RESUMO
Lipoprotein synthesis is controlled by estrogens, but the exact mechanisms underpinning this regulation and the role of the hepatic estrogen receptor α (ERα) in cholesterol physiology are unclear. Utilizing a mouse model involving selective ablation of ERα in the liver, we demonstrate that hepatic ERα couples lipid metabolism to the reproductive cycle. We show that this receptor regulates the synthesis of cholesterol transport proteins, enzymes for lipoprotein remodeling, and receptors for cholesterol uptake. Additionally, ERα is indispensable during proestrus for the generation of high-density lipoproteins efficient in eliciting cholesterol efflux from macrophages. We propose that a specific interaction with liver X receptor α (LXRα) mediates the broad effects of ERα on the hepatic lipid metabolism.
Assuntos
Receptor alfa de Estrogênio/metabolismo , Fígado/metabolismo , Reprodução , Adiposidade , Animais , Colesterol/metabolismo , Colágeno/metabolismo , Ciclo Estral , Feminino , Deleção de Genes , Lipoproteínas/metabolismo , Lipoproteínas HDL/metabolismo , Receptores X do Fígado/metabolismo , Camundongos Knockout , PPAR alfa/metabolismo , Ligação Proteica , Transcrição GênicaRESUMO
In female mammals, mechanisms have been developed, throughout evolution, to integrate environmental, nutritional and hormonal cues in order to guarantee reproduction in favorable energetic conditions and to inhibit it in case of food scarcity. This metabolic strategy could be an advantage in nutritionally poor environments, but nowadays is affecting women's health. The unlimited availability of nutrients, in association with reduced energy expenditure, leads to alterations in many metabolic pathways and to impairments in the finely tuned inter-relation between energy metabolism and reproduction, thereby affecting female fertility. Many energetic states could influence female reproductive health being under- and over-weight, obesity and strenuous physical activity are all conditions that alter the profiles of specific hormones, such as insulin and adipokines, thus impairing women fertility. Furthermore, specific classes of nutrients might affect female fertility by acting on particular signaling pathways. Dietary fatty acids, carbohydrates, proteins and food-associated components (such as endocrine disruptors) have per se physiological activities and their unbalanced intake, both in quantitative and qualitative terms, might impair metabolic homeostasis and fertility in premenopausal women. Even though we are far from identifying a "fertility diet", lifestyle and dietary interventions might represent a promising and invaluable strategy to manage infertility in premenopausal women.
Assuntos
Dieta , Metabolismo Energético , Comportamento Alimentar , Fertilidade , Infertilidade Feminina , Estado Nutricional , Reprodução/fisiologia , Feminino , Humanos , Infertilidade Feminina/etiologia , Infertilidade Feminina/prevenção & controleRESUMO
Estrogens play an important role in the regulation of energy homeostasis in female mammals and a reduced ovarian function, due to natural aging or surgery, is associated with body weight increase and fat redistribution. This disruption of energy homeostasis may constitute a trigger for several pathologies known to be associated with climacterium; however, so far, limited attention has been devoted to the ability of estrogen replacement therapies (ERT) to reinstate the balanced energy metabolism characteristic of cycling female mammals. The purpose of the present study was to compare the efficacy of selected ERTs in reversing the ovariectomy-induced gain in body weight. To this aim female ERE-Luc mice were ovariectomized and, after 3 weeks, treated per os for 21 days with: conjugated estrogens, two selective estrogen receptor modulators (bazedoxifene and raloxifene), and the combination of bazedoxifene plus conjugated estrogens (tissue-selective estrogen complex, TSEC). The study shows that the therapy based on TSEC was the most efficacious in reducing the body weight accrued by ovariectomy (OVX). In addition, by means of in vivo imaging, the TSEC treatment was shown to increase estrogen receptor (ER) transcriptional activity selectively in the arcuate nucleus, which is a key area for the control of energy homeostasis. Finally, quantitative analysis of the mRNAs encoding orexigenic and anorexigenic peptides indicated that following ERT with TSEC there was a significant change in Agrp, NPY, and Kiss-1 mRNA accumulation in the whole hypothalamus. Considering that prior studies showed that ERT with TSEC was able to mimic the rhythm of ER oscillatory activity during the reproductive cycle and that such fluctuations were relevant for energy metabolism, the present observations further point to the ER tetradian oscillation as an important component of the ER signaling necessary for the full hormone action and therefore for an efficacious ERT.
Assuntos
Metabolismo Energético/efeitos dos fármacos , Terapia de Reposição de Estrogênios , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Indóis/farmacologia , Cloridrato de Raloxifeno/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Moduladores de Receptor Estrogênico/farmacologia , Estrogênios/farmacologia , Feminino , CamundongosRESUMO
In female animals, energy metabolism and fertility are tightly connected, and reciprocally regulated. However, the relative contributions of metabolic and reproductive pathways have changed over the course of evolution. In oviparous animals, metabolic factors take precedence over fertility, enabling egg production to be inhibited in a nutritionally poor environment. By contrast, in placental mammals, the opposite occurs: the need to feed a developing embryo and neonate forces metabolic pathways to adapt to these reproductive needs. This physiological necessity explains why in female mammals alterations of gonadal activity, including age-dependent cessation of ovarian functions, are associated with a disruption of metabolic homeostasis and consequent inflammatory reactions that trigger the onset of metabolic, cardiovascular, skeletal and neural pathologies. This Review discusses how metabolic homeostasis and reproductive functions interact to optimize female fertility and explains the pathogenic mechanisms underlying the disordered energy metabolism associated with human ovarian dysfunction owing to menopause, polycystic ovary syndrome and Turner syndrome. Finally, this article highlights how hormone replacement therapy might aid the restoration of metabolic homeostasis in women with ovarian dysfunction.
Assuntos
Metabolismo Energético/fisiologia , Fertilidade/fisiologia , Homeostase/fisiologia , Saúde da Mulher , Feminino , Terapia de Reposição Hormonal , Humanos , Ovário/fisiopatologia , Reprodução/fisiologiaRESUMO
Helicobacter pylori (H. pylori) has been found in dental plaque, saliva and lingual sites. To date, taste or olfaction disorders related to H. pylori infections have never been reported. In a review of the literature we found two papers just referring to a sour taste sensation during H. pylori infection. Studies in animal models suggest that changes in taste perception may relate to infections which damage taste buds. We observed an interesting clinical case of a 24-year-old Ghanaian woman with documented H. pylori gastric infection, complaining of cacosmia and cacogeusia. Taste evaluation indicated hypogeusia and highlighted a specific difficulty in discriminating between bitter and acid tastes. Saliva fluid was found positive for the ureA gene (H. pylori ureasi A). On the basis of this report, we hypothesize that taste perception might be correlated with a documented H. pylori infection. So, in a dyspeptic clinical picture in both pre and post diagnostic phase when H. pylori infection is suspected, taste evaluation might be important. Further studies are certainly needed in a large patient population to clarify the possible connection between H. pylori infection and smell-taste distortion.
Assuntos
Gastrite/microbiologia , Infecções por Helicobacter/fisiopatologia , Helicobacter pylori/enzimologia , Percepção Gustatória/fisiologia , 2-Piridinilmetilsulfinilbenzimidazóis , Antibacterianos/uso terapêutico , Claritromicina , Disgeusia/patologia , Feminino , Gastrite/tratamento farmacológico , Gastrite/fisiopatologia , Gastroscopia , Gana/etnologia , Helicobacter pylori/genética , Humanos , Itália , Metronidazol , Transtornos do Olfato/patologia , Pantoprazol , Reação em Cadeia da Polimerase , Saliva/enzimologia , Urease/genética , Adulto JovemRESUMO
We investigated the presence of ß-lactamase genes (bla) in 26 strains of Enterobacteriaceae already found positive for the qnrS1 gene, a plasmid-mediated quinolone resistance determinant. Three strains of K. pneumoniae, isolated in the period 2008-2009 at the University Hospital in Verona, were positive for LAP-2, a narrow-spectrum ß-lactamase. These strains, namely VRB586, VRE185 and VRE196, were cultured from urine, bile and peritoneal drainage, respectively, of different patients from different units. The bla(LAP-2) and qnrS1 resistance determinant genes were separated by ISEcl2 and were located on a 97 kb conjugable and untypable plasmid, which could be transferred to a recipient strain, E. coli J53. The fluoroquinolone and ceftazidime MICs increased 1-2-fold in the transconjugant cells. The three K. pneumoniae strains were found to be clonal by PFGE and were identified as belonging to ST147, an internationally successful clone, by MLST. The plasmid sequence, including ISEcl2 and qnrS1 genes, of K. pneumoniae ST147 was found to be highly similar to previously detected qnrS1-harbouring plasmids, suggesting the plasmid has a stable genetic structure and that these resistance determinants have a common source. To the best of our knowledge, this is the first report of the internationally successful K. pneumoniae ST147 strain carrying bla(LAP-2) and qnrS1 genes and is the first case of LAP ß-lactamase in Italy.
Assuntos
Proteínas de Bactérias/genética , Klebsiella pneumoniae/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Sequência de Bases , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Análise de Sequência de DNARESUMO
A semiautomated, repetitive-sequence-based PCR (rep-PCR) instrument (DiversiLab system) was evaluated in comparison with pulsed-field gel electrophoresis (PFGE) to investigate an outbreak of Serratia marcescens infections in a neonatal intensive care unit (NICU). A selection of 36 epidemiologically related and 8 epidemiologically unrelated isolates was analyzed. Among the epidemiologically related isolates, PFGE identified five genetically unrelated patterns. Thirty-two isolates from patients and wet nurses showed the same PFGE profile (pattern A). Genetically unrelated PFGE patterns were found in one patient (pattern B), in two wet nurses (patterns C and D), and in an environmental isolate from the NICU (pattern G). Rep-PCR identified seven different patterns, three of which included the 32 isolates of PFGE type A. One or two band differences in isolates of these three types allowed isolates to be categorized as similar and included in a unique cluster. Isolates of different PFGE types were also of unrelated rep-PCR types. All of the epidemiologically unrelated isolates were of different PFGE and rep-PCR types. The level of discrimination exhibited by rep-PCR with the DiversiLab system allowed us to conclude that this method was able to identify genetic similarity in a spatio-temporal cluster of S. marcescens isolates.
Assuntos
Técnicas de Tipagem Bacteriana/métodos , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Eletroforese em Gel de Campo Pulsado/métodos , Reação em Cadeia da Polimerase/métodos , Infecções por Serratia/epidemiologia , Serratia marcescens/classificação , Adulto , Automação/métodos , Análise por Conglomerados , Infecção Hospitalar/microbiologia , DNA Bacteriano/genética , Microbiologia Ambiental , Genótipo , Mãos/microbiologia , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Itália/epidemiologia , Epidemiologia Molecular , Enfermeiras e Enfermeiros , Sequências Repetitivas de Ácido Nucleico , Infecções por Serratia/microbiologia , Serratia marcescens/genética , Serratia marcescens/isolamento & purificaçãoAssuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Bacteroides fragilis/efeitos dos fármacos , Bacteroides fragilis/genética , Elementos de DNA Transponíveis , Farmacorresistência Bacteriana , Imipenem/farmacologia , beta-Lactamases/genética , Idoso , Infecções por Bacteroides/microbiologia , Bacteroides fragilis/isolamento & purificação , DNA Bacteriano/química , DNA Bacteriano/genética , Feminino , Humanos , Itália , Dados de Sequência Molecular , Análise de Sequência de DNARESUMO
A total of 78 isolates of Pseudomonas aeruginosa grouped according to the phenotype for ceftazidime and imipenem susceptibility/resistance were used to assess the accuracy of the Vitek 2 system in antimicrobial susceptibility testing. Comparisons were made with a MIC gradient test for piperacillin-tazobactam, ceftazidime, aztreonam, imipenem, meropenem, gentamicin, and ciprofloxacin. For the total of 546 isolate-antimicrobial combinations tested, the category agreement was 83.6%, with 2.0, 1.6, and 12.8% very major, major, and minor errors, respectively. Vitek 2 accuracy was influenced differently by the mechanism responsible for resistance, and interpretation of the results in relation to phenotype could improve the performance of the system.
Assuntos
Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana/métodos , Pseudomonas aeruginosa/efeitos dos fármacos , Kit de Reagentes para Diagnóstico , Resistência beta-Lactâmica , Ceftazidima/farmacologia , Humanos , Imipenem/farmacologia , Fenótipo , Pseudomonas aeruginosa/isolamento & purificação , Reprodutibilidade dos Testes , beta-Lactamas/farmacologiaRESUMO
Cerebrospinal fluid specimens from 226 patients with suspected viral infections of the central nervous system (CNS) were tested by polymerase chain reaction (PCR) to identify the most frequent viruses involved in these infections. A positive PCR result was obtained in 18 patients (7 cases positive for herpes simplex viruses, 5 for enterovirus, 3 for JC virus, 2 for varicella-zoster virus, and 1 for Epstein-Barr virus). All patients with positive PCR results had a definite diagnosis of CNS viral infection. However, a negative result did not rule out the possibility of viral infection of the CNS.
Assuntos
Viroses do Sistema Nervoso Central/líquido cefalorraquidiano , Viroses do Sistema Nervoso Central/diagnóstico , Sistema Nervoso Central/virologia , Adolescente , Adulto , Idoso , Viroses do Sistema Nervoso Central/virologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estudos Prospectivos , Adulto JovemRESUMO
Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used to investigate the genetic relatedness of a total of 41 Enterococcus faecium isolates from different backgrounds (hospital outbreaks, n = 9; documented sporadic infections, n = 10; asymptomatic sporadic carriage of hospitalized patients, n = 9; healthy persons, n = 3; non-human sources, n = 10) over the period 1996-2004 in comparison with clones that have spread in Italy since 1993. Thirty six isolates were vancomycin-resistant and five were vancomycin-susceptible. eBURST analysis of MLST sequence types generated two groups: (1) group 1 (27 isolates) forming a clonal complex (CC17) with the predicted founder corresponding to ST17, a genotype identified in 1994, that included esp-positive and -negative clones isolated from hospitalized patients; and (2) group 2 (14 isolates) including esp-negative clones from different sources (hospitalized patients, healthy persons and non-human sources). The hyl gene was found in five strains with different PFGE types, all belonging to group 1, whereas cylA, gelE, and asa1, were not detected in any of the isolates. Our data showed that the evolution of the MLST C1 epidemic lineage has been continuing in several Italian areas and generating new clones with different PFGE patterns. The main, though not the sole, mechanism that has driven this evolution was confirmed to be linked to the presence of the esp gene.
Assuntos
Surtos de Doenças , Farmacorresistência Bacteriana/genética , Enterococcus faecium/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Resistência a Vancomicina/genética , Fatores de Virulência/genética , Acetamidas/farmacologia , Animais , Anti-Infecciosos/farmacologia , DNA Bacteriano , Eletroforese em Gel de Campo Pulsado , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/isolamento & purificação , Genótipo , Infecções por Bactérias Gram-Positivas/epidemiologia , Humanos , Itália/epidemiologia , Linezolida , Oxazolidinonas/farmacologia , Filogenia , Análise de Sequência de DNARESUMO
A relatively high rate of vancomycin-resistant Enterococcus faecium not susceptible to linezolid was observed in intensive care unit patients. Linezolid-resistant isolates carried the G2576T mutation in the 23S rRNA gene, belonged to different clones, and shared the same allelic profile, which clusters in the C1 multilocus sequence typing epidemic lineage.
Assuntos
Acetamidas/farmacologia , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Oxazolidinonas/farmacologia , Alelos , Sequência de Bases , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , DNA Bacteriano/genética , Surtos de Doenças , Farmacorresistência Bacteriana/genética , Enterococcus faecium/classificação , Enterococcus faecium/isolamento & purificação , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Unidades de Terapia Intensiva , Itália/epidemiologia , Linezolida , Epidemiologia Molecular , RNA Bacteriano/genética , RNA Ribossômico 23S/genética , Resistência a Vancomicina/genéticaRESUMO
We described the first case, to the best of our knowledge, of cutaneous abscess due to Eubacterium lentum in a parenteral drug user, after complete fracture of the right femor. The case underlines the importance of carefully performed microbiological tests, due to the peculiar cultural needs of the micro-organism.
Assuntos
Abscesso/microbiologia , Eubacterium , Fraturas do Fêmur/complicações , Infecções por Bactérias Gram-Positivas/microbiologia , Dermatopatias Bacterianas/microbiologia , Abscesso/diagnóstico , Abscesso/tratamento farmacológico , Adulto , Antibacterianos/uso terapêutico , Eubacterium/isolamento & purificação , Infecções por Bactérias Gram-Positivas/diagnóstico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Imipenem/uso terapêutico , Masculino , Dermatopatias Bacterianas/diagnóstico , Dermatopatias Bacterianas/tratamento farmacológico , Abuso de Substâncias por Via Intravenosa , Resultado do TratamentoRESUMO
Three epidemiologically independent Pseudomonas aeruginosa isolates, representative of the first VIM-1 metallo-beta-lactamase producers detected at three different hospitals in northern Italy, were investigated to determine their genomic relatedness and to compare the structures of the genetic supports for the VIM-1 determinants. The three isolates, all of serotype O11, appeared to be clonally related according to the results of genotyping by macrorestriction analysis of genomic DNA by pulsed-field gel electrophoresis and random amplification of polymorphic DNA. Investigation of the genetic support for the bla(VIM-1) determinant revealed that it was carried on identical or almost identical integrons (named In70.2 and In70.3) located within a conserved genomic context. The integrons were structurally related to In70 and In110, two plasmid-borne bla(VIM-1)-containing integrons from Achromobacter xylosoxidans and Pseudomonas putida isolates, respectively, from the same geographic area (northern Italy) and were found to be inserted close to the res site of a Tn5051-like transposon, different from any of those described previously, that was apparently carried on the bacterial chromosome. The present findings suggest that the three VIM-1-producing isolates are members of the same clonal complex which have been spreading in hospitals in northern Italy since the late 1990s and point to a common ancestry of their bla(VIM-1)-containing integrons.
Assuntos
Sequência Conservada , Hospitais Universitários , Integrons/genética , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/genética , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Sequência de Bases , Eletroforese em Gel de Campo Pulsado , Humanos , Itália/epidemiologia , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/enzimologia , Análise de Sequência de DNA , beta-Lactamases/genéticaRESUMO
Multilocus sequence typing (MLST) was used to obtain insights into the genetic relationships between 14 vancomycin-resistant Enterococcus faecium (VREF) isolates from humans (hospitalized patients, 5 strains) and nonhuman sources (meat and poultry, 9 strains) in northern Italy over the period 1993-2001. The typing scheme (Homan et al., 2002, J. Clin. Microb., 40:1963-1971) based on seven housekeeping genes--adk (adenylate kinase), atpA (ATP synthase, alpha subunit), ddl (D-alanine-D-alanine ligase), gyd (glyceraldehyde-3-phosphate dehydrogenase), gdh (glucose-6-phosphate dehydrogenase), purK (phosphoribosylaminoimidazole carboxylase ATPase subunit), and pstS (phosphate ATP-binding cassette transporter)--was used. In the 14 VREF analyzed, the number of unique alleles ranged from 1 (gyd) to 8 (atpA). Isolates from hospitalized patients were defined by the unique allele purK 1. Nine sequence types (STs) were identified. All of the epidemic strains isolated over the period 2000-2001 showed identical or closely related pulsed-field gel electrophoresis (PFGE) patterns and clustered in the same ST78. These strains shared six of the seven alleles with the strain CA20 representative of the 1993-1999 outbreaks, which PFGE indicated as being unrelated to those of the recent outbreaks. MLST confirmed the unrelatedness of human and nonhuman strains already detected by PFGE. All isolates clustered in three main genetic lineages: group A comprised two of the three isolates from meat; group C the human strains of all outbreaks and one poultry strain; and group B four of the five poultry strains and one meat strain. All human strains carried the esp gene and clustered in the C1 sublineage that has been described as having emerged recently worldwide.
Assuntos
Enterococcus faecium , Infecções por Bactérias Gram-Positivas/epidemiologia , Polimorfismo Genético/genética , Vancomicina/farmacologia , Alelos , Animais , Sequência de Bases , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Surtos de Doenças , Farmacorresistência Bacteriana , Eletroforese em Gel de Campo Pulsado , Enterococcus faecium/classificação , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Microbiologia de Alimentos , Humanos , Itália/epidemiologia , Carne/microbiologia , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Aves Domésticas/microbiologia , Sorotipagem , Fatores de TempoAssuntos
Proteínas de Bactérias , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/enzimologia , beta-Lactamases/análise , beta-Lactamases/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Dados de Sequência Molecular , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , TurquiaRESUMO
We report on the first isolation of an extended-spectrum beta-lactamase-producing Leclercia adecarboxylata strain from the bloodstream in a 58-year-old man with acute myeloid leukemia. The strain, resistant to ceftazidime, cefotaxime, and aztreonam, produces the SHV-12 beta-lactamase, one of the most common variants found in Italian nosocomial isolates of Enterobacteriaceae.
Assuntos
Sangue/microbiologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/isolamento & purificação , Leucemia Mieloide/complicações , Resistência beta-Lactâmica , beta-Lactamases/metabolismo , Doença Aguda , Antibacterianos/farmacologia , Aztreonam/farmacologia , Bacteriemia/microbiologia , Ceftazidima/farmacologia , Meios de Cultura , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Humanos , Leucemia Mieloide/microbiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-IdadeRESUMO
Seven Klebsiella pneumoniae and four Klebsiella oxytoca clinical isolates with different levels of resistance to ciprofloxacin were studied. Mutations in the topoisomerase genes were found in almost all strains, but the contribution of a multidrug efflux system homologous to AcrAB in Escherichia coli was also observed. Overexpression of this efflux system was demonstrated by immunoblotting with antibodies against E. coli AcrA.
Assuntos
Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Klebsiella oxytoca/genética , Klebsiella pneumoniae/genética , Ciprofloxacina/metabolismo , Ciprofloxacina/farmacologia , DNA Topoisomerases Tipo I/genética , Klebsiella oxytoca/efeitos dos fármacos , Klebsiella oxytoca/metabolismo , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/metabolismo , Testes de Sensibilidade MicrobianaRESUMO
A study was conducted to evaluate the new VITEK 2 system (bioMérieux) for identification and antibiotic susceptibility testing of gram-positive cocci. Clinical isolates of Staphylococcus aureus (n = 100), coagulase-negative staphylococci (CNS) (n = 100), Enterococcus spp. (n = 89), Streptococcus agalactiae (n = 29), and Streptococcus pneumoniae (n = 66) were examined with the ID-GPC identification card and with the AST-P515 (for staphylococci), AST-P516 (for enterococci and S. agalactiae) and AST-P506 (for pneumococci) susceptibility cards. The identification comparison methods were the API Staph for staphylococci and the API 20 Strep for streptococci and enterococci; for antimicrobial susceptibility testing, the agar dilution method according to the procedure of the National Committee for Clinical Laboratory Standards (NCCLS) was used. The VITEK 2 system correctly identified to the species level (only one choice or after simple supplementary tests) 99% of S. aureus, 96.5% of S. agalactiae, 96.9% of S. pneumoniae, 92.7% of Enterococcus faecalis, 91.3% of Staphylococcus haemolyticus, and 88% of Staphylococcus epidermidis but was least able to identify Enterococcus faecium (71.4% correct). More than 90% of gram-positive cocci were identified within 3 h. According to the NCCLS breakpoints, antimicrobial susceptibility testing with the VITEK 2 system gave 96% correct category agreement, 0.82% very major errors, 0.17% major errors, and 2.7% minor errors. Antimicrobial susceptibility testing showed category agreement from 94 to 100% for S. aureus, from 90 to 100% for CNS, from 91 to 100% for enterococci, from 96 to 100% for S. agalactiae, and from 91 to 100% for S. pneumoniae. Microorganism-antibiotic combinations that gave very major errors were CNS-erythromycin, CNS-oxacillin, enterococci-teicoplanin, and enterococci-high-concentration gentamicin. Major errors were observed for CNS-oxacillin and S. agalactiae-tetracycline combinations. In conclusion the results of this study indicate that the VITEK 2 system represents an accurate and acceptable means for performing identification and antibiotic susceptibility tests with medically relevant gram-positive cocci.