored for transfusion purposes, few studies have assessed the effect of storage on feline whole blood (WB) units. The purpose of this study was to investigate selected hematologic and biochemical changes during storage of feline WB units and to determine when they occurred. Data from a quality control program for WB units was used in this study. Twelve feline WB units, collected using an open system, were sampled every 7 days from the point of collection to the end of storage at 35 days (D0, D7, D14, D21, D28, and D35). Measurements at each time point were: (1) hematologic parameters; (2) percentage hemolysis; (3) morphologic index scored at 0-3, based on echinocyte transformation of the erythrocytes; and (4) selected biochemical parameters. Aerobic and anaerobic culture was performed at D0 and D35. Results were compared statistically to D0 (statistical significance set at <0.01). Storage did not result in statistically significant changes in measured hematological parameters. There were statistically significant increases in percentage hemolysis and morphologic index, starting from D21 (P=0.000 and P=0.004, respectively). Glucose decreased significantly from D21 (P=0.003); potassium increased significantly from D7 (P=0.001); and sodium increased significantly, starting from D28 (P=0.009). Bacteria were not isolated. Blood in feline WB units collected using an open system underwent some significant storage changes that were time-dependent. As these changes could affect the quality and the utility of stored WB used in feline transfusion medicine, further study is required to determine their clinical importance.


Assuntos
Preservação de Sangue/veterinária , Coleta de Amostras Sanguíneas/veterinária , Gatos/sangue , Animais , Sangue/microbiologia , Glicemia/metabolismo , Forma Celular , Testes Hematológicos/veterinária , Hemólise , Potássio/sangue
18.
Pol J Microbiol ; 68(3): 353-369, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31880881

RESUMO

Listeria monocytogenes is the etiological factor of listeriosis. The main source of these organisms is food, including dairy products. The aim was to determine the multiple correlations between the drug susceptibility, virulence genes (VGs), and biofilm formation on silicone teat cups of milk-borne and human L. monocytogenes strains. The spread of L. monocytogenes via contaminated teat rubbers was assessed. The L. monocytogenes strains recovered from milk (18), human blood (10), and the reference strain ATCC®19111™ were used in the study. Penicillin resistance was the most prevalent resistance in the milk isolates (n=8; 44.4%), whereas among clinical strains erythromycin resistance was predominating - (n=6; 60%). The most frequent VGs among strains isolated from milk were hlyA (100%) and plcB (100%) whereas in strains isolated from blood - hlyA (100%) and prfA (90%). All tested VGs were present in 50% of blood isolates and 11% of milk-borne strains. The strains isolated from milk formed a significantly stronger biofilm. The strains with more numerous virulence genes were resistant to more antibiotics and formed a stronger biofilm. It was shown that contaminated teat cups might contribute to the transmission of L. monocytogenes in the herd. It seems reasonable to monitor the occurrence of L. monocytogenes biofilm in a dairy processing environment.Listeria monocytogenes is the etiological factor of listeriosis. The main source of these organisms is food, including dairy products. The aim was to determine the multiple correlations between the drug susceptibility, virulence genes (VGs), and biofilm formation on silicone teat cups of milk-borne and human L. monocytogenes strains. The spread of L. monocytogenes via contaminated teat rubbers was assessed. The L. monocytogenes strains recovered from milk (18), human blood (10), and the reference strain ATCC®19111™ were used in the study. Penicillin resistance was the most prevalent resistance in the milk isolates (n=8; 44.4%), whereas among clinical strains erythromycin resistance was predominating ­ (n=6; 60%). The most frequent VGs among strains isolated from milk were hlyA (100%) and plcB (100%) whereas in strains isolated from blood ­ hlyA (100%) and prfA (90%). All tested VGs were present in 50% of blood isolates and 11% of milk-borne strains. The strains isolated from milk formed a significantly stronger biofilm. The strains with more numerous virulence genes were resistant to more antibiotics and formed a stronger biofilm. It was shown that contaminated teat cups might contribute to the transmission of L. monocytogenes in the herd. It seems reasonable to monitor the occurrence of L. monocytogenes biofilm in a dairy processing environment.


Assuntos
Sangue/microbiologia , Listeria monocytogenes/isolamento & purificação , Listeriose/microbiologia , Leite/microbiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , Bovinos , Humanos , Listeria monocytogenes/classificação , Listeria monocytogenes/genética , Listeria monocytogenes/fisiologia , Listeriose/transmissão , Filogenia , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
19.
Niger J Clin Pract ; 22(12): 1693-1697, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31793476

RESUMO

Objectives: This study aims to measure the level of knowledge of the nurses who collect blood cultures at our hospital, and after providing the necessary training, evaluate the distribution of microbial growth and rate of contamination in blood cultures that are referred to our laboratory during a 1-year term. Methods and Materials: A survey was conducted to assess the level of knowledge regarding blood culture acquisition with the participation of 99 nurses at our hospital in October 2017. Blood cultures sent to our laboratory during 2017 May-October were retrospectively evaluated in terms of their results, contamination rates, and number of bottles. Taking survey results into account, monthly trainings were provided to the nurses for 6 months starting from October 2017, and blood culture results and error rates were investigated prospectively. Results: It was determined from the survey results that the level of knowledge regarding the need to wipe the rubber septum of the blood culture bottle with alcohol prior to adding the blood sample (23.2%) and definition of a blood culture set (25.3%) were quite low. It was found that while the contamination rate prior to training was 6.4%, it fell to 3.7% after training, and although the rate of single-bottle cultures was 6.3% before training, it decreased by 2.0%. Conclusions: Standardizing blood culture acquisition with the provided training will produce maximal benefit for every laboratory in terms of cost and workload.


Assuntos
Hemocultura/normas , Coleta de Amostras Sanguíneas/normas , Sangue/microbiologia , Contaminação de Equipamentos/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Enfermeiras e Enfermeiros/psicologia , Adulto , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Estudos Retrospectivos , Inquéritos e Questionários
20.
Biomed Microdevices ; 21(4): 95, 2019 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-31707575

RESUMO

Enteric fever is one of the leading causes of infection and subsequent fatality (greater than 1.8 million) (WHO 2018), especially in the developing countries due to contaminated water and food inter twinned with unhygienic practices. Clinical gold standard technique of culture-based method followed by biochemical tests demand 72+ hours for diagnosis while newly developed techniques (like PCR, RT-PCR, DNA microarray etc.) suffer from high limit of detection or involve high-cost infrastructure or both. In this work, a quick and highly specific method, SMOL was established for simultaneous detection of Salmonella paratyphi A and Salmonella typhi in clinical blood samples. SMOL consists of (i) pre-concentration of S. typhi and S. paratyphi A cells using magnetic nanoparticles followed by (ii) cell lysis and DNA extraction (iii) amplification of select nucleic acids by LAMP technique and (iv) detection of amplified nucleic acids using an affordable portable device (costs less than $70). To identify the viability of target cells at lower concentrations, the samples were processed at two different time periods of t = 0 and t = 4 h. Primers specific for the SPA2539 gene in S. paratyphi A and STY2879 gene in S. typhi were used for LAMP. Within 6 h SMOL was able to detect positive and negative samples from 55 human clinical blood culture samples and detect the viability of the cells. The results were concordant with culture and biochemical tests as well as by qPCR. Statistical power analysis yielded 100%. SMOL results were concordant with culture and biochemical tests as well as by qPCR. The sensitive and affordable system SMOL will be effective for poor resource settings.


Assuntos
Sangue/microbiologia , Custos e Análise de Custo , Limite de Detecção , Salmonella paratyphi A/isolamento & purificação , Salmonella typhi/isolamento & purificação , Testes Sorológicos/economia , Testes Sorológicos/instrumentação , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Humanos , Técnicas de Amplificação de Ácido Nucleico , Salmonella paratyphi A/genética , Salmonella typhi/genética , Fatores de Tempo , Febre Tifoide/microbiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA