ABSTRACT
In this study we report the first isolation of VanA-type vancomycin-resistant Enterococcus faecalis strains from two different patients hospitalized in the same intensive care unit at the hospital of Universidade Federal do Triângulo Mineiro (UFTM), Uberaba, Minas Gerais, Brazil.
Subject(s)
Humans , Male , Middle Aged , Enterococcus faecalis/genetics , Enterococcus faecalis/isolation & purification , Gram-Positive Bacterial Infections , In Vitro Techniques , Vancomycin Resistance/genetics , Diagnostic Techniques and Procedures , Genotype , Methods , Patients , Prevalence , VirulenceABSTRACT
In this study we report the first isolation of VanA-type vancomycin-resistant Enterococcus faecalis strains from two different patients hospitalized in the same intensive care unit at the hospital of Universidade Federal do Triângulo Mineiro (UFTM), Uberaba, Minas Gerais, Brazil.
ABSTRACT
OBJECTIVES: To report the isolation of six Staphylococcus hominis subsp. novobiosepticus (SHN) strains from hospitalized patients with bloodstream infections in two Brazilian hospitals and to characterize their susceptibility profile to several antimicrobials. METHODS: Species identification was performed by biochemical methods and sodA gene sequencing. The MICs of antimicrobials were determined by broth and agar dilution methods and by Etest. Isolates were typed by PFGE and PCR amplification was used to detect the ccr gene complex and the mec class. Morphometric evaluation of cell wall was performed by transmission electron microscopy (TEM). RESULTS: Susceptibility profiles indicated that the majority of isolates (five) were multidrug-resistant. Overlapping and multiplex PCR showed that five out of the six strains harboured SCCmec type III with class A mec and type 3 ccr. The initial vancomycin MIC value of 4 mg/L for these strains increased to 16-32 mg/L after growth for 10 days in BHI broth supplemented with this antimicrobial. TEM indicated that vancomycin resistance was associated with cell wall thickening and to another mechanism not fully elucidated. Only one SHN strain was oxacillin- and vancomycin-susceptible. The nosocomial infections in at least five of the patients from both hospitals were caused by a single clone of SHN. CONCLUSIONS: It is very important to consider SHN strains as the cause of nosocomial infections. The clinical implications resulting from the pattern of multidrug resistance in these strains may be complicated by the emergence of vancomycin resistance.
Subject(s)
Bacteremia/microbiology , Cross Infection/microbiology , Staphylococcal Infections/microbiology , Staphylococcus hominis/isolation & purification , Anti-Bacterial Agents/pharmacology , Bacteremia/epidemiology , Bacterial Proteins/genetics , Bacterial Typing Techniques , Brazil/epidemiology , Cell Wall/ultrastructure , Cluster Analysis , Cross Infection/epidemiology , DNA Fingerprinting , Drug Resistance, Multiple, Bacterial , Electrophoresis, Gel, Pulsed-Field , Genotype , Hospitals , Humans , Microbial Sensitivity Tests , Microscopy, Electron, Transmission , Polymerase Chain Reaction , Sequence Analysis, DNA , Staphylococcal Infections/epidemiology , Staphylococcus hominis/classification , Staphylococcus hominis/drug effects , Staphylococcus hominis/genetics , Superoxide Dismutase/geneticsABSTRACT
Three Enterococcus faecalis and one Enterococcus faecium strains were characterized by plasmid profile, pulsed-field gel electrophoresis (PFGE) and determination of antimicrobial minimal inhibitory concentrations. VanA elements were characterized by Long PCR, overlapping PCR and DNA sequencing. Enterococcal strains showed resistance to vancomycin and harbored the vanA gene, and three these were teicoplanin susceptible while one showed intermediate resistance to teicoplanin. Two E. faecalis strains showed indistinguishable PFGE profile while the third was unrelated. E. faecalis strains showed a deletion in the right terminal region of the Tn1546-like element. The E. faecium strain showed an insertion element in the vanXY intergenic region. Mutations in VanA elements were not found. Rearrangements in the VanA element could be responsible for incongruities in genotype and phenotype in these strains.
Subject(s)
Anti-Bacterial Agents/pharmacology , Enterococcus faecalis , Enterococcus faecium , Teicoplanin/pharmacology , Vancomycin/pharmacology , Bacterial Proteins/genetics , Brazil , Carbon-Oxygen Ligases/genetics , DNA, Bacterial/genetics , Electrophoresis, Gel, Pulsed-Field , Enterococcus faecalis/drug effects , Enterococcus faecalis/genetics , Enterococcus faecalis/isolation & purification , Enterococcus faecium/drug effects , Enterococcus faecium/genetics , Enterococcus faecium/isolation & purification , Genotype , Humans , Microbial Sensitivity Tests , Phenotype , Polymerase Chain Reaction , Sequence Analysis, DNA , Vancomycin Resistance/geneticsABSTRACT
Three Enterococcus faecalis and one Enterococcus faecium strains were characterized by plasmid profile, pulsed-field gel electrophoresis (PFGE) and determination of antimicrobial minimal inhibitory concentrations. VanA elements were characterized by Long PCR, overlapping PCR and DNA sequencing. Enterococcal strains showed resistance to vancomycin and harbored the vanA gene, and three these were teicoplanin susceptible while one showed intermediate resistance to teicoplanin. Two E. faecalis strains showed indistinguishable PFGE profile while the third was unrelated. E. faecalis strains showed a deletion in the right terminal region of the Tn1546-like element. The E. faecium strain showed an insertion element in the vanXY intergenic region. Mutations in VanA elements were not found. Rearrangements in the VanA element could be responsible for incongruities in genotype and phenotype in these strains.
Subject(s)
Humans , Anti-Bacterial Agents/pharmacology , Enterococcus faecalis , Enterococcus faecium , Teicoplanin/pharmacology , Vancomycin/pharmacology , Brazil , Bacterial Proteins/genetics , Carbon-Oxygen Ligases/genetics , DNA, Bacterial/genetics , Electrophoresis, Gel, Pulsed-Field , Enterococcus faecalis/drug effects , Enterococcus faecalis/genetics , Enterococcus faecalis/isolation & purification , Enterococcus faecium/drug effects , Enterococcus faecium/genetics , Enterococcus faecium/isolation & purification , Genotype , Microbial Sensitivity Tests , Phenotype , Polymerase Chain Reaction , Sequence Analysis, DNA , Vancomycin Resistance/geneticsABSTRACT
The isolation of vancomycin resistant enterococci (VRE) in Brazil has rapidly increased, following the world wide tendency. We report in the present study the first isolation of vancomycin resistant Enterococcus faecalis (VRE) in the Northeast of Brazil. The four VRE isolates were characterized for antimicrobial susceptibility, genotypic typing by macro restriction of chromosomal DNA followed by pulsed-field gel electrophoresis and for characterization of the Tn1546-like element and plasmid contents. The isolates showed resistance to multiple antibiotics and a single genotype profile, suggesting the dissemination of a single clone among the patients. Tn1546 associated to genetic elements as plasmids shows the importance of infection control measures to avoid the spreading of glycopeptide resistance by conjugative transfer of VanA elements.
Subject(s)
Bacterial Proteins/genetics , Carbon-Oxygen Ligases/genetics , Cross Infection/microbiology , Enterococcus faecalis/genetics , Gram-Positive Bacterial Infections/microbiology , Vancomycin Resistance/genetics , Bacterial Typing Techniques , Brazil , Cross Infection/diagnosis , DNA, Bacterial/analysis , Electrophoresis, Gel, Pulsed-Field , Enterococcus faecalis/drug effects , Enterococcus faecalis/isolation & purification , Genotype , Gram-Positive Bacterial Infections/diagnosis , Humans , Microbial Sensitivity TestsABSTRACT
The isolation of vancomycin resistant enterococci (VRE) in Brazil has rapidly increased, following the world wide tendency. We report in the present study the first isolation of vancomycin resistant Enterococcus faecalis (VRE) in the Northeast of Brazil. The four VRE isolates were characterized for antimicrobial susceptibility, genotypic typing by macro restriction of chromosomal DNA followed by pulsed-field gel electrophoresis and for characterization of the Tn1546-like element and plasmid contents. The isolates showed resistance to multiple antibiotics and a single genotype profile, suggesting the dissemination of a single clone among the patients. Tn1546 associated to genetic elements as plasmids shows the importance of infection control measures to avoid the spreading of glycopetide resistance by conjugative transfer of VanA elements.
Subject(s)
Humans , Bacterial Proteins , Carbon-Oxygen Ligases/genetics , Cross Infection/microbiology , Enterococcus faecalis/genetics , Gram-Positive Bacterial Infections/microbiology , Vancomycin Resistance , Bacterial Typing Techniques , Brazil , Cross Infection/diagnosis , DNA, Bacterial/analysis , Electrophoresis, Gel, Pulsed-Field , Enterococcus faecalis/drug effects , Enterococcus faecalis/isolation & purification , Genotype , Gram-Positive Bacterial Infections/diagnosis , Microbial Sensitivity TestsABSTRACT
This study reports the results about antimicrobial resistance of Enterococcus spp. isolated from intestinal tract of patients from a university hospital in Brazil. The identification of strains at species level was performed by conventional biochemical tests, API 20 Strep (bioMérieux), and polymerase chain reaction assay. The specie distribution was E. faecium (34 percent), followed by E. faecalis (33 percent), E. gallinarum (23.7 percent), E. casseliflavus (5.2 percent), E. avium (1 percent), and E. hirae (1 percent). Intrinsic resistance to vancomycin characterized by presence of vanC genes was found in E. gallinarum and E. casseliflavus. The high prevalence of VanC phenotype enterococci is very important because these species have been reported as causing a wide variety of infections. Vancomycin-resistant E. faecium or E. faecalis were not found and no one isolate of these species was a beta-lactamase producer. Thirteen clinical isolates of enterococci (13.4 percent) showed multiresistance patterns, which were defined by resistance to three classes of antibiotics plus resistance to at least one aminoglycoside (gentamicin and/or streptomycin). The resistance to several antimicrobials shown by enterococcal strains obtained in this study is of concern because of the decrease in the therapeutic options for treatment of infections caused by enterococci.
Subject(s)
Humans , Anti-Bacterial Agents , Drug Resistance, Bacterial , Enterococcus , Gram-Positive Bacterial Infections , Intestinal Diseases , beta-Lactamases , Brazil , Feces , Genotype , Hospitals, University , Microbial Sensitivity Tests , Polymerase Chain Reaction , Vancomycin ResistanceABSTRACT
This study reports the results about antimicrobial resistance of Enterococcus spp. isolated from intestinal tract of patients from a university hospital in Brazil. The identification of strains at species level was performed by conventional biochemical tests, API 20 Strep (bioMérieux), and polymerase chain reaction assay. The species distribution was E. faecium (34%), followed by E. faecalis (33%), E. gallinarum (23.7%), E. casseliflavus (5.2%), E. avium (1%), and E. hirae (1%). Intrinsic resistance to vancomycin characterized by presence of vanC genes was found in E. gallinarum and E. casseliflavus. The high prevalence of VanC phenotype enterococci is very important because these species have been reported as causing a wide variety of infections. Vancomycin-resistant E. faecium or E. faecalis were not found and no one isolate of these species was a beta-lactamase producer. Thirteen clinical isolates of enterococci (13.4%) showed multiresistance patterns, which were defined by resistance to three classes of antibiotics plus resistance to at least one aminoglycoside (gentamicin and/or streptomycin). The resistance to several antimicrobials shown by enterococcal strains obtained in this study is of concern because of the decrease in the therapeutic options for treatment of infections caused by enterococci.
