Continuous low-dose antibiotic prophylaxis for adults with repeated urinary tract infections (AnTIC): a randomised, open-label trial

Extended Treatment-dose Antibiotic Therapy vs Low-dose Prophylaxis for the Management of Recurrent Uncomplicated Urinary Tract Infections in Peri- and Post-menopausal Women

OBJECTIVE

To assess treatment efficacy over 1year in women with recurrent urinary tract infection (UTI) receiving extended treatment-strength antibiotics compared to standard low-dose prophylactic antibiotic regimens.

METHODS

A retrospective cohort study of adult women presenting with acute uncomplicated UTI between January 1, 2018 and October 1, 2020 meeting recurrent UTI criteria (≥2 in 6months or ≥3 in 1year). Women were offered either: (1) treatment-strength antibiotic therapy for 1month; or (2) up to 7days of treatment-strength antibiotics followed by ≥3-month of low-dose prophylactic antibiotics. We excluded those with complicated UTI. The primary outcome was one or more symptomatic, culture-proven UTIs within 12months. Multivariable logistic regression assessed differences in the primary outcome while controlling for potential confounders.

RESULTS

Among the 246 patients, women receiving extended treatment dose antibiotics (n=43) had a significantly lower risk of experiencing subsequent UTI within 1year when compared to those receiving standard prophylactic dosing for ≥3-month (n=203) (rate 34.9% vs 59.6%; P<.01). This significant risk reduction was maintained in logistic regression analyses while controlling for potentially confounding variables (aOR 0.42; 95% CI 0.20, 0.89).

CONCLUSION

Women treated with a 1-month course of treatment-strength antibiotics had a significantly lower risk of subsequent UTI within 12months compared to women receiving ≥3-month of prophylactic antibiotics. These retrospective data preliminarily suggest that extended treatment-strength antibiotic dosing may provide therapeutic benefit while reducing overall cumulative antibiotic dose and duration. This innovative approach warrants further evaluation in randomized trials.

Insights into durability against resistance from the antibiotic nitrofurantoin

Nitrofurantoin has shown exceptional durability against resistance over 70 years of use. This longevity stems from factors such as rapid achievement of therapeutic concentrations, multiple physiological targets against bacteria, low risk of horizontal gene transfer, and the need to acquire multiple mutations to achieve resistance. These combined features limit resistance emergence and spread of nitrofurantoin resistance. We propose nitrofurantoin as an exemplar for developing other durable treatments.

Effectiveness and patient perspective on the use of intravesical gentamicin instillations to treat recurrent urinary tract infections in neurogenic lower urinary tract dysfunction

INTRODUCTION

Patients with neurogenic lower urinary tract dysfunction (NGLUTD) who require catheterization either with clean intermittent catheters (CIC) or indwelling catheters suffer with frequent urinary tract infections (UTIs). This study assessed the efficacy, patient persistence, satisfaction, and the impact on quality of life (QoL) of gentamicin nightly bladder instillations with 15 mg.

METHODS

This is a prospective survey of 36 patients with NGLUTD and recurrent UTIs prescribed long-term gentamicin to prevent UTIs. Eligible patients completed a questionnaire about their use and satisfaction with gentamicin therapy, as well as survey questionnaires to address QoL. A retrospective chart review was also performed to obtain medical history, confirm drug persistence, and obtain accurate UTI data for the 12 months preceding and after starting instillations.

RESULTS

The rate of laboratory proven symptomatic UTI requiring antibiotic treatment decreased from 3.9 to 1.1 infections per year with no increase in antibiotic resistance and no significant side effects reported by patients. Eight patients stopped therapy before a full year for various reasons, but the remaining 72% of patients have continued to use the therapy now with a mean of 4.2 years later. Satisfaction among those continuing the medication was very high.

CONCLUSION

Gentamicin bladder instillations with 15 mg nightly in patients with indwelling catheters or CIC with NGLUTD are very effective and safe with high patient satisfaction. This therapy can be maintained long-term with continued efficacy.

Trial to compare mixed-use (multi-use and single-use) intermittent catheter management with single-use management over 12 months (The MultICath Trial): protocol for a non-inferiority randomised controlled trial

INTRODUCTION

Evaluating the safety and acceptability of reusing catheters for intermittent catheterisation (IC) is one of the top 10 continence research priorities identified by the UK James Lind Alliance Priority Setting Partnership in 2008. There are an estimated 50 000 IC users in England and this number is rising. Globally, both single-use catheters (thrown away after use) and multi-use/reusable ones (cleaned between uses) are used. Using multi-use catheters as well as single-use ones (mixed-use) could bring benefits (eg, reducing plastic waste and patients never running out of catheters) and offer more choice to users. Evidence is needed that mixed-use is at least as safe and acceptable as using only single-use catheters.

METHODS

The MultICath Trial is a non-inferiority randomised controlled trial involving 578 participants. The aim is to compare mixed-use catheter management with single-use catheter management over 12 months. Participants are randomised on a 1:1 basis to either mixed-use catheter management, which includes an evidence-based cleaning method for the multi-use catheters (intervention) or single-use catheter management (control). Following randomisation, participants are followed up for 12 months. The primary outcome is at least one episode of microbiologically confirmed symptomatic urinary tract infection with help-seeking or self-help behaviour over the 12-month follow-up period. Laboratory analysis of patient-initiated urine samples is blind. Secondary outcomes include antibiotic use, microhaematuria, visible blood on catheter/in urine, quality of life and health economics. A qualitative sub-study to examine participant experiences using mixed-use is included.

ETHICS AND DISSEMINATION

Ethical review was undertaken by South Central-Hampshire A Research Ethics Committee and favourable opinion was granted on 12 July 2019 (reference: 19/SC/0334). Written, informed consent to participate was obtained from all participants. Results will be disseminated in peer-reviewed publications, in the National Institute for Health and Care Research journal library and to participants and the public via a lay summary published on the trial website.

TRIAL REGISTRATION NUMBER

ISRCTN42028483.

Check of APpropriaTeness of Antimicrobial therapy In Nursing homes (CAPTAIN):a point prevalence study in Belgium

Objectives

The overall prevalence of antimicrobial therapy (AMT) in nursing homes is well described. However, less is known about the appropriateness of AMT in nursing home residents. Therefore, the Check of APpropriaTeness of antimicrobial therapy in nursing homes (CAPTAIN) study aimed to assess both prevalence and appropriateness of AMT in Belgian nursing homes.

Methods

In a prospective, observational, point prevalence study, researchers documented prevalence and identified potentially inappropriate prescriptions (PIPs) by evaluating accordance of AMT with national guidelines. The severity of inappropriateness was assessed by a modified Delphi expert panel.

Results

Eleven nursing homes, including 1178 residents, participated in this study. On the survey day, 8.0% of residents took systemic AMT, primarily for urinary tract infections (54.2%), respiratory tract infections (36.5%), and skin and skin-structure infections (6.3%). About half of these prescriptions were used in prophylaxis (52.1%). Registration of indication and stop date was missing in 58.3% and 56.3% of AMTs, respectively. In 89.6% of the systemic AMTs, at least one discordance with national guidelines was identified, resulting in a total of 171 PIPs, with 49 unique PIPs. Of all unique PIPs, 26.5% were assessed with a high severity score (≥4). According to the expert panel, most inappropriate practice was starting AMT for cough without other symptoms. Inappropriate timing of time-dependent AMTs was common, but assessed as 'moderately severe'. One-third of systemic AMT exceeded the recommended duration.

Conclusions

AMT in nursing homes is often not prescribed according to national guidelines, highlighting the need for future interventions to promote the rational use of AMT in this setting.

U.S. primary care physician perceptions on barriers to providing guideline-driven care for UTI and recurrent UTI: a qualitative study

BACKGROUND

Urinary tract infections (UTI) affect almost two-thirds of all women during their lives and many experience recurrent infections. There are evidence-based guidelines from multiple international societies for evaluation and treatment; however, recent claims-based analyses have demonstrated that adherence to these guidelines is poor. This study seeks to understand the barriers experienced by U.S. primary care providers (PCPs) to providing guideline-based care for UTI and recurrent UTI (rUTI).

METHODS

Semi-structured interviews of 18 PCPs, recruited from the greater Los Angeles area, examined real-world clinical management of UTI/rUTI episodes, decisions to refer to subspecialty care, and resources guiding counseling and management. Grounded theory methodology served to analyze interview transcripts and identify preliminary and major themes.

RESULTS

Participants expressed the desire to obtain urine cultures for each cystitis episode, but felt pressured to make compromises by patient demands or barriers to care. PCPs had lower thresholds to empirical treatment if patients had a history of rUTIs, were elderly, or declined evaluation. Laboratory data was minimally utilized in clinical decision-making: urinalyses were infrequently considered when interpreting culture data. PCPs treated a broad set of urologic and non-urologic symptoms as UTI, even with negative cultures. PCPs did not feel comfortable initiating UTI prophylaxis, instead seeking specialist evaluation for anatomic causes. They were unaware of management guidelines, typically utilizing UpToDate® as their primary resource. Few evidence-based UTI prevention interventions were recommended by providers.

CONCLUSIONS

Low availability of succinct and clear professional guidelines are substantial barriers to appropriate UTI/rUTI care. Poor useability of clinical guidance documents results in substantial confusion about the role of preventative measures and additional diagnostic testing. Difficulties in patient access to care providers lead to expectations for presumptive treatment. Future studies are needed to determine if improved educational materials for providers and/or management algorithms can improve guideline concordance of UTI management.

Recurrent UTI in Women-Risk Factors and Management

Urinary tract infections (UTIs) are common in women; more than 50% of women will be diagnosed with a UTI in her lifetime. Many of these women will go on to develop recurrent UTI. Nevertheless, evidence-based prevention of recurrent UTI is under-utilized. Here, the authors provide detailed practical advice on UTI prevention with a thorough review of the evidence. Non-antibiotic prevention measures discussed include increased fluid intake, vaginal estrogen therapy, methenamine, and cranberry. Antibiotic prophyalxis for carefully selected patients is also discussed.

Urinary Tract Infection Diagnostic and Management Considerations in People with Spinal Cord Injury and Neurogenic Bladder

Urinary tract infections (UTIs) are common complications in people with neurogenic bladder. Prevention, diagnosis, and treatment are challenging for several reasons, including a high prevalence of asymptomatic bacteriuria and catheter use, frequent ambiguous nonlocalizing signs and symptoms, increased risk for complications and difficult-to-treat pathogens, and a lack of effective preventative methods. Current research aims to improve elicitation and evaluation of signs and symptoms, implement algorithms to avoid urine cultures in asymptomatic patients and use appropriate antibiotics for UTI, and identify novel effective prevention methods.

Factors associated with symptomatic urinary tract infection in persons with spinal cord lesions who perform clean intermittent catheterization with single-use catheters

OBJECTIVES

To investigate factors associated with symptomatic urinary tract infection (sUTI) in persons with chronic spinal cord lesion (SCL) who were using single-use catheters for intermittent self-catheterization (ISC).

METHODS

Among respondents to an internet survey on the burden of illness on persons with SCL who were considered to be able to perform ISC, 111 persons using single-use catheters were included to examine factors associated with self-reported sUTI by univariate as well as multivariable analysis.

RESULTS

The incidence of sUTI was significantly higher in males than in females (56.9% vs. 31.6%, p = .011), persons with stocks of antibiotics than those without it (82.9% vs. 28.6%, p < .011), and persons with more frequent bleeding during catheterization than those with less frequent bleeding (100% vs. 46.5%, p = .036). The incidence did not significantly differ between respective groups when various variables were evaluated by other characteristics of the participants, adherence to ISC procedures, and complications. On multivariable analysis, male gender and stocks of antibiotics were significant independent factors for sUTI.

CONCLUSIONS

Male gender and stocks of antibiotics were associated with sUTI in persons with SCL who were performing ISC with single-use catheters.

Cost-effectiveness of methenamine hippurate compared with antibiotic prophylaxis for the management of recurrent urinary tract infections in secondary care: a multicentre, open-label, randomised, non-inferiority trial

OBJECTIVES

To estimate the cost-effectiveness of methenamine hippurate compared with antibiotic prophylaxis in the management of recurrent urinary tract infections.

DESIGN

Multicentre, open-label, randomised, non-inferiority trial.

SETTING

Eight centres in the UK, recruiting from June 2016 to June 2018.

PARTICIPANTS

Women aged ≥18 years with recurrent urinary tract infections, requiring prophylactic treatment.

INTERVENTIONS

Women were randomised to receive once-daily antibiotic prophylaxis or twice-daily methenamine hippurate for 12 months. Treatment allocation was not masked and crossover between arms was allowed.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary economic outcome was the incremental cost per quality-adjusted life year (QALY) gained at 18 months. All costs were collected from a UK National Health Service perspective. QALYs were estimated based on responses to the EQ-5D-5L administered at baseline, 3, 6, 9, 12 and 18 months. Incremental costs and QALYs were estimated using an adjusted analysis which controlled for observed and unobserved characteristics. Stochastic sensitivity analysis was used to illustrate uncertainty on a cost-effectiveness plane and a cost-effectiveness acceptability curve. A sensitivity analysis, not specified in the protocol, considered the costs associated with antibiotic resistance.

RESULTS

Data on 205 participants were included in the economic analysis. On average, methenamine hippurate was less costly (-£40; 95% CI: -684 to 603) and more effective (0.014 QALYs; 95% CI: -0.05 to 0.07) than antibiotic prophylaxis. Over the range of values considered for an additional QALY, the probability of methenamine hippurate being considered cost-effective ranged from 51% to 67%.

CONCLUSIONS

On average, methenamine hippurate was less costly and more effective than antibiotic prophylaxis but these results are subject to uncertainty. Methenamine hippurate is more likely to be considered cost-effective when the benefits of reduced antibiotic use were included in the analysis.

TRIAL REGISTRATION NUMBER

ISRCTN70219762.

A review of the mechanisms that confer antibiotic resistance in pathotypes of E. coli

The dissemination of antibiotic resistance in Escherichia coli poses a significant threat to public health worldwide. This review provides a comprehensive update on the diverse mechanisms employed by E. coli in developing resistance to antibiotics. We primarily focus on pathotypes of E. coli (e.g., uropathogenic E. coli) and investigate the genetic determinants and molecular pathways that confer resistance, shedding light on both well-characterized and recently discovered mechanisms. The most prevalent mechanism continues to be the acquisition of resistance genes through horizontal gene transfer, facilitated by mobile genetic elements such as plasmids and transposons. We discuss the role of extended-spectrum β-lactamases (ESBLs) and carbapenemases in conferring resistance to β-lactam antibiotics, which remain vital in clinical practice. The review covers the key resistant mechanisms, including: 1) Efflux pumps and porin mutations that mediate resistance to a broad spectrum of antibiotics, including fluoroquinolones and aminoglycosides; 2) adaptive strategies employed by E. coli, including biofilm formation, persister cell formation, and the activation of stress response systems, to withstand antibiotic pressure; and 3) the role of regulatory systems in coordinating resistance mechanisms, providing insights into potential targets for therapeutic interventions. Understanding the intricate network of antibiotic resistance mechanisms in E. coli is crucial for the development of effective strategies to combat this growing public health crisis. By clarifying these mechanisms, we aim to pave the way for the design of innovative therapeutic approaches and the implementation of prudent antibiotic stewardship practices to preserve the efficacy of current antibiotics and ensure a sustainable future for healthcare.

Outcomes of Bladder Washout for the Treatment of Recurrent Urinary Tract Infections After Renal Transplantation

Background Current literature suggests that anywhere from 2.9-27% of renal transplant recipients (RTR) will develop recurrent urinary tract infections (UTIs) (≥2 UTIs over six months or ≥3 UTIs over 12 months). Recurrent UTIs are of particular importance to RTR given its increased risk for allograft fibrosis and overall patient survival. Alternative solutions are needed for the management of recurrent UTIs, especially given the vulnerability of RTR to UTIs. We hypothesize that bladder washout (BW) reduces the incidence and recurrence of UTIs in RTR. Methods This is a retrospective study evaluating the utility of BW procedures on RTR diagnosed with recurrent UTIs between December 2013 and July 2021 at a single center. Results A total of 106 patients were included in the study with a total of 118 BW performed. 69% of patients were successfully treated with BW, meaning they no longer met the criteria for recurrent UTIs (<1 UTI) in the six-month post-BW period. The mean number of UTIs was 2.76 (range 2-7) before the BW and 1.16 (range 0-5) after the BW. On average, there were 1.60 fewer UTIs in the post-BW period compared to the pre-BW period (p<0.0001). There is no statistically significant difference in success rates stratified by bacterial class (p=1) or antimicrobial resistance class (p=0.6937). Conclusion BW decreased the incidence of UTIs in the six-month post-operative period as nearly 70% of patients did not have UTI recurrence. This data provides evidence that BW may have utility in transplant recipients with recurrent UTIs. We hope this will stimulate further prospective randomized studies in this area.

Methenamine for urinary tract infection prophylaxis: A systematic review

Urinary tract infections (UTIs) commonly affect many patient populations. Recurrent UTIs (rUTIs) can be particularly problematic and lead to potential hospitalizations, multiple antibiotic courses, and have a potential negative impact on quality of life. To prevent UTIs, antibiotics are frequently used for prophylaxis; however, antibiotic prophylaxis has notable untoward consequences including but not limited to potential adverse effects and development of antibiotic resistance. Methenamine, an antiseptic agent initially available in 1967, has re-emerged as a potential option for UTI prophylaxis in various populations, including older adults and renal transplant recipients. The objective of this systematic review was to evaluate the clinical effectiveness and safety of methenamine for UTI prophylaxis. A systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance was performed. A PubMed, Embase, and Cochrane library search was conducted to identify relevant English-language studies evaluating methenamine for UTI prophylaxis including randomized controlled trials, case-control studies, and meta-analyses through June 2023. Articles were excluded if the studies did not primarily describe or evaluate methenamine for UTI prophylaxis, were commentaries/viewpoints articles, point prevalence studies, review articles, studies that evaluated methenamine used with another agent, and any duplicate publications from searched databases. A total of 11 articles were identified for inclusion. This systematic review suggests methenamine generally appears to be an effective and well-tolerated antibiotic-sparing option for UTI prophylaxis. Furthermore, the pharmacology, dosage and formulation, warnings, precautions, and safety considerations of methenamine that provide potential clinical considerations regarding its use for UTI prophylaxis are described. Further studies are needed to evaluate the clinical utility of methenamine for UTI prophylaxis.

New avenue of diagnostic stewardship: procedural stewardship for recurrent urinary tract infections in female patients

Introduction

Societal guidelines offer a weak recommendation to perform cystoscopy for female patients with recurrent urinary tract infections (rUTI) of advanced age and/or with high-risk features. These guidelines lack the support of robust data and are instead based on expert opinion. In this retrospective cohort study, we aim to determine the utility of cystoscopy in patients with and without high-risk features for rUTI.

Materials and methods

We identified 476 women who underwent cystoscopy for the evaluation of rUTI at a single tertiary academic medical center from May 1, 2015 and March 15, 2021. Patients were excluded if they had a competing indication for cystoscopy. Risk factors, demographic information, cystoscopic findings, and patient outcomes were analyzed.

Results

192 (41.1%) were classified as having complicated UTI. We identified six patients (1.3%) with findings that prompted management to significantly impact patient outcomes. All six patients had high-risk features. 14 patients (3.0%) were found to have mucosal abnormalities prompting biopsy, three of which required general anesthesia. All 14 biopsies were ultimately benign.

Conclusions

Our findings demonstrate a low diagnostic yield and increased risk exposure for women undergoing cystoscopy for the evaluation of complicated rUTI. Additionally, our observations support prior studies indicating that cystoscopy has limited utility in the evaluation of rUTI without high-risk features.

Factors associated with urinary tract infection in the early phase after performing intermittent catheterization in individuals with spinal cord injury: a retrospective study

Objectives

To investigate the occurrence rate of urinary tract infections (UTIs) in the early phase after performing intermittent catheterization (IC) and to explore the possible factors associated with UTIs after performing IC among people with spinal cord injury (SCI).

Setting

An inpatient rehabilitation department of a teaching hospital in China.

Design

Retrospective chart review.

Methods

A retrospective chart review was carried out for traumatic and non-traumatic SCI patients after performing IC during their inpatient stay. Demographic information, comorbidity of diabetes, urine analysis results before IC, method of IC (sterile or clean), use of bladder irrigation, cessation of IC and its reasons, and UTI events were collected.

Results

A total of 183 adult individuals were included, of which 60 (32.8%) of them were women. The median age was 49.0 years. The median time post-injury was 2 months. The overall occurrence rate of UTI after performing IC was 1.31 (95% confidence intervals: 0.96-1.77) events per 100 days. Sixty-nine (37.7%) patients discontinued IC during hospitalization, and UTIs were the leading reason for cessation (50.7%). Female sex, use of antibiotics for infections other than UTI, and use of bladder irrigation were found to be associated with a lower occurrence rate of UTI in the early phase after performing IC, with an odds ratio of 0.38 (p = 0.019), 0.20 (p = 0.022), and 0.24 (p < 0.001), respectively.

Conclusion

UTI after performing IC is prevalent among people with SCI. The study indicated that antibiotic prophylaxis and routine bladder irrigation might be associated with the reduction in UTI in the early phase after performing IC. Further research is needed to provide more evidence.

Urinary tract infections: a review of the current diagnostics landscape

Urinary tract infections are the most common bacterial infections worldwide. Infections can range from mild, recurrent (rUTI) to complicated (cUTIs), and are predominantly caused by uropathogenic Escherichia coli (UPEC). Antibiotic therapy is important to tackle infection; however, with the continued emergence of antibiotic resistance there is an urgent need to monitor the use of effective antibiotics through better stewardship measures. Currently, clinical diagnosis of UTIs relies on empiric methods supported by laboratory testing including cellular analysis (of both human and bacterial cells), dipstick analysis and phenotypic culture. Therefore, development of novel, sensitive and specific diagnostics is an important means to rationalise antibiotic therapy in patients. This review discusses the current diagnostic landscape and highlights promising novel diagnostic technologies in development that could aid in treatment and management of antibiotic-resistant UTIs.

Risk factors for urinary tract infections associated with lower quality of life among intermittent catheter users

BACKGROUND

Evidence shows that intermittent catheterisation (IC) for bladder emptying is linked to urinary tract infections (UTIs) and poor quality of life (QoL).

AIM

To investigate the association between UTI risk factors and QoL and patient-reported UTIs respectively.

METHODS

A survey was distributed to IC users from 13 countries.

FINDINGS

Among 3464 respondents, a significantly poorer QoL was observed when experiencing blood in the urine, residual urine, bowel dysfunction, recurrent UTIs, being female, and applying withdrawal techniques. A lower UTI risk was found when blood was not apparent in urine (RR: 0.63; 95% CI: 0.55-0.71), the bladder was perceived empty (RR: 0.83; 95% CI: 0.72-0.96), not having bowel dysfunction (RR: 0.86; 95% CI: 0.76-0.98), and being male (RR: 0.70; 95% CI: 0.62-0.79).

CONCLUSION

This study underlines the importance of risk factors and their link to QoL and UTIs, highlighting the need for addressing symptoms before UTIs become problematic.

Nitrofurantoin-Induced Lung Injury: A Reminder of an Overlooked Threat

Nitrofurantoin is a commonly prescribed antibiotic for urinary tract infection (UTI) treatment and prophylaxis. Although relatively rare, nitrofurantoin can cause a spectrum of lung injuries, from acute hypersensitivity reactions that might be fatal to chronic reactions involving fibrosis. Therefore, treating physicians' awareness and regular monitoring is essential for early recognition, drug withdrawal, avoiding unnecessary treatment, and preventing irreversible fibrosis. Here, we report the case of a 77-year-old woman who had been hospitalized with interstitial lung disease due to chronic nitrofurantoin therapy. Despite the severity of symptoms and the extent of radiological lung involvement, she returned to her clinical and radiological baseline shortly following the drug cessation.

A suspension of inactivated bacteria used for vaccination against recurrent urinary tract infections increases the phagocytic activity of murine macrophages

Background

Urinary tract infections are a major cause of the consumption of antibiotics in humans.

Methods

We studied the effect of a vaccine (StroVac®, containing inactivated bacteria and used to prevent recurrent urinary tract infections) licensed in Germany on the release of pro-inflammatory cytokines and the phagocytosis of Escherichia (E.) coli in primary murine macrophages and the macrophage cell line J774A.1.

Results

StroVac® increased the release of the cytokines TNF-α, IL-6, IL-12/23 p40, and IL-1β and stimulated the phagocytosis of E. coli in a dose-dependent manner. This effect was independent of LPS as shown by the use of macrophages isolated from LPS-resistant C3H/HeJ mice. At concentrations up to 30 mg/l it was not toxic to bacteria or eukaryotic cells.

Conclusion

StroVac® does not only act via the adaptive but also by stimulating the innate immune system. This stimulation may help to build trained innate immunity against bacterial pathogens involved in recurrent urinary tract infections.

Nitrofurantoin: properties and potential in treatment of urinary tract infection: a narrative review

Nitrofurantoin (NF), a wide-spectrum antibiotic accessible since 1953, is utilized widely to treat urinary tract infections as it usually stays active against drug-resistant uropathogen. The use of Nitrofurantoin has increased exponentially since new guidelines have repositioned it as first-line therapy for uncomplicated lower urinary tract infection (UTI). To, although fluoroquinolones are usually used to re-evaluate the first- and second-line therapies for treating uncomplicated UTI, their level of utilization is thought to be inappropriately excessive and will eventually have a detrimental impact; thus, we hypothesize that NF might be the best choice for this condition, because of its low frequency of utilization and its high susceptibility in common UTI pathogens. It can be concluded from this review that NF can be considered as the most effective drug in the treatment of acute urinary infection, but due to the long-term side effects of this drug, especially in elderly patients, it is essential to introduce some criteria for prescribing NF in cases of chronic UTI.

QUIRMIA-A Phenotype-Based Algorithm for the Inference of Quinolone Resistance Mechanisms in Escherichia coli

OBJECTIVES

Quinolone resistance in Escherichia coli occurs mainly as a result of mutations in the quinolone-resistance-determining regions of gyrA and parC, which encode the drugs' primary targets. Mutational alterations affecting drug permeability or efflux as well as plasmid-based resistance mechanisms can also contribute to resistance, albeit to a lesser extent. Simplifying and generalizing complex evolutionary trajectories, low-level resistance towards fluoroquinolones arises from a single mutation in gyrA, while clinical high-level resistance is associated with two mutations in gyrA plus one mutation in parC. Both low- and high-level resistance can be detected phenotypically using nalidixic acid and fluoroquinolones such as ciprofloxacin, respectively. The aim of this study was to develop a decision tree based on disc diffusion data and to define epidemiological cut-offs to infer resistance mechanisms and to predict clinical resistance in E. coli. This diagnostic algorithm should provide a coherent genotype/phenotype classification, which separates the wildtype from any non-wildtype and further differentiates within the non-wildtype.

METHODS

Phenotypic susceptibility of 553 clinical E. coli isolates towards nalidixic acid, ciprofloxacin, norfloxacin and levofloxacin was determined by disc diffusion, and the genomes were sequenced. Based on epidemiological cut-offs, we developed a QUInolone Resistance Mechanisms Inference Algorithm (QUIRMIA) to infer the underlying resistance mechanisms responsible for the corresponding phenotypes, resulting in the categorization as "susceptible" (wildtype), "low-level resistance" (non-wildtype) and "high-level resistance" (non-wildtype). The congruence of phenotypes and whole genome sequencing (WGS)-derived genotypes was then assigned using QUIRMIA- and EUCAST-based AST interpretation.

RESULTS

QUIRMIA-based inference of resistance mechanisms and sequencing data were highly congruent (542/553, 98%). In contrast, EUCAST-based classification with its binary classification into "susceptible" and "resistant" isolates failed to recognize and properly categorize low-level resistant isolates.

CONCLUSIONS

QUIRMIA provides a coherent genotype/phenotype categorization and may be integrated in the EUCAST expert rule set, thereby enabling reliable detection of low-level resistant isolates, which may help to better predict outcome and to prevent the emergence of clinical resistance.

Recurrent Urinary Tract Infection in Adult Patients, Risk Factors, and Efficacy of Low Dose Prophylactic Antibiotics Therapy

BACKGROUND

Recurrent urinary tract infection (UTI) occurs in sizable percentages of patients after a single episode and is a frequent cause of primary healthcare visits and hospital admissions, accounting for up to one quarter of emergency department visits. We aim to describe the pattern of continuous antibiotic prophylaxis prescription for recurrent urinary tract infections, in what group of adult patients they are prescribed and their efficacy.

METHODS

A retrospective chart review of all adult patients diagnosed with single and recurrent symptomatic urinary tract infection in the period of January 2016 to December 2018.

RESULTS

A total of 250 patients with a single UTI episode and 227 patients with recurrent UTI episodes were included. Risk factors for recurrent UTI included diabetes mellitus, chronic renal disease, and use of immunosuppressive drugs, renal transplant, any form of urinary tract catheterization, immobilization and neurogenic bladder. E. coli infections were the most prevalent organism in patients with UTI episodes. Prophylactic antibiotics were given to 55% of patients with UTIs, Nitrofurantoin, Bactrim or amoxicillin clavulanic acid. Post renal transplant is the most frequent reason to prophylaxis antibiotics (44%). Bactrim was more prescribed in younger patients (P < 0.001), in post-renal transplantation (P < 0.001) and after urological procedures (P < 0.001), while Nitrofurantoin was more prescribed in immobilized patients (P = 0.002) and in patients with neurogenic bladder (P < 0.001). Patients who received continuous prophylactic antibiotics experienced significantly less episodes of urinary tract infections (P < 0.001), emergency room visits and hospital admissions due to urinary tract infections (P < 0.001).

CONCLUSION

Despite being effective in reducing recurrent urinary tract infection rate, emergency room visits and hospital admissions due to UTI, continuous antibiotic prophylaxis was only used in 55% of patients with recurrent infections. Trimethoprim/sulfamethoxazole was the most frequently used prophylactic antibiotic. Urology and gynecological referral were infrequently requested as part of the evaluation process for patients with recurrent UTI. There was a lack of use of other interventions such as topical estrogen in postmenopausal women and documentation of education on non-pharmacological methods to decrease urinary tract infections.

Time trade-off study to establish utility decrements in individuals with a spinal cord injury who perform intermittent catheterisation

AIMS

To generate utility decrements for three attributes associated with catheterisation for individuals with a spinal cord injury (SCI): the process of catheterisation, the physical impact of urinary tract infections (UTIs) and worry associated with hospitalisation.

MATERIALS AND METHODS

Health state vignettes comprising various levels of the three attributes were developed. Two cohorts of respondents, corresponding to people with SCIs and a sample broadly representative of the UK population, were presented with nine vignettes (three vignettes for the mild, moderate and severe health states in addition to a random set of six vignettes). It was assumed no or a nominal decrement was associated with the mild health state. Utility decrements were derived from analysing the data obtained from the online time trade-off (TTO). A proportion of the SCI cohort (n = 57) also completed the EQ-5D-5L questionnaire.

RESULTS

Utility decrements were generated using statistical models for the general population (n = 358), the SCI population (n = 48) and the two populations combined (merged model, n = 406). Results from the two cohorts showed minimal differences. For the merged model, SCI status was not statistically significant. All interaction terms, excluding SCI and the severe level of the physical attribute, were not statistically significant. Compared to the mild level, the greatest utility decrement calculated was the severe level of the emotional (worry) attribute (0.09, p < 0.001) for the SCI population. A significant decrement of 0.02 (p <0.001) was calculated for the moderate level of the emotional attribute for all models. The mean utility score for those with SCI having completed the EQ-5D-5L was 0.371.

LIMITATIONS

Modest sample size of respondents from the SCI population (n = 48).

CONCLUSIONS

Worry associated with hospitalisation had the greatest impact on patients' health-related quality of life (HRQoL). The catheterisation process, such as the lubrication and repositioning of the catheter, also impacted on patients' HRQoL.

The clinical implications of bacterial pathogenesis and mucosal immunity in chronic urinary tract infection

Urinary tract infections (UTIs) exert a significant health and economic cost globally. Approximately one in four people with a previous history of UTI continue to develop recurrent or chronic infections. Research on UTI has primarily concentrated on pathogen behavior, with the focus gradually shifting to encompass the host immune response. However, these are centered on mouse models of Escherichia coli infection, which may not fully recapitulate the infective etiology and immune responses seen in humans. The emerging field of the urobiome also inadvertently confounds the discrimination of true UTI-causing pathogens from commensals. This review aims to present a novel perspective on chronic UTI by linking microbiology with immunology, which is commonly divergent in this field of research. It also describes the challenges in understanding chronic UTI pathogenesis and the human bladder immune response, largely conjectured from murine studies. Lastly, it outlines the shortcomings of current diagnostic methods in identifying individuals with chronic UTI and consequently treating them, potentially aggravating their disease due to mismanagement of prior episodes. This discourse highlights the need to consider these knowledge gaps and encourages more relevant studies of UTIs in humans.

Urinary Tract Infection Frequency and Prescription Prophylaxis in Females and Males with Recurrent Urinary Tract Infection

Females and males with recurrent urinary tract infections may receive prescription prophylaxis to reduce the infection frequency. Little is known about how prescription prophylaxis differs between patients meeting and exceeding the minimum threshold for recurrent urinary tract infections. The objectives of this study were to estimate the association between infection frequency and receipt of prescription prophylaxis and describe the type of prescription prophylaxis initiated. This observational study used de-identified fully-insured commercial insurance data from the Midwest from 2003-2016 to identify females and males under age 64 with recurrent urinary tract infections. The patients were categorized as having three or more urinary tract infections in twelve months or only two infections in six months. Multiple logistic regression models were used to determine the association between the infection frequency and receipt of prophylaxis. The frequency of the type of prophylaxis initiated was measured. The odds of receiving prophylaxis were greater in the females and males with three or more infections compared to the patients with only two infections. Estrogen prophylaxis was initiated at a higher rate in females aged 45-63 with two infections than the females with three or more infections. Prescription prophylaxis in females and males with recurrent urinary tract infections differs between those meeting and exceeding the minimum frequency threshold.

Evasion of toll-like receptor recognition by Escherichia coli is mediated via population level regulation of flagellin production

Uropathogenic Escherichia coli is a major cause of urinary tract infections. Analysis of the innate immune response in immortalized urothelial cells suggests that the bacterial flagellar subunit, flagellin, is key in inducing host defenses. A panel of 48 clinical uro-associated E. coli isolates recovered from either cystitis, pyelonephritis asymptomatic bacteriuria (ABU) or UTI-associated bacteraemia infections were characterized for motility and their ability to induce an innate response in urothelial cells stably transfected with a NF-κB luciferase reporter. Thirty-two isolates (67%) were identified as motile with strains recovered from cystitis patients exhibiting an uneven motility distribution pattern; seven of the cystitis isolates were associated with a  > 5-fold increase in NF-κB signaling. To explore whether the NF-κB signaling response reflected antigenic variation, flagellin was purified from 14 different isolates. Purified flagellin filaments generated comparable NF-κB signaling responses, irrespective of either the source of the isolate or H-serotype. These data argued against any variability between isolates being related to flagellin itself. Investigations also argued that neither TLR4 dependent recognition of bacterial lipopolysaccharide nor growth fitness of the isolates played key roles in leading to the variable host response. To determine the roles, if any, of flagellar abundance in inducing these variable responses, flagellar hook numbers of a range of cystitis and ABU isolates were quantified. Images suggested that up to 60% of the isolate population exhibited flagella with the numbers averaging between 1 and 2 flagella per bacterial cell. These data suggest that selective pressures exist in the urinary tract that allow uro-associated E. coli strains to maintain motility, but exploit population heterogeneity, which together function to prevent host TLR5 recognition and bacterial killing.

Exploring the in situ evolution of nitrofurantoin resistance in clinically derived uropathogenic Escherichia coli isolates

BACKGROUND

Nitrofurantoin has been re-introduced as a first-choice antibiotic to treat uncomplicated acute urinary tract infections in England and Wales. Highly effective against common uropathogens such as Escherichia coli, its use is accompanied by a low incidence (<10%) of antimicrobial resistance. Resistance to nitrofurantoin is predominantly via the acquisition of loss-of-function, step-wise mutations in the nitroreductase genes nfsA and nfsB.

OBJECTIVE

To explore the in situ evolution of NitR in E. coli isolates from 17 patients participating in AnTIC, a 12-month open label randomized controlled trial assessing the efficacy of antibiotic prophylaxis in reducing urinary tract infections (UTIs) incidence in clean intermittent self-catheterizing patients.

METHODS

The investigation of NitR evolution in E. coli used general microbiology techniques and genetics to model known NitR mutations in NitSE. coli strains.

RESULTS

Growth rate analysis identified a 2%-10% slower doubling time for nitrofurantoin resistant strains: NitS: 20.8 ± 0.7 min compared to NitR: 23 ± 0.8 min. Statistically, these data indicated no fitness advantage of evolved strains compared to the sensitive predecessor (P-value = 0.13). Genetic manipulation of E. coli to mimic NitR evolution, supported no fitness advantage (P-value = 0.22). In contrast, data argued that a first-step mutant gained a selective advantage, at sub-MIC (4-8 mg/L) nitrofurantoin concentrations.

CONCLUSION

Correlation of these findings to nitrofurantoin pharmacokinetic data suggests that the low incidence of E. coli NitR, within the community, is driven by urine-based nitrofurantoin concentrations that selectively inhibit the growth of E. coli strains carrying the key first-step loss-of-function mutation.

A survey of clinical practice concerning long-term follow-up of neurogenic lower urinary tract dysfunction due to spinal cord injury in Italy

CONTEXT/OBJECTIVE

This study aimed to assess the clinical practice for long-term follow-up (FU) of neurogenic lower urinary tract dysfunction (NLUTD) due to spinal cord injury (SCI) in Italy and compare this practice with the clinical practice in other countries and with the international guidelines.

DESIGN

Data concerning the long-term urological FU of individuals with SCI were collected using a questionnaire and analyzed by means of descriptive and inferential statistics.

SETTING

Twenty-one Italian centers following SCI patients.

PARTICIPANTS

One physician at each center (either a permanent staff member or chief).

OUTCOME MEASURES

Questions addressed the treatment of urinary tract infections (UTI), frequency of visits, urinary tract imaging examinations and urodynamic tests (UD), distinguishing between suprasacral and sacral SCI.

RESULTS

Nineteen out of 21 centers completed the survey. In most centers, patients were recommended to undergo a visit and an ultrasound examination of urinary tract (UT) at least once a year. While the median interval between FU visits was identical (12 months) for individuals with suprasacral and sacral SCI, the two interval distributions were significantly different (suprasacral SCI: min-max 4-18, IQR = 6; sacral SCI: min-max 6-24; IQR = 8.5; P = 0.02), showing people with suprasacral SCI are followed up more often. Approximately 80% of the surveyed centers performed scheduled UD, with a yearly median frequency of 12 months (range 6-36) for patients with suprasacral SCI, as compared to a median frequency of 18 months for sacral SCI (range 0-36, P = 0.04). VideoUD and antibiotic prophylaxis for recurrent UTIs are carried out only by urologists in 63% and 47.4% of the centers, respectively. Overall, Italian centers share common strategies that compare to standards, including yearly visits, yearly UT examinations and stricter follow-up of people with suprasacral SCI, but may not have standard protocols for antibiotic prophylaxis of UTI, and in few cases control visits and UD are carried out too often.

CONCLUSIONS

Even though most Italian centers follow up patients with NLUTD secondary to SCI according to international guidelines, heterogeneity in frequency of FU examinations still exists. A tailored approach to the SCI patient that minimizes unnecessary examinations and groups different tests in a single access could improve patients' compliance with FU and reduce costs for the Health system.

Low Ciprofloxacin Concentrations Select Multidrug-Resistant Mutants Overproducing Efflux Pumps in Clinical Isolates of Pseudomonas aeruginosa

Low antibiotic concentrations present in natural environments are a severe and often neglected threat to public health. Even if they are present below their MICs, they may select for antibiotic-resistant pathogens. Notably, the minimal subinhibitory concentrations that select resistant bacteria, and define the respective sub-MIC selective windows, differ between antibiotics. The establishment of these selective concentrations is needed for risk-assessment studies regarding the presence of antibiotics in different habitats. Using short-term evolution experiments in a set of 12 Pseudomonas aeruginosa clinical isolates (including high-risk clones with ubiquitous distribution), we have determined that ciprofloxacin sub-MIC selective windows are strain specific and resistome dependent. Nonetheless, in all cases, clinically relevant multidrug-resistant (MDR) mutants emerged upon exposure to low ciprofloxacin concentrations, with these concentrations being below the levels reported in ciprofloxacin-polluted natural habitats where P. aeruginosa can be present. This feature expands the conditions and habitats where clinically relevant quinolone-resistant mutants can emerge. In addition, we established the lowest concentration threshold beyond which P. aeruginosa, regardless of the strain, becomes resistant to ciprofloxacin. Three days of exposure under this sub-MIC "risk concentration" led to the selection of MDR mutants that displayed resistance mechanisms usually ascribed to high selective pressures, i.e., the overproduction of the efflux pumps MexCD-OprJ and MexEF-OprN. From a One-Health viewpoint, these data stress the transcendent role of low drug concentrations, which can be encountered in natural ecosystems, in aggravating the antibiotic resistance problem, especially when it comes to pathogens of environmental origin. IMPORTANCE It has been established that antibiotic concentrations below MICs can select antibiotic-resistant pathogens, a feature of relevance for analyzing the role of nonclinical ecosystems in antibiotic resistance evolution. The range of concentrations where this selection occurs defines the sub-MIC selective window, whose width depends on the antibiotic. Herein, we have determined the ciprofloxacin sub-MIC selective windows of a set of Pseudomonas aeruginosa clinical isolates (including high-risk clones with worldwide distribution) and established the lowest concentration threshold, notably an amount reported to be present in natural ecosystems, beyond which this pathogen acquires resistance. Importantly, our results show that this ciprofloxacin sub-MIC selects for multidrug-resistant mutants overproducing clinically relevant efflux pumps. From a One-Health angle, this information supports that low antimicrobial concentrations, present in natural environments, may have a relevant role in worsening the antibiotic resistance crisis, particularly regarding pathogens with environmental niches, such as P. aeruginosa.

Reducing infection risk in multiple sclerosis and neuromyelitis optica spectrum disorders: a Brazilian reference center's approach

BACKGROUND

Multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD) are the most common autoimmune diseases of the central nervous system (CNS). They present chronic relapsing courses that demand treatment with disease-modifying drugs (DMDs) to prevent inflammatory activity. Disease-modifying drugs lead to immunomodulation or immunosuppression through diverse mechanisms (e.g., shifting lymphocyte and cytokine profile, suppressing specific lymphocyte subpopulations). Thus, patients are more prone to infectious complications and associated worsening of disease.

OBJECTIVE

To present feasible strategies for mitigating the infection risk of MS and NMOSD treated patients.

METHODS

Targeted literature review concerning the management of infection risk with an emphasis on vaccination, therapy-specific measures, and particularities of the Brazilian endemic infectious diseases' scenario.

CONCLUSION

We propose a vaccination schedule, infectious screening routine, and prophylactic measures based on the current scientific evidence. Awareness of emergent tropical diseases is necessary due to evidence of demyelinating events and possible parainfectious cases of MS and NMOSD.

Gold nanocluster adjuvant enables the eradication of persister cells by antibiotics and abolishes the emergence of resistance

Persister cells are responsible for relapses of infections common in cystic fibrosis and chronic suppurative otitis media (CSOM). Yet, there are no Food and Drug Administration (FDA) approved antibiotics to eradicate persister cells. Frustratingly, the global preclinical bacterial pipeline does not contain antibacterial agents targeting persister cells. Therefore, we report a nontraditional antimicrobial chemotherapy strategy based on gold nanoclusters adjuvant to eradicate persister cells by existing antibiotics belonging to that different class. Compared to killing with antibiotics alone, combining antibiotics and AuNC@CPP sterilizes persister cells and biofilms. Enhanced killing of up to 4 orders of magnitude in a validated mouse model of CSOM with Pseudomonas aeruginosa infection was observed when combining antibiotics and AuNC@CPP, informing a potential approach to improve the treatment of CSOM. We established that the mechanism of action of AuNC@CPP is due to disruption of the proton gradient and membrane hyperpolarization. The method presented here could compensate for the lack of new antibiotics to combat persister cells. This method could also benefit the current effort to slow resistance development because AuNC@CPP abolished the emergence of drug-resistant strains induced by antibiotics.

Methenamine hippurate compared with antibiotic prophylaxis to prevent recurrent urinary tract infections in women: the ALTAR non-inferiority RCT

BACKGROUND

Daily, low-dose antibiotic prophylaxis is the current standard care for women with recurrent urinary tract infection. Emerging antimicrobial resistance is a global health concern, prompting research interest in non-antibiotic agents such as methenamine hippurate, but comparative data on their efficacy and safety are lacking.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of methenamine hippurate (Hiprex®; Mylan NV, Canonsburg, PA, USA) compared with current standard care (antibiotic prophylaxis) for recurrent urinary tract infection prevention in adult women.

DESIGN

Multicentre, pragmatic, open-label, randomised, non-inferiority trial of 12 months' treatment with the allocated intervention, including an early, embedded qualitative study and a 6-month post-treatment observation phase. The predefined non-inferiority margin was one urinary tract infection per person-year.

SETTING

Eight UK NHS secondary care sites.

PARTICIPANTS

A total of 240 adult women with recurrent urinary tract infection requiring preventative treatment participated in the trial.

INTERVENTIONS

A central randomisation system allocated participants 1 : 1 to the experimental (methenamine hippurate: 1 g twice daily) or control (once-daily low-dose antibiotics: 50/100 mg of nitrofurantoin, 100 mg of trimethoprim or 250 mg of cefalexin) arm. Crossover between treatment arms was permitted.

MAIN OUTCOME MEASURES

The primary clinical outcome was incidence of symptomatic antibiotic-treated urinary tract infection during the 12-month treatment period. Cost-effectiveness was assessed by incremental cost per quality-adjusted life-year gained, extrapolated over the patient's expected lifetime using a Markov cohort model. Secondary outcomes included post-treatment urinary tract infections, total antibiotic use, microbiologically proven urinary tract infections, antimicrobial resistance, bacteriuria, hospitalisations and treatment satisfaction.

RESULTS

Primary modified intention-to-treat analysis comprised 205 (85%) randomised participants [102/120 (85%) participants in the antibiotics arm and 103/120 (86%) participants in the methenamine hippurate arm] with at least 6 months' data available. During treatment, the incidence rate of symptomatic, antibiotic-treated urinary tract infections decreased substantially in both arms to 1.38 episodes per person-year (95% confidence interval 1.05 to 1.72 episodes per person-year) for methenamine hippurate and 0.89 episodes per person year (95% confidence interval 0.65 to 1.12 episodes per person-year) for antibiotics (absolute difference 0.49; 90% confidence interval 0.15 to 0.84). This absolute difference did not exceed the predefined, strict, non-inferiority limit of one urinary tract infection per person-year. On average, methenamine hippurate was less costly and more effective than antibiotics in terms of quality-adjusted life-years gained; however, this finding was not consistent over the longer term. The urinary tract infection incidence rate 6 months after treatment completion was 1.72 episodes per year in the methenamine hippurate arm and 1.19 in the antibiotics arm. During treatment, 52% of urine samples taken during symptomatic urinary tract infections were microbiologically confirmed and higher proportions of participants taking daily antibiotics (46/64; 72%) demonstrated antibiotic resistance in Escherichia coli cultured from perineal swabs than participants in the methenamine hippurate arm (39/70; 56%) (p-value = 0.05). Urine cultures revealed that during treatment higher proportions of participants and samples from the antibiotic arm grew E. coli resistant to trimethoprim/co-trimoxazole and cephalosporins, respectively. Conversely, post treatment, higher proportions of participants in the methenamine hippurate arm (9/45; 20%) demonstrated multidrug resistance in E. coli isolated from perineal swabs than participants in the antibiotic arm (2/39; 5%) (p = 0.06). All other secondary outcomes and adverse events were similar in both arms.

LIMITATIONS

This trial could not define whether or not one particular antibiotic was more beneficial, and progressive data loss hampered economic evaluation.

CONCLUSIONS

This large, randomised, pragmatic trial in a routine NHS setting has clearly shown that methenamine hippurate is not inferior to current standard care (daily low-dose antibiotics) in preventing recurrent urinary tract infections in women. The results suggest that antimicrobial resistance is proportionally higher in women taking prophylactic antibiotics.

RECOMMENDATIONS FOR RESEARCH

Future research should include evaluation of other non-antibiotic preventative treatments in well-defined homogeneous patient groups, preferably with the comparator of daily antibiotics.

TRIAL REGISTRATION

This trial is registered as ISRCTN70219762 and EudraCT 2015-003487-36.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 23. See the NIHR Journals Library website for further project information.

Multidrug-resistant Uro-associated Escherichia coli Populations and Recurrent Urinary Tract Infections in Patients Performing Clean Intermittent Self-catheterisation

BACKGROUND

The AnTIC trial linked continuous low-dose antibiotic prophylaxis treatments to a lower incidence of symptomatic urinary tract infections (UTIs) among individuals performing clean intermittent self-catheterisation (CISC).

OBJECTIVE

To explore potential mechanisms underlying the protective effects of low-dose antibiotic prophylaxis treatments, blood and urine samples and uro-associated Escherichia coli isolates from AnTIC participants were analysed.

DESIGN SETTING AND PARTICIPANTS

Blood samples (n = 204) were analysed for TLR gene polymorphisms associated with UTI susceptibility and multiple urine samples (n = 558) were analysed for host urogenital responses. E.coli sequence data for 45 temporal isolates recovered from the urine samples of 16 trial participants in the prophylaxis (n = 9) and no-prophylaxis (n = 7) study arms, and characterised by multidrug resistance (MDR), were used to classify individual strains.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

TLR polymorphism data were analysed using Poisson regression. Concentrations of urine host defence markers were analysed using linear mixed-effects models, which accounted for repeated urine samples.

RESULTS AND LIMITATIONS

Urine samples from CISC users, irrespective of antibiotic treatment regimens, were associated with robust urothelial innate responses. No links were identified between TLR genotype and CISC user susceptibility to recurrent UTIs. Microbiological study data were limited to the predominant MDR E. coli population; participants prescribed low-dose prophylactic antibiotics were predominantly colonised by a single uro-associated E. coli strain, while participants given acute antibiotic treatments were each colonised by more than one E. coli strain.

CONCLUSIONS

Antibiotic treatments did not impact urogenital responses to infection in CISC users. Host genetics in terms of TLR polymorphisms played no role in determining CISC user susceptibility to or protection from recurrent UTIs. Prophylactic antibiotic treatments associated with MDR E. coli were associated with colonisation by stable uro-associated E. coli genotypes.

PATIENT SUMMARY

Our findings show that the natural urogenital defences of clean intermittent self-catheterisation (CISC) users were not impacted by antibiotic treatments. For some CISC users, prophylaxis with low-dose antibiotics selected for a stable, predominantly, Esherichia coli rich uromicrobiota.

Dissecting and Evaluating the Therapeutic Targets of Coptis Chinensis Franch in the Treatment of Urinary Tract Infections Induced by Escherichia coli

Coptis chinensis Franch (CCF) is extensively used in the treatment of inflammatory-related diseases. Accumulating studies have previously demonstrated the anti-inflammatory properties of CCF, yet data on its exact targets against urinary tract infections (UTIs) remain largely unknown. Therefore, the present study decodes the potential targets of action of CCF against UTIs by network pharmacology combined with experiment evaluations. Based on the pharmacology network analysis, the current study yielded six core ingredients: quercetin, palmatine (R)-canadine, berlambine, berberine, and berberrubine. The protein–protein interaction network (PPI) was generated by the string database, and then, four targets (IL6, FOS, MYC, and EGFR) were perceived as the major CCF targets using the CytoNCA plug-in. The results of molecular docking showed that the six core constituents of CCF had strong binding affinities toward the four key targets of UTIs after docking into the crystal structure. The enrichment analysis indicated that the possible regulatory mechanisms of CCF against UTIs were based on the modules of inflammation, immune responses, and apoptosis among others. Experimentally, the Escherichia coli (E. coli) strain CFT073 was applied to establish in vivo and in vitro models. In vivo results revealed that the key targets, IL6 and FOS, are significantly upregulated in rat bladder tissues of UTIs, whereas the expression of MYC and EGFR remained steady. Last, in vitro results further confirmed the therapeutic potential of CCF by reducing the expression of IL6 and FOS. In conclusion, IL6 and FOS were generally upregulated in the progression of E. coli–induced UTIs, whereas the CCF intervention exerted a preventive role in host cells stimulated by E. coli, partially due to inhibiting the expression of IL6 and FOS.

Urinary catheter management: what neurologists need to know

Patients with neurological disorders often have lower urinary tract dysfunction, manifesting as urinary retention or urinary incontinence, and so commonly use catheters. Neurologists should therefore be aware of the different types of catheters and appliances and their risks, benefits and complications. Clean intermittent self-catheterisation is preferable to an indwelling catheter; however, if this is not possible, then a suprapubic indwelling catheter is preferable to a urethral catheter for long-term management. We review the decision-making process when selecting catheters for neurological patients, the evidence base regarding the different options and how neurologists can recognise and address complications. We also discuss alternatives to catheterisation, such as non-invasive containment products and surgical treatments, and the indications for urological referral.

Evolution under low antibiotic concentrations: a risk for the selection of Pseudomonas aeruginosa multidrug-resistant mutants in nature

Antibiotic pollution of non-clinical environments might have a relevant impact on human health if resistant pathogens are selected. However, this potential risk is often overlooked, since drug concentrations in nature are usually below their minimal inhibitory concentrations (MICs). Albeit, antibiotic resistant bacteria can be selected even at sub-MIC concentrations, in a range known as the sub-MIC selective window. Using short-term evolution experiments, we have determined the sub-MIC selective windows of the opportunistic pathogen Pseudomonas aeruginosa for seven antibiotics of clinical relevance, finding the ones of quinolones to be the widest, and the ones of polymyxin B and imipenem, the narrowest. Clinically relevant multidrug-resistant mutants arose within the sub-MIC selective windows of most antibiotics tested, being some of these phenotypes mediated by efflux pumps' activity. The fact that the concentration of antibiotics reported in aquatic ecosystems - colonizable by P. aeruginosa - are, in occasions, higher than the ones that select multidrug-resistant mutants in our assays, has implications for understanding the role of different ecosystems and conditions in the emergence of antibiotic resistance from a One-Health perspective. Further, it reinforces the importance of procuring accurate information on the sub-MIC selective windows for drugs of clinical value in pathogens with environmental niches.

Indications for medical antibiotic prophylaxis and potential targets for antimicrobial stewardship intervention: a narrative review

BACKGROUND

Most of the antimicrobial stewardship (AMS) literature has focused on antimicrobial consumption for the treatment of infections, for the prophylaxis of surgical site infection and for the prevention of endocarditis. The role of AMS for medical antibiotic prophylaxis (AP) has not been adequately addressed.

AIMS

To identify targets for AMS interventions for medical AP in adult patients.

SOURCES

Targeted searches were conducted in PubMed.

CONTENT

The various indications for medical AP and relevant evidence from practice guidelines are outlined. The following were identified as potential targets for AMS interventions: (a) addressing under-utilization of antibiotic-sparing strategies (e.g. for recurrent urinary tract infections, recurrent soft-tissue infections, recurrent exacerbations associated with bronchiectasis or chronic obstructive pulmonary disease), (b) reducing unnecessary AP beyond recommended indications (e.g. for acute pancreatitis, bite wounds, or urinary catheter manipulations), (c) reducing the use of AP with a broader spectrum than necessary, (d) reducing the use of AP for longer than the recommended duration (e.g. AP for prevention of osteomyelitis in open fractures or AP in high-risk neutropenia), (e) evaluating the role of antibiotic cycling to prevent the emergence of resistance during prolonged AP (e.g. in recurrent urinary tract infections or prophylaxis for spontaneous bacterial peritonitis), and (f) addressing research gaps regarding appropriate indications or antibiotic regimens for medical prophylaxis.

IMPLICATIONS

This review summarizes current trends in AP and proposes targets for AMS interventions.

Peripheral Immune Dysfunction: A Problem of Central Importance after Spinal Cord Injury

Simple Summary

Spinal cord injury can result in an increased vulnerability to infections, but until recently the biological mechanisms behind this observation were not well defined. Immunosuppression and concurrent sustained peripheral inflammation after spinal cord injury have been observed in preclinical and clinical studies, now termed spinal cord injury-induced immune depression syndrome. Recent research indicates a key instigator of this immune dysfunction is altered sympathetic input to lymphoid organs, such as the spleen, resulting in a wide array of secondary effects that can, in turn, exacerbate immune pathology. In this review, we discuss what we know about immune dysfunction after spinal cord injury, why it occurs, and how we might treat it.

Abstract

Individuals with spinal cord injuries (SCI) exhibit increased susceptibility to infection, with pneumonia consistently ranking as a leading cause of death. Despite this statistic, chronic inflammation and concurrent immune suppression have only recently begun to be explored mechanistically. Investigators have now identified numerous changes that occur in the peripheral immune system post-SCI, including splenic atrophy, reduced circulating lymphocytes, and impaired lymphocyte function. These effects stem from maladaptive changes in the spinal cord after injury, including plasticity within the spinal sympathetic reflex circuit that results in exaggerated sympathetic output in response to peripheral stimulation below injury level. Such pathological activity is particularly evident after a severe high-level injury above thoracic spinal cord segment 6, greatly increasing the risk of the development of sympathetic hyperreflexia and subsequent disrupted regulation of lymphoid organs. Encouragingly, studies have presented evidence for promising therapies, such as modulation of neuroimmune activity, to improve regulation of peripheral immune function. In this review, we summarize recent publications examining (1) how various immune functions and populations are affected, (2) mechanisms behind SCI-induced immune dysfunction, and (3) potential interventions to improve SCI individuals’ immunological function to strengthen resistance to potentially deadly infections.

New Approaches to Profile the Microbiome for Treatment of Neurodegenerative Disease

Progressive neurodegenerative diseases represent some of the largest growing treatment challenges for public health in modern society. These diseases mainly progress due to aging and are driven by microglial surveillance and activation in response to changes occurring in the aging brain. The lack of efficacious treatment options for Alzheimer's disease (AD), as the focus of this review, and other neurodegenerative disorders has encouraged new approaches to address neuroinflammation for potential treatments. Here we will focus on the increasing evidence that dysbiosis of the gut microbiome is characterized by inflammation that may carry over to the central nervous system and into the brain. Neuroinflammation is the common thread associated with neurodegenerative diseases, but it is yet unknown at what point and how innate immune function turns pathogenic for an individual. This review will address extensive efforts to identify constituents of the gut microbiome and their neuroactive metabolites as a peripheral path to treatment. This approach is still in its infancy in substantive clinical trials and requires thorough human studies to elucidate the metabolic microbiome profile to design appropriate treatment strategies for early stages of neurodegenerative disease. We view that in order to address neurodegenerative mechanisms of the gut, microbiome and metabolite profiles must be determined to pre-screen AD subjects prior to the design of specific, chronic titrations of gut microbiota with low-dose antibiotics. This represents an exciting treatment strategy designed to balance inflammatory microglial involvement in disease progression with an individual's manifestation of AD as influenced by a coercive inflammatory gut.

Diagnosis and Non-Surgical Management of Urinary Incontinence - A Literature Review with Recommendations for Practice

Urinary incontinence (UI) is a bothersome symptom with population studies suggesting a prevalence of 13.1% in women and 5.4% in men. While a significant cohort of patients with this complaint may ultimately require surgical management to achieve complete continence, a number of non-surgical measures exist to improve symptoms and quality of life. A range of guidelines exist on this topic, including those published by the European Association of Urology (EAU), the International Continence Society (ICS), the American Urological Association (AUA) and the UK's National Institute for Health and Care Excellence (NICE). The aim of our study is to provide an overview of the initial assessment of patients with UI including history taking, examination and basic investigations. Our review outlines non-surgical management strategies for UI, including conservative measures, behavioral and physical therapies and drug treatment. We shall also examine the above guidelines and present a narrative overview of the literature surrounding the diagnosis and non-surgical management of urinary incontinence.

The Benefits and Harms of Antibiotic Prophylaxis for Urinary Tract Infection in Older Adults

BACKGROUND

The role of antibiotics in preventing urinary tract infection (UTI) in older adults is unknown. We sought to quantify the benefits and risks of antibiotic prophylaxis among older adults.

METHODS

We conducted a matched cohort study comparing older adults (≥66 years) receiving antibiotic prophylaxis, defined as antibiotic treatment for ≥30 days starting within 30 days of a positive culture, with patients with positive urine cultures who received antibiotic treatment but did not receive prophylaxis. We matched each prophylaxis recipient to 10 nonrecipients based on organism, number of positive cultures, and propensity score. Outcomes included (1) emergency department (ED) visit or hospitalization for UTI, sepsis, or bloodstream infection within 1 year; (2) acquisition of antibiotic resistance in urinary tract pathogens; and (3) antibiotic-related complications.

RESULTS

Overall, 4.7% (151/3190) of UTI prophylaxis patients and 3.6% (n = 1092/30 542) of controls required an ED visit or hospitalization for UTI, sepsis, or bloodstream infection (hazard ratio [HR], 1.33; 95% confidence interval [CI], 1.12-1.57). Acquisition of antibiotic resistance to any urinary antibiotic (HR, 1.31; 95% CI, 1.18-1.44) and to the specific prophylaxis agent (HR, 2.01; 95% CI, 1.80-2.24) was higher in patients receiving prophylaxis. While the overall risk of antibiotic-related complications was similar between groups (HR, 1.08; 95% CI, .94-1.22), the risk of Clostridioidesdifficile and general medication adverse events was higher in prophylaxis recipients (HR [95% CI], 1.56 [1.05-2.23] and 1.62 [1.11-2.29], respectively).

CONCLUSIONS

Among older adults with UTI, the harms of long-term antibiotic prophylaxis may outweigh their benefits.

A Novel Device-Integrated Drug Delivery System for Local Inhibition of Urinary Tract Infection

Background: Catheter-associated urinary tract infection (CAUTI) is a frequent community-acquired infection and the most common nosocomial infection. Here, we developed a novel antimicrobial catheter concept that utilizes a silicone-based interpenetrating polymer network (IPN) as balloon material to facilitate a topical slow-release prophylaxis of antibacterial agents across the balloon to the urinary bladder.

Methods: The balloon material was achieved by modifying low shore hardness silicone tubes with a hydrogel interpenetrating polymer in supercritical CO₂ using the sequential method. Release properties and antibacterial efficacy of the IPN balloon treatment concept was investigated in vitro and in a porcine CAUTI model developed for the study. In the latter, Bactiguard Infection Protection (BIP) Foley catheters were also assessed to enable benchmark with the traditional antimicrobial coating principle.

Results: Uropathogenic Escherichia coli was undetectable in urinary bladders and on retrieved catheters in the IPN treatment group as compared to control that revealed significant bacteriuria (>10⁵ colony forming units/ml) as well as catheter-associated biofilm. The BIP catheters failed to prevent E. coli colonization of the bladder but significantly reduced catheter biofilm formation compared to the control.

Conclusion: The IPN-catheter concept provides a novel, promising delivery route for local treatment in the urinary tract.

Nitrofurantoin 100 mg versus 50 mg prophylaxis for urinary tract infections, a cohort study

OBJECTIVES

Guidelines do not distinguish between 50 mg or 100 mg nitrofurantoin as daily prophylaxis for recurrent urinary tract infection (UTI), although 50 mg might have a better safety profile. Our objective was to compare the effectiveness and safety of both regimens.

METHODS

Data were retrospectively collected from 84 Dutch GP practices between 2013 and 2020. Nitrofurantoin prescriptions of 100 mg and 50 mg every 24 hours in women were included. Cox proportional hazard regression analysis was used to calculate hazard ratios on first episode of UTI, pyelonephritis and (adverse) events. Patients were followed for the duration of consecutive repeated prescriptions, assuming non-informative right censoring, up to 1 year.

RESULTS

Nitrofurantoin prophylaxis was prescribed in 1893 patients. Median lengths of follow up were 90 days (interquartile range (IQR) 37-179 days) for 100 mg (n = 551) and 90 days (IQR 30-146 days) for 50 mg (n = 1342) with few differences in baseline characteristics between populations. Under 100 mg and 50 mg, 82/551 (14.9%) and 199/1342 (14.8%) developed UTI and 46/551 (8.3%) and 81/1342 (6.0%) developed pyelonephritis, respectively. Adjusted HRs of 100 mg versus 50 mg were 1.01 (95% CI 0.78-1.30) on first UTI, 1.37 (95% CI 0.95-1.98) on first pyelonephritis episode, 1.82 (95% CI 1.20-2.74) on first consultation for cough, 2.68 for dyspnoea (95% CI 1.11-6.45) and 2.43 for nausea (95% CI 1.03-5.74).

CONCLUSION

Daily prophylaxis for recurrent UTI with 100 mg instead of 50 mg nitrofurantoin was associated with an equivalent hazard on UTI or pyelonephritis, and a higher hazard on cough, dyspnoea and nausea. We recommend 50 mg nitrofurantoin as daily prophylaxis.

Weekly Sequential Antibioprophylaxis for Recurrent Urinary Tract Infections Among Patients With Neurogenic Bladder: A Randomized Controlled Trial

BACKGROUND

Recurrent urinary tract infections (R-UTIs) are the main cause of morbidity and hospitalizations in subjects with neurogenic bladder (NB) due to spinal cord injury (SCI). We evaluated the efficacy of weekly oral cyclic antibiotic (WOCA) prophylaxis (ie, the alternate weekly administration of 2 antibiotics) in preventing R-UTIs.

METHODS

Randomized (1:1), open-label, superiority-controlled trial compared WOCA prophylaxis to no prophylaxis (control) for 6 months in patients with NB due to SCI, using clean intermittent self-catheterization, and suffering from R-UTIs. Primary outcome was incidence of symptomatic antibiotic-treated UTIs. Secondary outcomes were number of febrile UTIs, number of hospitalizations, WOCA tolerance, antibiotic consumption, number of negative urine cultures, and emergence of bacterial resistance in urinary, intestinal, and nasal microbiota.

RESULTS

Forty-five patients were either allocated to the WOCA group (n = 23) or the control group (n = 22). Median (IQR) incidence of symptomatic antibiotic-treated UTIs was 1.0 (0.5-2.5) in the WOCA group versus 2.5 (1.2-4.0) (P = .0241) in the control group. No febrile UTIs were recorded in the WOCA group versus 9 (45.0%) (P < .001) in the control group. The median number of additional antibiotic treatment was 0.0 (IQR, 0.0-2.0) versus 3.0 (2.0-5.0) (P = .004) in the WOCA and control groups, respectively. Only few adverse events were reported. No impact on emergence of bacterial resistance was observed.

CONCLUSIONS

WOCA is efficient and well tolerated in preventing R-UTIs in SCI patients. In our study, we did not observe any emergence of antibiotic resistance in digestive and nasal microbiological cultures.

CLINICAL TRIALS REGISTRATION

NCT01388413.

Treatment of neurogenic lower urinary tract symptoms: main contributions from 2018 and 2019

PURPOSE OF REVIEW

This review aims to update the studies involving the treatment of lower urinary tract symptoms (LUTS) in neurogenic patients, published in the last two years.

RECENT FINDINGS

Treatment of neurogenic LUTS (NLUTS) patients with β3 adrenoreceptor agonists was investigated in real-life conditions. A randomized controlled trial compared the efficacy of antimuscarinics versus onabotulinum toxin A in neurogenic patients. The use of desmopressin to treat nocturia in multiple sclerosis patients is also reported. The long-term treatment with BontA efficacy, its discontinuation, and possible strategies to maintain patients on treatment were also evaluated. Sacral neuromodulation and tibial nerve stimulation are continuously being evaluated in neurogenic patients, especially in the last years.

SUMMARY

The management of urinary tract infections and vesical lithiasis, two common complications in NLUTS patients, and the management of both these patients was assessed in clinical trials.A trial evaluating the use of the anti-Nogo-A antibody after a spinal cord injury to facilitate neuronal rewiring and prevent or improve NLUTS was reported for the first time.

Urinary tract infections and multiple sclerosis: Recommendations from the French Multiple Sclerosis Society

OBJECTIVES

Establish recommendations for the management of UTIs in MS patients.

BACKGROUND

Urinary tract infections (UTIs) are common during multiple sclerosis (MS) and are one of the most common comorbidities potentially responsible for deaths from urinary sepsis.

METHODS

The recommendations attempt to answer three main questions about UTIs and MS. The French Group for Recommendations in MS (France4MS) did a systematic review of articles from PubMed and universities databases (01/1980-12/2019). The RAND/UCLA appropriateness method, which has been developed to synthesize the scientific literature and expert opinions on health care topics, was used for reaching a formal agreement. 26 MS experts worked on the full-text review and a group of 70 multidisciplinary health care specialists validated the final evaluation of summarized evidences.

RESULTS

UTIs are not associated with an increased risk of relapse and permanent worsening of disability. Only febrile UTIs worsen transient disability through the Uhthoff phenomenon. Some immunosuppressive treatments increase the risk of UTIs in MS patients and require special attention especially in case of hypogammaglobulinemia. Experts recommend to treat UTIs in patients with MS, according to recommendations of the general population. Prevention of recurrent UTIs requires stabilization of the neurogenic bladder. In some cases, weekly oral cycling antibiotics can be proposed after specialist advice. Asymptomatic bacteriuria should not be screened for or treated systematically except in special cases (pregnancy and invasive urological procedures).

CONCLUSION

Physicians and patients should be aware of the updated recommendations for UTis and MS.

Current Evidence Related to Intermittent Catheterization: A Scoping Review

PURPOSE

The purpose was to summarize evidence related to adherence to intermittent catheterization (IC), complication rates, satisfaction with IC, and its effect on health-related quality of life.

PROBLEM

Intermittent catheterization is frequently used to manage lower urinary tract dysfunctions including urinary retention and urinary incontinence, but research suggests that care for patients using IC may not always be based on evidence.

METHODS

Scoping review.

SEARCH STRATEGY

We searched the PubMed, EMBASE, CINAHL databases, and the Cochrane Database for Systematic Reviews to identify studies published between January 2009 and March 2019. Seventy studies met inclusion criteria and were evaluated for adherence, complication rates, satisfaction, and health-related quality in adults and children using IC for bladder management.

FINDINGS

Recent research was variable in both quantity and quality. The evidence suggests that (1) most patients can successfully master IC and that functional status is likely the most important predictor of success; (2) adherence to IC probably decreases over time; (3) urinary tract infections (UTIs) are the most common complication of IC and that prophylactic antibiotic therapy may reduce the risk of recurrent UTIs; (4) urinary incontinence is also a common complication; and (5) other complications such as urethral strictures, bladder stones, hematuria, and urethral false passage do occur but are less prevalent than UTIs and incontinence between catheterizations. Our review also revealed multiple gaps in the evidence to support care for patients using IC.

CONCLUSIONS

Research priorities include a need for prospective studies of the epidemiology and risk factors for IC-related complications, along with intervention studies to determine how to improve outcomes for patients using IC to manage bladder function.

Characterizing infection in anti-neutrophil cytoplasmic antibody-associated vasculitis: results from a longitudinal, matched-cohort data linkage study

OBJECTIVES

Infection exerts a major burden in ANCA-associated vasculitis (AAV), however, its precise extent and nature remains unclear. In this national study we aimed to longitudinally quantify, characterize and contextualize infection risk in AAV.

METHODS

We conducted a multicentre matched cohort study of AAV. Complementary data on infections were retrieved via data linkage with the population-based Scottish microbiological laboratory, hospitalization and primary care prescribing registries.

RESULTS

A total of 379 AAV patients and 1859 controls were followed up for a median of 3.5 years (interquartile range 1.9-5.7). During follow-up, the proportions of AAV patients with at least one laboratory-confirmed infection, severe infection and primary care antibiotic prescription were 55.4%, 35.6% and 74.6%, respectively. The risk of infection was higher in AAV than in matched controls {laboratory-confirmed infections: incidence rate ratio [IRR] 7.3 [95% confidence interval (CI) 5.6, 9.6]; severe infections: IRR 4.4 [95% CI 3.3, 5.7]; antibiotic prescriptions: IRR 2.2 [95% CI 1.9, 2.6]}. Temporal trend analysis showed that AAV patients remained at a higher risk of infections throughout the follow-up period, especially year 1. Although the Escherichia genus was the most commonly identified pathogen (16.6% of AAV, 5.5% of controls; P < 0.0001), AAV patients had the highest risk for Herpes [IRR 12.5 (95% CI 3.7, 42.6)] and Candida [IRR 11.4 (95% CI 2.4, 55.4)].

CONCLUSION

AAV patients have up to seven times higher risk of infection than the general population and the overall risk remains significant after 8 years of follow-up. The testing of enhanced short- to medium-term prophylactic antibiotic regimes should be considered.