Efficacy of antimicrobial intravesical treatment for uncomplicated recurrent urinary tract infections: a systematic review

Is Intravesical Gentamicin the New Gold Standard to Manage Refractory Urinary Tract Infections?-Experience From a Dedicated Multidisciplinary Complex UTI Clinic

AIMS

To assess the effectiveness of intravesical gentamicin in managing recurrent urinary tract infections (rUTIs) refractory to first- and second-line treatments.

METHODS AND MATERIALS

This single-centre prospective cohort study included 41 patients treated with intravesical gentamicin over a 24-month period from 2021 to 2023. A multidisciplinary team comprising functional urologists, microbiologists, and specialist nurses was involved in the decision-making process and in designing the treatment protocol. Patients self-administered gentamicin instillations into the bladder according to a 6-month instillation schedule. Patients were followed up during and after the treatment period to assess the treatment response.

RESULTS

A total of 41 patients with rUTIs were treated using the 6-month intravesical gentamicin regimen. Of these, 10 were male and 31 were female, with a mean age of 53 years. E. coli was isolated from urine cultures in 19 patients (46%), while 19 patients had multiple organisms. Serum gentamicin levels were undetectable in all patients 1 week after treatment initiation. The mean follow-up period was 15 months with minimum follow up of 6 months for all patients. Following gentamicin administration, hospital admission rates due to urosepsis decreased from 46% to 5%, and the prevalence of multidrug-resistant organisms in urine cultures decreased from 44% to 10%. A significant reduction in UTI frequency was observed in 80.5% of patients, with 71% reporting good to excellent Patient Global Impression of Improvement (PGI-I) scores. Additionally, 76% of patients reported a significant improvement in Quality of Life (QoL).

CONCLUSION

In our cohort of patients with recurrent and refractory UTIs, intravesical gentamicin instillations has shown to be both safe and effective, leading to notable improvements in patients' symptoms and QoL.

Can We Prevent Recurrent UTIs Without Antibiotics, in Both Those Who Do and Do Not Use Catheters? ICI-RS 2024

AIMS

Urinary tract infections are one of the most common reasons for antibiotic prescription. The widespread use of antibiotic treatments contributes to the global health problem of antimicrobial resistance development. To slow down the progression of antimicrobial resistance, it is essential that we explore nonantibiotic preventive treatments for this common condition. We aim to report discussions regarding nonantibiotic preventive strategies for recurrent urinary tract infections in both catheterized and non-catheterized patients that took place at the International Consultation on Incontinence-Research Society meeting in Bristol in 2024.

METHODS

We undertook a think-tank session during this multidisciplinary meeting specifically designated for discussion regarding both established and emerging nonantibiotic treatments for UTI prevention in both catheterized and non-catheterized patients. This led to the generation of pertinent research questions, which hope to shape future UTI research.

RESULTS

We describe the discussions that took place and document the important research questions that were proposed during the International Consultation on Incontinence-Research Society meeting in Bristol in 2024.

CONCLUSIONS

There is a range of established UTI preventative strategies for UTI prevention in both catheterized and non-catheterized patients. Emerging UTI prevention treatments have varying levels of evidence to support their use, and in many areas, further research is needed to establish their place in clinical pathways.

Overcoming challenges in the management of recurrent urinary tract infections

INTRODUCTION

Urinary tract infection (UTI) is a major global health concern. While acute UTIs can usually be effectively treated, recurrent UTIs (rUTIs) impact patients for years, causing significant morbidity and can become refractory to front-line antibiotics.

AREAS COVERED

This review discusses the risk factors associated with rUTI, current rUTI treatment paradigms, prophylactic strategies, and challenges in rUTI diagnostics. We specifically discuss common risk factors for rUTI, including biological sex, age, menopause status, and diabetes mellitus. We also review recently available evidence for commonly used treatments, from oral antibiotic therapy to intravesical antimicrobials, electrofulguration of chronic cystitis, and the last-resort treatment, cystectomy. We discuss the most current literature evaluating prophylactic strategies for rUTI including long-term antibiotic prophylaxis, estrogen hormone therapy, and dietary supplements. Finally, we address the important role of UTI diagnostics in effective rUTI management and review the strengths and limitations of both current and emerging UTI diagnostic platforms as well as their ability to operate at point-of-care.

EXPERT OPINION

We discuss the current challenges faced by clinicians in managing rUTI in women and the steps that should be taken so that clinicians, scientists, and patients can work together to better understand the disease and develop better strategies for its management.

Current and emerging strategies to curb antibiotic-resistant urinary tract infections

Rising rates of antibiotic resistance in uropathogenic bacteria compromise patient outcomes and prolong hospital stays. Consequently, new strategies are needed to prevent and control the spread of antibiotic resistance in uropathogenic bacteria. Over the past two decades, sizeable clinical efforts and research advances have changed urinary tract infection (UTI) treatment and prevention strategies to conserve antibiotic use. The emergence of antimicrobial stewardship, policies from national societies, and the development of new antimicrobials have shaped modern UTI practices. Future UTI management practices could be driven by the evolution of antimicrobial stewardship, improved and readily available diagnostics, and an improved understanding of how the microbiome affects UTI. Forthcoming UTI treatment and prevention strategies could employ novel bactericidal compounds, combinations of new and classic antimicrobials that enhance bacterial killing, medications that prevent bacterial attachment to uroepithelial cells, repurposing drugs, and vaccines to curtail the rising rates of antibiotic resistance in uropathogenic bacteria and improve outcomes in people with UTI.

Gaps in knowledge and recurrent urinary tract infections in women

PURPOSE OF REVIEW

The focus of this review is to present recent literature and gaps in knowledge (GIKs) surrounding the current and future treatment and prevention of uncomplicated recurrent urinary tract infections (rUTIs) in women.

RECENT FINDINGS

Recurrent urinary tract infections are common, significantly reduce quality of life, and create a substantial economic burden to the healthcare system. They are disproportionately affecting the postmenopausal women. Antibiotics, which are used for the treatment and prophylaxis of uncomplicated rUTI, have become problematic, as there is a global rise in allergy and resistance to these agents and their use is associated with further antimicrobial resistance. Thus, in recent decades, several alternative, nonantibiotic approaches have been evaluated.

SUMMARY

There is a critical need for a concerted and standardized methodology for diagnosing, treating, and monitoring women with rUTIs. Additionally, novel nonantibiotic alternative treatment and preventive measures for UTIs are desperately required to address the global issue of antibiotic recalcitrance in all age groups, and specifically older women. Research efforts have sought to develop alternative and more effective techniques; many of which appear to be promising, but require additional evaluation and validation through clinical trials.

Can we define the optimal postvoid residual volume at which intermittent catheterization should be recommended, and are there other measures that could guide an intermittent catheterization protocol: ICI-RS 2023

AIMS

The postvoid residual (PVR) volume of urine in the bladder is widely used in clinical practice as a guide to initiate treatment, including clean-intermittent self-catheterization (CISC). It is often believed that an elevated PVR causes complications such as recurrent urinary tract infections (UTI) and renal failure. However, evidence for this is limited and identifying alternative measures to guide treatment decisions may optimize patient care. At the International Consultation on Incontinence Research Society (ICI-RS) meeting in 2023 a Think Tank addressed the question of whether we can define the optimal PVR at which CISC should be recommended, and whether there are other measures that could guide a CISC protocol.

METHODS

The Think Tank conducted a literature review and expert consensus meeting focusing on current limitations in defining and measuring PVR, and highlighting other measures that may optimize selection for, and persistence with, CISC.

RESULTS

There is no consensus on the threshold value of PVR that is considered "elevated" or "significant." There is a lack of standardization on terminology, and the normal range of PVR in different populations of different ages remains to be well-studied. The measurement of PVR is influenced by several factors, including intraindividual variation, timing and method of measurement. Furthermore, the evidence linking an elevated PVR with complications such as UTI and renal failure is mixed. Other measures, such as bladder voiding efficiency or urodynamic parameters, may be better at predicting such complications, and therefore may be more relevant at guiding a CISC protocol.

CONCLUSIONS

There is a lack of high quality evidence to support PVR as a predictor for complications of UTI or renal failure. Threshold values for normal PVR in different populations are unknow, and so threshold values for "elevated" or "significant" PVR cannot be determined. Other factors, such as urodynamic findings, may be better at predicting complications and therefore guiding management decisions, and this remains to be studied. Areas for further research are proposed.

VesiX cetylpyridinium chloride is rapidly bactericidal and reduces uropathogenic Escherichia coli bladder epithelial cell invasion in vitro

Management of urinary tract infection (UTI) in postmenopausal women can be challenging. The recent rise in resistance to most of the available oral antibiotic options together with high recurrence rate in postmenopausal women has further complicated treatment of UTI. As such, intravesical instillations of antibiotics like gentamicin are being investigated as an alternative to oral antibiotic therapies. This study evaluates the efficacy of the candidate intravesical therapeutic VesiX, a solution containing the cationic detergent Cetylpyridinium chloride, against a broad range of uropathogenic bacterial species clinically isolated from postmenopausal women with recurrent UTI (rUTI). We also evaluate the cytotoxicity of VesiX against cultured bladder epithelial cells and find that low concentrations of 0.0063% and 0.0125% provide significant bactericidal effect toward diverse bacterial species including uropathogenic Escherichia coli (UPEC), Klebsiella pneumoniae, Enterococcus faecalis, Pseudomonas aeruginosa, and Proteus mirabilis while minimizing cytotoxic effects against cultured 5637 bladder epithelial cells. Lastly, to begin to evaluate the potential utility of using VesiX in combination therapy with existing intravesical therapies for rUTI, we investigate the combined effects of VesiX and the intravesical antibiotic gentamicin. We find that VesiX and gentamicin are not antagonistic and are able to reduce levels of intracellular UPEC in cultured bladder epithelial cells.

IMPORTANCE

When urinary tract infections (UTIs), which affect over 50% of women, become resistant to available antibiotic therapies dangerous complications like kidney infection and lethal sepsis can occur. New therapeutic paradigms are needed to expand our arsenal against these difficult to manage infections. Our study investigates VesiX, a Cetylpyridinium chloride (CPC)-based therapeutic, as a candidate broad-spectrum antimicrobial agent for use in bladder instillation therapy for antibiotic-resistant UTI. CPC is a cationic surfactant that is FDA-approved for use in mouthwashes and is used as a food additive but has not been extensively evaluated as a UTI therapeutic. Our study is the first to investigate its rapid bactericidal kinetics against diverse uropathogenic bacterial species isolated from postmenopausal women with recurrent UTI and host cytotoxicity. We also report that together with the FDA-approved bladder-instillation agent gentamicin, VesiX was able to significantly reduce intracellular populations of uropathogenic bacteria in cultured bladder epithelial cells.

The management of recurrent urinary tract infections within a nurse-led urology team

The aim of this article is to share experience and learning of managing recurrent urinary tract infections (UTIs) within a specialist urology nurse-led team based at a district general hospital. It looks at current practice and supporting evidence for how to manage and treat recurrent UTIs in both male and female patients. Two case studies are presented to illustrate the management strategies and outcomes, demonstrating a planned approach that informs the design of a local management guideline to organise patients' care.

Urinary Glycosaminoglycans Are Associated with Recurrent UTI and Urobiome Ecology in Postmenopausal Women

Glycosaminoglycans (GAGs) are linear, negatively charged polysaccharides composed of repeating disaccharide units of uronic acid and amino sugars. The luminal surface of the bladder epithelium is coated with a GAG layer. These urothelial GAGs are thought to provide a protective barrier and serve as a potential interaction site with the urinary microbiome (urobiome). Previous studies have profiled urinary GAG composition in mixed cohorts, but the urinary GAG composition in postmenopausal women remains undefined. To investigate the relationship between GAGs and recurrent urinary tract infection (rUTI), we profiled urinary GAGs in a controlled cohort of postmenopausal women. We found that chondroitin sulfate (CS) is the major urinary GAG in postmenopausal women and that urinary CS was elevated in women with active rUTI. We also associated urinary GAGs with urobiome composition and identified bacterial species that significantly associated with urinary GAG concentration. Corynebacterium amycolatum, Porphyromonas somerae, and Staphylococcus pasteuri were positively associated with heparin sulfate or hyaluronic acid, and bacterial species associated with vaginal dysbiosis were negatively correlated with urinary CS. Altogether, this work defines changes in urinary GAG composition associated with rUTI and identifies new associations between urinary GAGs and the urobiome that may play a role in rUTI pathobiology.

Effective Treatments of UTI—Is Intravesical Therapy the Future?

Urinary tract infection (UTI) afflicts millions of patients globally each year. While the majority of UTIs are successfully treated with orally administered antibiotics, the impact of oral antibiotics on the host microbiota is under close research scrutiny and the potential for dysbiosis is a cause for concern. Optimal treatment of UTI relies upon the selection of an agent which displays appropriate pharmacokinetic-pharmacodynamic (PK-PD) properties that will deliver appropriately high concentrations in the urinary tract after oral administration. Alternatively, high local concentrations of antibiotic at the urothelial surface can be achieved by direct instillation into the urinary tract. For antibiotics with the appropriate physicochemical properties, this can be of critical importance in cases for which an intracellular urothelial bacterial reservoir is suspected. In this review, we summarise the underpinning biopharmaceutical barriers to effective treatment of UTI and provide an overview of the evidence for the deployment of the intravesical administration route for antibiotics.

Urinary Glycosaminoglycans are Associated with Recurrent UTI and Urobiome Ecology in Postmenopausal Women

Glycosaminoglycans (GAGs) are linear, negatively charged polysaccharides composed of repeating disaccharide units of uronic acid and amino sugars. The luminal surface of the bladder epithelium is coated with a GAG layer. These urothelial GAGs are thought to provide a protective barrier and serve as a potential interaction site with the urinary microbiome (urobiome). Previous studies have profiled urinary GAG composition in mixed cohorts, but the urinary GAG composition in postmenopausal women remains undefined. To investigate the relationship between GAGs and recurrent UTI (rUTI), we profiled urinary GAGs in a controlled cohort of postmenopausal women. We found that chondroitin sulfate (CS) is the major urinary GAG in postmenopausal women and that urinary CS was elevated in women with active rUTI. We also associated urinary GAGs with urobiome composition and identified bacterial species that significantly associated with urinary GAG concentration. Corynebacterium amycolatum, Porphyromonas somerae , and Staphylococcus pasteuri were positively associated with heparin sulfate or hyaluronic acid and bacterial species associated with vaginal dysbiosis were negatively correlated to urinary CS. Altogether, this work defines changes in urinary GAG composition associated with rUTI and identifies new associations between urinary GAGs and the urobiome that may play a role in rUTI pathobiology.

Intraoperative Gentamicin Intravesical Instillation for Prevention of Urinary Tract Infection After Urogynecologic Surgery: A Randomized Controlled Trial

IMPORTANCE

Currently available evidence for efficacy of postoperative antibiotics to prevent postoperative urinary tract infection (UTI) conflicts. Oral antibiotics rely on patient adherence and can cause unwanted systemic effects. Gentamicin is a broad-spectrum antibiotic with rapid bactericidal activity and, when administered intravesically, has no systemic absorption through intact urothelium.

OBJECTIVE

We aimed to determine whether a single intravesical instillation of gentamicin at the conclusion of urogynecologic surgery would reduce the proportion of women treated for UTI within 6 weeks postoperatively compared with sham instillation.

STUDY DESIGN

This was a multicenter, randomized (stratified by study site, route of prolapse repair ±suburethral sling, with balanced 1:1 randomization), participant-masked, sham-controlled, study. The primary outcome was the proportion of participants treated with antibiotics for UTI within 6 weeks postoperatively. An adjusted multivariable logistic regression model was constructed to determine predictors of postoperative UTI treatment.

RESULTS

Three hundred seventy participants were randomized (gentamicin, 185; sham, 185), and data from 363 participants were analyzed (gentamicin, 183; sham, 180). Nineteen women in the gentamicin group and 20 women in the sham group were treated for UTI within 6 weeks postoperatively (10.4% vs 11.1%, P = 0.87). There were no adverse events related to the instillations. Increasing age (odds ratio, 1.028 [1.000-1.057]) and number of intraoperative transurethral instrumentations (odds ratio, 1.342 [1.080-1.668]) were independent predictors of postoperative UTI treatment.

CONCLUSIONS

In women undergoing urogynecologic surgery, postoperative intravesical gentamicin did not reduce the incidence of postoperative UTI. The number of intraoperative transurethral instrumentations is an important, potentially modifiable risk factor for postoperative UTI treatment.

Intravesical Gentamicin: An Option for Therapy and Prophylaxis against Recurrent UTIs and Resistant Bacteria in Neurogenic Bladder Patients on Intermittent Catheterization

This is a retrospective study of our experience with Gentamicin intravesical instillation as therapy and prophylaxis in patients with lower urinary tract infections (UTIs) undergoing clean intermittent catheterization because of a neurogenic bladder. It is an alternative therapy when all other systemic treatments have failed as it is still an off-label prescription.