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1.
Infect Genet Evol ; 121: 105600, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38692501

ABSTRACT

Urinary tract infections (UTI) caused by uropathogenic Escherichia coli (UPEC) pose a global health concern. Resistance mechanisms, including genetic mutations in antimicrobial target genes, efflux pumps, and drug deactivating enzymes, hinder clinical treatment. These resistance factors often spread through mobile genetic elements. Molecular techniques like whole genome sequencing (WGS), multilocus sequence typing (MLST), and phylotyping help decode bacterial genomes and categorise resistance genes. In this study, we analysed 57 UPEC isolates from different UTI patients following EUCAST guidelines. A selection of 17 representative strains underwent WGS, phylotyping, MLST, and comparative analysis to connect laboratory susceptibility data with predictive genomics based on key resistance genes and chromosomal mutations in antimicrobial targets. Trimethoprim resistance consistently correlated with dfr genes, with six different alleles detected among the isolates. These dfr genes often coexisted with class 1 integrons, with the most common gene cassette combining dfr and aadA. Furthermore, 52.9% of isolates harboured the blaTem-1 gene, rendering resistance to ampicillin and amoxicillin. Ciprofloxacin-resistant strains exhibited mutations in GyrA, GyrB and ParC, plasmid-mediated quinolone resistance genes (qnrb10), and aac(6')-Ib-cr5. Nitrofurantoin resistance in one isolate stemmed from a four amino acid deletion in NfsB. These findings illustrate the varied strategies employed by UPEC to resist antibiotics and the correlation between clinical susceptibility testing and molecular determinants. As molecular testing gains prominence in clinical applications, understanding key resistance determinants becomes crucial for accurate susceptibility testing and guiding effective antimicrobial therapy.


Subject(s)
Anti-Bacterial Agents , Escherichia coli Infections , Microbial Sensitivity Tests , Urinary Tract Infections , Uropathogenic Escherichia coli , Whole Genome Sequencing , Uropathogenic Escherichia coli/genetics , Uropathogenic Escherichia coli/drug effects , Humans , Whole Genome Sequencing/methods , Escherichia coli Infections/microbiology , Anti-Bacterial Agents/pharmacology , Urinary Tract Infections/microbiology , Ireland , Genome, Bacterial , Drug Resistance, Bacterial/genetics , Phylogeny , Phenotype , Multilocus Sequence Typing , Female , Male
2.
Microorganisms ; 11(9)2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37764013

ABSTRACT

Urinary tract infections (UTIs) are among the most common bacterial infections, especially among women and older adults, leading to a significant global healthcare cost burden. Uropathogenic Escherichia coli (UPEC) are the most common cause and accounts for the majority of community-acquired UTIs. Infection by UPEC can cause discomfort, polyuria, and fever. More serious clinical consequences can result in urosepsis, kidney damage, and death. UPEC is a highly adaptive pathogen which presents significant treatment challenges rooted in a complex interplay of molecular factors that allow UPEC to evade host defences, persist within the urinary tract, and resist antibiotic therapy. This review discusses these factors, which include the key genes responsible for adhesion, toxin production, and iron acquisition. Additionally, it addresses antibiotic resistance mechanisms, including chromosomal gene mutations, antibiotic deactivating enzymes, drug efflux, and the role of mobile genetic elements in their dissemination. Furthermore, we provide a forward-looking analysis of emerging alternative therapies, such as phage therapy, nano-formulations, and interventions based on nanomaterials, as well as vaccines and strategies for immunomodulation. This review underscores the continued need for research into the molecular basis of pathogenesis and antimicrobial resistance in the treatment of UPEC, as well as the need for clinically guided treatment of UTIs, particularly in light of the rapid spread of multidrug resistance.

3.
Med Sci (Basel) ; 11(1)2022 12 20.
Article in English | MEDLINE | ID: mdl-36649038

ABSTRACT

The purpose of this study was to determine the effect of sublethal concentrations of nitrofurantoin, ciprofloxacin, and trimethoprim on biofilm formation in 57 uropathogenic Escherichia coli strains (UPEC). The minimum inhibitory concentration of nitrofurantoin, ciprofloxacin, and trimethoprim was determined and the biofilm formation for each isolate with and without sub-lethal concentrations of each antibiotic was then quantified. The statistical significance of changes in biofilm formation was ascertained by way of a Dunnett's test. A total of 22.8% of strains were induced to form stronger biofilms by nitrofurantoin, 12% by ciprofloxacin, and 19% by trimethoprim; conversely 36.8% of strains had inhibited biofilm formation with nitrofurantoin, 52.6% with ciprofloxacin, and 38.5% with trimethoprim. A key finding was that even in cases where the isolate was resistant to an antibiotic as defined by EUCAST, many were induced to form a stronger biofilm when grown with sub-MIC concentrations of antibiotics, especially trimethoprim, where six of the 22 trimethoprim resistant strains were induced to form stronger biofilms. These findings suggest that the use of empirical treatment with trimethoprim without first establishing susceptibility may in fact potentiate infection in cases where a patient who is suffering from a urinary tract infection (UTI) caused by trimethoprim resistant UPEC is administered trimethoprim. This emphasizes the need for laboratory-guided treatment of UTI.


Subject(s)
Urinary Tract Infections , Uropathogenic Escherichia coli , Humans , Nitrofurantoin/pharmacology , Ciprofloxacin/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Urinary Tract Infections/drug therapy , Trimethoprim, Sulfamethoxazole Drug Combination/pharmacology , Biofilms
4.
Med Sci (Basel) ; 9(2)2021 05 25.
Article in English | MEDLINE | ID: mdl-34070530

ABSTRACT

SARS-CoV-2 infection has generated the biggest pandemic since the influenza outbreak of 1918-1919. One clear difference between these pandemics has been the ability to test for the presence of the virus or for evidence of infection. This review examined the performance characteristics of sample types via PCR detection of the virus, of antibody testing, of rapid viral antigen detection kits and computerised tomography (CT) scanning. It was found that combined detection approaches, such as the incorporation of CT scans, may reduce the levels of false negatives obtained by PCR detection in both symptomatic and asymptomatic patients, while sputum and oral throat washing sample types should take precedence over swabbing when available. Rt-PCR assays for detection of the virus remain the gold-standard method for SARS-CoV-2 diagnosis and can be used effectively on pooled samples for widespread screening. The novel Oxford antibody assay was found to have the highest sensitivity and specificity of four currently available commercial antibody kits but should only be used during a specific timeframe post-symptom onset. Further research into transmission modes between symptomatic and asymptomatic patients is needed. Analysis of the performance characteristics of different sampling and detection methods for SARS-CoV-2 showed that timing of sampling and testing methods used can greatly influence the rate of false-positive and false-negative test results, thereby influencing viral spread.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , Diagnostic Errors , Specimen Handling/methods , Asymptomatic Infections , COVID-19 Nucleic Acid Testing , COVID-19 Serological Testing , Humans , Real-Time Polymerase Chain Reaction , Tomography, X-Ray Computed
5.
Diseases ; 8(2)2020 Apr 30.
Article in English | MEDLINE | ID: mdl-32365789

ABSTRACT

Antibiotic resistance is increasing to an extent where efficacy is not guaranteed when treating infection. Biofilm formation has been shown to complicate treatment, whereby the formation of biofilm is associated with higher minimum inhibitory concentration values of antibiotic. The objective of the current paper was to determine whether biofilm formation is variable among uropathogenic Escherichia coli isolates and whether formation is associated with recurrent urinary tract infection (UTI), and whether it can be predicted by phenotypic appearance on culture medium A total of 62 E. coli isolates that were reported as the causative agent of UTI were studied (33 from patients denoted as having recurrent UTI and 29 from patients not specified as having recurrent UTI). The biofilm forming capability was determined using a standard microtitre plate method, using E. coli ATCC 25922 as the positive control. The majority of isolates (93.6%) were found to be biofilm formers, whereby 81% were denoted as strong or very strong producers of biofilm when compared to the positive control. Through the use of a Wilcox test, the difference in biofilm forming propensity between the two patient populations was found to not be statistically significant (p = 0.5). Furthermore, it was noted that colony morphology was not a reliable predictor of biofilm-forming propensity. The findings of this study indicate that biofilm formation is very common among uropathogens, and they suggest that the biofilm-forming capability might be considered when treating UTI. Clinical details indicating a recurrent infection were not predictors of biofilm formation.

6.
J Agromedicine ; 14(2): 157-63, 2009.
Article in English | MEDLINE | ID: mdl-19437272

ABSTRACT

Farmers operate within hazardous environments while conducting their day-to-day tasks, potentially resulting in injury or disability. Disability can serve as a major life-changing event for the farmer, the farm family, and the farm business. In Ireland, the agricultural sector reported the highest incidence of disability, yet there is relatively little known on the impact of agricultural-based disability. In 2007, a questionnaire was appended to the Teagasc (Irish Agricultural and Food Development Authority) National Farm Survey to obtain some metric of the prevalence and impact of disability on Irish farms, in addition to quantifying service/support requirements of farm operators experiencing disability. Almost 5.9% (approximately 6611) of Irish farm operators reported disability, primarily caused through illness/disease. Arthritis (31.4%), back problems (17%), and heart circulatory problems (12.5%) were most frequently reported. The lowest prevalence of disability was found among tillage (1.4%) and dairy (4.1%) farms, with the highest prevalence among cattle farms (7.1%). Family farm income was lower on disability-experiencing farms relative to nondisability farms (123 euros per hectare), with a lower participation in off-farm employment also identified. Many farm operators (approximately 20%) ceased off-farm employment following disability. Discontinuation of off-farm employment can further precipitate family farm income decline, but also place additional pressures on the farm business if quality services/supports are not available. The current provision of services/supports to farm operators experiencing disability is perceived largely insufficient across the entire service/support spectrum from when disability was first experienced through to retirement. Awareness and issues surrounding eligibility were the primary reasons for failing to avail of currently available service/supports.


Subject(s)
Agricultural Workers' Diseases/epidemiology , Agriculture/statistics & numerical data , Disabled Persons/statistics & numerical data , Accidents, Occupational/statistics & numerical data , Adult , Aged , Aged, 80 and over , Agriculture/classification , Agriculture/economics , Female , Health Services Needs and Demand , Humans , Ireland/epidemiology , Male , Middle Aged , Rural Health Services , Surveys and Questionnaires , Young Adult
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