RESUMEN
BACKGROUND: Linezolid-resistant Enterococcus faecium (LRE) is a global priority pathogen. Thirteen LRE were reported from clinical specimens between November 2021 and April 2023 at two laboratories in Karachi, Pakistan. We aimed to investigate the strain types and genes associated with linezolid resistance among these isolates. Whole genome sequencing (WGS) was performed and analyzed by multilocus sequence typing (MLST). The presence of linezolid resistance genes was identified using ResFinder v4.1.11 and the LRE-finder tool. RESULTS: Twelve isolates belonged to clonal complex 17 (CC17); ST80 (n = 10), ST612 (n = 1) and ST1380 (n = 1). Six isolates showed the presence of optrA gene and G2576T mutations in the 23S rRNA gene, while six showed poxtA and cfr(D) genes. One isolate showed the combination of optrA, cfr(D) and poxtA genes. CONCLUSION: Our findings show the circulation of CC17 sequence types with a known outbreak potential and we identified molecular mechanisms of resistance that were not previously reported from Pakistan.
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Antibacterianos , Farmacorresistencia Bacteriana , Enterococcus faecium , Infecciones por Bacterias Grampositivas , Linezolid , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Secuenciación Completa del Genoma , Enterococcus faecium/genética , Enterococcus faecium/efectos de los fármacos , Enterococcus faecium/aislamiento & purificación , Enterococcus faecium/clasificación , Pakistán , Linezolid/farmacología , Humanos , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , ARN Ribosómico 23S/genética , Femenino , Masculino , Genoma Bacteriano/genética , Genómica , Adulto , Proteínas Bacterianas/genética , Persona de Mediana Edad , MutaciónRESUMEN
The cell wall is an indispensable element of bacterial cells and a long-known target of many antibiotics. Penicillin, the first discovered beta-lactam antibiotic inhibiting the synthesis of cell walls, was successfully used to cure many bacterial infections. Unfortunately, pathogens eventually developed resistance to it. This started an arms race, and while novel beta-lactams, either natural or (semi)synthetic, were discovered, soon upon their application, bacteria were developing resistance. Currently, we are facing the threat of losing the race since more and more multidrug-resistant (MDR) pathogens are emerging. Therefore, there is an urgent need for developing novel approaches to combat MDR bacteria. The cell wall is a reasonable candidate for a target as it differentiates not only bacterial and human cells but also has a specific composition unique to various groups of bacteria. This ensures the safety and specificity of novel antibacterial agents that target this structure. Due to the shortage of low-molecular-weight candidates for novel antibiotics, attention was focused on peptides and proteins that possess antibacterial activity. Here, we describe proteinaceous agents of various origins that target bacterial cell wall, including bacteriocins and phage and bacterial lysins, as alternatives to classic antibiotic candidates for antimicrobial drugs. Moreover, advancements in protein chemistry and engineering currently allow for the production of stable, specific, and effective drugs. Finally, we introduce the concept of selective targeting of dangerous pathogens, exemplified by staphylococci, by agents specifically disrupting their cell walls.
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Antibacterianos , Pared Celular , Bacterias Grampositivas , Pared Celular/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Bacterias Grampositivas/efectos de los fármacos , Humanos , Bacteriocinas/farmacología , Bacteriocinas/química , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología , BacteriófagosRESUMEN
Amongst all Enterococcus spp., E. faecalis and E. faecium are most known notorious pathogen and their biofilm formation has been associated with endocarditis, oral, urinary tract, and wound infections. Biofilm formation involves a pattern of initial adhesion, microcolony formation, and mature biofilms. The initial adhesion and microcolony formation involve numerous surface adhesins e.g. pili Ebp and polysaccharide Epa. The mature biofilms are maintained by eDNA, It's worth noting that phage-mediated dispersal plays a prominent role. Further, the involvement of peptide pheromones in regulating biofilm maintenance sets it apart from other pathogens and facilitating the horizontal transfer of resistance genes. The role of fsr based regulation by regulating gelE expression is also discussed. Thus, we provide a concise overview of the significant determinants at each stage of Enterococcus spp. biofilm formation. These elements could serve as promising targets for antibiofilm strategies.
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Biopelículas , Enterococcus , Infecciones por Bacterias Grampositivas , Enterococcus/genética , Enterococcus/metabolismo , Regulación Bacteriana de la Expresión Génica , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/fisiopatología , Adhesión Bacteriana/genética , Adhesinas Bacterianas/genética , Adhesinas Bacterianas/metabolismo , Polisacáridos Bacterianos/metabolismo , Transferencia de Gen HorizontalRESUMEN
Vancomycin-resistant Enterococcus faecium (VRE) has been detected in Türkiye. Only limited information is available on its dissemination in the central regions of the country. This study describes the first epidemiological characterization of VRE clinical isolates detected in patients in a hospital in the province of Aksaray. In this one-year study conducted between 2021 and 2022, stool samples from intensive care unit patients were screened for VRE using the phenotypic E-test method, and the antibiotic sensitivity test was analyzed by using the VITEK® 2 system. A molecular assay for confirmation of species level was carried out by 16S rRNA gene-based sequencing and testing for antibiotic resistance (vanA or vanB) and virulence factor-encoding genes (esp, asa1, and hyl). Further, genotypic characterization was determined by macro-restriction fragment pattern analysis (MRFPA) of genomic DNA digested with SmaI restriction enzyme. Of the total 350 Enterococcus positive patients from different hospital intensive care units, 22 (6.3%) were positive for VRE using the phenotypic E-test method. All isolates showed resistance to ampicillin, ciprofloxacin, vancomycin, and teicoplanin and positive amplification for the vanA gene. However, none of the isolates was positive for the vanB gene. The most prevalent virulence gene was esp. The results indicate that the isolates are persistent in the hospital environment and subsequently transmitted to hospitalized patients, thus representing challenges to an outbreak and infection control. These study results would also help formulate more effective strategies to reduce the transmission and propagation of VRE contamination in various hospital settings.
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Antibacterianos , Proteínas Bacterianas , Enterococcus faecium , Genotipo , Infecciones por Bacterias Grampositivas , Unidades de Cuidados Intensivos , Pruebas de Sensibilidad Microbiana , Enterococos Resistentes a la Vancomicina , Humanos , Enterococcus faecium/genética , Enterococcus faecium/efectos de los fármacos , Enterococcus faecium/aislamiento & purificación , Enterococos Resistentes a la Vancomicina/genética , Enterococos Resistentes a la Vancomicina/aislamiento & purificación , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Factores de Virulencia/genética , Vancomicina/farmacología , Heces/microbiología , ARN Ribosómico 16S/genética , Fenotipo , Masculino , Femenino , Resistencia a la Vancomicina/genética , Persona de Mediana EdadRESUMEN
The aim of this work was to provide a theoretical and scientific basis for the treatment, prevention, and control of clinical drug-resistant bacterial infections by studying the molecular epidemiology and horizontal transfer mechanism of optrA-carrying linezolid-resistant Enterococcus faecalis strains (LREfs) that were clinically isolated in a tertiary hospital in Kunming, China. Non-repetitive LREfs retained in a tertiary A hospital in Kunming, China. The strains were identified by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The transferability and horizontal transfer mechanism of optrA gene were analyzed using polymerase chain reaction (PCR), whole-genome sequencing (WGS), and conjugation experiments. A total of 39 LREfs strains were collected, and all of them were multi-drug resistant. There were 30 LREfs strains (76.9%) carrying the optrA gene, The cfr, poxtA genes and mutations in the 23S rRNA gene were not detected. The conjugation experiments showed that only three of 10 randomly selected optrA-carrying LREfs were successfully conjugated with JH2-2. Further analysis of one successfully conjugated strain revealed that the optrA gene, located in the donor bacterium, formed the IS1216E-erm(A)-optrA-fexA-IS1216E transferable fragment under the mediation of the mobile genetic element (MGE) IS1216E, which was then transferred to the recipient bacterium via horizontal plasmid transfer. Carrying the optrA gene is the primary resistance mechanism of LREfs strains. The optrA gene could carry the erm(A) and fexA genes to co-transfer among E. faecalis. MGEs such as insertion sequence IS1216E play an important role in the horizontal transfer of the optrA gene.
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Antibacterianos , Enterococcus faecalis , Transferencia de Gen Horizontal , Infecciones por Bacterias Grampositivas , Linezolid , Enterococcus faecalis/genética , Enterococcus faecalis/efectos de los fármacos , Linezolid/farmacología , Antibacterianos/farmacología , Humanos , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , China/epidemiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Epidemiología Molecular , Farmacorresistencia Bacteriana/genética , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Bacteriana Múltiple/genética , Secuenciación Completa del Genoma , Conjugación GenéticaRESUMEN
BACKGROUND: Glycopeptides for ampicillin-susceptible Enterococcus faecalis/faecium bacteremia are readily prescribed depending on the severity of the condition. However, there is limited data on the outcomes of glycopeptide use compared to ampicillin-containing regimens for ampicillin-susceptible E. faecalis/faecium bacteremia. From an antibiotic stewardship perspective, it is important to determine whether the use of glycopeptides is associated with improved clinical outcomes in patients with ampicillin-susceptible E. faecalis/faecium bacteremia. METHODS: This retrospective cohort study was conducted at a university-affiliated hospital between January 2010 and September 2019. We collected data from patients with positive blood cultures for Enterococcus species isolates. The clinical data of patients who received ampicillin-containing regimens or glycopeptides as definitive therapy for ampicillin-susceptible E. faecalis/faecium bacteremia were reviewed. Multivariate logistic regression analysis was performed to identify risk factors for 28-day mortality. RESULTS: Ampicillin-susceptible E. faecalis/faecium accounted for 41.2% (557/1,353) of enterococcal bacteremia cases during the study period. A total of 127 patients who received ampicillin-containing regimens (N = 56) or glycopeptides (N = 71) as definitive therapy were included in the analysis. The 28-day mortality rate was higher in patients treated with glycopeptides (19.7%) than in those treated with ampicillin-containing regimens (3.6%) (p = 0.006). However, in the multivariate model, antibiotic choice was not an independent predictor of 28-day mortality (adjusted OR, 3.7; 95% CI, 0.6-23.6). CONCLUSIONS: Glycopeptide use was not associated with improved mortality in patients with ampicillin-susceptible E. faecalis/faecium bacteremia. This study provides insights to reduce the inappropriate use of glycopeptides in ampicillin-susceptible E. faecalis/faecium bacteremia treatment and promote antimicrobial stewardship.
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Ampicilina , Antibacterianos , Bacteriemia , Enterococcus faecalis , Glicopéptidos , Infecciones por Bacterias Grampositivas , Sulbactam , Humanos , Estudios Retrospectivos , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Bacteriemia/mortalidad , Ampicilina/uso terapéutico , Ampicilina/farmacología , Masculino , Femenino , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Enterococcus faecalis/efectos de los fármacos , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/mortalidad , Anciano , Persona de Mediana Edad , Glicopéptidos/uso terapéutico , Glicopéptidos/farmacología , Sulbactam/uso terapéutico , Sulbactam/farmacología , Resultado del Tratamiento , Pruebas de Sensibilidad Microbiana , Anciano de 80 o más AñosRESUMEN
BACKGROUND: Pulmonary alveolar proteinosis (PAP) is a special clinical presentation mostly associated with autoimmune disorders. Here we report a rare case of PAP secondary to infection of Bacillus megaterium. CASE PRESENTATION: A 58-year-old woman presented with intermittent cough and dyspnea for half a year. Chest CT scan showed "crazy paving" pattern. B. megaterium was identified by percutaneous CT-guided needle biopsy. She continuously received antimicrobial treatment since the diagnosis and follow-up examination suggested great improvement. CONCLUSIONS: To our knowledge, this is the first case of B. megaterium infection presented with PAP pattern in healthy individuals. Attention should be paid on the secondary causes including rare pathogen infection when patients presented with PAP syndrome.
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Bacillus megaterium , Proteinosis Alveolar Pulmonar , Tomografía Computarizada por Rayos X , Humanos , Femenino , Persona de Mediana Edad , Proteinosis Alveolar Pulmonar/diagnóstico , Proteinosis Alveolar Pulmonar/diagnóstico por imagen , Proteinosis Alveolar Pulmonar/patología , Bacillus megaterium/aislamiento & purificación , Infecciones por Bacterias Grampositivas/diagnóstico , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Antibacterianos/uso terapéuticoRESUMEN
BACKGROUND: Due to the increasing emergence of antibiotic resistance in Enterococcus faecalis (E. faecalis), it indicated as potentially opportunistic pathogen causing various healthcare-associated and life-threatening diseases around the world. OBJECTIVE: The aim of this meta-analysis was to evaluate the weighted pooled resistance rates in clinical E. faecalis isolates based on over time, areas, antimicrobial susceptibility testing (AST), and infection source. METHODS: We searched the studies in PubMed, Scopus, and Web of Science (November 30, 2022). All statistical analyses were carried out using the statistical package R. RESULTS: The analysis encompassed a total of 74 studies conducted in 28 countries. According to the meta-regression, the chloramphenicol, fosfomycin, imipenem, linezolid, minocycline, norfloxacin, quinupristin-dalfopristin, and tetracycline resistance rate increased over time. Analysis revealed statistically significant differences in antibiotic resistance rates for ampicillin, chloramphenicol, erythromycin, gentamicin, penicillin, rifampicin, teicoplanin, tetracycline, and vancomycin across various countries. CONCLUSIONS: Globally, the prevalence of drug resistant E. faecalis strains are on the increase over time. Daptomycin and tigecycline can be an effective agent for the treatment of clinical E. faecalis infections. Considering the low prevalence of antibiotic resistance in continents of Europe and Australia, it is suggested to take advantage of their preventive strategies in order to obtain efficient results in other places with high prevalence of resistance.
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Antibacterianos , Enterococcus faecalis , Infecciones por Bacterias Grampositivas , Pruebas de Sensibilidad Microbiana , Enterococcus faecalis/efectos de los fármacos , Humanos , Antibacterianos/farmacología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/epidemiología , Farmacorresistencia Bacteriana , Salud Global , Farmacorresistencia Bacteriana MúltipleRESUMEN
This study presents the empirical findings of an in-depth genomic analysis of Enterococcus faecalis and Enterococcus lactis isolates from South Africa. It offers valuable insights into their genetic characteristics and their significant implications for public health. The study uncovers nuanced variations in the gene content of these isolates, despite their similar GC contents, providing a comprehensive view of the evolutionary diversity within the species. Genomic islands are identified, particularly in E. faecalis, emphasizing its propensity for horizontal gene transfer and genetic diversity, especially in terms of antibiotic resistance genes. Pangenome analysis reveals the existence of a core genome, accounting for a modest proportion of the total genes, with 2157 core genes, 1164 shell genes, and 4638 cloud genes out of 7959 genes in 52 South African E. faecalis genomes (2 from this study, 49 south Africa genomes downloaded from NCBI, and E. faecalis reference genome). Detecting large-scale genomic rearrangements, including chromosomal inversions, underscores the dynamic nature of bacterial genomes and their role in generating genetic diversity. The study uncovers an array of antibiotic resistance genes, with trimethoprim, tetracycline, glycopeptide, and multidrug resistance genes prevalent, raising concerns about the effectiveness of antibiotic treatment. Virulence gene profiling unveils a diverse repertoire of factors contributing to pathogenicity, encompassing adhesion, biofilm formation, stress resistance, and tissue damage. These empirical findings provide indispensable insights into these bacteria's genomic dynamics, antibiotic resistance mechanisms, and virulence potential, underlining the pressing need to address antibiotic resistance and implement robust control measures.
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Antibacterianos , Enterococcus faecalis , Variación Genética , Genoma Bacteriano , Factores de Virulencia , Sudáfrica , Enterococcus faecalis/genética , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/patogenicidad , Enterococcus faecalis/aislamiento & purificación , Virulencia/genética , Antibacterianos/farmacología , Factores de Virulencia/genética , Humanos , Farmacorresistencia Bacteriana/genética , Islas Genómicas/genética , Infecciones por Bacterias Grampositivas/microbiología , Enterococcus/genética , Enterococcus/efectos de los fármacos , Enterococcus/patogenicidad , Enterococcus/aislamiento & purificación , Enterococcus/clasificación , Filogenia , Transferencia de Gen Horizontal , Genómica , Pruebas de Sensibilidad MicrobianaRESUMEN
PURPOSES: Enterococcal BSI is associated with significant morbidity and mortality, with fatality rates of approximately 20-30%. There are microbiological and clinical differences between E. faecalis and E. faecium infections. The aim of this study was to investigate differences in predisposing factors for E. faecalis and E. faecium BSI and to explore prognostic factors. METHODS: This study was a post-hoc analysis of PROBAC, a Spanish prospective, multicenter, cohort in 2016-2017. Patients with E. faecalis or E. faecium BSI were eligible. Independent predictors for BSI development in polymicrobial and monomicrobial BSI and in-hospital mortality in the monomicrobial group were identified by logistic regression. RESULTS: A total of 431 patients were included. Independent factors associated with E. faecium BSI were previous use of penicillins (aOR 1.99 (95% CI 1.20-3.32)) or carbapenems (2.35 (1.12-4.93)), hospital-acquired BSI (2.58 (1.61-4.12)), and biliary tract source (3.36 (1.84-6.13)), while congestive heart failure (0.51 (0.27-0.97)), cerebrovascular disease (0.45 (0.21-0.98)), and urinary tract source (0.49 (0.26-0.92)) were associated with E. faecalis BSI. Independent prognostic factors for in-hospital mortality in E. faecalis BSI were Charlson Comorbidity Index (1.27 (1.08-1.51)), SOFA score (1.47 (1.24-1.73)), age (1.06 (1.02-1.10)), and urinary/biliary source (0.29 (0.09-0.90)). For E. faecium BSI, only SOFA score (1.34 (1.14-1.58) was associated with in-hospital mortality. CONCLUSIONS: The factors associated with E. faecium and E. faecalis BSI are different. These variables may be helpful in the suspicion of one or other species for empiric therapeutic decisions and provide valuable information on prognosis.
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Bacteriemia , Enterococcus faecalis , Enterococcus faecium , Infecciones por Bacterias Grampositivas , Humanos , Enterococcus faecalis/aislamiento & purificación , Masculino , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/mortalidad , Infecciones por Bacterias Grampositivas/epidemiología , Femenino , Estudios Prospectivos , Enterococcus faecium/aislamiento & purificación , Enterococcus faecium/efectos de los fármacos , Anciano , Persona de Mediana Edad , Bacteriemia/microbiología , Bacteriemia/epidemiología , Bacteriemia/mortalidad , Factores de Riesgo , Anciano de 80 o más Años , Mortalidad Hospitalaria , Antibacterianos/uso terapéutico , Pronóstico , España/epidemiología , Infección Hospitalaria/microbiología , Infección Hospitalaria/epidemiología , Infección Hospitalaria/mortalidadRESUMEN
Vancomycin-resistant enterococcus (VRE) is a major nosocomial pathogen that exhibits enhanced infectivity due to its robust virulence and biofilm-forming capabilities. In this study, 6-methoxyldihydrochelerythrine chloride (6-MDC) inhibited the growth of exponential-phase VRE and restored VRE's sensitivity to vancomycin. 6-MDC predominantly suppressed the de novo biosynthetic pathway of pyrimidine and purine in VRE by the RNA-Seq analysis, resulting in obstructed DNA synthesis, which subsequently weakened bacterial virulence and impeded intracellular survival. Furthermore, 6-MDC inhibited biofilm formation, eradicated established biofilms, reduced virulence, and enhanced the host immune response to prevent intracellular survival and replication of VRE. Finally, 6-MDC reduced the VRE load in peritoneal fluid and cells significantly in a murine peritoneal infection model. This paper provides insight into the potential antimicrobial target of benzophenanthridine alkaloids for the first time.
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Antibacterianos , Benzofenantridinas , Biopelículas , Pruebas de Sensibilidad Microbiana , Enterococos Resistentes a la Vancomicina , Animales , Ratones , Antibacterianos/farmacología , Antibacterianos/química , Benzofenantridinas/farmacología , Benzofenantridinas/química , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Biopelículas/efectos de los fármacos , Virulencia/efectos de los fármacos , Vancomicina/farmacología , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología , Humanos , FemeninoRESUMEN
BACKGROUND: Postoperative infection after the Latarjet procedure, ranging from 1% to 6%, can compromise the functional outcome of young athletes. Cutibacterium acnes is a main pathogen as a consequence of an intraoperative contamination. PURPOSE: To evaluate intraoperative contamination with C. acnes and the effectiveness of the local application of vancomycin during the Latarjet procedure. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: This was a single-center study including 75 patients (mean age, 26 years; range, 15-55 years) operated on for anterior shoulder instability with the primary open Latarjet procedure; they underwent the same protocol of skin preparation and preoperative prophylactic antibiotics. Three groups of 25 patients were created and divided sequentially, without the results of each group being known before the end of the study: group A (5 mg/mL of vancomycin), group B (20 mg/mL of vancomycin), and group C (control group with no vancomycin). Swab samples of the coracoid were taken before sectioning the coracoid process (time 1) and after its preparation (time 2). The coracoid was then wrapped in gauze impregnated with different concentrations of vancomycin, except for group C. A final sample (time 3) was taken before screwing the bone block onto the glenoid. All samples were cultured for 21 days, and patients underwent clinical and radiological follow-up for 6 months. RESULTS: The C. acnes contamination rates at times 1, 2, and 3 were 25%, 44%, and 45%, respectively, without significant difference. There was no significant difference between groups A and B with respect to the number of positive cultures at each time point. Of 9 positive cultures at time 1, all were still positive at time 3 in group A, whereas 3 of 5 were negative in group B (P = .027). The rate of C. acnes at time 3 in the control group was higher than that in the 2 other groups (68% vs 44% for group A and 20% for group B; P = .003). Body mass index was the only prognostic factor for a C. acnes-positive culture (26.05 ± 3.39 vs 23.34 ± 2.33; P = .018). No clinical infection was reported at the 6-month postoperative follow-up. CONCLUSION: The rate of C. acnes contamination ranged from 25% to 68% during the open Latarjet procedure in young athletes. Vancomycin reduced the bacterial contamination when it was used at high concentrations in a gauze wrap on the coracoid. The type of C. acnes detected and its clinical implications remain to be studied.
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Antibacterianos , Infección de la Herida Quirúrgica , Vancomicina , Humanos , Vancomicina/administración & dosificación , Vancomicina/uso terapéutico , Adolescente , Masculino , Adulto Joven , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , Adulto , Femenino , Persona de Mediana Edad , Infección de la Herida Quirúrgica/prevención & control , Infección de la Herida Quirúrgica/microbiología , Profilaxis Antibiótica/métodos , Propionibacterium acnes , Infecciones por Bacterias Grampositivas/prevención & control , Infecciones por Bacterias Grampositivas/microbiología , Estudios de CohortesRESUMEN
AIMS: In Tunisia, limited research has focused on characterizing clinical vancomycin-resistant Enterococcus faecium (VREfm). This study aimed to bridge this knowledge gap by molecular characterization of antimicrobial resistance, determining the genetic elements mediating vancomycin-resistance, and whole-genome sequencing of one representative VREfm isolate. METHODS AND RESULTS: Over 6 years (2011-2016), a total of eighty VREfm isolates responsible for infection or colonization were identified from hospitalized patients, with the incidence rate increasing from 2% in 2011 to 27% in 2016. All of these strains harbored the vanA gene. The screening for antimicrobial resistance genes revealed the predominance of ermB, tetM, and aac(6')-Ie-aph(2'')-Ia genes and 81.2% of strains harbored the Tn1545. Pulsed-field gel electrophoresis identified seven clusters, with two major clusters (belonging to ST117 and ST80) persisting throughout the study period. Seven Tn1546 types were detected, with type VI (truncated transposon) being the most prevalent (57.5%). Whole-genome sequencing revealed a 3 028 373 bp chromosome and five plasmids. Mobile genetic elements and a type I CRISPR-cas locus were identified. Notably, the vanA gene was carried by the classic Tn1546 transposon with ISL3 insertion on a rep17pRUM plasmid. CONCLUSION: A concerning trend in the prevalence of VREfm essentially attributed to CC17 persistence and to horizontal transfer of multiple genetic variants of truncated vanA-Tn1546.
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Elementos Transponibles de ADN , Enterococcus faecium , Variación Genética , Infecciones por Bacterias Grampositivas , Neutropenia , Enterococos Resistentes a la Vancomicina , Secuenciación Completa del Genoma , Humanos , Enterococcus faecium/genética , Enterococcus faecium/aislamiento & purificación , Enterococcus faecium/efectos de los fármacos , Túnez , Enterococos Resistentes a la Vancomicina/genética , Enterococos Resistentes a la Vancomicina/aislamiento & purificación , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Elementos Transponibles de ADN/genética , Neutropenia/microbiología , Neutropenia/complicaciones , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Pruebas de Sensibilidad Microbiana , Electroforesis en Gel de Campo Pulsado , Resistencia a la Vancomicina/genética , Vancomicina/farmacologíaRESUMEN
Early detection of disseminating vancomycin-resistant Enterococcus faecium (VREfm) in ICU wards is crucial for outbreak identification and the implementation of prompt infection control measures. Genotypic methods like pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS) are costly and time-consuming, hindering rapid response due to batch dependency. Fourier-transform infrared spectroscopy (FT-IR) offers the potential for real-time outbreak detection and reliable strain typing. We utilized FT-IR to identify clonal VREfm dissemination and compared its performance to PFGE and WGS. Between February through October 2023, an unusually high number of VREfm were recovered at a tertiary hospital in Barcelona. Isolates were examined for antimicrobial susceptibility, carriage of vanA/vanB genes and clonality was also studied using FT-IR, PFGE, and WGS. Routine FT-IR inspections revealed recurring VREfm clustering during the outbreak's initial weeks. In total, 104 isolates were recovered from 75 patients and from multiple wards. However, only one isolate was recovered from an environmental sample, suggesting the absence of environmental reservoirs. An ST80 vancomycin-resistant (vanA) E. faecium strain was the main strain responsible for the outbreak, although a few additional VREfm strains were also identified, all belonging to CC17. PFGE and cgMLST (WGS) yielded identical clustering results to FT-IR, and WGS confirmed vanA/vanB gene carriage in all VREfm isolates. Infection control measures led to a rapid decline in VREfm isolates, with no isolates detected in November. FT-IR spectroscopy offers rapid turnaround times, sensitivity, and reproducibility, comparable to standard typing methods. It proved as an effective tool for monitoring VREfm dissemination and early outbreak detection.
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Infección Hospitalaria , Electroforesis en Gel de Campo Pulsado , Enterococcus faecium , Infecciones por Bacterias Grampositivas , Enterococos Resistentes a la Vancomicina , Secuenciación Completa del Genoma , Humanos , Enterococcus faecium/genética , Enterococcus faecium/efectos de los fármacos , Enterococcus faecium/aislamiento & purificación , Enterococcus faecium/clasificación , Enterococos Resistentes a la Vancomicina/genética , Enterococos Resistentes a la Vancomicina/aislamiento & purificación , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Enterococos Resistentes a la Vancomicina/clasificación , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Infección Hospitalaria/microbiología , Infección Hospitalaria/epidemiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Secuenciación Completa del Genoma/métodos , Brotes de Enfermedades , Proteínas Bacterianas/genética , Pruebas de Sensibilidad Microbiana , España/epidemiología , Ligasas de Carbono-Oxígeno/genética , Antibacterianos/farmacologíaRESUMEN
Enterococcus faecalis (E. faecalis) is a growing cause of nosocomial and antibiotic-resistant infections. Treating drug-resistant E. faecalis requires novel approaches. The use of bacteriophages (phages) against multidrug-resistant (MDR) bacteria has recently garnered global attention. Biofilms play a vital role in E. faecalis pathogenesis as they enhance antibiotic resistance. Phages eliminate biofilms by producing lytic enzymes, including depolymerases. In this study, Enterococcus phage vB_Efs8_KEN04, isolated from a sewage treatment plant in Nairobi, Kenya, was tested against clinical strains of MDR E. faecalis. This phage had a broad host range against 100% (26/26) of MDR E. faecalis clinical isolates and cross-species activity against Enterococcus faecium. It was able to withstand acidic and alkaline conditions, from pH 3 to 11, as well as temperatures between -80 °C and 37 °C. It could inhibit and disrupt the biofilms of MDR E. faecalis. Its linear double-stranded DNA genome of 142,402 bp contains 238 coding sequences with a G + C content and coding gene density of 36.01% and 91.46%, respectively. Genomic analyses showed that phage vB_Efs8_KEN04 belongs to the genus Kochikohdavirus in the family Herelleviridae. It lacked antimicrobial resistance, virulence, and lysogeny genes, and its stability, broad host range, and cross-species lysis indicate strong potential for the treatment of Enterococcus infections.
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Bacteriófagos , Biopelículas , Farmacorresistencia Bacteriana Múltiple , Enterococcus faecalis , Genoma Viral , Especificidad del Huésped , Biopelículas/crecimiento & desarrollo , Biopelículas/efectos de los fármacos , Enterococcus faecalis/virología , Enterococcus faecalis/efectos de los fármacos , Kenia , Bacteriófagos/fisiología , Bacteriófagos/genética , Bacteriófagos/aislamiento & purificación , Bacteriófagos/clasificación , Humanos , Antibacterianos/farmacología , Infecciones por Bacterias Grampositivas/microbiología , Aguas del Alcantarillado/virologíaRESUMEN
BACKGROUND: Lacticaseibacillus (formerly Lactobacillus) rhamnosus is widely used in probiotics or food supplements to promote microbiome health and may also be part of the normal microbiota of the human gastrointestinal tract. However, it rarely also causes invasive or severe infections in patients. It has been postulated that these infections may originate from probiotics or from endogenous commensal reservoirs. In this report, we examine the population structure of Lacticaseibacillus rhamnosus and investigate the utility of using bacterial genomics to identify the source of invasive Lacticaseibacillus infections. METHODS: Core genome phylogenetic analysis was performed on 602 L. rhamnosus genome sequences from the National Center for Biotechnology public database. This information was then used along with newly generated sequences of L. rhamnosus isolates from yogurt to investigate a fatal case of L. rhamnosus endocarditis. RESULTS: Phylogenetic analysis demonstrated substantial genetic overlap of L. rhamnosus isolates cultured from food, probiotics, infected patients, and colonized individuals. This was applied to a patient who had both consumed yogurt and developed L. rhamnosus endocarditis to attempt to identify the source of his infection. The sequence of the isolate from the patient's bloodstream differed at only one nucleotide position from one of the yogurt isolates. Both isolates belonged to a clade, identified here as clade YC, composed of mostly gastrointestinal isolates from healthy individuals, some of which also differed by only a single nucleotide change from the patient's isolate. CONCLUSIONS: As illustrated by this case, whole genome sequencing may be insufficient to reliably determine the source of invasive infections caused by L. rhamnosus.
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Genoma Bacteriano , Lacticaseibacillus rhamnosus , Filogenia , Lacticaseibacillus rhamnosus/genética , Lacticaseibacillus rhamnosus/aislamiento & purificación , Humanos , Probióticos , Masculino , Endocarditis Bacteriana/microbiología , Yogur/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/diagnóstico , Endocarditis/microbiologíaRESUMEN
BACKGROUND: Gram-positive bacteria residing in the nasopharynx can lead to severe illnesses in children, such as otitis media, pneumonia, and meningitis. Despite the potential threat, there is a lack of comprehensive data regarding the carriage rates of these bacteria among children in outpatient departments in the study area. OBJECTIVE: This study aimed to assess the nasopharyngeal carriage, antimicrobial resistance patterns, and associated factors of Gram-positive bacteria among children attending the outpatient department at the University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia. METHODS: A hospital-based cross-sectional study was conducted from May 1, 2023, to August 30, 2023. A total of 424 nasopharyngeal swab samples were collected using sterile nasopharyngeal swabs, inoculated on Blood Agar and Mannitol Salt Agar plates, and identified through colony morphology, Gram stain, and biochemical tests. Antimicrobial susceptibility of the identified bacterial isolates was determined employing both the Kirby-Bauer and modified Kirby-Bauer methods. D-tests were conducted using clindamycin and erythromycin discs to detect inducible clindamycin resistance, while cefoxitin disc tests were utilized to ascertain methicillin resistance. Data entry was executed using Epi-Data version 4.6, and subsequent analysis was performed utilizing SPSS version 25. Bivariable and multivariable logistic regression analyses were employed to identify associated factors. An adjusted odds ratio at a 95% confidence interval with a P-value of < 0.05 was considered statistically significant. RESULTS: The overall nasopharyngeal carriage rate of Gram-positive bacteria was 296/424 (69.8%, 95% CI: 65.3-74.0). Staphylococcus aureus was the most prevalent 122/424 (28.8%), followed by Streptococcus pneumoniae 92/424 (21.7%). Methicillin resistance was observed in 19/122 (15.6%) of S. aureus and 3/60 (5%) of coagulase-negative staphylococcus (CoNS) species. Inducible clindamycin resistance was 10/122 (8.2%) in S. aureus and 4/53 (7.5%) in coagulase-negative staphylococcus species. Multidrug resistance was found in 146/296 (49.3%, 95% CI: 43.6-55.0) of the isolates. Associated factors with a bacterial carriage were large family size (AOR = 3.061, 95% CI: 1.595-5.874, P = 0.001), having siblings under five years old (AOR = 1.991, 95% CI: 1.196-3.313, P = 0.008), indoor cooking (AOR = 2.195, 95% CI: 1.275-3.778, P = 0.005), an illiterate mother (AOR = 3.639, 95% CI: 1.691-7.829, P = 0.001), and hospital visits (AOR = 2.690, 95% CI: 1.405-5.151, P = 0.003). CONCLUSION: The study found a high nasopharyngeal carriage of Gram-positive bacteria in outpatient children, including notable levels of methicillin-resistant S. aureus and multi-drug-resistant isolates. Clindamycin, rifampin, and erythromycin were the most effective antimicrobials for the tested isolates. Factors contributing to bacterial carriage include visits to healthcare facilities, larger family sizes, having younger siblings, maternal illiteracy, and indoor cooking. This emphasizes the need for methicillin-resistant S. aureus surveillance in pediatric outpatient settings and community health education, especially for children's guardians. Additionally, improving household ventilation by separating kitchens from sleeping areas and regular screening of younger siblings in healthcare environments were recommended to reduce bacterial transmission within family members. The study also called for studies with advanced procedures like minimum inhibitory concentration testing and molecular characterization to better comprehend the resistance patterns and genes in circulating bacteria.
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Antibacterianos , Pruebas de Sensibilidad Microbiana , Nasofaringe , Humanos , Etiopía/epidemiología , Femenino , Masculino , Nasofaringe/microbiología , Preescolar , Niño , Estudios Transversales , Lactante , Antibacterianos/farmacología , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/aislamiento & purificación , Pacientes Ambulatorios/estadística & datos numéricos , Portador Sano/microbiología , Portador Sano/epidemiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Farmacorresistencia Bacteriana , Adolescente , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/aislamiento & purificaciónRESUMEN
BACKGROUND: Throughout a three-year study period, 1,577 bovine clinical mastitis samples and 302 bulk tank samples were analyzed from ten Brazilian dairy herds. Enterococcus spp. was isolated and identified in 93 (5.9%) clinical mastitis samples. In addition, 258 Enterococcus spp. were isolated from the bulk tank samples of the same herds. The identification of Enterococcus spp. isolated from bulk tanks and milk samples of clinical mastitis were accomplished by phenotypic characteristics and confirmed by MALDI-TOF Mass Spectrometry (MS). Fisher test was performed to verify the difference between bulk tanks and mastitis samples. RESULTS: The following species were identified from clinical mastitis: E. saccharolyticus (62.4%), E. faecalis (19.4%), E. faecium (15.1%), E. hirae (1.1%), E. mundtii (1.1%), E. durans (1.1%). Furthermore, from 258 bulk tank milk samples, eight enterococci species were isolated: E. faecalis (67.8%), E. hirae (15.1%), E. faecium (4.6%), E. saccharolyticus (4.6%), E. mundtii (3.1%), E. caseliflavus ( 2.7%), E. durans (1.2%), E. galinarum (0.8%). CONCLUSIONS: The difference in species predominance in bulk tank samples (67.8% of E. faecalis) and clinical mastitis (62.4% of E. saccharolyticus) was unexpected and caught our attention. Although Enterococcus spp. are traditionally classified as an environmental mastitis agent, in the present study, E. saccharolyticus behaved as a contagious agent of mastitis, which consequently changed the control patterns to be implemented.
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Enterococcus , Mastitis Bovina , Leche , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Mastitis Bovina/microbiología , Mastitis Bovina/diagnóstico , Animales , Leche/microbiología , Leche/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/veterinaria , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Femenino , Enterococcus/aislamiento & purificación , Bovinos , Brasil , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/diagnósticoRESUMEN
Enterococcus faecalis is one of the main microorganisms that infects root canals, ranking among the most prevalent microorganisms associated with endodontic treatment failure. Given its pervasive presence in persistent endodontic infections, the successful elimination of Enterococcus faecalis is crucial for effective endodontic treatment and retreatment. Furthermore, Enterococcus faecalis can form biofilms - defense structures that microbes use to fight environmental threats. These biofilms confer resistance against host immune system attacks and antibiotic interventions. Consequently, the presence of biofilms poses a significant challenge in the complete eradication of Enterococcus faecalis and its associated disease. In response, numerous scholars have discovered promising outcomes in addressing Enterococcus faecalis biofilms within root canals and undertaken endeavors to explore more efficacious approaches in combating these biofilms. This study provides a comprehensive review of strategies and mechanisms for the removal of Enterococcus faecalis biofilms.
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Biopelículas , Cavidad Pulpar , Enterococcus faecalis , Infecciones por Bacterias Grampositivas , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/fisiología , Humanos , Cavidad Pulpar/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Antibacterianos/farmacologíaRESUMEN
BACKGROUND: Enterococcus gallinarum (EG) is typically found in the gastrointestinal tracts of birds and mammals. Although its strains are rarely isolated from clinical specimens, EG can lead to septicemia in immunocompromised individuals. EG infections are uncommon in household settings, but their incidence has been rising due to increased antibiotic usage and invasive treatments, particularly in Neonatal Intensive Care Units (NICUs). EG inherently exhibits resistance to vancomycin but is highly sensitive to linezolid. Despite showing in vitro resistance, vancomycin has shown clinical efficacy in treating EG meningitis. CASE PRESENTATION: A neonate born at 30 + 2 weeks gestation was admitted to the Neonatal Intensive Care Unit (NICU) after EG was detected in blood and cerebrospinal fluid cultures. Susceptibility testing indicated that the bacterial strain was resistant to vancomycin and sensitive to linezolid. Initially, vancomycin was selected for treatment. However, due to persistent EG cultures in the blood and cerebrospinal fluid, the treatment was adjusted to linezolid. This led to a rapid decrease in platelet (PLT) count, suspected to be an adverse reaction. Concurrently, the patient experienced recurrent fever and elevated inflammatory marker levels, prompting the discontinuation of linezolid and a return to vancomycin. Subsequent administration of vancomycin stabilized the patient's condition, as evidenced by improved C-reactive protein (CRP), procalcitonin (PCT), and cerebrospinal fluid parameters, ultimately leading to discharge after an eight-week treatment period. CONCLUSION: This retrospective analysis highlights the efficacy of vancomycin in treating EG infections, suggesting that specific genetic phenotypes may influence treatment sensitivity. Monitoring vancomycin blood levels is crucial for determining treatment effectiveness.