Distribution of virulence genes and their association with antimicrobial resistance among uropathogenic Escherichia coli isolates from Iranian patients

Abstract

BackgroundUrinary tract infections (UTIs) are one of the most frequent diseases encountered by humans worldwide. The presence of multidrug-resistant (MDR) uropathogenic Escherichia coli (UPEC) harboring several virulence factors, is a major risk factor for inpatients. We sought to investigate the rate of antibiotic resistance and virulence-associated genes among the UPECs isolated from an Iranian symptomatic population.MethodsA total of 126 isolates from inpatients with UTI from different wards were identified as UPEC using the conventional microbiological tests. After identification of UPECs, all the isolates were subjected to antimicrobial susceptibility test and polymerase chain reaction (PCR) to identify the presence of 9 putative virulence genes and their association with the clinical outcomes or antimicrobial resistance.ResultsThe data showed that the highest and the lowest resistance rates were observed against ampicillin (88.9%), and imipenem (0.8%), respectively. However, the frequency of resistance to ciprofloxacin was found to be 55.6%. High prevalence of MDR (77.8%) and extended-spectrum β-lactamase (ESBL) (54.8%) were substantial. PCR results revealed the frequency of virulence genes ranged from 0 to 99.2%. Among 9 evaluated genes, the frequency of 4 genes (fimH, sfa, iutA, and PAI marker) was > 50% among all the screened isolates. The iutA, pap GII, and hlyA genes were more detected in the urosepsis isolates with significantly different frequencies. The different combinations of virulence genes were characterized as urovirulence patterns. The isolates recovered from pyelonephritis, cystitis, and urosepsis cases revealed 27, 22, and 6 virulence patterns, respectively. A significant difference was determined between ESBL production with pap GII, iutA, and PAI marker genes.ConclusionsOur study highlighted the MDR UPEC with high heterogeneity of urovirulence genes. Considering the high rate of ciprofloxacin resistance, alternative drugs and monitoring of the susceptibility profile for UPECs are recommended.Electronic supplementary materialThe online version of this article (10.1186/s12879-018-3467-0) contains supplementary material, which is available to authorized users.

Characterization of Uropathogenic Escherichia coli: Distribution of Adhesin-Encoding Genes and O-Serotypes Among Ciprofloxacin Susceptible and Resistant Isolates

“…The sfa was the second most predominant adhesin gene (81%) in our isolates that was in agreement with a research carried out in Shiraz (Fars province, Iran) with a frequency of 79.4% (29). In previous reports, the prevalence of the sfa was conversely less than 30% (7).…”

“…In previous reports, the prevalence of the sfa was conversely less than 30% (7). Nevertheless, the exact role of S-fimbriae is not clarified; therefore, the distribution of bacterium within the host tissue depends on this adhesin marker (29). In our isolates, the papC was the third most prevalent adhesin gene (57%) that was similar to a study conducted in Jahrom (Fars province, Iran) (30).…”

“…In addition, 34% of the isolates had papG II that is responsible for encoding PapG adhesion on the tips of P fimbriae. In other studies, it was realized that various classes of PapG adhesion were dominant in the E. coli strains isolated from UTIs (6,29). In the current study, the frequency of papGI and papGIII were 16% and 4%, respectively.…”

Presencia de genes fimH y afa en aislamientos urinarios de Escherichia coli productora de betalactamasas de espectro extendido en Lima, Perú

“…Se concluyó que la concentración óptima de cebadores es 0,1 μM con 0,5 UI de concentración de Taq. Porcentaje cina estaban asociadas significativamente, lo que difiere con lo reportado por Malekzadegan, et al (19) , quienes no encontraron asociación entre el gen afa y la no sensibilidad a la amikacina, pero sí entre la presencia del gen afa y la producción de BLEE.…”

<p>Virulence and Resistance Determinants of Uropathogenic <em>Escherichia coli</em> Strains Isolated from Pregnant and Non-Pregnant Women from Two States in Mexico</p>

“…To date, more than 350-different ESBL have been described and mainly are encoded in plasmids. [26][27][28] Some investigations indicated that depending on enzyme substrate, the strains can be classified as ESBL producers or carbapenemases producers. 29,30 This is important because carbapenems are in the list of last resource antibiotics for treatment.…”