Diagnosis of urinary tract infections in the hospitalized older adult population in Alberta.

BACKGROUND: Urinary tract infections (UTIs) are one of the most common infections reported in older adults, across all settings. Although a diagnosis of a UTI requires specific clinical and microbiological criteria, many older adults are diagnosed with a UTI without meeting the diagnostic criteria, resulting in unnecessary antibiotic treatment and their potential side effects, and a failure to find the true cause of their presentation to hospital. OBJECTIVE: The aim of this study was to evaluate the accuracy of UTI diagnoses amongst hospitalized older adults based on clinical and microbiological findings, and their corresponding antibiotic treatment (including complications), in addition to identifying possible factors associated with a confirmed UTI diagnosis. METHODS: A single-center retrospective cross-sectional study of older adult patients (n = 238) hospitalized at the University of Alberta Hospital with an admission diagnosis of UTI over a one-year period was performed. RESULTS: 44.6% (n = 106) of patients had a diagnosis of UTI which was supported by documents clinical and microbiological findings while 43.3% (n = 103) of patients had bacteriuria without documented symptoms. 54.2% (n = 129) of all patients were treated with antibiotics, despite not having evidence to support a diagnosis of a UTI, with 15.9% (n = 37) of those patients experiencing complications including diarrhea, Clostridioides difficile infection, and thrush. History of major neurocognitive disorder was significantly associated with diagnosis of UTI (p = 0.003). CONCLUSION: UTIs are commonly misdiagnosed in hospitalized older adults by healthcare providers, resulting in the majority of such patients receiving unnecessary antibiotics, increasing the risk of complications. These findings will allow for initiatives to educate clinicians on the importance of UTI diagnosis in an older adult population and appropriately prescribing antibiotics to prevent unwanted complications.

Association Between Sexually Transmitted Infections and the Urine Culture.

Introduction: Bacterial urinary tract infections (UTI) and some sexually transmitted infections (STI) can have overlapping signs and symptoms or nonspecific findings, such as pyuria on urinalysis. Furthermore, results from the urine culture and the nucleic acid amplification test for an STI may not be available during the clinical encounter. We sought to determine whether gonorrhea, chlamydia, and trichomoniasis are associated with bacteriuria, information that might aid in the differentiation of STIs and UTIs. Methods: We used multinomial logistic regression to analyze 9,650 encounters of female patients who were aged ≥18 years and who underwent testing for STIs. The ED encounters took place from April 18, 2014-March 7, 2017. We used a multivariable regression analysis to account for patient demographics, urinalysis findings, vaginal wet-mount results, and positive or negative (or no) findings from the urine culture and testing for Neisseria gonorrhoeae, Chlamydia trachomatis, or Trichomonas vaginalis. Results: In multivariable analysis, infection with T vaginalis, N gonorrhoeae, or C trachomatis was not associated with having a urine culture yielding 10,000 or more colony-forming units per mililiter (CFU/mL) of bacteria compared with a urine culture yielding less than 10,000 CFU/mL or no urine culture obtained. The diagnosis of a UTI in the ED was not associated with having a urine culture yielding 10,000 or more CFU/mL compared with a urine culture yielding less than 10,000 CFU/mL. Conclusion: After adjusting for covariates, no association was observed between urine culture results and testing positive for trichomoniasis, gonorrhea, or chlamydia. Our results suggest that having a concurrent STI and bacterial UTI is unlikely.

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.

Turbidimetric bioassays: A solution to antimicrobial activity detection in asymptomatic bacteriuria isolates against uropathogenic Escherichia coli.

Traditional bacteriocin screening methods often face limitations due to diffusion-related challenges in agar matrices, which can prevent the peptides from reaching their target organism. Turbidimetric techniques offer a solution to these issues, eliminating diffusion-related problems and providing an initial quantification of bacteriocin efficacy in producer organisms. This study involved screening the cell-free supernatant (CFS) from eight uncharacterized asymptomatic bacteriuria (ABU) isolates and Escherichia coli 83972 for antimicrobial activity against clinical uropathogenic E. coli (UPEC) strains using turbidimetric growth methods. ABU isolates exhibiting activity against five or more UPEC strains were further characterized (PUTS 37, PUTS 58, PUTS 59, S-07-4, and SK-106-1). The inhibition of the CFS by proteinase K suggested that the antimicrobial activity was proteinaceous in nature, potentially bacteriocins. The activity of E. coli PUTS 58 and SK-106-1 was enhanced in an artificial urine medium, with both inhibiting all eight UPECs. A putative microcin H47 operon was identified in E. coli SK-106-1, along with a previously identified microcin V and colicin E7 in E. coli PUTS 37 and PUTS 58, respectively. These findings indicate that ABU bacteriocin-producers could serve as viable prophylactics and therapeutics in the face of increasing antibiotic resistance among uropathogens.

Diagnostic Stewardship for Urine Cultures.

Urinary tract infections are among the most common infectious diagnoses in health care, but most urinary tract infections are diagnosed inappropriately in patients without signs or symptoms of infection. Asymptomatic bacteriuria leads to inappropriate antibiotic prescribing and negative downstream effects, including antimicrobial resistance, health care-associated infections, and adverse drug events. Diagnostic stewardship is the process of modifying the ordering, performing, or reporting of test results to improve clinical care. Diagnostic stewardship impacts the diagnostic pathway to decrease inappropriate detection and treatment of asymptomatic bacteriuria. This article reviews diagnostic stewardship methods and closes with a case study illustrating these principles in practice.

Bacteriological profile, antimicrobial susceptibility, and factors associated with urinary tract infection in pregnant women.

INTRODUCTION: Urinary tract infection (UTI) is a common bacterial complication in pregnancy. The study aimed to estimate the prevalence, risk factors, and bacterial etiology of UTI during pregnancy and determine the efficacy of antimicrobial drugs in treating UTIs. METHODOLOGY: Urine specimens and clinical data were collected from pregnant women who attended primary health centers in Erbil, Iraq. All specimens were cultured on appropriate media and identified by standard microbiological methods. The pregnant women were grouped into symptomatic UTI group, asymptomatic bacteriuria group, and the control group. The agar dilution method was used to determine antimicrobial susceptibility. RESULTS: Among the 5,042 pregnant women included in this study, significant bacteriuria was found in 625 (12.40%) of the cases, and 198 (31.68%) had symptomatic UTI, of which 43.59% were diagnosed during the third trimester. Out of the 643 bacteria isolated, 33.28% were symptomatic UTI, of which 43.59% developed during the third trimester. There was a significant difference in the bacterial etiology between symptomatic UTI and asymptomatic bacteriuria (p = 0.002), as well as between cystitis and pyelonephritis (p = 0.017). The most common bacterial species isolated was Escherichia coli, which was susceptible to fosfomycin (100%), meropenem (99.45%), and nitrofurantoin (97.8%). CONCLUSIONS: Pregnant women are more likely to develop UTI in the third trimester. Escherichia coli is the predominant pathogen. The study suggests the use of fosfomycin, meropenem, and nitrofurantoin for the treatment of UTI. No Gram-positive isolates were resistant to daptomycin.

Asymptomatic bacteriuria in patients with type 2 diabetes mellitus in rural southwestern Nigeria: a cross-sectional study.

OBJECTIVES: We aimed to identify the prevalence, bacterial isolates, antimicrobial susceptibility profile, and factors associated with asymptomatic bacteriuria (ASB) in patients with type 2 diabetes mellitus (T2DM) in rural southwestern Nigeria. METHODS: We performed a hospital-based cross-sectional study of patients with T2DM and ASB. Demographic and clinical data were collected using questionnaires. Urine samples were cultured using standard laboratory procedures, and bacterial colonies were isolated and antimicrobial sensitivity was performed using the disc diffusion technique. Relationships between variables were assessed using adjusted odds ratios (AORs) and 95% confidence intervals (CIs). RESULTS: Of the 280 participants, 73 (26.1%) had ASB (95% CI: 20.9%-31.2%). The most commonly identified isolate was E. coli (45/73; 61.7%), 100.0% of which were sensitive to cefuroxime but resistant to ciprofloxacin. Female sex (AOR, 6.132; 95% CI: 2.327-16.157), living below the poverty line (AOR, 2.066; 95% CI: 1.059-4.029), uncontrolled blood glucose (AOR, 2.097; 95% CI: 1.000-4.404), and a history of indwelling urethral catheterization (AOR, 14.521; 95% CI: 4.914-42.908) were associated with ASB. CONCLUSION: The findings suggest that cefuroxime should be used as an empirical treatment, pending urine culture and sensitivity, and that efforts should be made to prevent ASB in rural southwestern Nigeria.

Asymptomatic bacteriuria prior to partial and radical nephrectomy: To screen or not to screen? Results from the national and multicenter TOCUS database.

INTRODUCTION: In the era of increased bacterial resistance, the main strategy is to reduce the prescription of antibiotics when possible. Nowadays, it is highly recommended to screen for asymptomatic bacteriuria (ABU), prior to urological surgery with potential mucosal breach or urine exposure. Screening and treating urinary colonization is a strategy widely adopted before radical and partial nephrectomy but without any evidence. Our main end point in this study is to analyze the relationship between preoperative urine culture and the risk of postoperative febrile urinary tract infection (UTI) or surgical-site infection (SSI) in partial or radical nephrectomy patients. METHODS: We conducted a multicenter retrospective cohort study between January 2016 and January 2023 in 11 French tertiary referral hospitals (TOCUS database). We collected the data for 269 patients including several pre-, intra-, and post-operative variables that could potentially increase the risk of postoperative UTI and SSI including preoperative urinary culture results. RESULTS: The incidence rate of postoperative UTI and SSI was 8.9% in our study. After conducting a logistic multivariate analysis, a propensity score matching analysis, and a subgroup analysis, we found no significant correlation between the urine culture and the postoperative UTI risk [OR = 1.2 (0.5-2.7) (p = 0.7)]. Only the postoperative non-infectious complications were related to a higher risk of postoperative UTI [OR = 12 (4-37), p < 0.001)]. CONCLUSION: Our research shows that screening and treating for ABU prior to radical or partial nephrectomy seems to be unnecessary to prevent postoperative UTI and SSI.

Reviving Sternheimer stain: A single-center retrospective study to detect the diagnostic utility of urinary tract infections in the emergency department.

INTRODUCTION: Qualitative urinalysis using the Sternheimer stain is a common method in Japan for identifying bacteriuria, but there is a lack of studies examining its test characteristics. In this study, we aimed to investigate the sensitivity and specificity of the Sternheimer stain for urine culture results and compare it with the sensitivity and specificity of the Gram stain. Our goal was to determine the usefulness of the Sternheimer stain in identifying bacteriuria. PATIENTS AND METHODS: Among 986 patients aged 16 years or older from whom samples for both urinalysis and urine culture were obtained at the emergency room of Tenri Hospital from January 2019 to December 2019, 342 patients with pyuria, defined as the presence of 10 or more white cells per cubic millimeter in a urine specimen, who had not received prior antimicrobial therapy were included. Urine cultures were used for comparison to determine the sensitivity and specificity of Sternheimer and Gram stain in this patient group. A positive Sternheimer stain result was defined as bacteriuria ≥ (1+), and that of Gram stain was defined as ≥ 1/1 field of high-power ( × 1000) oil immersion. RESULTS: Using urine culture results for comparison, the sensitivity of Sternheimer stain was 92.2%, the specificity was 48.5%, the positive likelihood ratio was 1.79, and the negative likelihood ratio was 0.16. DISCUSSION: Sternheimer stain is a rapid and useful method to exclude bacteriuria in a group of patients with pyuria in the emergency department.

First trimester "clean catch" urine and vaginal swab sample distinct microbiological niches.

IMPORTANCE: Untreated asymptomatic bacteriuria (ASB) has been associated with adverse pregnancy outcomes, including pyelonephritis, preterm labor, and low birth weight infants. Thus, routine screening by standard urine culture (SUC) and treatment of ASB are currently recommended for all pregnant women. For this purpose, some researchers claim that vaginal swabs and urine samples can be used as proxies for each other. Because SUC often misses microbes, we used two more sensitive, recently validated detection methods to compare the composition of the urinary and vaginal microbiomes of pregnant females in their first trimester. Both methods yielded similar results. Vaginal and urinary microbial compositions for the same individual were significantly correlated; however, they were not equivalent. We argue that first trimester urinary and vaginal microbiomes are distinct enough to preclude their use as proxies for each other.

BACTERIAL PROFILE, ANTIMICROBIAL RESISTANCE, AND FACTORS ASSOCIATED WITH URINARY TRACT INFECTION AMONG PREGNANT WOMEN AT HOSANNA TOWN HEALTH FACILITIES, CENTRAL ETHIOPIA.

Urinary tract infection in pregnancy is a common microbial infection. Antimicrobial resistance among uropathogens is becoming a major health problem worldwide. The antimicrobial agents used to manage urinary tract infections during pregnancy should be carefully chosen. Therefore, this study aimed to determine the bacterial profile, antibiotic susceptibility pattern, and factors associated with urinary tract infection among pregnant women at Hosanna town public health facilities. A facility-based cross-sectional study was conducted from March to August 2022 on a total of 312 pregnant women who attended antenatal care at Hosanna Town public health facilities. Sociodemographic, clinical data, and related information were collected by using a pre-tested questionnaire. In addition, mid-stream urine specimens were collected from study participants. Bacterial pathogens were identified by standard bacteriological techniques. Antibiotic susceptibility testing was performed by using the Kirby Bauer disk diffusion method. The data were analyzed by using SPSS version 25. Chi-square and odds ratios were calculated and a P-value≤0.05 at a 95% confidence interval was considered statistically significant. The results were presented with words and tables. Of a total of pregnant women, 59/312(18.9%) (95% CI: 14.7-23.7) were found to have significant bacteriuria. The predominant isolates were Escherichia coli (E. coli) 22(34.4%), followed by coagulase-negative staphylococci (CoNS) 10(15.6%), Staphylococci aureus (S. aureus) 7(10.9%), and Klebsiella pneumoniae (K. pneumoniae) 6(9.4%). Overall, 78.1% of these isolates were multidrug-resistant (MDR). Gram-negative bacteria were susceptible to meropenem (97.6%), gentamicin (85.7%), nitrofurantoin (82.1%), ciprofloxacin (73.8%), amoxicillin-clavulanic acid (73.8%) and ceftriaxone (71.8%), but highly resistant to ampicillin (95.5%), trimethoprim-sulfamethoxazole (74.4%), doxycycline (71.8%), cefuroxime (69.2%), and cephalexin (69.2%). The gram-positive bacteria were susceptible to gentamicin (86.4%), erythromycin (81.8%), and nitrofurantoin (77.3%): whereas they showed a high level of resistance to penicillin (72.7%), doxycycline (54.5%), trimethoprim-sulfamethoxazole (52.9%), and cefoxitin (52.9%). No formal education for the participant (AOR: 2.86, 95% CI: 1.03-7.98, p=0.044), family monthly income <1500 birr (AOR: 3.19, 95% CI: 1.48-6.89, p=0.003), and previous history of UTI (AOR: 4.52, 95% CI: 2.04-10.03, p=0.001) were significantly associated with bacteriuria. This study revealed a high prevalence of bacterial urinary tract infection among pregnant women and low susceptibility to ampicillin, trimethoprim-sulfamethoxazole, cefuroxime, and cephalexin. Therefore, regularly, culture-based bacterial identification and antibiotic susceptibility testing should be performed. Alternatively, empiric antibiotic therapy should consider the prevalence of antibiotic-resistant uropathogens and the factor that may increase the urinary tract infection occurrence due to multi-drug resistant uropathogens.

Antibiogram of uropathogens and associated risk factors among asymptomatic female college students in Dessie town, Northeast Ethiopia.

BACKGROUND: Asymptomatic urinary tract infection (asymptomatic bacteriuria and asymptomatic candiduria) may not be routinely detected in sexually active non-pregnant female population at the initial and reversible stages. This is mainly due to the fact that most women may not feel compelled to seek medical attention. OBJECTIVES: The aim of this study was to determine the prevalence, and factors associated with urinary tract infection (UTI), and antibiogram of the uropathogen isolates among asymptomatic female college students. METHODS: An institutional-based cross-sectional study was conducted at selected colleges in Dessie from January 2021-March 2021. A total of 422 reproductive age (15 to 49 years) non-pregnant female students were included. Socio-demographic and clinical characteristics data were collected using structured questionnaires. Ten mLs of freshly voided mid-stream urine specimen was collected, transported and processed according to the standard operating procedures. Data were coded and entered for statistical analysis using SPSS version 22.0. Descriptive statistics, bivariate and multivariate logistic regression analysis were performed and p-values <0.05 with the corresponding 95% confidence interval (CI) were considered statistically significant. RESULT: The overall prevalence of UTI was 24.6%. The prevalence of asymptomatic UTI bacteriuria and candiduria was 57 (13.5%) and 47 (11.1%), respectively. The predominant uropathogens were Staphylococcus saprophyticus 24 (23.1%), followed by Candida tropicalis 23 (22.1%), Candida albican 10 (9.6%), Candida krusei 9 (8.7%) and Escherichia coli 8 (7.7%). Gram negative bacterial isolates showed a higher level of resistance to amoxicillin-clavulanic acid 24 (92.3%). Gram positive bacterial uropathogens showed high level of resistance to penicillin 28 (96.6%) and trimethoprim-sulfamethoxazole 23 (79.3%). Gram positive bacterial isolates were sensitive to norfloxacin, clindamycin, and ciprofloxacin, accounting for 24 (82.7%), 20 (69.0%), and 19 (65.5%), respectively. Multidrug resistance was seen in 50 (87.7%) of bacterial uropathogens. Factors identified for acquisition of UTI were frequency of sexual intercourse (≥3 per week) (AOR = 7.91, 95% CI: (2.92, 21.42), and genital area washing habit (during defecation (AOR = 5.91, 95%CI: (1.86, 18.81) and every morning (AOR = 6.13, 95%CI: (1.60, 23.45)). CONCLUSION: A significant prevalence of uropathogens, and high resistance of bacterial isolates to the commonly prescribed drugs were detected. Therefore, routine UTI screening, regular health education on the risk of asymptomatic infectious diseases for reproductive age group females, and antimicrobial susceptibility testing should be practiced to avoid the progression of an asymptomatic infection into a symptomatic UTI.

Bacterial profile and prevalence of urinary tract infections in pregnant women in Latin America: a systematic review and meta-analysis.

BACKGROUND: Given the physiological changes during pregnancy, pregnant women are likely to develop recurrent urinary tract infections (UTIs) and pyelonephritis, which may result in adverse obstetric outcomes, including prematurity and low birth weight preeclampsia. However, data on UTI prevalence and bacterial profile in Latin American pregnant women remain scarce, necessitating the present systematic review to address this issue. METHODS: To identify eligible observational studies published up to September 2022, keywords were systematically searched in Medline/PubMed, Cochrane Library, Embase, Web of Science, and Bireme/Lilacs electronic databases and Google Scholar. The systematic review with meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and the quality of studies was classified according to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines. The meta-analysis employed a random-effects method with double-arcsine transformation in the R software. RESULTS: Database and manual searches identified 253,550 citations published until September 2022. Among the identified citations, 67 met the inclusion criteria and were included in the systematic review, corresponding to a sample of 111,249 pregnant women from nine Latin American countries. Among Latin American pregnant women, the prevalence rates of asymptomatic bacteriuria, lower UTI, and pyelonephritis were estimated at 18.45% (95% confidence interval [CI]: 15.45-21.53), 7.54% (95% CI: 4.76-10.87), and 2.34% (95% CI: 0.68-4.85), respectively. Some regional differences were also detected. Among the included studies, Escherichia coli (70%) was identified as the most frequently isolated bacterial species, followed by Klebsiella sp. (6.8%). CONCLUSION: Pregnant women in Latin America exhibit a higher prevalence of bacteriuria, UTI, and pyelonephritis than pregnant women globally. This scenario reinforces the importance of universal screening with urine culture during early prenatal care to ensure improved outcomes. Future investigations should assess the microbial susceptibility profiles of uropathogens isolated from pregnant women in Latin America. TRIAL REGISTRATION: This research was registered at PROSPERO (No. CRD42020212601).

The diagnostic performances of the Atellica® 1500 automated urinalysis system for ruling out bacterial urinary tract infection.

Urinary tract infection (UTI) is one of the most common diseases occurring in both hospitalized and community subjects. Urine culture is the gold standard test for the diagnosis of UTI, but approximately 80% are negative. The aim of this study was to evaluate the performance of the automated urinalysis system Atellica® 1500 (Siemens Healthineers, Erlangen, Germany) as screening tool for ruling out UTI. A total of 5,490 urine specimens from outpatients, that had simultaneous requests for urinalysis and urine culture, were evaluated. Of the 5,490 samples, 833 (15.2 %) resulted positive for urine culture. Among UTI-related parameters, bacterial count was considered the most apt to be diagnostic of subjects affected by UTI. Using a cutoff value for bacteria count equal to 180 elements/µL, Atellica® 1500 detected bacteriuria with diagnostic sensitivity (Se) of 88.1 %, diagnostic specificity (Sp) of 82.1 %, and negative predictive value (NPV) of 95.2 %. Comparing our results with the literature's data, we observed that our Se and NPV were lower, while our Sp was higher. Our data showed that the Atellica® 1500 system detected bacteria with satisfactory analytical performance, but the results obtained do not make it a reliable tool for excluding UTI with urinalysis.

A double-blinded randomized placebo-controlled non-inferiority trial protocol for postoperative infections associated with canine pyometra.

BACKGROUND: Pyometra is a common infectious condition, especially in elderly bitches. In addition to an infected uterus, dogs may have concurrent urinary tract infection (UTI). The preferred treatment is surgical removal of the ovaries and uterus, whereupon the general prognosis is excellent. In addition, antimicrobial therapy is frequently prescribed for postoperative treatment. However, no research exists on the benefit of postoperative antimicrobial treatment in uncomplicated canine pyometra. Antimicrobial resistance has become a major challenge in treatment of bacterial infections. Diminishing overuse of antimicrobial agents is essential for controlling the development of antimicrobial resistance in both animals and humans. METHODS: This double-blinded, randomized, placebo-controlled two-arm clinical trial is designed to compare the incidence of postoperative infections associated with surgical treatment of uncomplicated pyometra followed by two different treatment protocols. For the study, 150 dogs presenting with an uncomplicated pyometra and that are to undergo surgical treatment will be recruited. Dogs with body weight < 3 or > 93 kg, complicated pyometra, primary disease increasing the risk of infection, or immunosuppressive medication will be excluded. All dogs will receive one dose of sulfadoxine-trimethoprim intravenously as an antimicrobial prophylaxis. Postoperatively, dogs will be randomized to receive either a five-day course of placebo or an active drug, sulfadiazine-trimethoprim orally. During the surgery microbiological samples will be taken from urine and uterine content. The follow-up includes a control visit in 12 days and an interview of the owner 30 days after surgery. If bacteriuria is detected at the time of surgery, a urinary sample will be cultured for bacterial growth at the control visit. The primary outcome is the incidence of a postoperative surgical site infection (SSI), and the secondary outcome is the occurrence of clinical UTI with bacteriuria. Intention-to-treat and per-protocol analyses will be performed to compare outcome incidences between the treatment groups. DISCUSSION: Research-based evidence is necessary to create treatment guidelines for judicious use of antimicrobials. The goals of this study are to provide evidence for reducing the use of antimicrobials and targeting the treatment to patients proven to benefit from it. Publishing the trial protocol will increase transparency and promote open science practices.

The Role of Mobile Genetic Elements in Virulence Factor Carriage from Symptomatic and Asymptomatic Cases of Escherichia coli Bacteriuria.

Uropathogenic Escherichia coli (UPEC) is extremely diverse genotypically and phenotypically. Individual strains can variably carry diverse virulence factors, making it challenging to define a molecular signature for this pathotype. For many bacterial pathogens, mobile genetic elements (MGEs) constitute a major mechanism of virulence factor acquisition. For urinary E. coli, the total distribution of MGEs and their role in the acquisition of virulence factors is not well defined, including in the context of symptomatic infection versus asymptomatic bacteriuria (ASB). In this work, we characterized 151 isolates of E. coli, derived from patients with either urinary tract infection (UTI) or ASB. For both sets of E. coli, we catalogued the presence of plasmids, prophage, and transposons. We analyzed MGE sequences for the presence of virulence factors and antimicrobial resistance genes. These MGEs were associated with only ~4% of total virulence associated genes, while plasmids contributed to ~15% of antimicrobial resistance genes under consideration. Our analyses suggests that, across strains of E. coli, MGEs are not a prominent driver of urinary tract pathogenesis and symptomatic infection. IMPORTANCE Escherichia coli is the most common etiological agent of urinary tract infections (UTIs), with UTI-associated strains designated "uropathogenic" E. coli or UPEC. Across urinary strains of E. coli, the global landscape of MGEs and its relationship to virulence factor carriage and clinical symptomatology require greater clarity. Here, we demonstrate that many of the putative virulence factors of UPEC are not associated with acquisition due to MGEs. The current work enhances our understanding of the strain-to-strain variability and pathogenic potential of urine-associated E. coli and points toward more subtle genomic differences distinguishing ASB from UTI isolates.

Genome profiling of uropathogenic E. coli from strictly defined community-acquired UTI in paediatric patients: a multicentric study.

BACKGROUND: Urinary tract infection (UTI) in children is a common bacterial infection. The emergence of extended-spectrum beta-lactamases (ESBLs) poses a major challenge against the treatment of uropathogens. We aimed to characterize the E. coli isolates recovered from children with UTI for their resistance profile and circulating sequence types (ST). METHODS: Children (> 1.5-18 years of age) from different community health centres of India with symptoms of UTI were enrolled. Isolates causing significant bacteriuria were identified by Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) and tested for antimicrobial susceptibility by the automated system, VITEK-2 (Biomeriux, Durhum, US). Nineteen E. coli isolates (15 ESBL positive and 4 ESBL negative) were sequenced in Oxford Nanopore platform followed by core-genome phylogeny, accessory genome cluster analysis, identification of sequence types, mobile genetic elements, genetic antimicrobial resistance markers. The correlation between detection of antimicrobial resistance genes with phenotypic resistance profiles was also investigated. RESULTS: Eleven percent of children had significant bacteriuria [male:female-1:1, > 50% were 11-18 years of age group]. E. coli was predominant (86%) followed by K. pneumoniae (11%). Susceptibility of E. coli was highest against fosfomycin (100%) followed by carbapenems (90.7%) and nitrofurantoin (88.8%). ST131 (15.8%) and ST167 (10.5%) found as high-risk clones with the presence of plasmid [IncFIB (63.1%), IncFIA (52.6%)], and composite transposon [Tn2680 (46.6%)] in many isolates. Few isolates coharboured multiple beta-lactamases including blaNDM-5 (33.3%), blaOXA-1 (53.3%), blaCTX-M-15 (60%) and blaTEM-4 (60%). CONCLUSIONS: This study highlights horizontal transmission of resistance genes and plasmids in paediatric patients at community centers across the nation harbouring multidrug-resistant genes such as blaNDM-5 and blaCTX-M-15 associated with high-risk clones ST131 and ST167. The data is alarming and emphasizes the need for rapid identification of resistance markers to reduce the spread in community. To our knowledge, this is the first multicentric study targeting paediatric UTI patients from the community setting of India.

Evaluation of a rapid immunoassay for bacteriuria in dogs.

BACKGROUND: The ability to detect bacteriuria in dogs with a point-of-care test might improve medical care and antimicrobial stewardship. HYPOTHESIS AND OBJECTIVE: A rapid immunoassay (RIA; RapidBac) will provide acceptable sensitivity and specificity for diagnosis of bacteriuria. ANIMALS: Forty-four client-owned dogs with a clinical indication for urinalysis and aerobic bacterial urine culture. METHODS: Prospective study. Urine, collected by cystocentesis, was submitted for urinalysis and culture at a diagnostic laboratory. Owners completed an enrollment questionnaire regarding their dogs' clinical signs. The RIA was performed according to the manufacturer's guidelines. Results were compared to culture. RESULTS: Forty-four urine specimens were evaluated from 44 dogs. The sensitivity and specificity of the RIA test to detect bacteriuria compared to urine culture were 81.8% (95% CI, 65.7%-97.9%) and 95.5% (95% CI, 86.8%-99.9%), respectively. For cultures yielding ≥103  CFU/mL, sensitivity increased to 90.0% (95% CI, 76.9%-100%) and specificity was similar at 95.2% (95% CI, 86.1%-99.9%). Malodorous urine, bacteriuria, and pyuria were more likely to be present in dogs with positive RIA or urine culture results compared to dogs with negative results. CONCLUSIONS AND CLINICAL IMPORTANCE: The RIA was easy to perform and had good sensitivity and excellent specificity in this group of dogs. The RIA might be a useful screening test for decision-making regarding antimicrobial therapy in dogs with a clinical indication for urine culture. Consideration could be given to amending the International Society for Companion Animal Infectious Disease definition of bacterial cystitis as the presence of signs of lower urinary tract disease together with positive culture or a positive RIA.

Clinical significance of concomitant bacteriuria in patients with Staphylococcus aureus bacteraemia.

This retrospective study, conducted at Lausanne University Hospital (2015-2021), compared Staphylococcus aureus bacteraemia (SABA) patients with or without concomitant bacteriuria (SABU). Among 448 included bacteraemic patients, 62 (13.8%) had S. aureus concurrently isolated from urine. In multivariate analysis, there was a significant difference in the odds of community-onset bacteraemia (P 0.030), malignancy (P 0.002), > 1 pair of positive blood cultures (P 0.037), and persistent bacteraemia for at least 48 h (P 0.045) in patients with concurrent SABU. No difference concerning mortality was found. On the other hand, SABU was associated with higher rates of SABA recurrence after antibiotic cessation.

E. coli catheter-associated urinary tract infections are associated with distinctive virulence and biofilm gene determinants.

Urinary catheterization facilitates urinary tract colonization by E. coli and increases infection risk. Here, we aimed to identify strain-specific characteristics associated with the transition from colonization to infection in catheterized patients. In a single-site study population, we compared E. coli isolates from patients with catheter-associated asymptomatic bacteriuria (CAASB) to those with catheter-associated urinary tract infection (CAUTI). CAUTI isolates were dominated by a phylotype B2 subclade containing the multidrug-resistant ST131 lineage relative to CAASB isolates, which were phylogenetically more diverse. A distinctive combination of virulence-associated genes was present in the CAUTI-associated B2 subclade. Catheter-associated biofilm formation was widespread among isolates and did not distinguish CAUTI from CAASB strains. Preincubation with CAASB strains could inhibit catheter colonization by multiple ST131 CAUTI isolates. Comparative genomic analysis identified a group of variable genes associated with high catheter biofilm formation present in both CAUTI and CAASB strains. Among these, ferric citrate transport (Fec) system genes were experimentally associated with enhanced catheter biofilm formation using reporter and fecA deletion strains. These results are consistent with a variable role for catheter biofilm formation in promoting CAUTI by ST131-like strains or resisting CAUTI by lower-risk strains that engage in niche exclusion.