RESUMO
Methicillin resistance in Staphylococcus aureus has rapidly increased over the last two decades. This increase is paralleled by the emergence of unique multi-resistant MRSA clones. In Brazil, Argentina, Uruguay, Portugal and Czech Republic a specific MRSA clone is widely spread, the so-called Brazilian epidemic clone. Another epidemic clone, the Iberian clone, is disseminated in Spain, Portugal, Belgium, Scotland, Italy, Germany and New York. Thus, a large number of hospital-acquired infections have been caused by specific MRSA clones. Using different molecular techniques for MRSA typing, we verified that two unique epidemic clones are spread over large geographic area in the US. In addition, we showed that a previously described MRSA clone type, the New York clone (I::A:A), is widely spread beyond the New York frontiers.
Assuntos
Resistência a Meticilina/genética , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/efeitos dos fármacos , Clonagem Molecular/métodos , Eletroforese em Gel de Campo Pulsado , Humanos , Testes de Sensibilidade Microbiana , Polimorfismo Genético , Infecções Estafilocócicas/sangue , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificação , Estados Unidos/epidemiologiaRESUMO
Staphylococcus aureus isolates (n = 1201) from 20 centers in Europe, the USA and Brazil were evaluated for the presence of epidemiologic markers. Plasmid typing and restriction endonuclease analysis of plasmid DNA confirmed the presence of an apparently identical plasmid in 13% of clinical isolates. The plasmid was recovered from all 20 hospitals studied, with an overall frequency of greater than 10% on each of the three continents. Since relatively few staphylococcal plasmids may be shared by epidemiologically unrelated strains, there are inherent limitations to this otherwise useful technique. Additionally, these data demonstrate the importance of including unrelated strains of Staphylococcus aureus from the local region as controls when molecular typing methods are performed.
Assuntos
DNA Bacteriano/análise , Plasmídeos/genética , Staphylococcus aureus/genética , Brasil , Desoxirribonuclease EcoRI/metabolismo , Desoxirribonuclease HindIII/metabolismo , Europa (Continente) , Testes de Sensibilidade Microbiana , Staphylococcus aureus/classificação , Staphylococcus aureus/efeitos dos fármacos , Estados UnidosRESUMO
An outbreak of watery diarrhea occurred in 14 of 15 infants in a special care unit over a four-day period. Using the CHO cell assay for enterotoxin, we found that 11 of these patients had toxigenic bacteria in their stools. These bacteria comprised nine different serotypes of three species of organisms: Escherichia coli, Klebsiella, and Citrobacter. None of the three serotypes of E. coli were classic enteropathogenic serotypes. Rectal swab specimens from all 15 infants were examined for the presence of viruses by electron microscopic and cell culture techniques as well as by studies in suckling mice. None had parvovirus- or reovirus-like agents and two had adenoviruses. No other viral agents were detected. Of 38 bacterial strains isolated from ten control infants without diarrhea, three Klebsiella strains from two individuals were found to be toxigenic. Analysis of a total of 136 enteric isolates showed that toxigenicity as measured by the CHO assay was strongly associated with strains isolated during acute diarrheal illness when compared with strains isolated in convalescence (p less than 10(-5)) or with strains from control infants without diarrhea (p less than 10(-5)). This study raises the possibility of an outbreak of disease caused by a transmissible plasmid responsible for a cholera-like enterotoxin production in several enteric bacterial strains.