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1.
BMC Microbiol ; 24(1): 334, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39251908

RESUMEN

BACKGROUND: Characteristics of non-clinical strains of methicillin-resistant Staphylococcus aureus (MRSA) especially from fishery environment are poorly understood. This research, in addition to comprehensive characterisation, sought to delineate the genetic relatedness between the MRSA strains originating from clinical as well as non-clinical settings. Out of 39 methicillin-resistant staphylococcal isolates from 197 fish samples, 6 (Three each of methicillin-resistant S. haemolyticus (MRSH) and MRSA) with distinct resistance profiles were selected for whole-genome sequencing. Using respective bioinformatics tools, MRSA genomes were comprehensively characterized for resistome, virulomes, molecular epidemiology and phylogenetic analysis. Simultaneously, MRSH genomes were specifically examined to characterize antimicrobial resistance genes (ARGs), owing to the fact that MRSH is often recognized as a reservoir for resistance determinants. RESULTS: Three MRSA clones identified in this study include ST672-IVd/t13599 (sequence type-SCCmec type/spa type), ST88-V/t2526, and ST672-IVa/t1309. Though, the isolates were phenotypically vancomycin-sensitive, five of the six genomes carried vancomycin resistance genes including the VanT (VanG cluster) or VanY (VanM cluster). Among the three MRSA, only one harbored the gene encoding Panton-Valentine Leukocidin (PVL) toxin, while staphylococcal enterotoxin (SEs) genes such as sea and seb, associated with staphylococcal food poisoning were identified in two other MRSA. Genomes of MRSH carried a composite of type V staphylococcal cassette chromosome mec (SCCmec) elements (5C2 & 5). This finding may be explained by the inversion and recombination events that may facilitate the integration of type V elements to the SCC elements of S. aureus with a methicillin-susceptible phenotype. Phylogenetically, MRSA from a non-clinical setting displayed a considerable relatedness to that from clinical settings. CONCLUSION: This study highlights the genetic diversity and resistance profiles of MRSA and MRSH, with non-clinical MRSA showing notable relatedness to clinical strains. Future research should explore resistance gene transfer mechanisms and environmental reservoirs to better manage MRSA spread.


Asunto(s)
Peces , Genoma Bacteriano , Staphylococcus aureus Resistente a Meticilina , Filogenia , Intoxicación Alimentaria Estafilocócica , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Animales , Peces/microbiología , Intoxicación Alimentaria Estafilocócica/microbiología , Genoma Bacteriano/genética , Antibacterianos/farmacología , Secuenciación Completa del Genoma , Virulencia/genética , Pruebas de Sensibilidad Microbiana , Humanos , Factores de Virulencia/genética , Alimentos Marinos/microbiología , Microbiología de Alimentos , Toxinas Bacterianas/genética , Epidemiología Molecular , Staphylococcus haemolyticus/genética , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/aislamiento & purificación , Staphylococcus haemolyticus/patogenicidad
2.
Res Vet Sci ; 177: 105365, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39053094

RESUMEN

Staphylococci are classified as one of the pathogens causing bovine mastitis that can pose not only an economic loss to the dairy farms, but a serious public-health threat based on their zoonotic potential. We focused to monitor phenotypes of the isolated strains of Staphylococcus aureus (S. aureus) and Staphylococcus haemolyticus (S. haemolyticus) from milk of cows with clinical mastitis, including antibiotic resistance, biofilm forming ability and the presence of biofilm- and toxin- related genes. From a total of 191 milk samples were identified as S. aureus - 12% (22 isolates) and S. haemolyticus - 6% (12 isolates). Automatic interpreted reading of the antibiogram evaluated potentially 12 isolates as methicillin-resistant S. aureus and methicillin-resistant coagulase-negative Staphylococci. Genotypically, the isolates were positive for blaZ and negative for mecA and mecC. Others important mechanisms were inducible macrolide-lincosamide-streptogramin B (iMLSB) resistance with presence of msrA, ermC, vgaA. The most detected biofilm-associated and toxins genes were clfA, sdrD, sdrE, fnbpB, bbp, isdA, isdB, hla and see. S. aureus isolates were subjected to spa typing. It turned out that despite the strains coming from different farms, they were either resistant or sensitive to antibiotic, were all of the same spa-type t 10035. Our findings revealed the presence iMLSB, which, to our best knowledge, were described in Slovakian bovine staphylococci rarely. The majority of isolates were multidrug-resistant and carried multiple virulence genes, posing a potential public-health risk.


Asunto(s)
Antibacterianos , Biopelículas , Mastitis Bovina , Infecciones Estafilocócicas , Staphylococcus aureus , Staphylococcus haemolyticus , Animales , Bovinos , Mastitis Bovina/microbiología , Femenino , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/genética , Staphylococcus haemolyticus/aislamiento & purificación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/genética , Infecciones Estafilocócicas/veterinaria , Infecciones Estafilocócicas/microbiología , Biopelículas/efectos de los fármacos , Antibacterianos/farmacología , Leche/microbiología , Pruebas de Sensibilidad Microbiana/veterinaria , Farmacorresistencia Bacteriana/genética
3.
Microb Pathog ; 192: 106724, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38834135

RESUMEN

Staphylococcus haemolyticus is a cause of bovine mastitis, leading to inflammation in the mammary gland. This bacterial infection adversely affects animal health, reducing milk quality and yield. Its emergence has been widely reported, representing a significant economic loss for dairy farms. Interestingly, S. haemolyticus exhibits higher levels of antimicrobial resistance than other coagulase-negative Staphylococci. In this study, we synthesized silver/silver chloride nanoparticles (Ag/AgCl-NPs) using Solanum lasiocarpum root extract and evaluated their antibacterial and antibiofilm activities against S. haemolyticus. The formation of the Ag/AgCl-NPs was confirmed using UV-visible spectroscopy, which revealed maximum absorption at 419 nm. X-ray diffraction (XRD) analysis demonstrated the crystalline nature of the Ag/AgCl-NPs, exhibiting a face-centered cubic lattice. Fourier transform infrared (FT-IR) spectroscopy elucidated the functional groups potentially involved in the Ag/AgCl-NPs synthesis. Transmission electron microscopy (TEM) analysis revealed that the average particle size of the Ag/AgCl-NPs was 10 nm. Antimicrobial activity results indicated that the minimum inhibitory concentration (MIC) and maximum bactericidal concentration (MBC) of the Ag/AgCl-NPs treatment were 7.82-15.63 µg/mL towards S. haemolyticus. Morphological changes in bacterial cells treated with the Ag/AgCl-NPs were observed under scanning electron microscopy (SEM). The Ag/AgCl-NPs reduced both the biomass of biofilm formation and preformed biofilm by approximately 20.24-94.66 % and 13.67-88.48 %. Bacterial viability within biofilm formation and preformed biofilm was reduced by approximately 21.56-77.54 % and 18.9-71.48 %, respectively. This study provides evidence of the potential of the synthesized Ag/AgCl-NPs as an antibacterial and antibiofilm agent against S. haemolyticus.


Asunto(s)
Antibacterianos , Biopelículas , Mastitis Bovina , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Raíces de Plantas , Compuestos de Plata , Plata , Solanum , Staphylococcus haemolyticus , Animales , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antibacterianos/farmacología , Antibacterianos/química , Plata/farmacología , Plata/química , Biopelículas/efectos de los fármacos , Compuestos de Plata/farmacología , Compuestos de Plata/química , Bovinos , Mastitis Bovina/microbiología , Mastitis Bovina/tratamiento farmacológico , Raíces de Plantas/química , Nanopartículas del Metal/química , Staphylococcus haemolyticus/efectos de los fármacos , Femenino , Solanum/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Microscopía Electrónica de Transmisión
4.
Emerg Microbes Infect ; 13(1): 2353291, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38738561

RESUMEN

An emergence of multidrug-resistant (MDR) Staphylococcus haemolyticus has been observed in the neonatal intensive care unit (NICU) of Nîmes University Hospital in southern France. A case-control analysis was conducted on 96 neonates, to identify risk factors associated with S. haemolyticus infection, focusing on clinical outcomes. Forty-eight MDR S. haemolyticus strains, isolated from neonates between October 2019 and July 2022, were investigated using routine in vitro procedures and whole-genome sequencing. Additionally, five S. haemolyticus isolates from adult patients were sequenced to identify clusters circulating within the hospital environment. The incidence of neonatal S. haemolyticus was significantly associated with low birth weight, lower gestational age, and central catheter use (p < 0.001). Sepsis was the most frequent clinical manifestation in this series (20/46, 43.5%) and was associated with five deaths. Based on whole-genome analysis, three S. haemolyticus genotypes were predicted: ST1 (6/53, 11%), ST25 (3/53, 5.7%), and ST29 (44/53, 83%), which included the subcluster II-A, predominantly emerging in the neonatal department. All strains were profiled in silico to be resistant to methicillin, erythromycin, aminoglycosides, and fluoroquinolones, consistent with in vitro antibiotic susceptibility tests. Moreover, in silico prediction of biofilm formation and virulence-encoding genes supported the association of ST29 with severe clinical outcomes, while the persistence in the NICU could be explained by the presence of antiseptic and heavy metal resistance-encoding genes. The clonality of S. haemolyticus ST29 subcluster II-A isolates confirms healthcare transmission causing severe infections. Based on these results, reinforced hygiene measures are necessary to eradicate the nosocomial transmission of MDR strains.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Unidades de Cuidado Intensivo Neonatal , Infecciones Estafilocócicas , Staphylococcus haemolyticus , Secuenciación Completa del Genoma , Humanos , Staphylococcus haemolyticus/genética , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/aislamiento & purificación , Staphylococcus haemolyticus/clasificación , Francia/epidemiología , Recién Nacido , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/epidemiología , Farmacorresistencia Bacteriana Múltiple/genética , Femenino , Masculino , Antibacterianos/farmacología , Estudios de Casos y Controles , Pruebas de Sensibilidad Microbiana , Infección Hospitalaria/microbiología , Infección Hospitalaria/epidemiología , Genotipo , Factores de Riesgo , Genoma Bacteriano
5.
Microbiol Res ; 282: 127652, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38432015

RESUMEN

Staphylococcus haemolyticus, a key species of the Staphylococcus genus, holds significant importance in healthcare-associated infections, due to its notable resistance to antimicrobials, like methicillin, and proficient biofilms-forming capabilities. This coagulase-negative bacterium poses a substantial challenge in the battle against nosocomial infections. Recent research has shed light on Staph. haemolyticus genomic plasticity, unveiling genetic elements responsible for antibiotic resistance and their widespread dissemination within the genus. This review presents an updated and comprehensive overview of the clinical significance and prevalence of Staph. haemolyticus, underscores its zoonotic potential and relevance in the one health framework, explores crucial virulence factors, and examines genetics features contributing to its success in causing emergent and challenging infections. Additionally, we scrutinize ongoing studies aimed at controlling spread and alternative approaches for combating it.


Asunto(s)
Infección Hospitalaria , Infecciones Estafilocócicas , Humanos , Staphylococcus haemolyticus/genética , Infección Hospitalaria/microbiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Virulencia/genética , Farmacorresistencia Bacteriana/genética , Infecciones Estafilocócicas/microbiología , Pruebas de Sensibilidad Microbiana
6.
J Infect Public Health ; 17(1): 18-24, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37992430

RESUMEN

BACKGROUND: Staphylococcus haemolyticus belongs to the Coagulase-Negative Staphylococci (CoNS), exhibiting the highest levels of antibiotic resistance within this group of bacteria. This species has been increasingly implicated in nosocomial and animal infections worldwide, with a prevalence of methicillin-resistant Staphylococcus haemolyticus (MRSH). Most information about this organism comes from regional analyzes or with the absence of typing data, thus not revealing the real role of S. haemolyticus strains in world public health. METHODS: Here, we performed an enhanced global epidemiological analysis considering all available S. haemolyticus genomes from all continents, including genomes of nosocomial, environmental, and animal origin (n = 310). Furthermore, we added original genomic information from a clinical MRSH from the Brazilian Amazon region. The resistome and virulome of the genomes were associated with their mobilome, being inferred based on the presence of specific genes and databases such as CARD, VFDB, and PlasmidFinder, respectively. RESULTS: Phylogenetic analysis revealed three main groups, the main one covering most of the clinical clonal complex 3 (CC3) genomes in the world. The virulome of some genomes in this cluster showed the complete capsule operon (capA-capM). Importantly, this virulome trait could be associated with the mobilome, since the capsule operon, as well as a whole set of genes of the type VII secretion system, were observed in plasmids. In addition, the resistome of the main cluster (CC3) was larger, characterized mainly by the presence of the mecA gene, in addition to a set of other genes (aad, aac-aph, aph, erm), contrasting with the poor resistome of the other two clusters. Several insertion sequences were identified, some of them linked to specific clusters, and resistance genes, such as the rare cfrA (IS257). CONCLUSIONS: Therefore, successful lineages of CC3 S. haemolyticus causing human infections are widespread worldwide, raising concern about the impact of this scenario on public health.


Asunto(s)
Infección Hospitalaria , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Humanos , Staphylococcus haemolyticus/genética , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Filogenia , Staphylococcus/genética , Genómica , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana
8.
Microbiol Spectr ; 11(6): e0086923, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37905822

RESUMEN

IMPORTANCE: Bacteria produce bacteriocins to inhibit growth of other bacterial species. We have studied the antimicrobial activity of a new bacteriocin produced by the skin bacterium S. haemolyticus. The bacteriocin is effective against several types of Gram-positive bacteria, including highly virulent and antibiotic-resistant strains such as Staphylococcus aureus and Enterococcus faecium. Effective antimicrobials are important for the treatment of infections and the success of major surgery and chemotherapy. Bacteriocins can be part of the solution to the global concern of antimicrobial resistance.


Asunto(s)
Antiinfecciosos , Bacteriocinas , Bacteriocinas/farmacología , Staphylococcus haemolyticus , Antibacterianos/farmacología , Organización Mundial de la Salud
9.
Sci Rep ; 13(1): 18646, 2023 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-37903798

RESUMEN

Three stable microbial consortia, each composed of Bacillus paranthracis and Staphylococcus haemolyticus strains, were isolated from milk of cows diagnosed with mastitis in three geographically remote regions of Russia. The composition of these consortia remained stable following multiple passages on culture media. Apparently, this stability is due to the structure of the microbial biofilms formed by the communities. The virulence of the consortia depended on the B. paranthracis strains. It seems plausible that the ability of the consortia to cause mastitis in cattle was affected by mutations of the cytK gene of B. paranthracis.


Asunto(s)
Mastitis Bovina , Infecciones Estafilocócicas , Femenino , Animales , Bovinos , Humanos , Staphylococcus haemolyticus/genética , Infecciones Estafilocócicas/veterinaria , Leche , Genómica
10.
J Med Microbiol ; 72(7)2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37477411

RESUMEN

Introduction. Linezolid is an effective therapeutic option for treating severe infections caused by multidrug-resistant Gram-positive organisms. Several mechanisms have been reported to be responsible for resistance to this antibiotic.Hypothesis or Gap Statement. Although several mechanisms of linezolid resistance have been reported in Staphylococcus haemolyticus, the prevalence and potential for horizontal transfer of resistance genes have not been fully characterized, particularly among S. haemolyticus isolates from India.Aim. To perform whole-genome sequencing (WGS) of linezolid-resistant S. haemolyticus isolates to characterize the resistance mechanisms.Methodology. WGS was performed for 16 linezolid-resistant S. haemolyticus isolates to check for the presence of cfr, optrA and poxtA genes and mutations in 23S rRNA and ribosomal proteins (L3, L4 and L22) that are possible mechanisms implicated in linezolid resistance. Sequence types were identified using MLST finder. The minimum inhibitory concentration (MIC) of linezolid was determined using the E-test method. Polymerase chain reaction (PCR) was carried out for the detection of the cfr gene.Results. The study documented three different mechanisms of linezolid resistance in S. haemolyticus. Thirteen of the 16 isolates were phenotypically resistant to linezolid, of which 12 were positive for the cfr gene. The G2603T mutation in 23S rRNA was found in the majority of the isolates (n=13). Ten isolates had the R138V mutation in L3 ribosomal protein. Twelve isolates with the cfr gene in combination with either G2603T or R138V mutations displayed extremely high MIC values. Surprisingly, three phenotypically sensitive isolates were found to be positive for the cfr gene but negative for other resistance mechanisms. Importantly, in almost half of the isolates the cfr gene was present on a plasmid. ST3 and ST1 were found to be the predominant sequence types.Conclusion. All phenotypically resistant isolates exhibited two or three linezolid resistance mechanisms. The cfr gene was found on plasmids in many isolates, demonstrating its potential for horizontal transfer to more pathogenic organisms.


Asunto(s)
ARN Ribosómico 23S , Staphylococcus haemolyticus , Linezolid/farmacología , Staphylococcus haemolyticus/genética , Tipificación de Secuencias Multilocus , ARN Ribosómico 23S/genética , Farmacorresistencia Bacteriana/genética , Antibacterianos/farmacología , Enterococcus , Pruebas de Sensibilidad Microbiana
11.
Anal Chim Acta ; 1273: 341534, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37423664

RESUMEN

Staphylococcus haemolyticus (S. haemolyticus), which is highly prevent in the hospital environment, is an etiological factor for nosocomial infections. Point-of-care rapid testing (POCT) of S. haemolyticus is not possible with the currently used detection methods. Recombinase polymerase amplification (RPA) is a novel isothermal amplification technology with high sensitivity and specificity. The combination of RPA and lateral flow strips (LFS) can achieve rapid pathogen detection, enabling POCT. This study developed an RPA-LFS methodology using a specific probe/primer pair to identify S. haemolyticus. A basic RPA reaction was performed to screen the specific primer from 6 primer pairs targeting mvaA gene. The optimal primer pair was selected based on agarose gel electrophoresis, and the probe was designed. To eliminate false-positive results caused by the byproducts, base mismatches were introduced in the primer/probe pair. The improved primer/probe pair could specifically identify the target sequence. To explore the optimal reaction conditions, the effects of reaction temperature and duration of the RPA-LFS method were systematically investigated. The improved system enabled optimal amplification at 37 °C for 8 min, and the results were visualized within 1 min. The S. haemolyticus detection sensitivity of the RPA-LFS method, whose performance was unaffected by contamination with other genomes, was 0.147 CFU/reaction. Furthermore, we analyzed 95 random clinical samples with RPA-LFS, quantitative polymerase chain reaction (qPCR), and traditional bacterial-culture assays and found that the RPA-LFS had 100% and 98.73% compliance rates with the qPCR and traditional culture method, respectively, which confirms its clinical applicability. In this study, we designed an improved RPA-LFS assay based on the specific probe/primer pair for the detection of S. haemolyticus via rapid POCT, free from the limitations of the precision instruments, helping to make diagnoses and treatment decisions as soon as possible.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico , Recombinasas , Recombinasas/genética , Técnicas de Amplificación de Ácido Nucleico/métodos , Staphylococcus haemolyticus/genética , Sensibilidad y Especificidad
12.
Front Cell Infect Microbiol ; 13: 1183390, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37265496

RESUMEN

Introduction: Non-aureus Staphylococcus (NAS) species are currently the most commonly identified microbial agents causing sub-clinical infections of the udder and are also deemed as opportunistic pathogens of clinical mastitis in dairy cattle. More than 10 NAS species have been identified and studied but little is known about S. haemolyticus in accordance with dairy mastitis. The present study focused on the molecular epidemiology and genotypic characterization of S. haemolyticus isolated from dairy cattle milk in Northwest, China. Methods: In this study, a total of 356 milk samples were collected from large dairy farms in three provinces in Northwest, China. The bacterial isolation and presumptive identification were done by microbiological and biochemical methods following the molecular confirmation by 16S rRNA gene sequencing. The antimicrobial susceptibility testing (AST) was done by Kirby-Bauer disk diffusion assay and antibiotic-resistance genes (ARGs) were identified by PCR. The phylogenetic grouping and sequence typing was done by Pulsed Field Gel Electrophoresis (PFGE) and Multi-Locus Sequence Typing (MLST) respectively. Results: In total, 39/356 (11.0%) were identified as positive for S. haemolyticus. The overall prevalence of other Staphylococcus species was noted to be 39.6% (141/356), while the species distribution was as follows: S. aureus 14.9%, S. sciuri 10.4%, S. saprophyticus 7.6%, S. chromogenes 4.2%, S. simulans 1.4%, and S. epidermidis 1.1%. The antimicrobial susceptibility of 39 S. haemolyticus strains exhibited higher resistance to erythromycin (92.3%) followed by trimethoprim-sulfamethoxazole (51.3%), ciprofloxacin (43.6%), florfenicol (30.8%), cefoxitin (28.2%), and gentamicin (23.1%). All of the S. haemolyticus strains were susceptible to tetracycline, vancomycin, and linezolid. The overall percentage of multi-drug resistant (MDR) S. haemolyticus strains was noted to be 46.15% (18/39). Among ARGs, mphC was identified as predominant (82.05%), followed by ermB (33.33%), floR (30.77%), gyrA (30.77%), sul1 (28.21%), ermA (23.08%), aadD (12.82%), grlA (12.82%), aacA-aphD (10.26%), sul2 (10.26%), dfrA (7.69%), and dfrG (5.13%). The PFGE categorized 39 S. haemolyticus strains into A-H phylogenetic groups while the MLST categorized strains into eight STs with ST8 being the most predominant while other STs identified were ST3, ST11, ST22, ST32, ST19, ST16, and ST7. Conclusion: These findings provided new insights into our understanding of the epidemiology and genetic characteristics of S. haemolyticus in dairy farms to inform interventions limiting the spread of AMR in dairy production.


Asunto(s)
Mastitis Bovina , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Femenino , Bovinos , Animales , Staphylococcus haemolyticus/genética , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus/genética , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/veterinaria , Infecciones Estafilocócicas/microbiología , Tipificación de Secuencias Multilocus , Epidemiología Molecular , Leche , Filogenia , ARN Ribosómico 16S/genética , Mastitis Bovina/epidemiología , Mastitis Bovina/microbiología , Staphylococcus , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana
13.
Microb Pathog ; 180: 106152, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37178725

RESUMEN

OBJECTIVES: This study aimed to determine the inhibitory and bactericidal effects of teicoplanin (TEC) on TEC-susceptible Staphylococcus haemolyticus isolated from a patient with cancer in whom infection persisted despite TEC therapy. We also focused on the biofilm-forming ability of the isolate in vitro. METHODS: S. haemolyticus clinical isolate (strain 1369A) and its control strain, ATCC 29970 were cultured in Luria-Bertani (LB) broth with TEC. The inhibitory and bactericidal effects of TEC on planktonic, adherent, biofilm-dispersed, and biofilm-embedded cells of these strains were analyzed by using a biofilm formation/viability assay kit. The expression of biofilm-related genes was measured using quantitative real-time polymerase chain reaction (qRT-PCR). Biofilm formation was determined by using scanning electron microscopy (SEM). RESULTS: The clinical isolate of S. haemolyticus had enhanced ability to bacterial growth, adherence, aggregation, and biofilm formation, thus the inhibitory and bactericidal effects of TEC on planktonic, adherent, biofilm-dispersed, and biofilm-embedded cells of the isolate were attenuated. Additionally, TEC induced cell aggregation, biofilm formation, and some biofilm-related gene expression of the isolate. CONCLUSION: The clinical isolate of S. haemolyticus is resistant to TEC treatment due to cell aggregation and biofilm formation.


Asunto(s)
Infecciones Estafilocócicas , Teicoplanina , Humanos , Teicoplanina/farmacología , Staphylococcus haemolyticus/genética , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Antibacterianos/farmacología , Biopelículas , Pruebas de Sensibilidad Microbiana
14.
Future Microbiol ; 18: 407-414, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37213139

RESUMEN

Background: Staphylococcus haemolyticus is an emerging threat in the nosocomial environment but only some virulence factors are known. Materials & methods: The frequency of the sasX gene (or orthologues sesI/shsA), encoding an invasiveness-related surface-associated protein, in S. haemolyticus was detected in different hospitals in Rio de Janeiro. Results: 9.4% of strains were sasX/sesI/shsA-positive, some were in the context of the ΦSPß-like prophage and devoid of CRISPR systems, indicating potential transferability of their virulence genes. Gene sequencing evidenced that Brazilian S. haemolyticus harbored sesI, instead of the usual sasX, while S. epidermidis had sasX instead of sesI, suggesting horizontal acquisition. Conclusion: The contexts of Brazilian sasX/sesI/shsA favor transfer, which is alarming given the difficulty in treating infections caused by S. haemolyticus.


Asunto(s)
Infección Hospitalaria , Infecciones Estafilocócicas , Humanos , Staphylococcus haemolyticus/genética , Virulencia/genética , Brasil/epidemiología , Infección Hospitalaria/epidemiología , Infecciones Estafilocócicas/epidemiología , Staphylococcus epidermidis/genética , Hospitales , Antibacterianos
15.
J Dairy Sci ; 106(6): 4214-4231, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37080785

RESUMEN

To effectively prevent and control bovine mastitis, farmers and their advisors need to take infection pathways and durations into account. Still, studies exploring both aspects through molecular epidemiology with sampling of entire dairy cow herds over longer periods are scarce. Therefore, quarter foremilk samples were collected at 14-d intervals from all lactating dairy cows (n = 263) over 18 wk in one commercial dairy herd. Quarters were considered infected with Staphylococcus aureus, Streptococcus uberis, or Streptococcus dysgalactiae when ≥100 cfu/mL of the respective pathogen was detected, or with Staphylococcus epidermidis or Staphylococcus haemolyticus when ≥500 cfu/mL of the respective pathogen was detected. All isolates of the mentioned species underwent randomly amplified polymorphic DNA (RAPD)-PCR to explore strain diversity and to distinguish ongoing from new infections. Survival analysis was used to estimate infection durations. Five different strains of Staph. aureus were isolated, and the most prevalent strain caused more than 80% of all Staph. aureus infections (n = 46). In contrast, 46 Staph. epidermidis and 69 Staph. haemolyticus strains were isolated, and none of these caused infections in more than 2 different quarters. The 3 most dominant strains of Strep. dysgalactiae (7 strains) and Strep. uberis (18 strains) caused 81% of 33 and 49% of 37 infections in total, respectively. The estimated median infection duration for Staph. aureus was 80 d, and that for Staph. epidermidis and Staph. haemolyticus was 28 and 22 d, respectively. The probability of remaining infected with Strep. dysgalactiae or Strep. uberis for more than 84 and 70 d was 58.7 and 53.5%, respectively. Staphylococcus epidermidis and Staph. haemolyticus were not transmitted contagiously and the average infection durations were short, which brings into question whether antimicrobial treatment of intramammary infections with these organisms is justified. In contrast, infections with the other 3 pathogens lasted longer and largely originated from contagious transmission.


Asunto(s)
Enfermedades de los Bovinos , Mastitis Bovina , Infecciones Estafilocócicas , Infecciones Estreptocócicas , Femenino , Bovinos , Animales , Staphylococcus , Lactancia , Técnica del ADN Polimorfo Amplificado Aleatorio/veterinaria , Leche/metabolismo , Streptococcus , Staphylococcus aureus , Infecciones Estreptocócicas/veterinaria , Infecciones Estreptocócicas/metabolismo , Infecciones Estafilocócicas/veterinaria , Infecciones Estafilocócicas/metabolismo , Mastitis Bovina/epidemiología , Staphylococcus haemolyticus , Enfermedades de los Bovinos/metabolismo
16.
Int J Mol Sci ; 24(7)2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37047168

RESUMEN

Multi-drug resistant Staphylococcus haemolyticus is a frequent nosocomial invasive bacteremia pathogen in hospitals. Our previous analysis showed one of the predominant strains, ST42 originated from ST3, had only one multilocus sequence typing (MLST) variation among seven loci in SH1431; yet no significant differences in biofilm formation observed between ST42 and ST3, suggesting that other factors influence clonal lineage change. Whole genome sequencing was conducted on two isolates from ST42 and ST3 to find phenotypic and genotypic variations, and these variations were further validated in 140 clinical isolates. The fusidic acid- and tetracycline-resistant genes (fusB and tetK) were found only in CGMH-SH51 (ST42). Further investigation revealed consistent resistant genotypes in all isolates, with 46% and 70% of ST42 containing fusB and tetK, respectively. In contrast, only 23% and 4.2% ST3 contained these two genes, respectively. The phenotypic analysis also showed that ST42 isolates were highly resistant to fusidic acid (47%) and tetracycline (70%), compared with ST3 (23% and 4%, respectively). Along with drug-resistant genes, three capsule-related genes were found in higher percentage distributions in ST42 than in ST3 isolates. Our findings indicate that ST42 could become endemic in Taiwan, further constitutive surveillance is required to prevent the spread of this bacterium.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Ácido Fusídico/farmacología , Staphylococcus haemolyticus/genética , Tipificación de Secuencias Multilocus , Farmacorresistencia Bacteriana/genética , Antibacterianos/farmacología , Tetraciclina , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/microbiología
17.
Vet Dermatol ; 34(4): 298-309, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36908239

RESUMEN

BACKGROUND: Staphylococcus haemolyticus is a coagulase-negative commensal organism of both people and companion animals. It has pathogenic potential and when cultured is often meticillin- and multidrug-resistant. OBJECTIVES: To characterise the clinical features of dogs and cats with clinical skin disease that had positive S. haemolyticus skin cultures, and to employ whole-genome sequencing (WGS) to identify resistance genes and characterise the genetic relatedness of strains. MATERIALS AND METHODS: Isolates were identified by the institutional clinical microbiology laboratory by routine aerobic culture and susceptibility from seven veterinary hospitals across the United States. Then, WGS and analysis of each isolate were performed and clinical data collected via a retrospective clinician questionnaire. RESULTS: S. haemolyticus was identified from superficial (seven of 12) and deep (five of 12) cutaneous infections in our study. Most animals had received antimicrobials (10 of 12) and/or immunomodulatory drugs (nine of 12) within the six months before culture. WGS analysis revealed a variety of genetic lineages and a wide array of antimicrobial resistance genes. Meticillin resistance was identified in nine of 12 isolates and four of 12 isolates demonstrated mupirocin tolerance. CONCLUSIONS AND CLINICAL RELEVANCE: Staphylococcus haemolyticus may be an under-recognised pathogen in companion animals, and its demonstrated potential for multidrug-resistance, meticillin-resistance, and high-level mupirocin tolerance may create a therapeutic challenge. Further studies should evaluate the prior antimicrobial use and immunocompromised status as risk factors for infection with S. haemolyticus.


Asunto(s)
Enfermedades de los Gatos , Enfermedades de los Perros , Infecciones Estafilocócicas , Gatos , Perros , Animales , Estados Unidos/epidemiología , Mupirocina/farmacología , Mupirocina/uso terapéutico , Staphylococcus haemolyticus/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Meticilina , Enfermedades de los Gatos/tratamiento farmacológico , Enfermedades de los Gatos/microbiología , Estudios Retrospectivos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/veterinaria , Infecciones Estafilocócicas/microbiología , Pruebas de Sensibilidad Microbiana/veterinaria , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/microbiología , Genómica
18.
BMC Infect Dis ; 23(1): 95, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36788492

RESUMEN

BACKGROUND: Coagulase-negative staphylococci can cause hospital-acquired infections, especially in immunocompromised hosts. Bacterial meningitis is a potentially fatal infection of the central nervous system, causing high mortality and morbidity. In general, the causative agents of meningitis, coagulase-negative staphylococci, are associated with direct implantation of a foreign body and the presence of a cerebrospinal fluid (CSF) shunt. Here, we describe a case of nosocomial meningitis caused by Staphylococcus haemolyticus in a child with neutropenia who had no intracranial foreign devices. CASE PRESENTATION: A 15-year-old boy with relapsed acute myeloid leukemia undergoing chemotherapy through a central venous catheter developed fever on Day 13 post-initiation of chemotherapy. There was no history of implantation of neurosurgical devices. Two blood cultures obtained on Day 14 were positive for Staphylococcus haemolyticus. Clinical improvement was noted, and treatment with vancomycin and removal of the central venous catheter resulted in negative repeat blood cultures on Day 18. However, the patient developed a tendency for somnolence and improper speech, along with persistent fever on Day 26. A lumber puncture was performed on Day 27, resulting in positive culture of Staphylococcus haemolyticus. He was diagnosed with meningitis and the dosage of vancomycin was increased. A repeat CSF culture was positive for Staphylococcus haemolyticus on Day 40, so oral rifampicin was added. CSF findings on Day 46 revealed a low concentration of vancomycin, and treatment was switched from vancomycin plus rifampicin to linezolid. After Day 46, four subsequent cerebrospinal fluid tests of the CSF showed no growth of Staphylococcus haemolyticus. The patient's symptoms were improved on Day 52. Brain and spinal magnetic resonance images was taken and it showed no abnormalities. Linezolid was continued until Day 72. The patient was discharged without any complications on Day 72. CONCLUSIONS: To the best of our knowledge, this is the first reported case of Staphylococcus haemolyticus meningitis in a patient without a neurosurgical device. Typical symptoms or signs may be absent in a patient with meningitis who also has neutropenia. Repeated tests of the CSF, and prolonged duration of antibiotics should be considered if atypical pathogens are detected in immunocompromised hosts.


Asunto(s)
Infección Hospitalaria , Meningitis Bacterianas , Neutropenia , Infecciones Estafilocócicas , Masculino , Humanos , Niño , Adolescente , Linezolid/uso terapéutico , Vancomicina/uso terapéutico , Staphylococcus haemolyticus , Infección Hospitalaria/microbiología , Rifampin/uso terapéutico , Coagulasa , Antibacterianos/uso terapéutico , Staphylococcus , Neutropenia/complicaciones , Meningitis Bacterianas/complicaciones , Meningitis Bacterianas/diagnóstico , Meningitis Bacterianas/tratamiento farmacológico , Hospitales , Infecciones Estafilocócicas/complicaciones , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/tratamiento farmacológico
19.
Res Vet Sci ; 156: 95-103, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36796241

RESUMEN

Staphylococcus haemolyticus (S. haemolyticus) is one of the most common coagulase-negative staphylococci (CoNS) isolates from bovine mastitis. Paeoniflorin (PF) shows anti-inflammatory effects on different inflammatory diseases in vitro studies and in vivo animal experiments. In this study, the viability of bovine mammary epithelial cells (bMECs) was detected by the cell counting kit-8 experiment. Subsequently, bMECs were induced with S. haemolyticus, and the induction dosage was determined. The expression of pro-inflammatory cytokines and toll-like receptor (TLR2) and nuclear factor kappa-B (NF-κB) signaling pathway-related genes were investigated by quantitative real-time PCR. The critical pathway proteins were detected by western blot. The results showed that the multiplicity of infection (MOI; the ratio of bacteria to bMECs) 5:1 of S. haemolyticus for 12 h could cause cellular inflammation, which was selected to establish the inflammatory model. Incubation with 50 µg/ml PF for 12 h was the best intervention condition for cells stimulated by S. hemolyticus. Quantitative real-time PCR and western blot analysis showed that PF inhibited the activation of TLR2 and NF-κB pathway-related genes and the expression of related proteins. Western blot results showed that PF suppressed the expression of NF-κB unit p65, NF-κB unit p50, and MyD88 in bMECs stimulated by S. haemolyticus. The inflammatory response pathway and molecular mechanism caused by S. haemolyticus on bMECs are related to TLR2-mediated NF-κB signaling pathways. The anti-inflammatory mechanism of PF may also be through this pathway. Therefore, PF is expected to develop potential drugs against CoNS-induced bovine mastitis.


Asunto(s)
Enfermedades de los Bovinos , Mastitis Bovina , Femenino , Animales , Bovinos , FN-kappa B/metabolismo , Receptor Toll-Like 2/genética , Staphylococcus haemolyticus/metabolismo , Mastitis Bovina/microbiología , Transducción de Señal , Inflamación/veterinaria , Receptores Toll-Like , Antiinflamatorios/farmacología , Células Epiteliales/metabolismo , Glándulas Mamarias Animales/metabolismo
20.
Braz J Biol ; 82: e251140, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36651457

RESUMEN

Staphylococcus spp. represents the main mastitis agents in ruminants and contaminants of milk due to their expressive capacity to make biofilms. The aims in this study was evaluate evaluated the antimicrobial activity of Mauritia flexuosa L. extracts against Staphylococcus spp. adhered to a stainless steel surface. Two isolates from cows with clinical mastitis were evaluated; one was identified as Staphylococcus aureus, and the other Staphylococcus haemolyticus. Additionally the ATCC 25923 strain, S. aureus from human was evaluated. The chemical profile obtained from gas chromatography revealed the presence of carbohydrates, organic acids, and flavonoids. The minimum bactericidal concentrations of the ethanolic extract (EE) and aqueous extract (AE) were 4.4 and 5.82 mg/mL, respectively. After EE treatment at 4.4 mg/mL for 2.5 min, total removal of mature biofilms grown on stainless steel coupons was observed (reduction by 3.85-4.81 log units). This extract from M. flexuosa shows potential as an effective sanitizer and may represent a natural alternative against Staphylococcus spp.


Asunto(s)
Infecciones Estafilocócicas , Staphylococcus aureus , Femenino , Humanos , Bovinos , Animales , Staphylococcus haemolyticus , Acero Inoxidable/farmacología , Staphylococcus , Infecciones Estafilocócicas/tratamiento farmacológico , Biopelículas , Extractos Vegetales/farmacología
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