Virulence and Resistance Determinants of Uropathogenic Escherichia coli Strains Isolated from Pregnant and Non-Pregnant Women from Two States in Mexico

Manuel G Ballesteros-Monrreal; Margarita Mp Arenas-Hernández; Yessica Enciso-Martínez; Claudia F Martínez-de la Peña; Rosa Del C Rocha-Gracia; Patricia Lozano-Zaraín; Armando Navarro-Ocaña; Ygnacio Martínez-Laguna; Rafael de la Rosa-López

doi:10.2147/IDR.S226215

Virulence and Resistance Determinants of Uropathogenic Escherichia coli Strains Isolated from Pregnant and Non-Pregnant Women from Two States in Mexico

Infect Drug Resist. 2020 Jan 30:13:295-310. doi: 10.2147/IDR.S226215. eCollection 2020.

Authors

Manuel G Ballesteros-Monrreal¹, Margarita Mp Arenas-Hernández¹, Yessica Enciso-Martínez², Claudia F Martínez-de la Peña¹, Rosa Del C Rocha-Gracia¹, Patricia Lozano-Zaraín¹, Armando Navarro-Ocaña³, Ygnacio Martínez-Laguna¹, Rafael de la Rosa-López²

Affiliations

¹ Posgrado en Microbiología, Centro de Investigación en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria, Puebla, Pue, Mexico.
² Departamento de Ciencias Químico Biológicas y Agropecuarias, Universidad de Sonora Unidad Regional Norte, Caborca, Sonora, Mexico.
³ Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de Mexico, Mexico.

Abstract

Background/purpose: Uropathogenic E. coli (UPEC) is the main cause of urinary tract infection (UTI) and it is known that pregnant women have a higher risk for UTI. UPEC has a variety of virulence and antibiotic resistance factors that facilitate its pathogenic success and it is crucial to know which are the susceptibility patterns, Extended-Spectrum-β-Lactamase (ESBL) production, virulence genes, pathogenicity islands (PAI), phylogenetic groups and serotypes among strains isolated from pregnant and non-pregnant women.

Methods: One hundred fifty UPEC strains were isolated from pregnant and non-pregnant women from two different Mexican states (Sonora and Puebla). Strains were analyzed using the Kirby-Bauer method for the determination of antibiotic susceptibility and ESBL. Virulence genes, PAIs and phylogenetic groups were determined using a multiplex PCR. Strains were serotyped by an agglutination assay. Blood agar and CAS agar were used for phenotypic assays.

Results: 92.7% of UPEC strains showed multidrug-resistant (MDR), 6.7% extremely-resistant (XDR) and 0.6% pandrug-resistant (PDR). The highest resistance was determined to be for β-lactam antibiotics (>72% in both states) and 44.5% of the UPEC strains were ESBL⁺. The predominant virulence genes found were fimH (100%), iucD (85%) and iha (60%). The strains isolated from pregnant women from Puebla presented a large percentage of genes associated with upper urinary tract infections. PAIs were found in 51% and 68% of the strains from Sonora and Puebla, respectively. All the strains were siderophores producers and 41.5% produced hemolysis. The serotypes found were diverse and belonged to phylogroups A, B2 and C.

Conclusion: The UPEC strains from this study are MDR with tendency to XDR or PDR, they can cause upper UTIs and are serotypically and phylogenetically diverse, which supports the need to develop new strategies for UTI treatment in pregnant and non-pregnant Mexican women.

Keywords: UPEC in pregnancy; antibiotic resistance; multiplex PCR; phylogenetic groups; serotype; virulence profile.