Relación entre factores de virulencia, resistencia a antibióticos y los grupos filogenéticos de Escherichia coli uropatógena en dos localidades de México / Relationship between virulence factors, resistance to antibiotics and phylogenetic groups of uropathogenic Escherichia coli in two locations in Mexico

Introducción: Escherichia coli es el principal agente causal de infecciones del tracto urinario (ITU), y sus factores de virulencia son los responsables de la gravedad de estas infecciones emergentes. El objetivo de este estudio fue evaluar la relación entre los determinantes de virulencia y susceptibilidad a antibióticos con los grupos filogenéticos de E.coli aisladas de ITU en 2 localidades de México. Métodos: Se analizaron 50 aislamientos de E.coli de una localidad en el centro del país y 57 provenientes de una localidad al suroeste. Los aislamientos fueron caracterizados fenotípica (serotipificación, ensayos de adherencia, formación de biopelícula, producción de hemolisina y susceptibilidad antibióticos) y genotípicamente (grupos filogenéticos y genes de virulencia). Resultados: Los grupos filogenéticos B2 (60%) y F (12%) fueron significativamente predominantes en la localidad del centro con mayor frecuencia de los genes fimH (96%), iutA (66%) y sat (36%) en comparación con la localidad en el suroeste, donde los grupos A (35%) y B1 (21%) fueron más frecuentes y presentaron menor cantidad de genes de virulencia. El 21,5% del total de aislamientos pertenecieron al grupo O25-ST131. La producción de hemolisina y biopelícula fue significativamente mayor en cepas de la localidad del sureste. La resistencia a ampicilina (92,5%), tetraciclina (76,6%) y trimetoprim/sulfametoxazol (70,1%) fueron las más comunes en ambos grupos. Conclusión: El grupo filogenético, los factores de virulencia y la susceptibilidad a antibióticas de E.colicausante de ITU en la comunidad varían significativamente entre las poblaciones mexicanas estudiadas. Los grupos filogenéticos A y B1 pueden ser multirresistentes y tienen la capacidad de producir infecciones urinarias (AU)

Introduction: Escherichia coli is the major causative agent of urinary tract infections (UTI), and virulence factors are responsible for the severity of these emerging infections. The aim of this study was to evaluate the relationship between virulence determinants and antibiotic susceptibility with phylogenetic groups of E.coli isolates of UTI in two locations in Mexico. Methods: An analysis was performed on 50 isolates of E.coli from the centre of the country and 57 from a town in the southwest. The isolates were characterized by phenotype (serotyping assays, in vitro adhesion, biofilm formation, production of haemolysin, and antibiotic susceptibility) and genotype (phylogenetic groups and virulence genes). Results: In the centre of the country location the phylogenetic group B2 (60%) and F (12%) were significantly more prevalent and had a higher frequency of genes, fimH (96%), iutA (66%), sat(36%), compared to the southwest location, where the group A (35%) and B1 (21%) were significantly predominant and had fewer virulence genes. About one-fifth (21.5%) of all isolates belonged to the O25-ST131 group. Haemolysin and biofilm producing strains were significantly higher in the southwest location. Resistance to ampicillin (92.5%), tetracycline (76.6%), and trimethoprim/sulfamethoxazole (70.1%) were the most common in both groups. Conclusion: The phylogenetic group, virulence factors, and antibiotic susceptibility of the E.coli that causes UTI in the community, varies significantly among the Mexican populations studied. Phylogenetic groups A and B1 may be multidrug resistant and have the ability to produce UTI (AU)

Relationship between virulence factors, resistance to antibiotics and phylogenetic groups of uropathogenic Escherichia coli in two locations in Mexico. / Relación entre factores de virulencia, resistencia a antibióticos y los grupos filogenéticos de Escherichia coli uropatógena en dos localidades de México.

INTRODUCTION: Escherichia coli is the major causative agent of urinary tract infections (UTI), and virulence factors are responsible for the severity of these emerging infections. The aim of this study was to evaluate the relationship between virulence determinants and antibiotic susceptibility with phylogenetic groups of E.coli isolates of UTI in two locations in Mexico. METHODS: An analysis was performed on 50 isolates of E.coli from the centre of the country and 57 from a town in the southwest. The isolates were characterized by phenotype (serotyping assays, in vitro adhesion, biofilm formation, production of haemolysin, and antibiotic susceptibility) and genotype (phylogenetic groups and virulence genes). RESULTS: In the centre of the country location the phylogenetic group B2 (60%) and F (12%) were significantly more prevalent and had a higher frequency of genes, fimH (96%), iutA (66%), sat (36%), compared to the southwest location, where the group A (35%) and B1 (21%) were significantly predominant and had fewer virulence genes. About one-fifth (21.5%) of all isolates belonged to the O25-ST131 group. Haemolysin and biofilm producing strains were significantly higher in the southwest location. Resistance to ampicillin (92.5%), tetracycline (76.6%), and trimethoprim/sulfamethoxazole (70.1%) were the most common in both groups. CONCLUSION: The phylogenetic group, virulence factors, and antibiotic susceptibility of the E.coli that causes UTI in the community, varies significantly among the Mexican populations studied. Phylogenetic groups A and B1 may be multidrug resistant and have the ability to produce UTI.