Urinary tract infections: epidemiology, mechanisms of infection and treatment options

Comparison of Superhydrophilic, Liquid-Like, Liquid-Infused, and Superhydrophobic Surfaces in Preventing Catheter-Associated Urinary Tract Infection and Encrustation

Over the past decade, superhydrophilic zwitterionic surfaces, slippery liquid-infused porous surfaces, covalently attached liquid-like surfaces, and superhydrophobic surfaces have emerged as the most promising strategies to prevent biofouling on biomedical devices. Despite working through different mechanisms, they have demonstrated superior efficacy in preventing the adhesion of biomolecules (e.g., proteins and bacteria) compared with conventional material surfaces. However, their potential in combating catheter-associated urinary tract infection (CAUTI) remains uncertain. In this research, we present the fabrication of these four coatings for urinary catheters and conduct a comparative assessment of their antifouling properties through a stepwise approach. Notably, the superhydrophilic zwitterionic coating demonstrated the highest antifouling activity, reducing 72.3% of fibrinogen deposition and over 75% of bacterial adhesion (Escherichia coli and Staphylococcus aureus) when compared with an uncoated polyvinyl chloride (PVC) surface. The zwitterionic coating also exhibited robust repellence against blood and improved surface lubricity, decreasing the dynamic coefficient of friction from 0.63 to 0.35 as compared with the PVC surface. Despite the fact that the superhydrophilic zwitterionic and hydrophobic liquid-like surfaces showed great promise in retarding crystalline biofilm formation in the presence of Proteus mirabilis, it is worth noting that their long-term antifouling efficacy may be compromised by the proliferation and migration of colonized bacteria as they are unable to kill them or inhibit their swarming. These findings underscore both the potential and limitations of these ultralow fouling materials as urinary catheter coatings for preventing CAUTI.

Fabrication of levofloxacin-loaded porcine acellular dermal matrix hydrogel and functional assessment in urinary tract infection

Bacterial cystitis, a commonly occurring urinary tract infection (UTI), is renowned for its extensive prevalence and tendency to recur. Despite the extensive utilization of levofloxacin as a conventional therapeutic approach for bacterial cystitis, its effectiveness is impeded by adverse toxic effects, drug resistance concerns, and its influence on the gut microbiota. This study introduces Lev@PADM, a hydrogel with antibacterial properties that demonstrates efficacy in the treatment of bacterial cystitis. Lev@PADM is produced by combining levofloxacin with decellularized porcine acellular dermal matrix hydrogel and exhibits remarkable biocompatibility. Lev@PADM demonstrates excellent stability as a hydrogel at body temperature, enabling direct administration to the site of infection through intravesical injection. This localized delivery route circumvents the systemic circulation of levofloxacin, resulting in a swift and substantial elevation of the antimicrobial agent's concentration specifically at the site of infection. The in vivo experimental findings provide evidence that Lev@PADM effectively prolongs the duration of levofloxacin's action, impedes the retention and invasion of E.coli in the urinary tract, diminishes the infiltration of innate immune cells into infected tissues, and simultaneously preserves the composition of the intestinal microbiota. These results indicate that, in comparison to the exclusive administration of levofloxacin, Lev@PADM offers notable benefits in terms of preserving the integrity of the bladder epithelial barrier and suppressing the recurrence of urinary tract infections.

Multispecies bacterial invasion of human host cells

Urinary tract infection (UTI), one of the most common bacterial infections worldwide, is a typical example of an infection that is often polymicrobial in nature. While the overall infection course is known on a macroscale, bacterial behavior is not fully understood at the cellular level and bacterial pathophysiology during multispecies infection is not well characterized. Here, using clinically relevant bacteria, human epithelial bladder cells and human urine, we establish co-infection models combined with high resolution imaging to compare single- and multi-species bladder cell invasion events in three common uropathogens: uropathogenic Escherichia coli (UPEC), Klebsiella pneumoniae and Enterococcus faecalis. While all three species invaded the bladder cells, under flow conditions the Gram-positive E. faecalis was significantly less invasive compared to the Gram-negative UPEC and K. pneumoniae. When introduced simultaneously during an infection experiment, all three bacterial species sometimes invaded the same bladder cell, at differing frequencies suggesting complex interactions between bacterial species and bladder cells. Inside host cells, we observed encasement of E. faecalis colonies specifically by UPEC. During subsequent dispersal from the host cells, only the Gram-negative bacteria underwent infection-related filamentation (IRF). Taken together, our data suggest that bacterial multispecies invasions of single bladder cells are frequent and support earlier studies showing intraspecies cooperation on a biochemical level during UTI.

The emotional impact of uncomplicated urinary tract infections in women in China and Japan: a qualitative study

BACKGROUND

Uncomplicated urinary tract infections (uUTIs) are one of the most common community-acquired infections, particularly among women. Common symptoms of UTI include dysuria, urinary urgency and increased frequency, and lower abdominal pain. With appropriate treatment, symptoms may resolve in a few days. However, there is a lack of research on the emotional impact of this disease. We conducted a qualitative, interview-based study to gain a greater understanding of the emotional impact of uUTIs in women in China and Japan.

METHODS

A qualitative, exploratory, in-depth, interview-based study was conducted between 19 November 2020 and 25 February 2021. Women aged ≥ 18 years who experienced ≥ 1 uUTI and received antibiotic treatment in the past year were eligible for inclusion. Participants must have experienced ≥ 1 of the following symptoms during a uUTI episode: urinary urgency, frequency, dysuria, or lower abdominal/suprapubic pain. Participants who reported back pain or fever (indicative of complicated UTI) were excluded. Participants with recurrent or sporadic UTIs were included, with specific screening criteria used to ensure capture of both groups. Following a screening call, a structured, in-depth telephone interview (~ 30 min in duration) was conducted by three female external moderators trained in qualitative interviewing, assisted by an interview guide. Interviews were analysed individually and thematically, with the results presented within the identified themes.

RESULTS

A total of 65 women with uUTI completed the in-depth telephone interview: 40 (62%) from China and 25 (38%) from Japan. Participants reported that the symptoms of uUTI affected multiple aspects of their lives, and described feelings of embarrassment, frustration, guilt, dread, and loneliness associated with symptoms that interfered with relationships, work and daily activities, and sleep. Participants reported seeking healthcare from several different points of contact, from local pharmacies to hospitals.

CONCLUSIONS

Our analysis highlights the profound emotional impact of uUTIs in women in China and Japan, and the journey these participants take before their initial interaction with a healthcare professional. These insights emphasise the need to better understand the full impact of uUTI, and the role of healthcare professionals in improved patient education and support.

Deep Learning-Based Culture-Free Bacteria Detection in Urine Using Large-Volume Microscopy

Bacterial infections, increasingly resistant to common antibiotics, pose a global health challenge. Traditional diagnostics often depend on slow cell culturing, leading to empirical treatments that accelerate antibiotic resistance. We present a novel large-volume microscopy (LVM) system for rapid, point-of-care bacterial detection. This system, using low magnification (1-2×), visualizes sufficient sample volumes, eliminating the need for culture-based enrichment. Employing deep neural networks, our model demonstrates superior accuracy in detecting uropathogenic Escherichia coli compared to traditional machine learning methods. Future endeavors will focus on enriching our datasets with mixed samples and a broader spectrum of uropathogens, aiming to extend the applicability of our model to clinical samples.

Novel Antimicrobial Approaches to Combat Bacterial Biofilms Associated with Urinary Tract Infections

Urinary tract infections (UTIs) are prevalent bacterial infections in both community and healthcare settings. They account for approximately 40% of all bacterial infections and require around 15% of all antibiotic prescriptions. Although antibiotics have traditionally been used to treat UTIs for several decades, the significant increase in antibiotic resistance in recent years has made many previously effective treatments ineffective. Biofilm on medical equipment in healthcare settings creates a reservoir of pathogens that can easily be transmitted to patients. Urinary catheter infections are frequently observed in hospitals and are caused by microbes that form a biofilm after a catheter is inserted into the bladder. Managing infections caused by biofilms is challenging due to the emergence of antibiotic resistance. Biofilms enable pathogens to evade the host's innate immune defences, resulting in long-term persistence. The incidence of sepsis caused by UTIs that have spread to the bloodstream is increasing, and drug-resistant infections may be even more prevalent. While the availability of upcoming tests to identify the bacterial cause of infection and its resistance spectrum is critical, it alone will not solve the problem; innovative treatment approaches are also needed. This review analyses the main characteristics of biofilm formation and drug resistance in recurrent uropathogen-induced UTIs. The importance of innovative and alternative therapies for combatting biofilm-caused UTI is emphasised.

Diagnostic and treatment patterns in urinary and genital tract infections: insights from a referral clinic in Beirut, Lebanon

BACKGROUND

Urinary Tract Infections (UTIs) and Genital Tract Infections (GTIs) are common yet serious health concerns. Precise diagnosis is crucial due to the potential severe consequences of misdiagnosis. This study aims to distinguish between UTIs and GTIs, highlighting the importance of accurate differentiation.

MATERIALS AND METHODS

The study encompassed 294 patients, categorized into 4 groups: Group GNI (no infection, N = 57), Group GUI (urinary infection, N = 52), Group GGI (genital infection, N = 139), and Group GGUI (both infections, N = 46). Methods included patient interviews, clinical examinations, and laboratory tests such as urine and vaginal swab cultures.

RESULTS

The investigation revealed no significant differences in age, BMI, residency, or nationality across groups. However, socioeconomic status varied, with Group GNI having the lowest proportion of low socioeconomic status. In obstetrical characteristics, non-pregnancy rates were higher in Groups GUI and GGUI, with GGUI showing a notably higher abortion rate. Symptom analysis indicated lower symptom prevalence in Group GNI, with pain, itching, pruritus, and vaginal discharge being less frequent, suggesting a link between infection presence and symptom severity. Treatment patterns showed higher usage of ciprofloxacin, antifungals, and vaginal tablets in Groups GUI and GGUI. Laboratory findings highlighted significant Leucocyte Esterase presence and variations in WBC and RBC counts, particularly in Group GGUI.

CONCLUSION

The study emphasizes the need for advanced diagnostic techniques, especially those focusing on individual microbial patterns, to enhance UGTI diagnosis. Variations in symptom presentation and treatment across groups underline the necessity for personalized diagnostic and treatment strategies.

Incidence of Urinary Infections and Behavioral Risk Factors

This evaluation of the impact of behavioral risk factors on the incidence of urinary infections was based on a questionnaire in which 1103 respondents, predominantly women (883), participated. From the statistical processing of the data, it was observed that 598 of the respondents were of normal weight; the rest, more than half, were underweight or overweight (χ2 = 32.46, p < 0.001), with male respondents being predominantly overweight or obese (169 out of a total of 220). Most of the respondents were young (χ2 = 15.45, p < 0.001), under the age of 45 (840). According to the processed data, it was found that respondents in the age group of 26-35 years showed the greatest vulnerability to recurrent urinary infections, while the age group of 18-25 years recorded the highest number of responses related to the rare presence or even absence of episodes of urinary infections. A body weight-related vulnerability was also noted among the respondents; the majority of obese people declared that they face frequent episodes of urinary infections. Regarding diet quality, 210 respondents reported an adherence to an unhealthy diet, 620 to a moderately healthy diet, and 273 to a healthy diet. Of the respondents who adhered to a healthy diet, 223 were women (χ2 = 2.55, p = 0.279). There was a close connection between diet quality and the frequency of urinary infections: from the statistical processing of the data, it was observed that the highest percentage of respondents who rarely (57.14%) or never got urinary infections (29.30%) were among those who adhered to a healthy diet, and the highest percentage of those who declared that they often got urinary infections were among those with increased adherence to an unhealthy diet (χ2 = 13.46, p = 0.036). The results of this study highlight a strong impact of obesity, reduced consumption of fruit and vegetables, and sedentary lifestyle on the risk of recurring urinary infections.

Bacteriophage-based approach for treatment of urinary tract infections: a quick outlook

Urinary tract infections (UTIs) are among the most common bacterial infections affecting millions worldwide. The increasing emergence of antibiotic-resistant bacteria has become a serious concern in managing UTIs. Therefore, there is a growing interest in using bacteriophages as an alternative or adjunct therapy for UTIs. Bacteriophages are viruses that infect and kill bacteria, making them a promising tool for treating UTIs caused by antibiotic-resistant bacteria. This article provides a quick outlook on using bacteriophages to treat UTIs. We summarize the current understanding of the biology of bacteriophages, the challenges associated with developing phage-based therapies, and the promising results of several case reports and clinical trials. We also highlight the potential of phage therapy as a valuable tool in the fight against antibiotic-resistant UTIs. This quick outlook on a bacteriophage-based approach for treating UTIs offers a timely and informative summary of the current research in this field.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and lateral flow immunochromatography for rapid identification of β-lactamase-gene-harboring Enterobacterales in urine specimens: Performance and cost-benefit analyses

In this single-center prospective study, we evaluated the performance to the MALDI-ToF MS based method in conjunction with lateral flow immunochromatographic (LFIC) in urine specimens for rapid diagnosis of bacterial Urinary Tract Infection (UTI) and detection of carbapenemase and/or extended-spectrum β- lactamase (ESBL) enzymes produced by the involved bacteria, compared to standard culture, and antimicrobial susceptibility testing/genotypic resistance markers characterization performed on culture-grown colonies. In addition, a cost-benefit analysis comparing this approach against standard procedures was conducted. A total of 324 urines were included in the study, of which 288 (88.9 %) yielded concordant results by the MALDI-ToF MS and conventional culture (Kappa agreement, 0.82; P<0.001). Direct LFIC testing could be carried out in 249/324 urines. Bacterial species carrying β-lactam genotypic resistance markers were identified in 35 urines (35 CTX-M and 2 OXA-48). Two ESBL-producing Escherichia coli were missed by LFIC (Kappa agreement with standard procedures of 0.96; P<0.001). The cost-benefit analysis indicated that our novel approach resulted in an improvement of clinical outcomes (less need of outpatient care) with a marginal incremental cost (€2.59).

A Bird's-Eye View of the Pathophysiologic Role of the Human Urobiota in Health and Disease: Can We Modulate It?

For a long time, urine has been considered sterile in physiological conditions, thanks to the particular structure of the urinary tract and the production of uromodulin or Tamm-Horsfall protein (THP) by it. More recently, thanks to the development and use of new technologies, i.e., next-generation sequencing and expanded urine culture, the identification of a microbial community in the urine, the so-called urobiota, became possible. Major phyla detected in the urine are represented by Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria. Particularly, the female urobiota is largely represented by Lactobacillus spp., which are very active against urinary pathogenic Escherichia (E.) coli (UPEC) strains via the generation of lactic acid and hydrogen peroxide. Gut dysbiosis accounts for recurrent urinary tract infections (UTIs), so-called gut-bladder axis syndrome with the formation of intracellular bacterial communities in the course of acute cystitis. However, other chronic urinary tract infections are caused by bacterial strains of intestinal derivation. Monomicrobial and polymicrobial infections account for the outcome of acute and chronic UTIs, even including prostatitis and chronic pelvic pain. E. coli isolates have been shown to be more invasive and resistant to antibiotics. Probiotics, fecal microbial transplantation, phage therapy, antimicrobial peptides, and immune-mediated therapies, even including vaccines for the treatment of UTIs, will be described.

S-Nitroso-N-acetylpenicillamine impregnated latex: A new class of barrier contraception for the prevention of intercourse-associated UTIs

Urinary tract infections (UTIs) are some of the most common infections seen in humans, affecting over half of the female population. Though easily and quickly treatable, if gone untreated for too long, UTIs can lead to narrowing of the urethra as well as bladder and kidney infections. Due to the disease potential, it is crucial to mitigate the development of UTIs throughout healthcare. Unfortunately, sexual activity and the use of condoms have been identified as common risk factors for the development of sexually acquired UTIs. Therefore, this study outlines a potential alteration to existing condom technology to decrease the risk of developing sexually acquired UTIs using S-nitroso-N-acetylpenicillamine (SNAP), a nitric oxide (NO) donor. Herein, varying concentrations of SNAP are integrated into commercialized condoms through a facile solvent swelling method. Physical characterization studies showed that 72%-100% of the ultimate tensile strength was maintained with lower SNAP concentrations, validating the modified condom's mechanical integrity. Additionally, the evaluation of room-temperature storage stability via NO release analysis outlined a lack of special storage conditions needed compared to commercial products. Moreover, these samples exhibited >90% relative cell viability and >96% bacterial killing, proving biocompatibility and antimicrobial properties. SNAP-Latex maintains the desired condom durability while demonstrating excellent potential as an effective new contraceptive technology to mitigate the occurrence of sexually acquired UTIs.

Evaluating the Impact of Source-specific Order Sets for Sepsis on Empiric Antibiotic Selection in the Emergency Department

This retrospective cohort study found that implementing source-specific antibiotic order sets for sepsis in the emergency department increased appropriate empiric antibiotic selection from 51% to 74% (P = .01).

Clinical Setting Comparative Analysis of Uropathogens and Antibiotic Resistance: A Retrospective Study Spanning the Coronavirus Disease 2019 Pandemic

Background

Antimicrobial resistance (AMR) in uropathogens has been increasing in Australia. Many nations observed heightened AMR during the coronavirus disease 2019 (COVID-19) pandemic, but it is not known how this may vary across clinical settings and in nations with lower infection rates.

Methods

We investigated the uropathogen composition and corresponding antibiotic resistance of 775 559 Australian isolates from the community, hospitals, and aged care facilities before (2016-2019) and during (2020-2022) the COVID-19 pandemic. A mathematical model was developed to predict the likelihood of resistance to currently recommended antibiotics for treating urinary tract infections (UTIs).

Results

Among uropathogens originating from the community, hospitals, and aged care facilities, Escherichia coli accounted for 71.4%, 57.6%, and 65.2%, respectively. During the COVID-19 pandemic period, there was an increase in UTIs caused by E coli across all settings. Uropathogens from aged care and hospitals frequently showed higher resistance to antibiotics compared to those isolated from the community. Interestingly, AMR among uropathogens showed a declining trend during the COVID-19 pandemic. Based on the resistance patterns of the past 3 years, our modeling predicted that 30%, 42.6%, and 38.8% of UTIs in the community, hospitals, and aged care facilities, respectively, would exhibit resistance to trimethoprim treatment as empirical therapy. In contrast, resistance to nitrofurantoin was predicted to be 14.6%, 26%, and 24.1% from these 3 respective settings.

Conclusions

Empirical therapy of UTIs in Australia with trimethoprim requires evaluation due to high rates of resistance observed across clinical settings.

Recurrent urinary tract infection genetic risk: a systematic review and gene network analysis

INTRODUCTION AND HYPOTHESIS

The development of recurrent urinary tract infections (rUTIs) is not completely understood. This review is aimed at investigating the connection between genetics and rUTIs and summarizing the results of studies that have documented variations in gene expression among individuals with rUTIs compared with healthy individuals.

METHODS

A systematic search was conducted in Cochrane, Ovid, and PubMed, limiting the results to articles published between 1 January 2000, and 5 July 2022. Only studies comparing the difference in gene expression between individuals with rUTI and healthy individuals utilizing molecular techniques to measure gene expression in blood or urine samples were included in this systematic review. Gene network and pathways analyses were performed using Cytoscape software, with input data obtained from our systematic review of differentially expressed genes in rUTIs.

RESULTS

Six studies met our criteria for inclusion. The selected studies used molecular biology methods to quantify gene expression data from blood specimens. The analysis revealed that gene expressions of CXCR1 and TLR4 decreased, whereas CXCR2, TRIF, and SIGIRR increased in patients with rUTI compared with healthy controls. The analysis demonstrated that the most significant pathways were associated with TLR receptor signaling and tolerance, I-kappa B kinase/NF-kappa B signaling, and MyD88-independent TLR signaling.

CONCLUSIONS

This systematic review uncovered gene expression variations in several candidate genes and identified a number of underlying biological pathways associated with rUTIs. These findings could shift the treatment and prevention strategies for rUTIs.

Microscopic urinary particle detection by different YOLOv5 models with evolutionary genetic algorithm based hyperparameter optimization

The diagnosis of kidney disease often involves analysing urine sediment particles. Traditionally, urinalysis was performed manually by collecting urine samples and using a centrifuge, which was prone to manual errors and relied on labour-intensive processes. Automated urine sediment microscopy, based on machine learning models, requires segmentation and feature extraction, which can hinder model performance due to intrinsic characteristics of microscopic images. Deep learning models based on convolutional neural networks (CNNs) often rely on a large number of manually annotated data, making the system computationally complex. This study propose an advanced deep learning model based on YOLOv5, which offers faster performance and requires comparatively less data. The proposed model used five variants of the YOLOv5 model (YOLOv5n, YOLOv5s, YOLOv5m, YOLOv5l, and YOLOv5x) to detect six categories of urine particles (erythrocyte, leukocyte, crystals, cast, mycete, epithelial cells) from microscopic urine sediment images. The dataset involved 5376 images of urine sediments with 6 particles. There are 30 sets of hyperparamreteres are employed in the YOLOv5 model. To optimize the hyperparameters and fine-tune with the urine sediment dataset and for training each model, the system employed a genetic algorithm (GA) based on evolutionary principles named as Evolutionary Genetic Algorithm (EGA). Among the six categories of detected particles mycete achieved maximum performance with a mAP of 97.6 % and crystals achieved minimum performance with a mAP of 81.7 % with YOLOv5x model compared to other particles. To optimize the hyperparameters for training each model, the system employed a genetic algorithm (GA) based on evolutionary principles named as Evolutionary Genetic Algorithm (EGA). Among all the models, YOLOv5l and YOLOv5x performed the best. YOLOv5l achieved a mean average precision (mAP) of 85.8 % while YOLOv5x achieved a mAP of 85.4 % at an IoU threshold of 0.5. The detection speed per image was 23.4 ms for YOLOv5l and 28.4 ms for YOLOv5x. The proposed method developed a faster and better automated microscopic model using advanced deep learning techniques to detect urinary particles from microscopic urine sediment images for kidney disease identification. The method demonstrated strong performance in urinalysis.

Impact of Preoperative Urinary Tract Infection Screening in Asymptomatic Women Undergoing Midurethral Sling

INTRODUCTION

There is limited information regarding the utility of preoperative urine culture (Ucx) screening to decrease postoperative UTI rates following midurethral sling (MUS).

HYPOTHESIS

The primary objective of this study was to determine if the rate of postoperative UTI within the first 6 weeks after surgery is lower in women undergoing MUS when preoperative Ucx is obtained compared to when it is not. Secondary objectives were to determine clinical factors associated with postoperative UTI risk.

METHODS

This is a retrospective cohort study of women who did not have symptoms of or a diagnosis of cystitis at the time of their preoperative evaluation and are undergoing MUS. Patients were grouped into those who had preoperative Ucx screening within 6 weeks preceding surgery and those who did not. UTI rates 6 weeks following surgery were compared between groups. Additionally, factors impacting the risk of developing a UTI within 6 weeks of surgery were assessed.

RESULTS

Among 661 patients, 13.2% had a UTI within the first 6 weeks. There was no significant difference in UTI rates between those who did and did not have preoperative Ucx, respectively (14.9% vs 10.2%, p = 0.09). On multivariable analysis, current smoker status (OR 3.02, 95% CI 1.10-8.26), history of recurrent UTI (OR 3.00, 95% CI 1.14-7.86), and requiring postoperative SIC (OR 8.75, 95% CI 1.83-41.74) were independently associated with a UTI within 6 weeks of MUS.

CONCLUSION

Obtaining preoperative Ucx in asymptomatic women prior to MUS does not appear to be associated with lower postoperative UTIs rates within 6 weeks of surgery.

Uropathogenic bacteria and deductive genomics towards antimicrobial resistance, virulence, and potential drug targets

Urinary tract infections (UTIs) are among the most prevalent bacterial infections affecting people in inpatient and outpatient settings. The current study aimed to sequence the genome of uropathogenic Escherichia coli strain CUI-B1 resourced from a woman having uncomplicated cystitis and pyelonephritis. Followed by deductive genomics towards potential drug targets using E. coli strain CUI-B1, strain O25b: H4-ST131, Proteus mirabilis strain HI4320, Klebsiella pneumoniae strain 1721, and Staphylococcus saprophyticus strain ATCC 15305 uropathogenic strains. Comparative genome analysis revealed that genes related to the survival of E. coli, P. mirabilis, K. pneumoniae, and S. saprophyticus, such as genes of metal-requiring proteins, defense-associated genes, and genes associated with general physiology, were found to be highly conserved in the genomes including strain CUI-B1. However, the genes responsible for virulence and drug resistance, mainly those that are involved in bacterial secretion, fimbriae, adherence, and colonization, were found in various genomic regions and varied from one species to another or within the same species. Based on the genome sequence, virulence, and antimicrobial-resistant gene dataset, the subtractive proteomics approach revealed 22 proteins mapped to the pathogen's unique pathways and among them, entB, clbH, chuV, and ybtS were supposed to be potential drug targets and the single drug could be utilized for all above-mentioned strains. These results may provide the foundation for the optimal target for future discovery of drugs for E. coli-, P. mirabilis-, K. pneumoniae-, and S. saprophyticus-based infections and could be investigated further to employ in personalized drug development.

Urine biomarkers individually and as a consensus model show high sensitivity and specificity for detecting UTIs

BACKGROUND

Current diagnoses of urinary tract infection (UTI) by standard urine culture (SUC) has significant limitations in sensitivity, especially for fastidious organisms, and the ability to identify organisms in polymicrobial infections. The significant rate of both SUC "negative" or "mixed flora/contamination" results in UTI cases and the high prevalence of asymptomatic bacteriuria indicate the need for an accurate diagnostic test to help identify true UTI cases. This study aimed to determine if infection-associated urinary biomarkers can differentiate definitive UTI cases from non-UTI controls.

METHODS

Midstream clean-catch voided urine samples were collected from asymptomatic volunteers and symptomatic subjects ≥ 60 years old diagnosed with a UTI in a urology specialty setting. Microbial identification and density were assessed using a multiplex PCR/pooled antibiotic susceptibility test (M-PCR/P-AST) and SUC. Three biomarkers [neutrophil gelatinase-associated lipocalin (NGAL), and Interleukins 8 and 1β (IL-8, and IL-1β)] were also measured via enzyme-linked immunosorbent assay (ELISA). Definitive UTI cases were defined as symptomatic subjects with a UTI diagnosis and positive microorganism detection by SUC and M-PCR, while definitive non-UTI cases were defined as asymptomatic volunteers.

RESULTS

We observed a strong positive correlation (R2 > 0.90; p < 0.0001) between microbial density and the biomarkers NGAL, IL-8, and IL-1β for symptomatic subjects. Biomarker consensus criteria of two or more positive biomarkers had sensitivity 84.0%, specificity 91.2%, positive predictive value 93.7%, negative predictive value 78.8%, accuracy 86.9%, positive likelihood ratio of 9.58, and negative likelihood ratio of 0.17 in differentiating definitive UTI from non-UTI cases, regardless of non-zero microbial density. NGAL, IL-8, and IL-1β showed a significant elevation in symptomatic cases with positive microbe identification compared to asymptomatic cases with or without microbe identification. Biomarker consensus exhibited high accuracy in distinguishing UTI from non-UTI cases.

CONCLUSION

We demonstrated that positive infection-associated urinary biomarkers NGAL, IL-8, and IL-1β, in symptomatic subjects with positive SUC and/or M-PCR results was associated with definitive UTI cases. A consensus criterion with ≥ 2 of the biomarkers meeting the positivity thresholds showed a good balance of sensitivity (84.0%), specificity (91.2%), and accuracy (86.9%). Therefore, this biomarker consensus is an excellent supportive diagnostic tool for resolving the presence of active UTI, particularly if SUC and M-PCR results disagree.

Antimicrobial Agent Functional Gold Nanocluster-Mediated Multichannel Sensor Array for Bacteria Sensing

Urinary tract infections (UTIs) have greatly affected human health in recent years. Accurate and rapid diagnosis of UTIs can enable a more effective treatment. Herein, we developed a multichannel sensor array for efficient identification of bacteria based on three antimicrobial agents (vancomycin, lysozyme, and bacitracin) functional gold nanoclusters (AuNCs). In this sensor, the fluorescence intensity of the three AuNCs was quenched to varying degrees by the bacterial species, providing a unique fingerprint for different bacteria. With this sensing platform, seven pathogenic bacteria, different concentrations of the same bacteria, and even bacterial mixtures were successfully differentiated. Furthermore, UTIs can be accurately identified with our sensors in ∼30 min with 100% classification accuracy. The proposed sensing systems offer a rapid, high-throughput, and reliable sensing platform for the diagnosis of UTIs.

International travel increases risk of urinary tract infection caused by extended-spectrum beta-lactamase-producing Enterobacterales-three-arm case-control study

BACKGROUND

Extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-PE) have worldwide become increasingly prevalent as pathogens causing urinary tract infections (UTIs), posing challenges in their treatment. Of particular concern are travellers to low- and middle-income countries (LMICs), a substantial proportion of whom become colonized by ESBL-PE, with UTIs as the most common clinical manifestation. Seeking tools for preventing ESBL-PE UTI, we explored factors associated with (i) any UTI (versus control), (ii) ESBL-PE UTI (versus control) and (iii) ESBL-PE versus non-ESBL-PE UTI.

METHODS

During 2015-20, we recruited patients with recent ESBL-PE or non-ESBL-PE UTIs, and controls with no UTI to fill in questionnaires covering potential (ESBL-PE-)UTI risk factors.

RESULTS

Of our 430 participants, 130 had ESBL-PE UTI and 187 non-ESBL-PE UTI; 113 were controls. Our three comparisons showed several risk factors as exemplified for any UTI versus controls by female sex, lower education, age, diabetes, antibiotic use, diarrhoea; for ESBL-PE UTI versus controls by travel to LMICs, antibiotic use, swimming; and ESBL-PE versus non-ESBL-PE UTI by male sex, higher education, LMIC travel (participant/household member), pets and antibiotic use. Weekly fish meals appeared protective against both UTI and ESBL-PE UTI.

CONCLUSIONS

Of the numerous factors predisposing to UTI and/or ESBL-PE UTI, our study highlights antibiotic use and LMIC travel. Household members' LMIC travel appears to pose a risk of ESBL-PE UTI, pointing to household transmission of travel-acquired uropathogens. As predisposing factors to multidrug-resistant UTI, international travel and antibiotic use constitute practical targets for prevention efforts.

Comparative genomic analysis of uropathogenic Escherichia coli strains from women with recurrent urinary tract infection

Introduction

Recurrent urinary tract infections (RUTIs) caused by uropathogenic Escherichia coli are costly public health problems impacting patients' quality of life.

Aim

In this work, a comparative genomics analysis of three clinical RUTI strains isolated from bladder biopsy specimens was performed.

Materials and methods

One hundred seventy-two whole genomes of urinary tract E. coli strains were selected from the NCBI database. The search for virulence factors, fitness genes, regions of interest, and genetic elements associated with resistance was manually carried out. The phenotypic characterization of antibiotic resistance, haemolysis, motility, and biofilm formation was performed. Moreover, adherence and invasion assays with human bladder HTB-5 cells, and transmission electron microscopy (TEM) were performed.

Results

The UTI-1_774U and UTI-3_455U/ST1193 strains were associated with the extraintestinal pathotypes, and the UTI-2_245U/ST295 strain was associated with the intestinal pathotype, according to a phylogenetic analysis of 172 E. coli urinary strains. The three RUTI strains were of clinical, epidemiological, and zoonotic relevance. Several resistance genes were found within the plasmids of these strains, and a multidrug resistance phenotype was revealed. Other virulence genes associated with CFT073 were not identified in the three RUTI strains (genes for type 1 and P fimbriae, haemolysin hlyA, and sat toxin). Quantitative adherence analysis showed that UTI-1_774U was significantly (p < 0.0001) more adherent to human bladder HTB-5 cells. Quantitative invasion analysis showed that UTI-2_245U was significantly more invasive than the control strains. No haemolysis or biofilm activity was detected in the three RUTI strains. The TEM micrographs showed the presence of short and thin fimbriae only in the UTI-2_245U strain.

Conclusion

The high variability and genetic diversity of the RUTI strains indicate that are a mosaic of virulence, resistance, and fitness genes that could promote recurrence in susceptible patients.

Genomic characterization of a multidrug-resistant uropathogenic Escherichia coli and evaluation of Echeveria plant extracts as antibacterials

Uropathogenic Escherichia coli (UPEC) is the most common bacterial agent associated with urinary tract infections, threatening public health systems with elevated medical costs and high morbidity rates. The successful establishment of the infection is associated with virulence factors encoded in its genome, in addition to antibacterial resistance genes, which could limit the treatment and resolution of the infection. In this sense, plant extracts from the genus Echeveria have traditionally been used to treat diverse infectious diseases. However, little is known about the effects of these extracts on bacteria and their potential mechanisms of action. This study aims to sequence a multidrug-resistant UPEC isolate (UTI-U7) and assess the multilocus sequence typing (MLST), virulence factors, antimicrobial resistance profile, genes, serotype, and plasmid content. Antimicrobial susceptibility profiling was performed using the Kirby-Bauer disk diffusion. The antibacterial and anti-adherent effects of the methanol extracts (ME) of Echeveria (E. craigiana, E. kimnachii, and E. subrigida) against UTI-U7 were determined. The isolate was characterized as an O25:H4-B2-ST2279-CH40 subclone and had resistant determinants to aminoglycosides, β-lactams, fluoroquinolones/quinolones, amphenicols, and tetracyclines, which matched with the antimicrobial resistance profile. The virulence genes identified encode adherence factors, iron uptake, protectins/serum resistance, and toxins. Identified plasmids belonged to the IncF group (IncFIA, IncFIB, and IncFII), alongside several prophage-like elements. After an extensive genome analysis that confirmed the pathogenic status of UTI-U7 isolate, Echeveria extracts were tested to determine their antibacterial effects; as an extract, E. subrigida (MIC, 5 mg/mL) displayed the best inhibitory effect. However, the adherence between UTI-U7 and HeLa cells was unaffected by the ME of the E. subrigida extract.

Utilizing the drug repurposing strategy on current drugs: new leads for peptic ulcers via biochemical and biomolecular dynamics studies

The hyperactivity of urease enzymes plays a crucial role in the development of hepatic coma, hepatic encephalopathy, urolithiasis, gastric and peptic ulcers. Additionally, these enzymes adversely impact the soil's nitrogen efficiency for crop production. In the current study 100 known drugs were tested against Jack Bean urease and Proteus mirabilis urease and identified three inhibitors i.e. terbutaline (compound 1), Ketoprofen (compound 2) and norepinephrine bitartrate (compound 3). As a result, these compounds showed excellent inhibition against Jack Bean urease i.e. (IC50 = 2.1-11.3 µM), and Proteus mirabilis urease (4.8-11.9 µM). Moreover, in silico studies demonstrate maximum interactions of compounds in the enzyme's active site. Furthermore, intermolecular interactions between compounds and enzyme atoms were examined using STD-NMR spectrophotometry. In parallel, molecular dynamics simulation was carried out to study compounds dynamic behavior within the urease binding region. Urease remained stable during most of the simulation time and ligands were bound in the protein active pocket as observed from the Root mean square deviation (RMSD) and ligand RMSD analyses. Furthermore, these compounds display interactions with the crucial residues, including His492 and Asp633, in 100 ns simulations. In the binding energy analysis, norepinephrine bitartrate exhibited the highest binding energy (-76.32 kcal/mol) followed by Ketoprofen (-65.56 kcal/mol) and terbutaline (-62.15 kcal/mol), as compared to acetohydroxamic acid (-52.86 kcal/mol). The current findings highlight the potential of drug repurposing as an effective approach for identifying novel anti-urease compounds.Communicated by Ramaswamy H. Sarma.

Global emergence of a hypervirulent carbapenem-resistant Escherichia coli ST410 clone

Carbapenem-resistant Escherichia coli (CREC) ST410 has recently emerged as a major global health problem. Here, we report a shift in CREC prevalence in Chinese hospitals between 2017 and 2021 with ST410 becoming the most commonly isolated sequence type. Genomic analysis identifies a hypervirulent CREC ST410 clone, B5/H24RxC, which caused two separate outbreaks in a children's hospital. It may have emerged from the previously characterised B4/H24RxC in 2006 and has been isolated in ten other countries from 2015 to 2021. Compared with B4/H24RxC, B5/H24RxC lacks the blaOXA-181-bearing X3 plasmid, but carries a F-type plasmid containing blaNDM-5. Most of B5/H24RxC also carry a high pathogenicity island and a novel O-antigen gene cluster. We find that B5/H24RxC grew faster in vitro and is more virulent in vivo. The identification of this newly emerged but already globally disseminated hypervirulent CREC clone, highlights the ongoing evolution of ST410 towards increased resistance and virulence.

Occurrence of Imipenem-Resistant Uropathogenic Escherichia coli in Pregnant Women: An Insight into Their Virulence Profile and Clonal Structure

Uropathogenic Escherichia coli (UPEC) is the predominant pathogen in Urinary Tract Infection (UTI) in pregnant and non-pregnant women. Limited studies were initiated to explore UPEC from pregnant women with respect to imipenem resistance, pathogenicity, and their clonal lineage. In this study, imipenem resistance, phylogenetic background, virulence-associated genes, and clonal characteristics in UPECs isolated from pregnant and non-pregnant cohorts were investigated. E. coli was identified biochemically from urine culture-positive samples from pregnant and non-pregnant women. Carbapenem (meropenem, ertapenem, imipenem) susceptibility was determined by Kirby-Bauer disk diffusion test. The pathogenic determinants were identified by PCR. MEGA 11 was used to interpret clonal lineages from MLST. GraphPad Prism 8.0 and SPSS 26.0 were used for statistical interpretation. Results indicated highest resistance against imipenem compared to meropenem and ertapenem in UPECs isolated from pregnant (UPECp; 63.89%) and non-pregnant (UPECnp; 87.88%) women. Although phylogroup E was predominant in both imipenem-resistant isolates, acquisition of virulence factors was higher among UPECnp than UPECp. Akin to this observation, the presence of PAI III536 and PAI IV536 was statistically significant (p < 0.05) in the former. MLST analysis revealed similar clonal lineages between UPECnp and UPECp, which showed an overall occurrence of ST405 followed by ST101, ST410, ST131, and ST1195 in UPECnp and ST167 in UPECp, respectively, with frequent occurrence of CC131, CC405. Therefore, imipenem-resistant UPECp although discrete with respect to their virulence determinants when compared to UPECnp shared similar STs and CCs, which implied common evolutionary history. Thus, empiric treatment must be restricted in UTIs to especially protect maternal and fetal health.

Increasing community prevalence of extended-spectrum beta-lactamase-producing Escherichia coli in urine is associated with increasing district-level antibiotic consumption

This study aimed to analyze ESBL-producing Escherichia coli prevalence in urine samples collected between 2011-2019 in Curitiba, a large city in Brazil, and relating it to antibiotic consumption and sanitary conditions. This is a longitudinal study correlating prevalence of ESBL-producing E. coli isolates from urine samples with district-level antibiotic consumption and sociodemographic data during 2011-2019. E. coli isolates were tested for antibiotic susceptibility and ESBL by an automated method. Statistical analysis applied linear regressions, pooled ordinary least squares, and fixed effects models for districts or years. The Chow and Hausman tests indicated that the fixed effects model for individual districts fitted best. Chi-square test was used for qualitative variables (statistical significance was set when P < 0.05). Among the 886 535 urine sample cultures, 9.9% of isolates were ESBL-producing E. coli. Their prevalence increased from 4.7% in 2012 to 19.3% in 2019 (P < 0.0001; R2 = 0.922). This progressive increase correlated with age (P = 0.007; R2 = 0.8725) and male gender (P < 0.001) and increased antibiotic consumption (P = 0.0386; R2 = 0.47). The fixed effects model showed that district influences ESBL prevalence and that antibiotic consumption explains 20%-30% of this variation, with an increase of one defined daily dose accounting for an increase of 0.02084 percentage points of ESBL. The increasing prevalence of ESBL-producing E. coli can, to a considerable extent, be explained by increasing antibiotic consumption.

Update on Urinary Tract Infection Antibiotic Resistance-A Retrospective Study in Females in Conjunction with Clinical Data

Urinary tract infections (UTIs) represent a frequent pathology among the female population that has become more and more difficult to treat in the past decade, considering the increase in antibiotic resistance-a serious global public health problem. A cross-sectional retrospective study was conducted for six months to report an update regarding the rates of resistance and susceptibility of uropathogens necessary for optimal treatment. A total of 5487 patients were screened, of which 524 (9.54%) were female patients who met the criteria for inclusion in the study. Escherichia coli was the most common pathogen, representing 290 cases (55.34%), followed by Enterococcus spp. 82 (15.64%). Escherichia coli presented the highest resistance to amoxicillin-clavulanic acid (R = 33.1%), followed by trimethoprim-sulfamethoxazole (R = 32.41%) and levofloxacin (R = 32.06%). The highest sensitivity rates were observed for fosfomycin (S = 96.55%), followed by imipenem (S = 93.1%). Enterococcus spp. showed the highest resistance to levofloxacin (R = 50.0%), followed by penicillin (R = 39.02%). The highest sensitivity was observed for fosfomycin (S = 90.24%), linezolid (S = 89.02%), and nitrofurantoin (S = 86.58%). The second most frequent Gram-negative uropathogen was represented by Klebsiella spp., which had the highest resistance to amoxicillin-clavulanic acid (R = 35.89%), followed by levofloxacin (R = 25.64) and trimethoprim-suflamethoxazole (R = 24.35%). The most frequently associated pathology was an episode of UTI in the previous year, followed by diabetes and chronic kidney disease. Antibiotic resistance is a serious problem for all clinicians who treat UTIs. An up-to-date knowledge of antibiotic resistance rates is a major necessity to stop its evolution. Overall, the highest resistance rates were observed for aminopenicillins, fluoroquinolones, and trimethoprim-sulfamethoxazole. The best susceptibility rates were observed for fosfomycin, nitrofurantoin, and carbapenems. Our report aims to guide clinicians whenever they are forced to prescribe antibiotics empirically.

Pathogen non-planktonic phases within the urinary tract impact early infection and resistance evolution

Treatment of urinary tract infections and the prevention of their recurrence is a pressing global health problem. In a urinary infection, pathogenic bacteria not only reside in the bladder lumen but also attach to and invade the bladder tissue. Planktonic, attached, and intracellular bacteria face different selection pressures from physiological processes such as micturition, immune response, and antibiotic treatment. Here, we use a mathematical model of the initial phase of infection to unravel the effects of these different selective pressures on the ecological and evolutionary dynamics of urinary infections. We explicitly model planktonic bacteria in the bladder lumen, bacteria attached to the bladder wall, and bacteria that have invaded the epithelial cells of the bladder. We find that the presence of non-planktonic bacteria substantially increases the risk of infection establishment and affects evolutionary trajectories leading to resistance during antibiotic treatment. We also show that competitive inoculation with a fast-growing non-pathogenic strain can reduce the pathogen load and increase the efficacy of an antibiotic, but only if the antibiotic is used in moderation. Our study shows that including different compartments is essential to create more realistic models of urinary infections, which may help guide new treatment strategies.

Lower Urinary Tract Inflammation and Infection: Key Microbiological and Immunological Aspects

The urinary system, primarily responsible for the filtration of blood and waste, is affected by several infectious and inflammatory conditions. Focusing on the lower tract, this review outlines the physiological and immune landscape of the urethra and bladder, addressing key immunological and microbiological aspects of important infectious/inflammatory conditions. The conditions addressed include urethritis, interstitial cystitis/bladder pain syndrome, urinary tract infections, and urosepsis. Key aspects of each condition are addressed, including epidemiology, pathophysiology, and clinical considerations. Finally, therapeutic options are outlined, highlighting gaps in the knowledge and novel therapeutic approaches.

Prevalence and antimicrobial resistance profile of pathogens isolated from patients with urine tract infections admitted to a university hospital in a medium-sized Brazilian city

This study aimed to determine the antibiotic profile of microorganisms isolated from urine samples of patients with community urine tract infections (UTI) admitted to the University Hospital of the Federal University of Sao Carlos to support an appropriate local empirical treatment. A retrospective cross-sectional study was conducted from October 2018 to October 2020. Data from 1,528 positive urine cultures for bacterial pathogens and antibiograms were tabulated. Bacterial species prevalence and their resistance profile were analyzed and compared by sex and age. For Gram-negative fermenting bacteria, resistance rates were compared between patients with previous hospitalization and the total of infections caused by this group. For comparisons, the Chi-square test was performed, using Fisher's exact test when necessary (BioEstat program, adopting p ≤ 0.05). A multivariate analysis was applied to assess the effect of the studied variables in predicting multidrug resistance. Infections were more prevalent in women and older adults. Gram-negative bacteria represented 90.44% of total cultures. In both sexes, E. coli prevalence was significantly higher in adults compared with older adults (p < 0.0001). For several antibiotics, resistance rates were higher in the older adults compared with other ages and in patients with Gram-negative fermenting infections and previous hospitalization compared with the total of infections by this group of bacteria. The closer to the hospitalization, the higher the number of antibiotics with superior resistance rates. Resistance rates for aminoglycosides, carbapenems, ceftazidime, nitrofurantoin, piperacillin+tazobactam, and fosfomycin were less than 20%, considered adequate for empirical treatment. Only hospitalization in the previous 90 days was statistically significant in predicting infections by multidrug-resistant bacteria.

A personalized prediction model for urinary tract infections in type 2 diabetes mellitus using machine learning

Patients with type 2 diabetes mellitus (T2DM) are at higher risk for urinary tract infections (UTIs), which greatly impacts their quality of life. Developing a risk prediction model to identify high-risk patients for UTIs in those with T2DM and assisting clinical decision-making can help reduce the incidence of UTIs in T2DM patients. To construct the predictive model, potential relevant variables were first selected from the reference literature, and then data was extracted from the Hospital Information System (HIS) of the Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital for analysis. The data set was split into a training set and a test set in an 8:2 ratio. To handle the data and establish risk warning models, four imputation methods, four balancing methods, three feature screening methods, and eighteen machine learning algorithms were employed. A 10-fold cross-validation technique was applied to internally validate the training set, while the bootstrap method was used for external validation in the test set. The area under the receiver operating characteristic curve (AUC) and decision curve analysis (DCA) were used to evaluate the performance of the models. The contributions of features were interpreted using the SHapley Additive ExPlanation (SHAP) approach. And a web-based prediction platform for UTIs in T2DM was constructed by Flask framework. Finally, 106 variables were identified for analysis from a total of 119 literature sources, and 1340 patients were included in the study. After comprehensive data preprocessing, a total of 48 datasets were generated, and 864 risk warning models were constructed based on various balancing methods, feature selection techniques, and a range of machine learning algorithms. The receiver operating characteristic (ROC) curves were used to assess the performances of these models, and the best model achieved an impressive AUC of 0.9789 upon external validation. Notably, the most critical factors contributing to UTIs in T2DM patients were found to be UTIs-related inflammatory markers, medication use, mainly SGLT2 inhibitors, severity of comorbidities, blood routine indicators, as well as other factors such as length of hospital stay and estimated glomerular filtration rate (eGFR). Furthermore, the SHAP method was utilized to interpret the contribution of each feature to the model. And based on the optimal predictive model a user-friendly prediction platform for UTIs in T2DM was built to assist clinicians in making clinical decisions. The machine learning model-based prediction system developed in this study exhibited favorable predictive ability and promising clinical utility. The web-based prediction platform, combined with the professional judgment of clinicians, can assist to make better clinical decisions.

A Common Polymorphism in RNASE6 Impacts Its Antimicrobial Activity toward Uropathogenic Escherichia coli

Human Ribonuclease (RNase) 6 is a monocyte and macrophage-derived protein with potent antimicrobial activity toward uropathogenic bacteria. The RNASE6 gene is heterogeneous in humans due to the presence of single nucleotide polymorphisms (SNPs). RNASE6 rs1045922 is the most common non-synonymous SNP, resulting in a G to A substitution that determines an arginine (R) to glutamine (Q) transversion at position 66 in the protein sequence. By structural analysis we observed that R66Q substitution significantly reduces the positive electrostatic charge at the protein surface. Here, we generated both recombinant RNase 6-R66 and -Q66 protein variants and determined their antimicrobial activity toward uropathogenic Escherichia coli (UPEC), the most common cause of UTI. We found that the R66 variant, encoded by the major SNP rs1045922 allele, exhibited superior bactericidal activity in comparison to the Q66 variant. The higher bactericidal activity of R66 variant correlated with an increase in the protein lipopolysaccharide binding and bacterial agglutination abilities, while retaining the same enzymatic efficiency. These findings encourage further work to evaluate RNASE6 SNP distribution and its impact in UTI susceptibility.

Microbial co-occurrences on catheters from long-term catheterized patients

Catheter-associated urinary tract infections (CAUTIs), a common cause of healthcare-associated infections, are caused by a diverse array of pathogens that are increasingly becoming antibiotic resistant. We analyze the microbial occurrences in catheter and urine samples from 55 human long-term catheterized patients collected over one year. Although most of these patients were prescribed antibiotics over several collection periods, their catheter samples remain colonized by one or more bacterial species. Examination of a total of 366 catheter and urine samples identify 13 positive and 13 negative genus co-occurrences over 12 collection periods, representing associations that occur more or less frequently than expected by chance. We find that for many patients, the microbial species composition between collection periods is similar. In a subset of patients, we find that the most frequently sampled bacteria, Escherichia coli and Enterococcus faecalis, co-localize on catheter samples. Further, co-culture of paired isolates recovered from the same patients reveals that E. coli significantly augments E. faecalis growth in an artificial urine medium, where E. faecalis monoculture grows poorly. These findings suggest novel strategies to collapse polymicrobial CAUTI in long-term catheterized patients by targeting mechanisms that promote positive co-associations.

Oxybutynin ameliorates LPS-induced inflammatory response in human bladder epithelial cells

Urinary tract infection (UTI) mainly results from bacterial infections in the urinary tract and markedly impacts the normal lives of millions of patients worldwide. The infection and damage to urethral epithelial cells is the first and key step of UTI development and is a critical target for treating clinical UTI. Oxybutynin, an agent for treating urinary incontinence, is recently claimed with protective effects on bladder ultrastructure. Our study will assess the impact of Oxybutynin on inflammation in lipopolysaccharide (LPS)-stimulated bladder epithelial cells. Bladder epithelial T24 cells were treated with 1 μg/mL LPS with or without 10 and 20 μM Oxybutynin for 24 h. Increased levels of oxidative stress (OS) biomarkers, such as reactive oxygen species, 8-hydroxy-2'-deoxyguanosine, malondialdehyde, as well as upregulated inducible nitric oxide synthase and promoted release of nitric oxide, were observed in LPS-managed T24 cells, all of which were signally suppressed by Oxybutynin. Furthermore, severe inflammatory responses, including enhanced release of cytokines, upregulated matrix metallopeptidase-2 (MMP-2) and MMP-9, and raised monocyte chemoattractant protein-1 level, were found in LPS-challenged T24 cells, which were markedly reversed by Oxybutynin. Moreover, the activated toll-1ike receptor 4/nuclear factor-κB pathway observed in LPS-managed T24 cells was repressed by Oxybutynin. Collectively, Oxybutynin mitigated LPS-induced inflammatory response in human bladder epithelial cells.

β-defensin 2 protects against Escherichia coli-induced acute urinary tract infection by downregulating β-catenin

β-defensin 2 (BD2) is a small cationic peptide that exerts a critical role in host defense against bacterial infections. Here, we aimed to investigate the role of BD2 in protecting against acute urinary tract infection (AUTI) caused by Escherichia coli (UPEC). Here, LPS-induced human urinary bladder epithelial cell (HCV-29) model and UPEC-induced mice model were used for assessing AUTI. Visceral organ lesions of mice following treatment was assessed by HE staining. Cell viability was determined by CCK-8 assay. Permeability in HCV-29 cells was analyzed in Transwell assay. Expression of inflammatory factors (IL-1β, IL-6, and TNF-α) was measured by ELISA assay. The levels of BD2, β-catenin and tight-junction proteins (ZO-1, Occludin, and Claudin-1) were detected by RT-qPCR, western blotting, immunofluorescence or immunohistochemistry. Our results showed that BD2 was lowly expressed and β-catenin showed the reverse trend in response to bacterial infection in vitro and in vivo. BD2 overexpression alleviated the decreased cell viability, increased cell permeability, upregulation of inflammatory factors, downregulation of tight-junction protein and high β-catenin expression in LPS-induced HCV-29 cells, which may contribute to the negative regulation of β-catenin expression. Furthermore, BD2 overexpression attenuated the bacterial infection of tissues, high levels of inflammatory factors and β-catenin, and low levels of tight-junction proteins in mice stimulated with UPEC. This study showed that BD2 played a crucial role in protecting against AUTI caused by gram-negative bacteria through suppressing β-catenin expression. Targeting BD2 may provide a potential therapeutic approach for the prevention and treatment of AUTI.

An emerging strategy: probiotics enhance the effectiveness of tumor immunotherapy via mediating the gut microbiome

The occurrence and progression of tumors are often accompanied by disruptions in the gut microbiota. Inversely, the impact of the gut microbiota on the initiation and progression of cancer is becoming increasingly evident, influencing the tumor microenvironment (TME) for both local and distant tumors. Moreover, it is even suggested to play a significant role in the process of tumor immunotherapy, contributing to high specificity in therapeutic outcomes and long-term effectiveness across various cancer types. Probiotics, with their generally positive influence on the gut microbiota, may serve as effective agents in synergizing cancer immunotherapy. They play a crucial role in activating the immune system to inhibit tumor growth. In summary, this comprehensive review aims to provide valuable insights into the dynamic interactions between probiotics, gut microbiota, and cancer. Furthermore, we highlight recent advances and mechanisms in using probiotics to improve the effectiveness of cancer immunotherapy. By understanding these complex relationships, we may unlock innovative approaches for cancer diagnosis and treatment while optimizing the effects of immunotherapy.

Comparing ceftolozane/tazobactam versus piperacillin/tazobactam for the initial empiric therapy of urinary tract infections: A retrospective comparative study

INTRODUCTION

This study compares the clinical and microbiological efficacy of ceftolozane/tazobactam (CTLZ/TAZ) and piperacillin/tazobactam (PIPC/TAZ) for treating complicated cystitis or acute pyelonephritis.

METHODS

Patients who had been treated with empiric antibiotics, CTLZ/TAZ (52 cases) or PIPC/TAZ (47 cases), due to urinary tract infections (UTIs) were eligible for this study. Patients' demographic backgrounds, types of UTIs, and causative microorganisms isolated from urine or blood bacterial cultures were collected. Short-term clinical efficacy at the end of the initial empiric therapy, long-term clinical efficacy including sequential antibiotic treatments (nonrecurrence rate within 1 month after the initial empiric therapy), and microbiological efficacy were retrospectively compared in both CTLZ/TAZ and PIPC/TAZ groups.

RESULTS

Complicated UTIs were present in most eligible patients, and no significant difference in the patients' background was observed between the two groups. Escherichia coli and Enterococcus faecalis were the most common microorganisms isolated from urine culture in both groups. The short-term clinical effective rate of CTLZ/TAZ and PIPC/TAZ was 80.8% and 87.2%, respectively. For long-term clinical efficacy, the nonrecurrence rate of UTIs was present in 95.1% and 89.7% of patients with CTLZ/TAZ and PIPC/TAZ, respectively. No significant difference was observed in the short- and long-term effects between the two groups. The microbiological efficacy of the CTLZ/TAZ and PIPC/TAZ groups was 72.7% and 86.0%, respectively. No significant difference in microbiological effects was also observed between the two groups.

CONCLUSIONS

This study demonstrated the noninferiority of CTLZ/TAZ to PIPC/TAZ, suggesting that CTLZ/TAZ is an alternative antibiotic used as empiric therapy for UTIs.

Microbial Transfer by Intermittent Catheters: An In Vitro Evaluation of Microbial Transfer in Catheter With Variable Protective Features

PURPOSE

The purpose of this study was to evaluate the effects of various protective features (eg, catheter cap, introducer tip, and catheter sleeve) of hydrophilic intermittent catheters against contamination with urinary tract infection-associated microorganisms using an in vitro model.

DESIGN

An in vitro study of microbial transfer.

MATERIALS AND METHODS

Gloves were contaminated with uropathogenic microorganisms and used to simulate intermittent catheterization of male anatomical models with and without the protective features present in 5 commercially available hydrophilic catheters. Using this contaminated touch transfer method, both the meatus of the sterile male anatomical models and sterile surgical gloves of an operator were inoculated with a high level of microorganisms (107 and 109 colony-forming units [CFU], respectively). The operator then performed catheterization of the anatomical model. The most relevant segments of the catheter were sampled, and the level of microbial transfer and catheter contamination was quantified. Results from experimental and sample replicates from the 3 microbial species and 5 catheters (sleeved and unsleeved) were analyzed by pair-wise t tests and analysis of variance.

RESULTS

Of the 5 commercially available sleeved intermittent catheters evaluated in this study, use of catheters with multiple protective components (ring cap, introducer tip, and catheter sleeve) resulted in significant improvement in protection against contamination with a 25- to 2500-fold lower level of microbial contamination (C1 segment) across all species as compared to catheters protected with only sleeves or un-sleeved catheters.

CONCLUSIONS

The combination of a ring cap, protective introducer tip, and protective sleeve provides additional protection when compared to sleeve alone from transferring microbial contamination from the meatus to the advancing catheter. Additional research is needed to determine whether these design features result in fewer urinary tract infections among intermittent catheter users.

Urinary Tract Infection in Children: A Narrative Review

This study investigates the susceptibility of different age groups and genders to urinary tract infections (UTIs) in pediatric populations, focusing on anatomical and behavioural factors. A systematic review of clinical data explores manifestations, accurate diagnosis methods, and antibiotic treatment regimens. Escherichia coli is a prevalent uropathogen, and the study addresses concerns about antibiotic resistance. The research aims to close knowledge gaps, influence guidelines, and enhance public health initiatives. Factors influencing UTI prevalence, such as age, gender, and structural abnormalities, are discussed. The review follows a robust search methodology, presenting a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram. The included studies cover a wide range of topics related to pediatric UTIs, including aetiology, treatment, prevention, and diagnostic approaches. The study emphasizes the importance of understanding and addressing pediatric UTIs for effective management and prevention.

Development and validation of artificial intelligence models to predict urinary tract infections and secondary bloodstream infections in adult patients

BACKGROUND

Traditional culture methods are time-consuming, making it difficult to utilize the results in the early stage of urinary tract infection (UTI) management, and automated urinalyses alone show insufficient performance for diagnosing UTIs. Several models have been proposed to predict urine culture positivity based on urinalysis. However, most of them have not been externally validated or consisted solely of urinalysis data obtained using one specific commercial analyzer.

METHODS

A total of 259,187 patients were enrolled to develop artificial intelligence (AI) models. AI models were developed and validated for the diagnosis of UTI and urinary tract related-bloodstream infection (UT-BSI). The predictive performance of conventional urinalysis and AI algorithms were assessed by the areas under the receiver operating characteristic curve (AUROC). We also visualized feature importance rankings as Shapley additive explanation bar plots.

RESULTS

In the two cohorts, the positive rates of urine culture tests were 25.2% and 30.4%, and the proportions of cases classified as UT-BSI were 1.8% and 1.6%. As a result of predicting UTI from the automated urinalysis, the AUROC were 0.745 (0.743-0.746) and 0.740 (0.737-0.743), and most AI algorithms presented excellent discriminant performance (AUROC > 0.9). In the external validation dataset, the XGBoost model achieved the best values in predicting both UTI (AUROC 0.967 [0.966-0.968]) and UT-BSI (AUROC 0.955 [0.951-0.959]). A reduced model using ten parameters was also derived.

CONCLUSIONS

We found that AI models can improve the early prediction of urine culture positivity and UT-BSI by combining automated urinalysis with other clinical information. Clinical utilization of the model can reduce the risk of delayed antimicrobial therapy in patients with nonspecific symptoms of UTI and classify patients with UT-BSI who require further treatment and close monitoring.

Uropathogenic Escherichia coli wield enterobactin-derived catabolites as siderophores

Uropathogenic Escherichia coli (UPEC) secrete multiple siderophore types to scavenge extracellular iron(III) ions during clinical urinary tract infections, despite the metabolic costs of biosynthesis. Here, we find the siderophore enterobactin (Ent) and its related products to be prominent components of the iron-responsive extracellular metabolome of a model UPEC strain. Using defined Ent biosynthesis and import mutants, we identify lower molecular weight dimeric exometabolites as products of incomplete siderophore catabolism, rather than prematurely released biosynthetic intermediates. In E. coli, iron acquisition from iron(III)-Ent complexes requires intracellular esterases that hydrolyze the siderophore. Although UPEC are equipped to consume the products of completely hydrolyzed Ent, we find that Ent and its derivatives may be incompletely hydrolyzed to yield products with retained siderophore activity. These results are consistent with catabolic inefficiency as means to obtain more than one iron ion per siderophore molecule. This is compatible with an evolved UPEC strategy to maximize the nutritional returns from metabolic investments in siderophore biosynthesis.

Therapeutic Effects of IL-1RA against Acute Bacterial Infections, including Antibiotic-Resistant Strains

Innate immunity is essential for the anti-microbial defense, but excessive immune activation may cause severe disease. In this study, immunotherapy was shown to prevent excessive innate immune activation and restore the anti-bacterial defense. E. coli-infected Asc-/- mice develop severe acute cystitis, defined by IL-1 hyper-activation, high bacterial counts, and extensive tissue pathology. Here, the interleukin-1 receptor antagonist (IL-1RA), which inhibits IL-1 hyper-activation in acute cystitis, was identified as a more potent inhibitor of inflammation and NK1R- and substance P-dependent pain than cefotaxime. Furthermore, IL-1RA treatment inhibited the excessive innate immune activation in the kidneys of infected Irf3-/- mice and restored tissue integrity. Unexpectedly, IL-1RA also accelerated bacterial clearance from infected bladders and kidneys, including antibiotic-resistant E. coli, where cefotaxime treatment was inefficient. The results suggest that by targeting the IL-1 response, control of the innate immune response to infection may be regained, with highly favorable treatment outcomes, including infections caused by antibiotic-resistant strains.

Genotypic Characterization of Uropathogenic Escherichia coli from Companion Animals: Predominance of ST372 in Dogs and Human-Related ST73 in Cats

Extraintestinal pathogenic Escherichia coli (ExPEC) account for over 80% and 60% of bacterial urinary tract infections (UTIs) in humans and animals, respectively. As shared uropathogenic E. coli (UPEC) strains have been previously reported among humans and pets, our study aimed to characterize E. coli lineages among UTI isolates from dogs and cats and to assess their overlaps with human UPEC lineages. We analysed 315 non-duplicate E. coli isolates from the UT of dogs (198) and cats (117) collected in central Germany in 2019 and 2020 utilizing whole genome sequencing and in silico methods. Phylogroup B2 (77.8%), dog-associated sequence type (ST) 372 (18.1%), and human-associated ST73 (16.6%), were predominant. Other STs included ST12 (8.6%), ST141 (5.1%), ST127 (4.8%), and ST131 (3.5%). Among these, 58.4% were assigned to the ExPEC group and 51.1% to the UPEC group based on their virulence associated gene (VAG) profile (ExPEC, presence of ≥VAGs: papAH and/or papC, sfa/focG, afaD/draBC, kpsMTII, and iutA; UPEC, additionally cnf1 or hlyD). Extended-spectrum cephalosporin (ESC) resistance mediated by extended-spectrum β-lactamases (ESBL) and AmpC-β-lactamase was identified in 1.9% of the isolates, along with one carbapenemase-producing isolate and one isolate carrying a mcr gene. Low occurrence of ESC-resistant or multidrug-resistant (MDR) isolates (2.9%) in the two most frequently detected STs implies that E. coli isolated from UTIs of companion animals are to a lesser extent associated with resistance, but possess virulence-associated genes enabling efficient UT colonization and carriage. Detection of human-related pandemic lineages suggests interspecies transmission and underscores the importance of monitoring companion animals.

A Hypothetical Approach to Concentrate Microorganisms from Human Urine Samples Using Paper-Based Adsorbents for Point-of-Care Molecular Assays

This hypothesis demonstrates that the efficiency of loop-mediated isothermal amplification (LAMP) for nucleic acid detection can be positively influenced by the preconcentration of microbial cells onto hydrophobic paper surfaces. The mechanism of this model is based on the high affinity of microbes towards hydrophobic surfaces. Extensive studies have demonstrated that hydrophobic surfaces exhibit enhanced bacterial and fungal adhesion. By exploiting this inherent affinity of hydrophobic paper substrates, the preconcentration approach enables the adherence of a greater number of target cells, resulting in a higher concentration of target templates for amplification directly from urine samples. In contrast to conventional methods, which often involve complex procedures, this approach offers a simpler, cost-effective, and user-friendly alternative. Moreover, the integration of cell adhesion, LAMP amplification, and signal readout within paper origami-based devices can provide a portable, robust, and highly efficient platform for rapid nucleic acid detection. This innovative hypothesis holds significant potential for point-of-care (POC) diagnostics and field surveillance applications. Further research and development in this field will advance the implementation of this technology, contributing to improved healthcare systems and public health outcomes.

Uropathogens and their antimicrobial-resistant pattern among suspected urinary tract infections patients in eastern Nepal: A hospital inpatients-based study

Background

Urinary tract infections are the primary factors that cause mortality and morbidity in patients with underlying comorbid conditions and are responsible for most hospital admissions worldwide.

Objectives

The study aims to identify the common bacterial uropathogens and determine their antimicrobial susceptibility pattern, including multidrug-resistant/extensively drug-resistant bacteria.

Methods

The descriptive cross-sectional study was conducted among inpatients provisionally suspected of urinary tract infections in the medical ward of Koshi Hospital, Biratnagar, Nepal. Samples were inoculated in a cystine lysine electrolyte-deficient medium, and pure growth of significant bacteria was further subjected Gram staining, biochemical identification, and antimicrobial susceptibility testing as per laboratory standard procedure and Clinical Laboratory Standards Institute guidelines, respectively. Descriptive and inferential statistical analysis was performed to analyze the outcomes and a p-value < 0.05 was considered statistically significant.

Results

A total of 305 patients urine specimens were examined, of which 251 (82.29%) samples resulted in significant bacterial growth in the culture. Escherichia coli (62.94%) was the most predominantly isolated organism, followed by Klebsiella pneumoniae (12.35%), Staphylococcus aureus (9.16%), and Pseudomonas aeruginosa (8.76%). Among antimicrobials, colistin had shown absolute susceptibility (100%) toward gram-negative uropathogens followed by carbapenem and aminoglycosides in a majority of uropathogens. Escherichia coli was found to be the leading drug-resistant bacteria (70%) among uropathogens. The presence of multidrug-resistant/extensively drug-resistant bacteria uropathogens was found to be significantly associated with diabetes mellitus and those with combined antimicrobial therapies. Diabetic patients were twice (OR~2) more likely to colonize and develop uropathogens as compared to non-diabetics.

Conclusion

Escherichia coli was the most common uropathogens followed by Klebsiella pneumoniae in urinary tract infection patients. The polymyxin group (colistin) of antimicrobials was found to be effective in all multidrug-resistant and extensively drug-resistant uropathogens. The study recommends the need of optimized antimicrobial stewardship program to develop effective strategies in the management of urinary tract infections in diverse healthcare settings.

Structure-activity relationship of drug conjugated polymeric materials against uropathogenic bacteria colonization under in vitro and in vivo settings

The human world has been plagued with different kinds of bacterial infections from time immemorial. The increased development of resistance towards commercial antibiotics has made these bacterial infections an even more critical challenge. Bacteria have modified their mode of interactions with different types of commercial drugs by bringing changes to the receptor proteins or by other resisting mechanisms like drug efflux. Various chemical approaches have been made to date to fight against these smart adapting species. Towards this, we hypothesize chemically modifying the commercial antibacterial drugs in order to deceive the bacteria and destroy the bacterial biomass. In this study, different molecular weight polyethyleneimines are taken and conjugated with some well-known commercial drugs like penicillin and chloramphenicol to explore their antibacterial properties against some of the laboratory and uro-pathogenic strains of Gram-positive and Gram-negative bacteria. A detailed structure-activity relationship of these polymeric prodrug-like materials has been evaluated to determine the optimum formulation. The standardized system not only shows significant ∼90% bacterial killing in liquid broth culture, but also demonstrates promising bacterial inhibition towards biofilm formation for the pathogenic strains on inanimate surfaces like urinary catheters and on an in vivo mouse skin abrasion model. The reported bioactive polymeric materials can be successfully used for widespread therapeutic applications with promising medical relevance.

Substances Secreted by Lactobacillus spp. from the Urinary Tract Microbiota Play a Protective Role against Proteus mirabilis Infections and Their Complications

Proteus mirabilis urinary tract infections can lead to serious complications such as development of urinary stones. Lactobacillus spp., belonging to the natural microbiota of the urinary tract, exhibit a number of antagonistic mechanisms against uropathogens, including the secretion of organic acids. In this study, we determined the anti-adhesion, anti-cytotoxicity and anti-crystallization properties of the substances secreted by Lactobacillus. For this purpose, membrane inserts with a pore diameter 0.4 μm were used, which prevent mixing of cultured cells, simultaneously enabling the diffusion of metabolic products. The intensity of crystallization was assessed by measuring the levels of Ca2+, Mg2+ and NH3 and by observing crystals using microscopic methods. The cytotoxicity of the HCV-29 cell line was determined using the LDH and MTT assays, and the impact of lactobacilli on P. mirabilis adhesion to the bladder epithelium was assessed by establishing CFU/mL after cell lysis. It was shown that in the presence of L. gasseri the adhesion of P. mirabilis and the cytotoxicity of the cells decreased. The degree of crystallization was also inhibited in all experimental models. Moreover, it was demonstrated that L. gasseri is characterized by the secretion of a high concentration of L-lactic acid. These results indicate that L-lactic acid secreted by L. gasseri has a significant impact on the crystallization process and pathogenicity of P. mirabilis.

Genetic and functional enrichments associated with Enterococcus faecalis isolated from the urinary tract

IMPORTANCE

Urinary tract infection (UTI) is a global health issue that imposes a substantial burden on healthcare systems. Women are disproportionately affected by UTI, with >60% of women experiencing at least one UTI in their lifetime. UTIs can recur, particularly in postmenopausal women, leading to diminished quality of life and potentially life-threatening complications. Understanding how pathogens colonize and survive in the urinary tract is necessary to identify new therapeutic targets that are urgently needed due to rising rates of antimicrobial resistance. How Enterococcus faecalis, a bacterium commonly associated with UTI, adapts to the urinary tract remains understudied. Here, we generated a collection of high-quality closed genome assemblies of clinical urinary E. faecalis isolated from the urine of postmenopausal women that we used alongside detailed clinical metadata to perform a robust comparative genomic investigation of genetic factors that may be involved in E. faecalis survival in the urinary tract.