Agent Of Urinary Tract Infections Research Articles

Mimicking Urinary Tract Infections Caused by Uropathogenic Escherichia coli Using a Human Three-Dimensional Tissue Engineering Model

Uropathogenic Escherichia coli are the main causal agent of urinary tract infections. These diseases can affect more than half of women during their lifetime. Moreover, recurrent urinary tract infections can affect up to 30% of patients, leading to higher social and economic costs for the community. No efficient treatment against the recurrent form of the disease has been discovered. Due to the low average rate of successful translation from 2D cell culture and in vivo animal models into clinical trials, new models that mimic pathologies, such as those produced by tissue engineering, are needed. A model of human-derived 3D bladder mucosa was produced by tissue engineering techniques using collagen gels and organ-specific primary human stromal and epithelial cell populations. This model was used to mimic the different steps of a urinary tract infection: adhesion, invasion, intracellular bacterial community and quiescent intracellular reservoir formation and, finally, bacteria resurgence after umbrella cell exfoliation through chitosan exposure to mimic the recurrent infection. The uropathogenic strain UTI-89-GFP was used as infectious bacteria and BL-21-GFP strain as a control. Our model is unique and is the first step toward mimicking the different phases of a UTI in a human context.

Modern approach to the treatment of urinary tract infections during pregnancy

Urinary tract infections (UTIs) are an extremely common pathology among pregnant women and women in labor, the manifestation of which occurs during pregnancy. Physiological changes in a woman’s organism form an optimal background for infection or activation of the aggression of one’s own microbial environments – the microflora that colonizes the periurethral area and mostly belongs to the family of enterobacteria and staphylococci.Clinical manifestations of UTIs during pregnancy are extremely variable and do not always correspond to the usual course of the disease, which necessitates the search for modern approaches to diagnosis and treatment. Also, UTI is one of the leading factors that provoke severe pregnancy complications and can lead to adverse obstetric outcomes.The objective: to evaluate the effectiveness of the modern etiopathogenetic approach to the treatment of UTIs during pregnancy.Materials and methods. In the study, which began in 2022 and is ongoing, 1615 pregnant women at gestational ages 6-37 weeks with clinical manifestations of urinary tract infections (UTIs). This work presents the survey results of 615 pregnant women with UTIs at gestational ages from 20 to 28 weeks, both before and one month after treatment initiation. These women were monitored during their pregnancies in prenatal care clinics of municipal non-commercial enterprises across all regions of Ukraine. At the stage of prescribing treatment the examined women are divided into two groups. The main group included 374 pregnant women with established diagnoses of acute urethritis, acute cystitis, gestational pyelonephritis (GP) and asymptomatic bacteriuria (ABU), who have received antibacterial and uroseptic agents for treatment in accordance with current clinical guidelines in combination with a herbal uroantiseptic containing 120 mg of cranberry berry extract and 36 mg each of extracts of goldenseal, lovage root, rosemary, as well as auxiliary substances. The comparison group included 241 pregnant women with established diagnoses of acute urethritis, acute cystitis, GP and ABU, who were treated exclusively with antibacterial and uroseptic agents for UTIs manifestations.The effectiveness of treatment methods was evaluated on the basis of a developed questionnaire with information on the main symptoms characteristic of diseases of the urinary system, before and one month after the prescribed treatment.Results. On the background of addition to the main antibacterial and uroseptic therapy the herbal uroantiseptic, containing 120 mg of cranberry berry extract and 36 mg each of extracts of yarrow, lovage root, rosemary, as well as auxiliary substances already a month after the start of treatment, the absence of complaints was found in the majority of pregnant women in the main group, related:with frequent urination – 354 (94.6%) (comparison group – 208 (86.3%); p<0.05), the need for urgent urination – 374 (99.1%) (comparison group – 232 (96.3%); p<0.05), the feeling of incomplete emptying of the bladder – 348 (93.3%) (comparison group – 202 (83.9%); p<0.05),with pain: during urination – 369 (98.7%) (comparison group – 231 (95.9%); p<0.05), in the lower abdomen, not associated with urination – 366 (97.9%) (comparison group – 230 (95.9%); p<0.05), in the lower back – 369 (98.7%) (comparison group – 229 (95.1%); p<0.05),with discharge from the urethra not related to urination – 374 (100.0%) (comparison group – 233 (96.7%); p<0.05).Conclusions. On the background of the prescribing of a herbal uroantiseptic containing 120 mg of cranberry extract and 36 mg of extracts of yarrow, lovage root, and rosemary, as well as auxiliary substances, additionally to the main antibacterial and uroseptic therapy in pregnant women of the main group, in a significantly greater number of cases the absence of complaints, which are associated with manifestations of urinary tract infections, was determined.The use of the herbal uroantiseptic, containing 120 mg of cranberry berry extract and 36 mg of extracts of yarrow, lovage root, and rosemary, is safe and creates favorable conditions for the course of pregnancy and further childbirth due to the potentiation of the effects of antibacterial and uroseptic therapy and the effective prevention of recurrences of urinary tract infections.

Draft genome of three uropathogenic Escherichia coli strains.

Uropathogenic Escherichia coli (UPEC) remains the main etiological agent of urinary tract infections affecting females and males. The draft genome sequence of three strains of UPEC isolated from senior citizens and pregnant women in the state of Puebla, Mexico, is reported here.

Efficacy of Nitrofurantoin and Fosfomycin against Extended Spectrum Beta Lactamase Producing Uropathogens in the Era of Antibiotic Resistance: A Cross-sectional Study

Background: Urinary Tract Infection (UTI) is one of the most common bacterial infections that require medical care. It accounts for 25% of all infections. Limited number of antibiotics are available for the treatment of UTI due to increased resistance among uropathogens. Aim of the study is to determine the causative agents of UTI and to evaluate the action of nitrofurantoin and fosfomycin against Enterobacteriaceae in ESBL (Extended spectrum beta-lactamase) producing strains. Material and Methods: It is a retrospective study carried out in the department of Microbiology, MAMC, Agroha. Data related to urine culture and antibiotic susceptibility pattern from January 2023 to December 2023 was taken from the records and analysed. Results: Out of 1648 urine samples processed, 569 showed significant bacterial growth. Escherichia coli (45.3%) was the most common isolate followed by Klebsiella pneumoniae (20.5%), Enterococcus (17.2%), Staphylococcus aureus (5%). Among the gram negative bacilli, 40% were ESBL producers. These ESBL producing strains were 99% sensitive to Fosfomycin and 75% sensitive to Nitrofurantoin. Conclusion: The study revealed that Nitrofurantoin and Fosfomycin are very effective oral drugs for empirical treatment against gram negative uropathogens causing UTI, especially multi drug resistant strains.

Microbiological profile and antimicrobial susceptibility of bacteria associated with urinary tract infections in Ukrainian adults

The aim of the study was to analyse the microbial profile of the urinary tract infections (UTIs) due to urolithiases and to study susceptibility to antibiotics in its causative agents. The main method of the research was bacteriological. Antimicrobial susceptibility testing was conducted by serial microdilution assay in accordance with recommendations of the European committee on antimicrobial susceptibility testing (EUCAST). For present study 128 unique urine samples were collected from patients with UTIs associated with urolithiasis. Among all collected specimens, 78% (n=100) gave clinically signi­ficant growth. Among all examined participants, 88.9% of women (64/72) and 64.3% of men (36/56) had confirmed UTI; in the study, female/male ratio was 1.4 (χ2=9.76; p<0.05). Microorganisms identified in our study predominantly belon­ged to Bacteria (93.4%), and yeasts of Candida genus comprised only 6.6%. Among all, 66.1% were representatives of Enterobacterales (n=80), particularly, Escherichia coli (38.0%), Klebsiella oxytoca (15.7%), Klebsiella pneumoniae (2.5%), Enterobacter cloacae (5.8%), Proteus mirabilis (4.1%). Isolates of Pseudomonas aeruginosa comprised 3.3%. Among gram-positive isolates, Staphylococcus spp. (14.1%) and Enterococcus spp. (9.9%) were identified. Regarding female/male distribution, the biggest proportion of gram-positive bacteria were isolated from women, statistically significant results were obtained for sex distribution of S. saprophyticus (p<0.05). Antimicrobial susceptibility of Enterobacterales was variable, and the best results were obtained for carbapenems, novel antibiotics (cefiderocol, ceftolozane-tazobactam and ceftazidime-avibactam), aminoglycosides and tigecycline. There were 9 isolates with pro­duction of carbapenemases and resistant to all relevant β-lactam antibiotics. All isolated Staphylococcus spp. were β-lactamase producers, one isolate of S. saprophyticus demonstrated methicillin-resistance. To summarise, there is an ongoing outbreak of multidrug-resistant infections in Ukraine and causative agents of UTIs are among the most important contributors. Availability of data on the local antimicrobial susceptibility profile may guide the informed decision making in etiotropic treatment, therefore, contribute to global efforts in rational drug use and fight the resistance escalation.

EVALUATION OF PATIENTS WITH COMPLICATED URINARY TRACT INFECTIONS: A SINGLE CENTRE EXPERIENCE

Aim: Urinary tract infection (UTI) is one of the most common infectious diseases and broad-spectrum antibiotics are commonly used for its treatment. Increased use of these antibiotics is leading to a rapid increase in antibiotic resistance rates in the treatment of UTI. In this study, we aimed to determine the causative agents and antibiotic resistance profile of these agents in patients with complicated UTIs. Material – Methods:We retrospectively evaluated the inpatients with complicated UTI in our clinic within one year. Results: The study included 154 patients (69 (44.8%) were male, 85 (55.2%) were female with a mean age of 68.9±15.3 years. The most common comorbidities were essential hypertension (n:87, 56.5%), type 2 diabetes mellitus (n:74, 48.1%), and cerebrovascular disease/coronary artery disease (n:49, 31.8%). The most common UTI agents were E.coli (46.1%), Klebsiella spp (14.9%), and Candida spp (7.1%). While 42.6% of these E.coli produced extended spectrum beta-lactamase (ESBL), 13% of Klebsiella spp produced ESBL. The frequency of ciprofloxacin resistance was statistically significantly higher in ESBL-positive bacteria compared to ESBL-negative bacteria (84.8%/35.9%, p

Identification of a copper-responsive small molecule inhibitor of uropathogenic Escherichia coli.

Urinary tract infections (UTIs) are a major global health problem and are caused predominantly by uropathogenic Escherichia coli (UPEC). UTIs are a leading cause of prescription antimicrobial use. Incessant increase in antimicrobial resistance in UPEC and other uropathogens poses a serious threat to the current treatment practices. Copper is an effector of nutritional immunity that impedes the growth of pathogens during infection. We hypothesized that copper would augment the toxicity of select small molecules against bacterial pathogens. We conducted a small molecule screening campaign with a library of 51,098 molecules to detect hits that inhibit a UPEC ΔtolC mutant in a copper-dependent manner. A molecule, denoted as E. coli inhibitor or ECIN, was identified as a copper-responsive inhibitor of wild-type UPEC strains. Our gene expression and metal content analysis results demonstrate that ECIN works in concert with copper to exacerbate Cu toxicity in UPEC. ECIN has a broad spectrum of activity against pathogens of medical and veterinary significance including Acinetobacter baumannii, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus. Subinhibitory levels of ECIN eliminate UPEC biofilm formation. Transcriptome analysis of UPEC treated with ECIN reveals induction of multiple stress response systems. Furthermore, we demonstrate that L-cysteine rescues the growth of UPEC exposed to ECIN. In summary, we report the identification and characterization of a novel copper-responsive small molecule inhibitor of UPEC.IMPORTANCEUrinary tract infection (UTI) is a ubiquitous infectious condition affecting millions of people annually. Uropathogenic Escherichia coli (UPEC) is the predominant etiological agent of UTI. However, UTIs are becoming increasingly difficult to resolve with antimicrobials due to increased antimicrobial resistance in UPEC and other uropathogens. Here, we report the identification and characterization of a novel copper-responsive small molecule inhibitor of UPEC. In addition to E. coli, this small molecule also inhibits pathogens of medical and veterinary significance including Acinetobacter baumannii, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus.

Characterization of bacteriophages infecting multidrug-resistant uropathogenic Escherichia coli strains

Uropathogenic Escherichia coli (UPEC) is the most common causative agent of urinary tract infections, and strains that are resistant to antibiotics are a major problem in treating these infections. Phage therapy is a promising alternative approach that can be used to treat infections caused by polyresistant bacterial strains. In the present study, 16 bacteriophages isolated from sewage and surface water were investigated. Phage host specificity was tested on a collection of 77 UPEC strains. The phages infected 2–44 strains, and 80% of the strains were infected by at least one phage. The susceptible E. coli strains belonged predominantly to the B2 phylogenetic group, including strains of two clones, CC131 and CC73, that have a worldwide distribution. All of the phages belonged to class Caudoviricetes and were identified as members of the families Straboviridae, Autographiviridae, and Drexlerviridae and the genera Kagunavirus, Justusliebigvirus, and Murrayvirus. A phage cocktail composed of six phages – four members of the family Straboviridae and two members of the family Autographiviridae – was prepared, and its antibacterial activity was tested in liquid medium. Complete suppression of bacterial growth was observed after 5–22 hours of cultivation, followed by partial regrowth. At 24 hours postinfection, the cocktail suppressed bacterial growth to 43–92% of control values. Similar results were obtained when testing the activity of the phage cocktail in LB and in artificial urine medium. The results indicate that our phage cocktail has potential to inhibit bacterial growth during infection, and they will therefore be preserved in the national phage bank, serving as valuable resources for therapeutic applications.

Competitive fitness of asymptomatic bacteriuria E. coli strain 83972 against uropathogens in human urine.

Urinary tract infection (UTI) is one of the most common bacterial infections worldwide. The main causative agent of UTI is uropathogenic Escherichia coli (UPEC). There is an immediate need for novel prophylactic and treatment strategies against UTI because of the increasing incidence of antimicrobial resistance among uropathogens. ABU 83972, an asymptomatic bacteriuria-causing E. coli strain, prevents UTI by suppressing the colonization of UPEC. However, the nature of competition and growth repression of UPEC by ABU 83972 is unclear and is the subject of our investigation. Here, we characterized the growth kinetics of ABU 83972 and uropathogens in human urine and laboratory media. Next, we performed a series of competitive co-culture experiments where ABU 83972 and uropathogens were inoculated at a 1:1 ratio in human urine and in various media, and their relative abundance was determined. In human urine, ABU 83972 outcompeted UPEC and additional uropathogens, reaching up to 90% of the total population after 24 hours of incubation. In contrast, UPEC outcompeted ABU 83972 in LB and M9 minimal media and exhibited superior colonization than ABU 83972 in the mouse urinary bladder. Since engineered living materials (ELMs) can be used to retain an organism of interest in a particular location, we developed ABU 83972-containing ELMs that effectively outcompeted UPEC in human urine. In summary, our work establishes that ABU 83972 outcompetes UPEC in a milieu- and cell-density-dependent manner, highlighting the importance of the metabolites and nutrients found in the human urine as determinants of the competitive fitness of ABU 83972.

Gentamicin loaded niosomes against intracellular uropathogenic Escherichia coli strains

Urinary tract infections (UTIs) are the most common bacterial infections and uropathogenic Escherichia coli (UPEC) is the main etiological agent of UTIs. UPEC can persist in bladder cells protected by immunological defenses and antibiotics and intracellular behavior leads to difficulty in eradicating the infection. The aim of this paper is to design, prepare and characterize surfactant-based nanocarriers (niosomes) able to entrap antimicrobial drug and potentially to delivery and release antibiotics into UPEC-infected cells. In order to validate the proposed drug delivery system, gentamicin, was chosen as “active model drug” due to its poor cellular penetration. The niosomes physical–chemical characterization was performed combining different techniques: Dynamic Light Scattering Fluorescence Spectroscopy, Transmission Electron Microscopy. Empty and loaded niosomes were characterized in terms of size, ζ-potential, bilayer features and stability. Moreover, Gentamicin entrapped amount was evaluated, and the release study was also carried out. In addition, the effect of empty and loaded niosomes was studied on the invasion ability of UPEC strains in T24 bladder cell monolayers by Gentamicin Protection Assay and Confocal Microscopy. The observed decrease in UPEC invasion rate leads us to hypothesize a release of antibiotic from niosomes inside the cells. The optimization of the proposed drug delivery system could represent a promising strategy to significatively enhance the internalization of antimicrobial drugs.

High prevalence of plasmid-mediated quinolone resistance in escherichia coli strains producing extended-spectrum beta-lactamases isolated from faeces and urine of pregnant women with acute cystitis.

Escherichia coli is the most common etiological agent of urinary tract infections (UTIs). Meanwhile, plasmid-mediated quinolone resistance (PMQR) is reported in E. coli isolates producing extended-spectrum β-lactamases (ESBLs). Furthermore, the reservoirs and mechanisms of acquisition of uropathogenic Escherichia coli (UPEC) strains are poorly understood. On the other hand, UTIs are common in pregnant women and the treatment challenge is alarming. In the present study, 54 pregnant women with acute cystitis were included. A total of 108 E. coli isolates, 54 isolates from UTI and 54 isolates from faeces of pregnant women (same host) were collected. In the antimicrobial susceptibility test, the highest rate of antibiotic resistance was to nalidixic acid (77%, 83/108) and the lowest rate was to imipenem (9%, 10/108). Among the isolates, 44% (48/108) were ESBLs producers. A high frequency of PMQR genes was observed in the isolates. The frequency of PMQR genes qnrS, qnrB, aac(6')-Ib-cr, and qnrA was 58% (63/108), 21% (23/108), 9% (10/108), and 4% (4/108), respectively. Meanwhile, PMQR genes were not detected in 24% (20/85) of isolates resistant to nalidixic acid and/or fluoroquinolone, indicating that other mechanisms, i.e. chromosomal mutations, are involved in resistance to quinolones, which were not detected in the present study. In ESBL-producing isolates, the frequency of PMQR genes was higher than that of non-ESBL-producing isolates (81% vs. 53%). Meanwhile, UTI and faeces isolates mainly belonged to phylogenetic group B2 (36/54, 67% and 25/54, 46%, respectively) compared to other phylogenetic groups. In addition, virulence factors and multidrug-resistant (MDR) were mainly associated with phylogenetic group B2. However, predominant clones in faeces were not found in UTIs. Rep-PCR revealed the presence of 85 clones in patients. Among the clones, 40 clones were detected only in faeces (faeces-only), 35 clones only in UTI (UTI-only) and 10 clones in both faeces and UTI (faeces-UTI). We found that out of 10 faeces-UTI clones, 5 clones were present in the host's faeces flora. This study revealed a high rate of resistance to the quinolone nalidixic acid and a widespread distribution of PMQR genes in MDR E. coli strains producing ESBLs. The strains represented virulence factors and phylogenetic group B2 are closely associated with abundance in UTI and faeces. However, the predominant clones in faeces were not found in UTIs and it is possible that rep-PCR is not sufficiently discriminating clones.

Nucleoside-diphosphate kinase of uropathogenic Escherichia coli inhibits caspase-1-dependent pyroptosis facilitating urinary tract infection

Uropathogenic Escherichia coli (UPEC) is the most common causative agent of urinary tract infection (UTI). UPEC invades bladder epithelial cells (BECs) via fusiform vesicles, escapes into the cytosol, and establishes biofilm-like intracellular bacterial communities (IBCs). Nucleoside-diphosphate kinase (NDK) is secreted by pathogenic bacteria to enhance virulence. However, whether NDK is involved in UPEC pathogenesis remains unclear. Here, we find that the lack of ndk impairs the colonization of UPEC CFT073 in mouse bladders and kidneys owing to the impaired ability of UPEC to form IBCs. Furthermore, we demonstrate that NDK inhibits caspase-1-dependent pyroptosis by consuming extracellular ATP, preventing superficial BEC exfoliation, and promoting IBC formation. UPEC utilizes the reactive oxygen species (ROS) sensor OxyR to indirectly activate the regulator integration host factor, which then directly activates ndk expression in response to intracellular ROS. Here, we reveal a signaling transduction pathway that UPEC employs to inhibit superficial BEC exfoliation, thus facilitating acute UTI.

Causative Agents and their Antimicrobial Susceptibilities of Catheter-related Urinary Tract Infection among Spinal Cord Injury or Disorder Patients

Abstract Background and Objectives: Complicated urinary tract infections (UTIs) are often difficult to treat because of the existence of isolated antibiotic-resistant strains. Impaired bladder emptying is present in around 60% of spinal cord injuries or disorders patients. The objective of the study was to find the causative agents and their antimicrobial susceptibilities of catheter-related UTIs. Methods: The study was conducted among 160 subjects from Calicut District, Kerala, India using the purposive sampling method. From this, 89 were using intermittent and 71 were using indwelling catheterization. UTI was assessed by urine culture and sensitivity test from NABL accredited laboratory. Statistical Analysis Used: The association between demographic and clinical variables was performed using the Chi-square test. P < 0.05 was considered statistically significant. Results: The study consisted of 160 spinal cord injuries or disorders patients with a mean age at which injury occurred was 35.66 ± 12.78. For the detection of UTIs, culture and sensitivity of urine were done. Out of them, 115 (72%) had UTIs. Escherichia coli was the most common causative agent of UTI 55 (47.8%), followed by Klebsiella 33 (28.6%), Pseudomonas 9 (7.8%), and Proteus vulgaris 7 (6.3%). The study showed that the most resistant antimicrobial agents for E. coli were ampicillin 39 (71%), amoxicillin and potassium clavulanate 32 (58%), and cefuroxime oral. Less resistant antimicrobial agents to E. coli were doxycycline 12 (21%), cefepime 13 (24%), and gentamicin 16 (29%). The most resistant antimicrobial agents to Klebsiella were ampicillin 33 (100%) and nitrofurantoin 23 (70%). Conclusion: UTI is one of the most common complications among spinal cord injuries or disorders patients using a catheter for bladder emptying. Appropriate antibiotics should be prescribed to treat UTIs and to avoid antimicrobial resistance.

The inner membrane protein YhiM links copper and CpxAR envelope stress responses in uropathogenic E. coli.

Urinary tract infection (UTI) is a ubiquitous infectious condition, and uropathogenic Escherichia coli (UPEC) is the predominant causative agent of UTI. Copper (Cu) is implicated in innate immunity, including against UPEC. Cu is a trace element utilized as a co-factor, but excess Cu is toxic due to mismetalation of non-cognate proteins. E. coli precisely regulates Cu homeostasis via efflux systems. However, Cu import mechanisms into the bacterial cell are not clear. We hypothesized that Cu import defective mutants would exhibit increased resistance to Cu. This hypothesis was tested in a forward genetic screen with transposon (Tn5) insertion mutants in UPEC strain CFT073, and we identified 32 unique Cu-resistant mutants. Transposon and defined mutants lacking yhiM, which encodes a hypothetical inner membrane protein, were more resistant to Cu than parental strain. Loss of YhiM led to decreased cellular Cu content and increased expression of copA, encoding a Cu efflux pump. The CpxAR envelope stress response system was activated in the ΔyhiM mutant as indicated by increased expression of cpxP. Transcription of yhiM was regulated by CueR and CpxR, and the CpxAR system was essential for increased Cu resistance in the ΔyhiM mutant. Importantly, activation of CpxAR system in the ΔyhiM mutant was independent of NlpE, a known activator of this system. YhiM was required for optimal fitness of UPEC in a mouse model of UTI. Our findings demonstrate that YhiM is a critical mediator of Cu homeostasis and links bacterial adaptation to Cu stress with the CpxAR-dependent envelope stress response in UPEC.IMPORTANCEUPEC is a common bacterial infection. Bacterial pathogens are exposed to host-derived Cu during infection, including UTI. Here, we describe detection of genes involved in Cu homeostasis in UPEC. A UPEC mutant lacking YhiM, a membrane protein, exhibited dramatic increase in resistance to Cu. Our study demonstrates YhiM as a nexus between Cu stress and the CpxAR-dependent envelope stress response system. Importantly, our findings establish NlpE-independent activation of CpxAR system during Cu stress in UPEC. Collectively, YhiM emerges as a critical mediator of Cu homeostasis in UPEC and highlights the interlinked nature of bacterial adaptation to survival during Cu and envelope stress.

Prevalence of bacterial isolates and change in their antibiotic susceptibility patterns in urinary tract infections- A five year retrospective study

Urinary Tract Infection (UTI) continues to be one of the commonly occurring infections in medical practice despite the widespread availability of antibiotics. Presence of risk factors like elderly age, diabetes, immune-suppression, and other comorbidity pose a challenge in its treatment. Over the years, the etiology and antibiotic resistance of the uropathogens has been inconsistent. Therefore, it is important to determine the causative agents of UTI and their resistance patterns locally, in each region, so that appropriate empiric therapy can be started before the culture and antibiotic sensitivity results are available. This study aims to highlight the prevalence of uropathogens and determine the antibiotic sensitivity pattern over the period of five years.The urine samples from patients with suspected urinary tract infections (UTI) received in the laboratory at Nanavati Max Super speciality hospital were processed by standard protocol from January 2018 to December 2022. Antibiotic susceptibility test for the bacterial isolates was carried out by the VITEK2 automated system and interpreted as per CLSI guidelines. The data collected over the study period of five years was interpreted by using the WHO Net Antibiotic Susceptibility Surveillance Software in February 2023. From a total of 8068 urine samples received over five years, uropathogens were isolated in 4209 (52.16%) samples. E.coli was the most common isolate causing UTI, with prevalence of 380(46.7%) in 2018 and 480(50.6%) in 2022 of total samples. Amongst gram positive organisms, a rise in Enterococcus species was seen from 41(5%) in 2018 to 87(9%) in 2022, with significantly fewer Staphylococcus species isolated, from 32(4%) in 2018 to 7(0.7%) in 2022. The Enterobacteriaceae showed high sensitivity to Amikacin, Tigecycline and Meropenem all throughout the study. However, rise in resistance to Nitrofurantoin and Fosfomycin, antibiotics commonly used for UTIs, was observed. Also the prevalence of Extended Spectrum of Beta lactamase (ESBL) producers decreased from 213(36%) to 127(17%) with a rise in Carbapenemase producing Enterobacteriaceae from 48(8%) to 298(40%) over the five years study period.Amongst Lactose Nonfermenting gram negative bacilli only 32 % were sensitive to Carbapenems and 37% sensitive to Aminoglycosides.By 2022, Enterococcus species showed an increase in sensitivity to Nitrofurantoin (27%), High level Aminoglycosides (37%), Fluoroquinolones (25%) and Ampicillin (37%).The change in antibiotic sensitivity patterns over time and rise in resistance to antibiotics commonly used in empirical treatment of UTIs warrants the need for regular surveillance, so the physicians can be updated regarding the most prevalent organism and its susceptibility and the empirical treatment for UTIs can be modified accordingly. This can help curb indiscriminate use of antibiotics and development of antibiotic resistance.

Exosomes derived from bladder epithelial cells infected with uropathogenic Escherichia coli increase the severity of urinary tract infections (UTIs) by impairing macrophage function.

Uropathogenic Escherichia coli (UPEC) is the primary causative agent of urinary tract infections (UTIs) in humans. Moreover, as one of the most common bacterial pathogens, UPEC imposes a substantial burden on healthcare systems worldwide. Epithelial cells and macrophages are two major components of the innate immune system, which play critical roles in defending the bladder against UPEC invasion. Yet, the routes of communication between these cells during UTI pathogenesis are still not fully understood. In the present study, we investigated the role of membrane-bound nanovesicles (exosomes) in the communication between bladder epithelial cells and macrophages during UPEC infection, using an array of techniques such as flow cytometry, miRNA profiling, RNA sequencing, and western blotting. Moreover, our in vitro findings were validated in a mouse model of UPEC-induced cystitis. We found that UPEC infection induced the bladder epithelial MB49 cell line to secrete large numbers of exosomes (MB49-U-Exo), which were efficiently absorbed by macrophages both in vivo and in vitro. Assimilation of MB49-U-Exo induced macrophages to produce proinflammatory cytokines, including tumor necrosis factor (TNF)α. Exposure of macrophages to MB49-U-Exo reduced their phagocytic activity (by downregulating the expression of phagocytosis-related genes) and increased their rate of apoptosis. Mechanistically, we showed that MB49-U-Exo were enriched in miR-18a-5p, which induced TNFα expression in macrophages by targeting PTEN and activating the MAPK/JNK signaling pathway. Moreover, administration of the exosome secretion inhibitor GW4869 or a TNFα-neutralizing antibody alleviated UPEC-mediated tissue damage in mice with UPEC-induced cystitis by reducing the bacterial burden of the bladder and dampening the associated inflammatory response. Collectively, these findings suggest that MB49-U-Exo regulate macrophage function in a way that exacerbates UPEC-mediated tissue impairment. Thus, targeting exosomal -release or TNFα signaling during UPEC infection may represent promising non-antibiotic strategies for treating UTIs.

Antimicrobial Potential of Probiotic Strains From Bulgarian Cheese and Shallot Yogurt Against Staphylococcus saprophyticus.

The escalating incidence of hospital infections due to antibiotic resistance necessitates the identification of alternative therapeutic agents such as probiotics. This study was designed to isolate and evaluate the efficacy of probiotics against Staphylococcus saprophyticus, a prevalent etiological agent of urinary tract infections (UTIs). A total of 100 S. saprophyticus strains were isolated from clinical samples and subjected to antibiotic susceptibility testing via the disc diffusion method. Concurrently, probiotic bacteria were isolated from Bulgarian cheese and shallot yogurt, and their antibacterial activity against S. saprophyticus strains was assessed. The inhibitory potential of probiotic supernatants was evaluated using microtiter plate assays, with the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) determined at a 1/2 dilution. Cytotoxicity was evaluated using the MTT assay, and high-performance liquid chromatography (HPLC) was employed to analyze the concentrations of organic acids produced by the probiotics. The results revealed that all S. saprophyticus strains were resistant to tetracycline and doxycycline but susceptible to other antibiotics. Lactobacillus rhamnosus strains M and B demonstrated notable antibacterial and antibiofilm activity against S. saprophyticus isolates. These probiotics exhibited susceptibility to most antibiotics and lacked virulence factors, suggesting their safety for therapeutic use. The organic acids produced by the probiotics were identified as lactic acid, acetic acid, and formic acid. In conclusion, L. rhamnosus strains M and B exhibit potent antimicrobial properties against S. saprophyticus, indicating their potential as therapeutic agents for UTIs. Further research is warranted to validate these findings and explore the possibility of these probiotics in clinical applications.

Fungal Endophytes - An Alternative Source of Bioactive Compounds from Plant Species for Prospective Applications – Review

Plant derived compounds have a strong antagonistic activity on pathogenic microorganisms using tremendous natural bioactive compounds accumulated in different parts of plants. Limonoids are important group of metabolically altered triterpene in Meliaceae. Out of 300 limonoids known today, Melia azedarach (melianone, meliarachin, meliacine), Melia dubia (nimbin, meliacarpin) and Azadirachta indica (azadirachtin, nimbolide) contributes about one-third of limonoids. Endophytic fungi are plant symbionts that act as an elicitor for the production of secondary metabolites which serves as an excellent source of drugs for various ailments. It has a great potential to synthesize several novel bioactive compounds which paved a way for commercial exploitation of secondary metabolites for pharmaceutical and agricultural sectors. Many dominant endophytic fungi isolated from these plants includes Colletotrichum sp, Trichoderma sp, Penicillium citrinum, Fusarium solani, Aspergillus sp, Nigrospora sp and Alternaria sp which acts on human pathogenic microorganisms such as Escherichia coli Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae and Candida albicans common causative agents for Urinary Tract Infections (UTI) predominantly occurring in women. This review aims to delineate the overview on sources of limonoids present in the leaves and the endophytic fungi isolated from these leaves of Meliaceae. The isolated endophytic fungi from the leaves exhibited antagonistic activity on UTI causing pathogens which often leads to infertility among young women. Thus, the sources of limonoids and isolation of endophytic fungi can be enhanced by reinforcing the production of commercial bioactive secondary metabolites that can be substantially utilized by pharmaceutical and agricultural industries to safeguard human beings.

Urinary tract infections in children with cancer and febrile neutropenia - single center experience

Background/Aim. Urinary tract infection (UTI) in children with febrile neutropenia (FN) after receiving chemotherapy could be followed by atypical symptoms and signs. The absence of routine urine culture (UC) sampling for analysis could lead to undiagnosed disease and inadequate treatment of these patients. The aim of the study was to indicate the importance of sampling UC in children who have developed FN and to point out the most probable causative agents of UTI in children with FN and antibiotic sensitivity/resistance of the isolated strains. Methods. During a five-year observation period, 40 UTIs were registered in 30 patients with FN. In the study group of patients with FN, the number of UTIs, the number of recurrent UTIs, isolated pathogens, their sensitivity to antibiotics, characteristics of urine sediment, the presence of localized symptoms of UTI, and the presence of urosepsis were analyzed. The obtained results were compared with the control group which consisted of children who were healthy prior to hospitalization due to febrile urinary infection. Results. When compared to the control group, significant differences in the presence of symptoms of UTI and urine sediment findings in patients with FN were observed. A higher percentage of resistant strains of Escherichia coli isolated from UC of cancer patients with FN was noted when compared to the control group. Three UTI cases were followed by urosepsis. Conclusion. UC findings are important not only in establishing the diagnosis of UTI and detecting multi-resistant bacterial strains but also in choosing appropriate antibiotics and selecting a subgroup of patients with recurrent UTI who require further monitoring and detecting potential complications in a timely manner.

Bacterial profile of urinary tract infection among pregnant women: a systematic review

Urinary tract infection (UTI) is the infection and colonization of microorganisms in the urinary tract. Women carry a higher risk of being affected by UTI compared to males, especially during pregnancy due to physiological and hormonal changes. Appropriate and adequate management of UTI reduces the incidence of further maternal and fetal complications. Nonetheless, there is a growing concern regarding resistance to antibiotics among the bacteria causing UTIs in pregnant women. To identify the bacterial profile of UTIs during gestation by exploring the previous research conducted on this subject. A systematic online search was performed on scientific databases to obtain articles related to the current subject using search terms, including bacteria, profile, causative agent, sensitivity, resistance, symptomatic, pregnancy, gestation, and pregnant women. The articles of relevance were considered if they were original articles, written in the English language, available for full-text, and reporting bacterial profile of UTI during pregnancy. A total of eight articles were eligible and met the inclusion criteria. The studies were published between 2020 and 2023 and included a total number of 3,702 pregnant females from five different countries. The bacterial profile of UTI among pregnant women including symptomatic UTI, and resistance and sensitivity of bacteria to antibiotics varied between different regions. However, the causative agents of UTI displayed less variation as Escherichia coli and K.pneomniae were the major causative agents of UTI during pregnancy.