IMPAM   23988
INSTITUTO DE INVESTIGACIONES EN MICROBIOLOGIA Y PARASITOLOGIA MEDICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
IDENTIFICATION OF MOBILE GENETIC ELEMENTS ENCODED IN CLINICAL ISOLATES OF UROPATHOGENIC Escherichia coli
Autor/es:
ALEJANDRA RIVOLTA; MICAELA IRUSTA; GISELA PARMECIANO DI NOTO; DANIELA ARCHUBY; LAURA DERDOY; CECILIA QUIROGA
Lugar:
Cordoba
Reunión:
Congreso; XI Congreso Argentino de Microbiología General; 2015
Institución organizadora:
SAMIGE
Resumen:
Escherichia coli is a versatile bacterium that thrives in a wide variety of niches. This microorganism is commensal of the gastrointestinal tract of humans; however some clones can acquire virulence and antimicrobial determinants by way of incorporation of mobile elements into their genome. Uropathogenic E. coli (UPEC) is a pathogenic variant that infects and colonizes the urinary tract. In recent years, it has been observed an increment on the resistance and virulence of UPEC strains as a result of the acquisition of broad-host range (BHR) plasmids and pathogenicity islands. The aim of this work was to evaluate the presence of key mobile elements responsible for the dissemination of antimicrobial resistance and virulence factors in the genome of UPEC isolated from a public hospital from Buenos Aires city. We used twenty-one (n=21) E. coli isolates from urine samples with different antimicrobial susceptibilities; eleven of which were resistant to third and fourth generation of cephalosporins. Detection of BHR plasmids from incompatibility groups IncW, IncP and IncN was done by standard PCR using specific primers. Fifteen out of 21 isolates harbored BHR plasmids, in which the IncP group was the most prevalent element (10/15). Only two isolates harbored two plasmids, both from IncW and IncP groups. Overall, no correlation was observed for the presence of these BHR plasmids and the antimicrobial susceptibility. We also searched for the presence of the pathogenicity island PAI-1, one of the most disseminated PAI in UPEC strains, as well as for class 1 and 2 integrons. We observed that most UPEC isolates from our study code for this PAI (14 out of 21), confirming that this element is also widely spread in our population. In addition, we noticed a co-ocurrence of PAI-1 and the BHR plasmids tested here (7/21). On the other hand, only seven isolates were positive for intI1 whereas no intI2 was detected. Six out of 7 intI1 positive strains were consistent with resistance to third and fourth generation of cephalosporins, which suggests that this platform may contain genes coding for their respective beta-lactamases. Last, only 3 strains positive for intI1 harbored a BHR plasmid, which indicates that the remaining integrons may be located in plasmids from other incompatibility groups or in genomic islands. Our work evidences that the UPEC isolates used in this study acquired preferably plasmids from the IncP incompatibility group and the element PAI-1. We also observed the co-occurrence of mobile elements that could be beneficial for the survival of these pathogens. The presence of BHR plasmids in UPEC isolates reflects the adaptation and evolution of this microorganism that may result in a steady and troublesome increment of multirresistance in the community.