Catheter-associated urinary tract infection by Pseudomonas aeruginosa progresses through acute and chronic phases of infection.

Healthcare-associated infections are major causes of complications that lead to extended hospital stays and significant medical costs. The use of medical devices, including catheters, increases the risk of bacterial colonization and infection through the presence of a foreign surface. Two outcomes are observed for catheterized patients: catheter-associated asymptomatic bacteriuria and catheter-associated urinary tract infection (CAUTI). However, the relationship between these two events remains unclear. To understand this relationship, we studied a murine model of Pseudomonas aeruginosa CAUTI. In this model, we also observe two outcomes in infected animals: acute symptoms that is associated with CAUTI and chronic colonization that is associated with asymptomatic bacteriuria. The timing of the acute outcome takes place in the first week of infection, whereas chronic colonization occurs in the second week of infection. We further showed that mutants lacking genes encoding type III secretion system (T3SS), T3SS effector proteins, T3SS injection pore, or T3SS transcriptional activation all fail to cause acute symptoms of CAUTI. Nonetheless, all mutants defective for T3SS colonized the catheter and bladders at levels similar to the parental strain. In contrast, through induction of the T3SS master regulator ExsA, all infected animals showed acute phenotypes with bacteremia. Our results demonstrated that the acute symptoms, which are analogous to CAUTI, and chronic colonization, which is analogous to asymptomatic bacteriuria, are independent events that require distinct bacterial virulence factors. Experimental delineation of asymptomatic bacteriuria and CAUTI informs different strategies for the treatment and intervention of device-associated infections.

Bladder catheterization improves bacterial interference with asymptomatic Escherichia coli 83972 in an experimental porcine model of urinary tract infection.

BACKGROUND: Urinary tract infection (UTI) is a common disease with a significant risk of relapse. Deliberate bladder colonization with asymptomatic Escherichia coli is being explored as a potential strategy to fend off invading uropathogens thereby mitigating the risk symptomatic UTI. Currently, one major obstacle is the low success rates for achieving persistent bladder colonization with asymptomatic bacteria and experimental challenge studies are lacking. Here, we assessed the influence of an indwelling bladder catheter on the ability of asymptomatic E. coli to colonize the bladder and to assess the protective efficacy of such colonization against experimental urinary tract infection with uropathogenic E. coli. METHODS: Pigs with or without indwelling bladder catheters were experimentally inoculated with the asymptomatic E. coli strain 83972 and subsequently challenged by inoculation with the uropathogenic E. coli isolate, UTI89. The animals were monitored with regular urine and blood samples and bladders and kidneys were harvested at termination. RESULTS: All pigs with indwelling catheters were colonized by 83972 in response to inoculation, compared to pigs without catheters in which only one of eight animals were colonized. When removing the catheter, 83972 were spontaneously cleared. Colonization with 83972 prevented experimental infection in 50% of animals compared to controls that all became infected. CONCLUSIONS: The presence of indwelling bladder catheters strongly facilitates the colonization of 83972, indicating that individuals using catheters may be particularly suited for receiving this treatment. The research supports prophylactic colonization with 83972 as a potential strategy to reduce the risk of urinary tract infections.

Development of Patient Safety Measures to Identify Inappropriate Diagnosis of Common Infections.

BACKGROUND: Inappropriate diagnosis of infections results in antibiotic overuse and may delay diagnosis of underlying conditions. Here we describe the development and characteristics of 2 safety measures of inappropriate diagnosis of urinary tract infection (UTI) and community-acquired pneumonia (CAP), the most common inpatient infections on general medicine services. METHODS: Measures were developed from guidelines and literature and adapted based on data from patients hospitalized with UTI and CAP in 49 Michigan hospitals and feedback from end-users, a technical expert panel (TEP), and a patient focus group. Each measure was assessed for reliability, validity, feasibility, and usability. RESULTS: Two measures, now endorsed by the National Quality Forum (NQF), were developed. Measure reliability (derived from 24 483 patients) was excellent (0.90 for UTI; 0.91 for CAP). Both measures had strong validity demonstrated through (a) face validity by hospital users, the TEPs, and patient focus group, (b) implicit case review (ĸ 0.72 for UTI; ĸ 0.72 for CAP), and (c) rare case misclassification (4% for UTI; 0% for CAP) due to data errors (<2% for UTI; 6.3% for CAP). Measure implementation through hospital peer comparison in Michigan hospitals (2017 to 2020) demonstrated significant decreases in inappropriate diagnosis of UTI and CAP (37% and 32%, respectively, P < .001), supporting usability. CONCLUSIONS: We developed highly reliable, valid, and usable measures of inappropriate diagnosis of UTI and CAP for hospitalized patients. Hospitals seeking to improve diagnostic safety, antibiotic use, and patient care should consider using these measures to reduce inappropriate diagnosis of CAP and UTI.

Asymptomatic bacteriuria screening for developing countries using a modified water quality test kit.

Between 2% and 15% of pregnant women unknowingly experience asymptomatic bacteriuria (ASB), defined as ≥105 CFU per milliliter of urine in the absence of symptoms. ASB increases the risk of adverse pregnancy outcomes including pyelonephritis, preterm labor, and low-birth weight infants. While pregnant women in the United States are routinely screened for ASB, those in developing countries with limited resources and funding lack an accurate mechanism for ASB screening. Aquagenx water quality test kits detect Escherichia coli, the most common causative agent of ASB, and total coliform bacteria in drinking water via colorimetric and fluorescent indicators. We found that the Aquagenx system is compatible with human urine and then proceeded to develop an ASB screening protocol using disposable inoculating loops. Our protocol diagnosed artificial ASB- samples (104 CFU/mL E. coli) with a false positive (FP) rate of 33% (n = 18) and ASB+ (105 CFU/mL E. coli) with a false negative (FN) rate of 5.6% (n = 18). Clinical sample testing with our protocol revealed a FP rate of 0% in ASB- samples (n = 28) and a FN rate of 0% in ASB+ samples caused by coliforms (n = 13). Aquagenx did not detect ASB in nine clinical samples with non-coliform etiological agents due to the limitations of the technology. However, with very high accuracy for detection of E. coli and other causative agents that collectively account for 90.1% of ASB cases, these kits could be used as a diagnostic ASB screening tool in developing countries in which there is currently no alternative to urine culture.IMPORTANCEAsymptomatic bacteriuria (ASB) affects 2%-15% of pregnant women and can result in adverse maternal and fetal outcomes if left undetected and untreated. In the United States and other developed nations, pregnant women are regularly screened for ASB via urine culture. However, in low-resource countries where bacterial culture is not available, dipstick testing is used. Although accurate in cases of symptomatic bacteriuria, dipstick detection is ineffective for detecting ASB. Here, we made use of an existing water quality field test for ASB urine screening, which would be readily deployable in low-resource settings. We optimized a dilution protocol for sampling patient urine within the detection limits of the Aquagenx kit technology. Overall, we were able to detect ASB samples with Gram-negative pathogens that collectively account for 90% of all ASB cases. Utilization of this repurposed technology for proactive medical screening may help prevent adverse pregnancy and birth outcomes due to ASB.

Proposing the "Continuum of UTI" for a Nuanced Approach to Diagnosis and Management of Urinary Tract Infections.

PURPOSE: Patients with suspected UTIs are categorized into 3 clinical phenotypes based on current guidelines: no UTI, asymptomatic bacteriuria (ASB), or UTI. However, all patients may not fit neatly into these groups. Our objective was to characterize clinical presentations of patients who receive urine tests using the "continuum of UTI" approach. MATERIALS AND METHODS: This was a retrospective cohort study of a random sample of adult noncatheterized inpatient and emergency department encounters with paired urinalysis and urine cultures from 5 hospitals in 3 states between January 01, 2017, and December 31, 2019. Trained abstractors collected clinical (eg, symptom) and demographic data. A focus group discussion with multidisciplinary experts was conducted to define the continuum of UTI, a 5-level classification scheme that includes 2 new categories: lower urinary tract symptoms/other urologic symptoms and bacteriuria of unclear significance. The newly defined continuum of UTI categories were compared to the current UTI classification scheme. RESULTS: Of 220,531 encounters, 3392 randomly selected encounters were reviewed. Based on the current classification scheme, 32.1% (n = 704) had ASB and 53% (n = 1614) did not have a UTI. When applying the continuum of UTI categories, 68% of patients (n = 478) with ASB were reclassified as bacteriuria of unclear significance and 29% of patients (n = 467) with "no UTI" were reclassified to lower urinary tract symptoms/other urologic symptoms. CONCLUSIONS: Our data suggest the need to reframe our conceptual model of UTI vs ASB to reflect the full spectrum of clinical presentations, acknowledge the diagnostic uncertainty faced by frontline clinicians, and promote a nuanced approach to diagnosis and management of UTIs.

Asymptomatic Bacteriuria and Urological Surgery: Risk Factor or Not? Results From the National and Multicenter TOCUS Database.

PURPOSE: Current guidelines recommend screening and treatment of asymptomatic bacteriuria prior to all urological surgeries breaching the mucosa. But little evidence supports this recommendation. At the least, risk stratification for postoperative UTI to support this strategy is lacking. The aim of this study was to define the associated factors for postoperative febrile infectious complications (UTI or surgical site infection) in urological surgery. MATERIALS AND METHODS: We conducted a retrospective, multicentric study including all consecutive patients undergoing any urological surgery with preoperative urine culture. The primary outcome was the occurrence of a UTI or surgical site infection occurring within 30 days after surgery. RESULTS: From 2016 to 2023, in 10 centers, 2389 patients were included with 838 (35%) positive urine cultures (mono-/bi-/polymicrobial). Postoperative infections occurred in 106 cases (4.4%), of which 44 had negative urine cultures (41%), 42 had positive mono-/bimicrobial urine cultures (40%), and 20 had polymicrobial urine cultures (19%). In multivariable analysis, UTI during the previous 12 months of surgery (odds ratio [OR] 3.43; 95% CI 2.07-5.66; P < .001), monomicrobial/bimicrobial preoperative urine culture (OR 3.68; 95% CI 1.57-8.42; P = .002), polymicrobial preoperative urine culture (OR 2.85; 95% CI 1.52-5.14; P < .001), and operative time (OR 1.09; 95% CI 1.04-1.15; P < .001) were independent associated factors for postoperative febrile infections. CONCLUSIONS: Positive urine culture, including preoperative polymicrobial urine culture, prior to urological surgery was associated with postoperative infection. Additionally, patients experiencing infectious complications also had a higher incidence of other complications. The effectiveness of systematic preventive antibiotic therapy for a positive urine culture has not been conclusively established.

Urinary Tract Infections: Core Curriculum 2024.

Urinary tract infections (UTIs) are some of the most commonly encountered infections in clinical practice. Accurate diagnosis and evidence-based treatment of UTIs will lead to better clinical care for many patients and limit unnecessary antibiotic use. Urinalysis and urine cultures are helpful tools in the diagnosis of UTIs; however, it is important to recognize their limitations. Differentiating between asymptomatic bacteriuria (ASB) and true UTI is important because antibiotics are unnecessary in most nonpregnant patients with ASB and can even potentially cause harm if prescribed. Choice and duration of antibiotics varies across the spectrum of UTI syndromes such as acute uncomplicated cystitis, pyelonephritis, prostatitis, and catheter-associated UTIs. The treatment approach also depends on patients' degree of immunosuppression and their genitourinary anatomy. Therefore, patients with urological obstruction or kidney transplants may require a specialized and multidisciplinary management approach. For individuals prone to frequent UTIs, some preventative measures can be utilized, yet there is often not a "one size fits all" approach.

Diabetes, SGLT-2 Inhibitors, and Urinary Tract Infection: a Review.

PURPOSE OF REVIEW: The aim of this review is to focus on epidemiology, pathogenesis, risk factors, management, and complications of UTI in people with diabetes as well as reviewing the association of SGLT-2 inhibitors with genitourinary infections. RECENT FINDINGS: Individuals diagnosed with T2DM are more prone to experiencing UTIs and recurrent UTIs compared to individuals without T2DM. T2DM is associated with an increased risk of any genitourinary infections (GUI), urinary tract infections (UTIs), and genital infections (GIs) across all age categories. SGLT2 inhibitors are a relatively new class of anti-hyperglycemic agents, and studies suggest that they are associated with an increased risk of genitourinary infections. The management of diabetes and lifestyle modifications with a patient-centric approach are the most recognized methods for preventing critical long-term complications including genitourinary manifestations of diabetes. The available data regarding the association of SGLT-2 inhibitors with genitourinary infections is more comprehensive compared to that with UTIs. Further research is needed to better understand the mechanisms underlining the association between SGLT-2 inhibitors and genital infections and UTIs.

Genotypic and phenotypic characterisation of asymptomatic bacteriuria (ABU) isolates displaying bacterial interference against multi-drug resistant uropathogenic E. Coli.

Escherichia coli can colonise the urogenital tract of individuals without causing symptoms of infection, in a condition referred to as asymptomatic bacteriuria (ABU). ABU isolates can protect the host against symptomatic urinary tract infections (UTIs) by bacterial interference against uropathogenic E. coli (UPEC). The aim of this study was to investigate the genotypic and phenotypic characteristics of five ABU isolates from midstream urine samples of adults. Comparative genomic and phenotypic analysis was conducted including an antibiotic resistance profile, pangenome analysis, and a putative virulence profile. Based on the genome analysis, the isolates consisted of one from phylogroup A, three from phylogroup B2, and one from phylogroup D. Two of the isolates, PUTS 58 and SK-106-1, were noted for their lack of antibiotic resistance and virulence genes compared to the prototypic ABU strain E. coli 83,972. This study provides insights into the genotypic and phenotypic profiles of uncharacterised ABU isolates, and how relevant fitness and virulence traits can impact their potential suitability for therapeutic bacterial interference.

An in-vitro model for bacteria-related catheter encrustations.

PURPOSE: About 50% of individuals with long-term indwelling catheters are affected by catheter encrustations and bladder stone formation. Therefore, prophylaxis of catheter encrustations is important. Currently, however, neither an established prophylaxis nor a standardized in-vitro model to test different measures exist. We have therefore developed and qualitatively evaluated an in-vitro model of catheter encrustation. METHODS: Size 14 French suprapubic catheters were incubated under sterile conditions at 37 degrees Celsius in five different media: (1) sterile artificial urine (n = 16), (2) artificial urine with E. coli (n = 8), (3) with Pseudomonas aeruginosa (n = 8), (4) with Proteus mirabilis (n = 8), and (5) with a mix of these three strains (n = 8). Catheter balloons were inflated either a glycerine or a bactericidal solution. After 6 weeks, the catheters were removed from the solution, dried, and weighed, and a photometric determination of the retrieved encrustations was performed. RESULTS: Most frequently and pronounced encrustations were detected in the Pseudomonas group. The median weight of these encrustations (50% struvite and brushite) was 84.4 mg (47.7 mg / 127.3 mg). Even on catheters stored in sterile urine, encrustations (69.2% struvite) were found. Bacterial growth was not affected by the medium used for catheter blockage. CONCLUSION: Although in-vitro models appear to be limited because they lack "the human factor", they are valuable for systematically assessing physico-chemical factors affecting encrustations. Therefore, our model, being reliable and cost-effective, may foster further research despite its limitations.

Bacteriuria in patients with stented ureters: predictors of infection in patients presenting to the hospital and when not to treat.

PURPOSE: Patients with ureteric stents have symptoms that overlap with infection symptoms. Thus, clinicians unnecessarily give antibiotics to stented patients with bacteriuria despite guidelines. In stented patients, little is known about risk factors for developing bacteriuria or urosepsis. The objectives were to identify the frequency and risk factors for developing bacteriuria and urosepsis in patients with stents. METHODS: In this retrospective cohort study, we reviewed patients with ureteric stents placed or exchanged over 1 year. We examined associations between bacteriuria or urosepsis and host risk factors. Univariable and multivariable logistic analyses were performed. RESULTS: Of 286 patients (mean age: 57.2 years), 167 (58.4%) were male. The main stent indications were stone, stricture, cancer and extrinsic compression. The median stented period was 61 days. The frequency of bacteriuria was 59/286 (21%). ASA status 3 and 4 had 5 times the odds of having bacteriuria relative to ASA status 1. Stent duration > 2 months had 5.5 times the odds relative to ≤ 2 months. Urosepsis was infrequent, 13/286 (4.5%). Five patients had bacteraemia. A stent duration over 2 months had nearly 6 times the odds of urosepsis. CONCLUSION: ASA status higher than 2 and stent time greater than 2 months raise the odds of developing bacteriuria. A stent duration longer than 2 months was the only predictor of urosepsis. Though 21% of patients had bacteriuria, 4.5% had urosepsis. Hence, bacteriuria without sepsis should not be treated with antibiotics, thus aiding antimicrobial stewardship.

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.

Risk factors and outcomes of bloodstream infection from a urinary source in kidney transplant recipients.

BACKGROUND: Bacteriuria is common among kidney transplant recipients (KTR). Risk factors and outcomes associated with bloodstream infection due to a urinary source (BSIU) in KTR are poorly understood. METHODS: This single center case-control study from 2010 to 2022 compared KTR with BSIU to those with bacteria without bloodstream infection (BU). Multivariable logistic regression identified BSIU risk factors, and Cox models assessed its impact on graft failure. RESULTS: Among 3435 patients, who underwent kidney transplantation at Emory Hospital, 757 (22%) developed bacteriuria, among whom 142 (18.8%) were BSIU. Male sex, presence of Escherichia coli, Klebsiella pneumoniae, or Pseudomonas species in urine culture, urethral stricture, neuromuscular bladder disorder, and history of diabetes-induced renal failure were independently associated with increased odds of BSIU (Male sex: aOR 2.29, 95% CI 1.52, 3.47, E. coli: aOR 5.14, 95% CI 3.02, 9.13; K. pneumoniae aOR 3.19, 95% CI 1.65, 6.27, Pseudomonas spp aOR 3.06, 95% CI 1.25, 7.18; urethral stricture: 4.10, 95% CI 1.63, 10.3, neuromuscular bladder disorder aOR 1.98, 95% CI 1.09, 3.53, diabetes: aOR 1.64, 95% CI 1.08, 2.49). BSIU was associated with increased hazard of graft failure (HR 1.52, 95% CI 1.05, 2.20). CONCLUSION: Close monitoring is warranted for male KTR with bacteriuria, those with urine cultures positive for Pseudomonas spp, K. pneumoniae, or E. coli, as well as KTR with a history of diabetes-induced renal failure, urethral stricture, or neuromuscular bladder disorder due to their risk for developing BSIU. Future research should explore strategies to mitigate BSIU risk in these high-risk KTR and reduce the associated risk of long-term graft failure.

Risk of infective endocarditis and complicated infection in Staphylococcus aureus bacteremia - a retrospective cohort study on the role of bacteriuria.

PURPOSE: S. aureus bacteremia (SAB) is a common and severe infection with high mortality and morbidity. The clinical relevance of the finding of concurrent S. aureus bacteriuria (SABU) is debated. The goal of this study was to analyze whether a concurrent SABU is associated with complicated SAB, infective endocarditis (IE) and mortality. METHODS: We conducted a retrospective cohort study, reviewing medical charts of all episodes of SAB in patients > 18 years in the region of Skåne, Sweden, between 1st of January and 31st of June 2020. Episodes where a concurrent urine culture was performed were included for analysis. An episode was considered as complicated SAB if there was either attributable mortality, recurrent infection, embolic stroke, or occurrence of a complicated focus of infection. RESULTS: During the study period, there were 279 episodes of SAB. 154 episodes met the eligibility criteria, of whom 37 (24%) had concurrent SABU. In 78 episodes (51%), the patients had a complicated SAB. There was a significantly lower proportion of complicated SAB for episodes with concurrent SABU (32%), compared to episodes without concurrent SABU (56%), p-value 0.014. Moreover, in the cohort there were 11 episodes (7.1%) of IE and a 30 days mortality rate of 16%, with no difference between the groups with or without SABU. CONCLUSIONS: There is an association between concurrent SABU and a decreased risk for complicated SAB among patients with SAB. This study found no significant association between SABU and neither IE nor mortality for patients with SAB.

Molecular detection of Staphylococcus aureus in urine in patients with S. aureus bacteremia: an exploratory study.

PURPOSE: Staphylococcus aureus bacteremia (SAB) is associated with a 90-day mortality of 28-34%. Many SAB-patients (7.8-39%) have a secondary S. aureus bacteriuria (SABU) mainly without symptoms of a urinary tract infection. Due to high morbidity and mortality, there is an interest in rapid detection of S. aureus bacteremia. Here, we compared a rapid nucleic acid amplification test (NAAT) with conventional culture to detect S. aureus in urine and to identify cases with increased risk for SAB. METHODS: In a cross-sectional study, we assessed urine samples (mid-stream, clean catch and catheter urine) of patients with SAB and bacteremia other than SAB (non-SAB). Urine samples were collected ± 3 days to the collection of the positive blood culture and were cultured on a set of selective and non-selective agar plates. NAAT was performed using a commercial test (Xpert® SA Nasal Complete G3, Cepheid) from a sterile swab soaked in urine. RESULTS: We included samples from 100 patients (68% male, median age: 67.4 years) with SAB and 20 patients (75% male, median age: 65.84 years) with non-SAB. The sensitivity of detecting SAB from urine samples was 47% (specificity: 90%) for NAAT, when applying a Ct-value of ≤ 37.4 for positive results. Urine culture had a sensitivity of 25% and a specificity of 95%. Molecular and culture methods showed a moderate agreement (80%, Cohens kappa: 0.55). CONCLUSION: NAAT from urine has a higher sensitivity than culture in patients with SAB and could potentially identify cases with increased risk for SAB. Future studies should investigate whether this characteristic could translate into a clinical benefit through rapid detection of SAB.

Bacteriuria and phenotypic antimicrobial susceptibility testing in 45 min by point-of-care Sysmex PA-100 System: first clinical evaluation.

PURPOSE: This study compared the results of the new Sysmex PA-100 AST System, a point-of-care analyser, with routine microbiology for the detection of urinary tract infections (UTI) and performance of antimicrobial susceptibility tests (AST) directly from urine. METHODS: Native urine samples from 278 female patients with suspected uncomplicated UTI were tested in the Sysmex PA-100 and with reference methods of routine microbiology: urine culture for bacteriuria and disc diffusion for AST. RESULTS: The analyser delivered bacteriuria results in 15 min and AST results within 45 min. Sensitivity and specificity for detection of microbiologically confirmed bacteriuria were 84.0% (89/106; 95% CI: 75.6-90.4%) and 99.4% (155/156; 95% CI: 96.5-100%), respectively, for bacterial species within the analyser specifications. These are Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Enterococcus faecalis and Staphylococcus saprophyticus, which are common species causing uncomplicated UTI. Overall categorical agreement (OCA) for AST results for the five antimicrobials tested in the Sysmex PA-100 (amoxicillin/clavulanic acid, ciprofloxacin, fosfomycin, nitrofurantoin and trimethoprim) ranged from 85.4% (70/82; 95%CI: 75.9-92.2%) for ciprofloxacin to 96.4% (81/84; 95% CI: 89.9-99.3%) for trimethoprim. The Sysmex PA-100 provided an optimal treatment recommendation in 218/278 cases (78.4%), against 162/278 (58.3%) of clinical decisions. CONCLUSION: This first clinical evaluation of the Sysmex PA-100 in a near-patient setting demonstrated that the analyser delivers phenotypic AST results within 45 min, which could enable rapid initiation of the correct targeted treatment with no further adjustment needed. The Sysmex PA-100 has the potential to significantly reduce ineffective or unnecessary antibiotic prescription in patients with UTI symptoms.

YELLOW RoUTIne prospective cohort study protocol: insight in the dynamics of bacteria in the elderly bladder.

BACKGROUND: Asymptomatic bacteriuria (ASB) - the presence of bacteria in urine without urinary tract infection (UTI) related signs & symptoms (S&S) - is common in the elderly bladder and is not considered pathogenic for UTI. We hypothesise that colonisation with non-uropathogenic bacteria could protect the bladder from invasion of more harmful bacteria. The exact role and dynamics of bacteriuria in the relation to the development of a UTI is still unknown. We aim to provide insight into the course of bacteriuria in the elderly bladder and its relation to UTI in frail older adults. METHODS AND ANALYSIS: A prospective observational cohort study is being conducted in Dutch nursing homes (NHs) between February 2024 and December 2025. Urine samples and case report forms (CRF) on UTI-related S&S will be collected from each consenting NH resident every 3 months for a follow-up period of 18 months. Whenever a UTI-suspicion occurs in between the 3 monthly time points, additional data and a urine sample will be collected. Urine samples undergo several urinalyses (e.g. dipstick and bacterial culture). Additional molecular analysis will be conducted on a selection of cultured Escherichia coli (E. coli) for virulence genes. Primary analyses will be conducted between residents with and without ASB at each time point. The primary outcome is UTI incidence during follow-up. In secondary analyses we will also take into account the low versus high presence of virulence genes of the E. coli. DISCUSSION: The combination of high ASB prevalence and a reduced ability of frail older adults to express UTI-related S&S may lead to UTI misdiagnosis and inappropriate antibiotic use. To our knowledge, this is the first study to investigate the dynamics and role of bacteriuria in the elderly bladder and their potential protective effect on the development of UTI. The study findings with comprehensive analysis of epidemiological, clinical and molecular data could set the fundamental base for future guidelines and studies, and contribute to improving prevention, diagnosis and treatment of UTI in frail older adults, in addition to contributing to antibiotic stewardship in NHs.

Open questions on lower urinary tract infections: Results of a Delphi consensus study.

BACKGROUND AND OBJECTIVE: This is a Delphi study that aims to explore expert consensus regarding open questions in current literature evidence on lower urinary tract infections (UTIs). This manuscript deals with adults and analyzed the most recent guidelines and meta-analysis on the topic. METHODS: A panel of leading urologists and urogynaecologists participated in a consensus-forming project using a Delphi method to reach consensus on gray zone issues on recurrent lower UTIns (rUTIs), asymptomatic bacteriuria (AB) in pregnant women, and catheter-associated UTIs (CAUTI) in adults. All the panelists were invited to participate the four phases consensus. Consensus was defined as ≥75% agreement. An ordinal scale (0-10) was used. A systematic literature review was analyzed for diagnostic workup and prevention of rUTIs, AB, and CAUTI. RESULTS: In total, 37 experts participated. All panelists participated in the four phases of the consensus process. Consensus was reached if ≥75% of the experts agreed on the proposed topic. Online meetings and a face-to-face consensus meeting was held in Milan in March 2023. Formal consensus was achieved for 12/13 items. CONCLUSIONS: This manuscript is a Delphi survey of experts that showed interest on some debated points on rUTIs, AB in pregnancy, and prevention of CAUTI. There is still little data on nonantibiotic prevention of UTIs and CAUTI; quite old studies have been reported on AB in pregnancy. The emerging problem of antibiotic resistance is relevant and nonantibiotic prophylaxis may play a role in its prevention.

Purulent pericarditis caused by methicillin-sensitive Staphylococcus aureus bacteriuria.

BACKGROUND: Purulent pericarditis (PP)- a purulent infection involving the pericardial space-requires a high index of suspicion for diagnosis as it often lacks characteristic signs of pericarditis and carries a mortality rate as high as 40% even with treatment. Common risk factors include immunosuppression, diabetes mellitus, thoracic surgery, malignancy, and uremia. Most reported cases of PP occur in individuals with predisposing risk factors, such as immunosuppression, and result from more commonly observed preceding infections, such as pneumonia, osteomyelitis, and meningitis. We report a case of PP due to asymptomatic bacteriuria in a previously immunocompetent individual on a short course of high-dose steroids. CASE PRESENTATION: An 81-year-old male presented for severe epigastric pain that worsened with inspiration. He had been on high-dose prednisone for presumed inflammatory hip pain. History was notable for urinary retention requiring intermittent self-catheterization and asymptomatic bacteriuria and urinary tract infections due to methicillin-sensitive Staphylococcus aureus (MSSA). During the index admission he was found to have a moderate pericardial effusion. Pericardial fluid cultures grew MSSA that had an identical antibiogram to that of the urine cultures. A diagnosis of purulent pericarditis was made. CONCLUSION: PP requires a high index of suspicion, especially in hosts with atypical risk factors. This is the second case of PP occurring as a result of asymptomatic MSSA bacteriuria. Through reporting this case we hope to highlight the importance of early recognition of PP and the clinical implications of asymptomatic MSSA bacteriuria in the setting of urinary instrumentation and steroid use.

Decision-making and Treatment Preferences Surrounding Bacteriuria in Nonpregnant Women: A Qualitative Investigation.

INTRODUCTION AND HYPOTHESIS: Best practices suggest nontreatment for asymptomatic bacteriuria in a nonpregnant population, yet there is little literature on patient preference or understanding of asymptomatic bacteriuria treatment. We hypothesize that there might be core factors that affect antibiotic preferences and care-seeking decisions for urinary tract infection and asymptomatic bacteriuria in a postmenopausal population. METHODS: We performed semi-structured interviews with postmenopausal individuals who had been previously treated for at least one patient-reported urinary tract infection. Interviews covered a discussion about their approach to seeking antibiotics for management and knowledge/preferences for asymptomatic bacteriuria management. Two authors independently coded the interviews and identified a set of symptom-related knowledge and experiences that relate to care-seeking and treatment preferences. We then graphically represented a mental model of antibiotic-seeking practices as an influence diagram, illustrating how knowledge and values affect preferences for care. RESULTS: We performed 30 interviews of participants with a mean age of 69.4 (SD 6.4). Among participants, there were four core factors that influence antibiotic seeking for bacteriuria. Participants noted concern for sequelae from untreated bacteria as their primary motivation, but also noted past experiences, information sources, and testing results as themes that affected their mental model surrounding bacteriuria treatment. CONCLUSIONS: The cognitive approach to care-seeking and treatment preference for bacteriuria is influenced by a few central factors. An improved ability to allay concerns either by provider discussions or educational materials are necessary to bridge the gap from the existence of evidence-based guidelines to patient and provider comfort with adherence to these guidelines.