Antibiotic Coating of the Artificial Urinary Sphincter (AMS 800): Is it Worthwhile?

Management of Infections Associated with Penile Prostheses and Artificial Urinary Sphincters

Prosthetic urology can substantially enhance the quality of life for patients. However, it is not without challenges. Infections of penile prostheses and artificial urinary sphincters are often difficult to diagnose, manage, and treat. Over time, device improvements, refined surgical methods, better understanding of microbiology, and biofilms in combination with higher sterility standards and protocols, have significantly reduced the rates of infection. Here, the authors offer a comprehensive overview of prosthetic urologic infections and their management in the current era.

Indwelling Urological Device Biofilm Composition and Characteristics in the Presence and Absence of Infection

OBJECTIVE

To characterize microbial biofilms associated with different device types used in the urological field including ureteral stents, sacral neuromodulation (SNM) devices, penile prostheses, and artificial urinary sphincters (AUS).

MATERIALS AND METHODS

Data from 4 studies, each reporting biofilm composition of a particular device type, were pooled and included for inter-device analysis. Studies recruited adults scheduled for ureteral stent, SNM, IPP, or AUS removal/revision. Device (n = 115) biofilms and controls were analyzed with multi-omics approaches, and compositions were compared across device types and clinical factors.

RESULTS

Microbiota present on each device type was distinct from that of perineal, rectal, or urine flora (P <.01). Biofilm microbial counts (P <.001) and diversity (P = .024) differed by device type. Ureteral stents had greater microbial counts than other device types (P <.001). Staphylococcus, Pseudomonas, Lactobacillus, Ureaplasma were commonly detected across devices. Device biofilms harbored a greater proportion of Proteobacteria phylum, and the rectal, perineal, and urine flora harbored a greater proportion of Firmicutes. Unique microbe-metabolite interaction networks were identified in presence and absence of infection. Antibiotic-resistance genes including sul2 (sulfonamide resistance) and rpoB (rifampin resistance) were detected in biofilms across device types. Biofilm reconstitution in vitro differed by device type from which strains were isolated.

CONCLUSION

Ureteral stents, sacral neuromodulation devices, penile prostheses, and artificial urinary sphincters harbored unique microbial and metabolite profiles that differed from those of skin, urine, and rectal flora. The findings of this study set the groundwork for investigation of novel strategies to reduce device-associated infection risk within and outside urology.

Artificial urinary sphincter: recent developments and the way forward

PURPOSE OF REVIEW

The AMS 800 has dominated the treatment of postprostatectomy urinary incontinence (PPUI) due to intrinsic sphincter deficiency (ISD) for five decades. A narrative review from June 2022 to June 2024 was conducted using 'artificial urinary sphincter' (AUS) MeSH terms in Embase. We extracted information on innovative AUS, randomized controlled trials (RCTs) or prospective studies, and systematic reviews. We evaluated the latest guidelines and consensus and analyzed current trends to discuss options for advancing AUS practices.

RECENT FINDINGS

Of 465 papers identified, 320 were excluded (irrelevant, duplicates, non-AUS devices, non-English, veterinary), and 145 were reviewed, with 24 selected: seven on novel AUS in development, 7 with higher-level evidence (1 RCT, 1 prospective, 4 systematic reviews, 1 nonsystematic review), and 9 retrospective relevant studies [pressure regulating balloon (PRB), revision strategies, radiotherapy history, manual dexterity/cognition, transscrotal vs. transperineal approach]. The final paper summarized current guidelines from Asia & Pacific on AUS.

SUMMARY

In the past 2 years, six novel AUS have emerged, two female RCTs are ongoing, the SATURN study published its 1-year outcomes, and four systematic reviews on female AUS were conducted. These findings enhance evidence levels and position novel AUS to challenge the Gold Standard.

Mitigating infections in implantable urological continence devices: risks, challenges, solutions, and future innovations. A comprehensive literature review

PURPOSE OF REVIEW

Stress urinary incontinence is a growing issue in ageing men, often following treatment for prostate cancer or bladder outflow obstruction. While implantable urological devices offer relief, infections are a significant concern. These infections can lead to device removal, negating the benefits and impacting patient outcomes. This review explores the risks and factors contributing to these infections and existing strategies to minimize them. These strategies encompass a multifaceted approach that considers patient-specific issues, environmental issues, device design and surgical techniques. However, despite these interventions, there is still a pressing need for further advancements in device infection prevention.

RECENT FINDINGS

Faster diagnostics, such as Raman spectroscopy, could enable early detection of infections. Additionally, biocompatible adjuncts like ultrasound-responsive microbubbles hold promise for enhanced drug delivery and biofilm disruption, particularly important as antibiotic resistance rises worldwide.

SUMMARY

By combining advancements in diagnostics, device design, and patient-specific surgical techniques, we can create a future where implantable urological devices offer men a significant improvement in quality of life with minimal infection risk.

[Use of implants to treat male urinary incontinence]

Treatments for benign and malignant pathologies of the prostate can compromise urine control. Urinary incontinence (UI) affects the quality of life of patients and limits their ability to carry out usual activities. The degree of impact of UI is variable and the associated discomforts make patients seek treatment for it. At the center of the management of urinary incontinence in men are surgical interventions that seek to replace the affected sphincter function through implants. The artificial urinary sphincter since its development in the 1970s has been considered the standard of treatment for UI in men. More recently artificial sphincter and slings have been shown to be effective in a selected group of incontinent men. The goals of surgical treatment of incontinence include the preservation of bladder function, the ability to improve the strength of the urinary sphincter, and to reduce or eliminate urine leakage, and thereby improve the quality of life. The aim of the article is to present various implants for the correction of male urinary incontinence.

Stress Urinary Incontinence: An Unsolved Clinical Challenge

Stress urinary incontinence is still a frequent problem for women and men, which leads to pronounced impairment of the quality of life and withdrawal from the social environment. Modern diagnostics and therapy improved the situation for individuals affected. But there are still limits, including the correct diagnosis of incontinence and its pathophysiology, as well as the therapeutic algorithms. In most cases, patients are treated with a first-line regimen of drugs, possibly in combination with specific exercises and electrophysiological stimulation. When conservative options are exhausted, minimally invasive surgical therapies are indicated. However, standard surgeries, especially the application of implants, do not pursue any causal therapy. Non-absorbable meshes and ligaments have fallen into disrepute due to complications. In numerous countries, classic techniques such as colposuspension have been revived to avoid implants. Except for tapes in the treatment of stress urinary incontinence in women, the literature on randomized controlled studies is insufficient. This review provides an update on pharmacological and surgical treatment options for stress urinary incontinence; it highlights limitations and formulates wishes for the future from a clinical perspective.

Surgical Management of Male Stress Incontinence: Techniques, Indications, and Pearls for Success

Purpose

Male stress urinary incontinence (SUI) has detrimental and long-lasting effects on patients. Management of this condition is an evolving field with multiple options for surgical treatment. We sought to review the pre-operative evaluation, intra-operative considerations, post-operative care, and future directions for treatment of male SUI.

Methods

A literature review was performed using the PubMed platform to identify peer-reviewed, English-language articles published within the last 5 years pertaining to management of male stress urinary incontinence with an emphasis on devices currently on the market in the United States including the artificial urinary sphincter (AUS), male urethral slings, and the ProACT^TM system. Patient selection criteria, success rates, and complications were compared between the studies.

Results

Twenty articles were included in the final contemporary review. Pre-operative workup most commonly included demonstration of incontinence, PPD, and cystoscopy. Definition of success varied by study; the most common definition used was social continence (0-1 pads per day). Reported rates of success were higher for the AUS than for male urethral slings (73-93% vs 70-90%, respectively). Complications for these procedures include urinary retention, erosions, infections, and device malfunction. Newer treatment options including adjustable balloon systems and adjustable slings show promise but lack long-term follow-up.

Conclusion

Patient selection remains the primary consideration for surgical decision-making for management of male SUI. The AUS continues to be the gold standard for moderate-to-severe male SUI but comes with inherent risk of need for revision. Male slings may be a superior option for appropriately selected men with mild incontinence but are inferior to the AUS for moderate and severe incontinence. Ongoing research will shed light on long-term results for newer options such as the ProACT and REMEEX systems.

Biofilms on Indwelling Artificial Urinary Sphincter Devices Harbor Complex Microbe-Metabolite Interaction Networks and Reconstitute Differentially In Vitro by Material Type

The artificial urinary sphincter (AUS) is an effective treatment option for incontinence due to intrinsic sphincteric deficiency in the context of neurogenic lower urinary tract dysfunction, or stress urinary incontinence following radical prostatectomy. A subset of AUS devices develops infection and requires explant. We sought to characterize biofilm composition of the AUS device to inform prevention and treatment strategies. Indwelling AUS devices were swabbed for biofilm at surgical removal or revision. Samples and controls were subjected to next-generation sequencing and metabolomics. Biofilm formation of microbial strains isolated from AUS devices was reconstituted in a bioreactor mimicking subcutaneous tissue with a medical device present. Mean patient age was 73 (SD 10.2). All eighteen artificial urinary sphincter devices harbored microbial biofilms. Central genera in the overall microbe−metabolite interaction network were Staphylococcus (2620 metabolites), Escherichia/Shigella (2101), and Methylobacterium-Methylorubrum (674). An rpoB mutation associated with rifampin resistance was detected in 8 of 15 (53%) biofilms. Staphylococcus warneri formed greater biofilm on polyurethane than on any other material type (p < 0.01). The results of this investigation, wherein we comprehensively characterized the composition of AUS device biofilms, provide the framework for future identification and rational development of inhibitors and preventive strategies against device-associated infection.

Adjustable Transobturator Male System (ATOMS) Infection: Causative Organisms and Clinical Profile

OBJECTIVE

To evaluate the clinical profile and the organisms producing adjustable transobturator male system (ATOMS) infection in a contemporary series.

METHODS

Multicenter retrospective study evaluating patients undergoing ATOMS explant for clinical signs of infection from a series of 902 patients treated in 9 academic institutions. Clinical and microbiological data were evaluated.

RESULTS

Infection presented in 24 patients (2.7%). The median age was 73 ± 7yrs and the median interval from ATOMS implantation to explant 11 ± 26.5mo. Infection was diagnosed within 3-months after surgery in 7(29.2%). Scrotal port erosion was present in 6 cases (25%) and systemic symptoms of parenchymatous testicular infection in 2(8.3%). The culture of the periprosthetic fluid was positive in 20(83.3%): 12(50%) Gram-negative bacteria, 9(37.5%) Gram-positive cocci and 1(4.2%) yeast. The most frequent isolates were Enterococcus and Proteus sp. (16.7% each), followed by Pseudomona sp. and S. epidermidis (12.5% each). Methicillin resistant S. aureus was detected only in 1 case (4.2%). Despite the infection 17 patients (70.8%) were satisfied with the implant and 18(75%) received a second device (11 repeated ATOMS and 7 AUS) at a median 9.7 ± 12.6mo after explant. Limitations include retrospective design and lack of microbiological cultures in ATOMS explanted for non-infective cause.

CONCLUSION

Infection of a prosthetic device is a disturbing complication. A proportion of patients with ATOMS infection is associated to scrotal port erosion and/or parenchymatous urinary tract infection. Enterococcus and Proteus sp. are the most common organisms producing ATOMS infection and this could have implications for the selection of the most appropriate surgical prophylaxis.

Artificial Urinary Sphincter Complications: Risk Factors, Workup, and Clinical Approach

PURPOSE OF REVIEW

To review risk factors for AUS complications and present a systematic approach to their diagnosis and management.

RECENT FINDINGS

Established risk factors for AUS complications include catheterization, channel TURP, pelvic radiation, urethroplasty, anticoagulation, cardiovascular disease, diabetes mellitus, frailty index, hypertension, low albumin, and low testosterone. We present our algorithm for diagnosis and management of AUS complications. Despite being the gold standard of treatment for men with SUI, major and minor complications can occur at any point after AUS insertion. Careful consideration of the urologic, medical, and operative risk factors for each patient can help prevent complications. A systematic approach to early and late complications facilitates their identification and effective management. The evaluating urologist must have a thorough understanding of potential AUS complications in order to restore quality of life in men with bothersome SUI.

Artificial urinary sphincter: current status and future directions

Urge urinary incontinence (UUI) is one of the most troublesome complications of surgery of the prostate whether for malignancy or benign conditions. For many decades, there have been attempts to reduce the morbidity of this outcome with variable results. Since its development in the 1970s, the artificial urinary sphincter (AUS) has been the “gold standard” for treatment of the most severe cases of UUI. Other attempts including injectable bulking agents, previous sphincter designs, and slings have been developed, but largely abandoned because of poor long-term efficacy and significant complications. The AUS has had several sentinel redesigns since its first introduction to reduce erosion and infection and increase efficacy. None of these changes in the basic AUS design have occurred in the past three decades, and the AUS remains the same despite newer technology and materials that could improve its function and safety. Recently, newer compressive devices and slings to reposition the bladder neck for men with mild-to-moderate UUI have been developed with success in select patients. Similarly, the AUS has had applied antibiotic coating to all portions except the pressure-regulating balloon (PRB) to reduce infection risk. The basic AUS design, however, has not changed. With newer electronic technology, the concept of the electronic AUS or eAUS has been proposed and several possible iterations of this eAUS have been reported. While the eAUS is as yet not available, its development continues and a prototype device may be available soon. Possible design options are discussed in this review.

Revisiting the penoscrotal approach to artificial urinary sphincter surgery: how does it compare to a perineal incision for initial implantation?

PURPOSE

Artificial urinary sphincters (AUS) remain the gold standard to treat male stress urinary incontinence. AUS implantation can be performed through a penoscrotal or perineal incision depending on surgeon preference.

METHODS

The present study compares initial AUS implantation through two surgical approaches focusing on outcomes of continence and revision. All AUS implanted at an academic medical center between 2000 and 2018 were retrospectively reviewed.

RESULTS

A total of 225 AUS implantations were identified, of which, 114 patients who underwent virgin AUS placement were included in the study with a mean follow-up of 28.5 months. A total of 68 patients (59.6%) had AUS placement through penoscrotal incision; while, 46 (40.4%) had a perineal incision. While operative time was significantly shorter for penoscrotal placement (98.6 min vs. 136.3 min, p = 0.001), there were no significant differences in continence rates between either surgical approach with 76.5% socially continent defined as using zero to less than 1 pad per day (safety pad). The overall rate of device erosion or infection was not significantly different between groups. However, the rate of revision or replacement was significantly higher in the perineal group (26.1% v. 8.8%; p = 0.01). On multivariate analysis, the penoscrotal incision predicted a lower rate of device revision (p = 0.01).

CONCLUSIONS

The penoscrotal approach of AUS placement is associated with shorter operative time. While we observed a lower revision rate compared to the perineal approach, there were equivalent continence outcomes.

Surgical treatment of post-prostatectomy stress urinary incontinence in adult men: Report from the 6th International Consultation on Incontinence

AIMS

To report the recommendations of the 6th International Consultation on Incontinence (ICI) on post-prostatectomy urinary incontinence.

METHODS

The 6th ICI committee on surgical treatment of urinary incontinence in men assessed and reviewed the outcomes of surgical therapy and updated the prior recommendations published in 2013. Articles from peer-reviewed journals, abstracts from scientific meetings, and literature searches by hand and electronically formed the basis of this review. The resulting guidelines were presented at the 2016 ICI meeting in Tokyo, Japan.

RESULTS

Voiding diary and pad tests are valuable for assessing quantity of leakage. Cystoscopy and/or urodynamics may be useful in guiding therapy depending on the type of incontinence and presumed etiology. Artificial Urinary Sphincter (AUS) is the preferred treatment for men with moderate to severe stress urinary incontinence (SUI) after RP. Male slings are an acceptable approach for men with mild to moderate SUI. Much discussion centers on the definition of moderate SUI. Injectable agents have a poor success rate in men with SUI. Options for recurrent SUI due to urethral atrophy after AUS implantation include changing the pressure balloon, downsizing the cuff and increasing the amount of fluid in the system. Infection and/or erosion demand surgical removal or revision of all or part of the prosthesis.

CONCLUSIONS

Although there are several series reporting the outcomes of different surgical interventions for PPUI, there is still a need for prospective randomized clinical trials. Recommendations for future research include standardized workup and outcome measures, and complete reporting of adverse events at long-term.

Current Therapeutic Strategies in Clinical Urology

The field of urology encompasses all benign and malignant disorders of the urinary tract and the male genital tract. Urological disorders convey a huge economic and patient quality-of-life burden. Hospital acquired urinary tract infections, in particular, are under scrutiny as a measure of hospital quality. Given the prevalence of these pathologies, there is much progress still to be made in available therapeutic options in order to minimize side effects and provide effective care. Current drug delivery mechanisms in urological malignancy and the benign urological conditions of overactive bladder (OAB), interstitial cystitis/bladder pain syndrome (IC/BPS), and urinary tract infection (UTI) will be reviewed herein. Both systemic and local therapies will be discussed including sustained release formulations, nanocarriers, hydrogels and other reservoir systems, as well as gene and immunotherapy. The primary focus of this review is on agents which have passed the preclinical stages of development.

Are Urine Cultures Necessary Prior to Urologic Prosthetic Surgery?

INTRODUCTION

A preoperative negative urine culture is generally advised before implantation of urologic prosthetics to prevent device infection. However, a review of the medical literature indicates sparse evidence to support this practice.

AIM

To describe outcomes for patients undergoing prosthetic implantation without preoperative urine cultures.

METHODS

The cases of men undergoing artificial urinary sphincter (AUS) and/or inflatable penile prosthesis (IPP) placement at a tertiary care center from 2007 through 2015 were reviewed. Of 713 devices implanted in 681 patients (337 AUSs in 314 patients, 376 IPPs in 367), 259 cases without preoperative urine cultures were analyzed (41%). Patients received standard perioperative antibiotics.

MAIN OUTCOME MEASURES

Device infection was diagnosed clinically. Average follow-up was 15 months.

RESULTS

Device infection occurred in 4 of 259 patients (1.5%) with no difference noted in infection rate between device groups (AUS = 3 of 174 [2%]; IPP = 1 of 85 [1%]; P = .99); this rate appears to be consistent with the infection rate of numerous other published prosthetic series. Common skin organisms were implicated as the infectious agents in half the infected devices. Only one patient (0.4%) developed an Escherichia coli infection.

CONCLUSION

This study suggests that prosthetic urologic surgery can be safely performed without preoperative urine cultures. Kavoussi NL, Viers BR, Pagilara TL, et al. Are Urine Cultures Necessary Prior to Urologic Prosthetic Surgery? Sex Med Rev 2018;6:157-161.