Persistencia de un clon ST6 de Enterococcus faecalis con genotipo vanB2 en dos hospitales de Aragón

espanolIntroduccion Con el objetivo de estudiar la evolucion del brote por Enterococcus faecalis ST6 genotipo vanB2 descrito en 2009-2010 en 3 hospitales de Zaragoza, se caracterizaron todos los aislados clinicos E.faecalis resistentes a vancomicina obtenidos entre 2011 y 2013 en dichos hospitales. Metodos Caracterizacion molecular de los aislados y estudio de su relacion clonal por electroforesis en campos pulsados. Revision de las historias clinicas de los pacientes. Resultados Se detectaron 79 aislados E.faecalis genotipo vanB2 de 73 pacientes de 2 de los 3 hospitales analizados, la mayoria de origen urinario. El 46,5% de los casos fueron nosocomiales. La distribucion segun servicios hospitalarios mostro gran variabilidad, no pudiendose identificar una fuente de infeccion comun. Todas las cepas fueron multirresistentes (vancomicina, eritromicina, tetraciclina, ciprofloxacino, estreptomicina, gentamicina, kanamicina) y pertenecieron al clon ST6. El 93,7% eran indistinguibles al clon del inicio del brote o subtipos estrechamente relacionados. Conclusion El brote se mantiene constante en los 3 anos posteriores a su descripcion, lo que senala la necesidad de mantener un control activo que limite la emergencia y diseminacion de clones resistentes a vancomicina. EnglishIntroduction In order to study the evolution of the outbreak that occurred between 2009 and 2010 in 3 hospitals in Zaragoza, all vancomycin-resistant clinical Enterococcus faecalis isolates identified between 2011 and 2013 at these hospitals were characterised. Methods Molecular characterisation of the isolates and analysis of their clonal relationships was performed using pulsed field electrophoresis, along with a retrospective review of the patient records. Results A total of 79 vancomycin-resistant E.faecalis isolates with genotype vanB2 of 73 patients were recovered in 2 of the 3 hospitals, most of them from urine specimens. About 46% of the cases were nosocomial. Distribution of the isolates among hospital services demonstrated high variability, making it difficult to predict a common source of infection. All the strains were multiresistant (vancomycin, erythromycin, tetracycline, ciprofloxacin, streptomycin, gentamicin, kanamycin) and belonged to lineage ST6. Seventy-four isolates (93.7%) were identical or closely related to the dominant one in the origin of the outbreak. Conclusion The outbreak remains constant over three years after being initially described, indicating the need to implement an active control in order to limit the emergence and spread of vancomycin-resistant clones