Massive prolapse of the urethral mucosa following periurethral injection of calcium hydroxylapatite for stress urinary incontinence

Foreign body granuloma development after calcium hydroxylapatite injection for stress urinary incontinence: A literature review and case report

Objectives

To present a case of foreign body granuloma (FBG) development after injection of calcium hydroxylapatite as a urethral bulking agent and to review all documented cases of this phenomenon in the literature.

Methods

We analyzed a new case of calcium hydroxylapatite-induced FBG. We also conducted a literature review of the PubMed, Embase, CINAHL, and Web of Science databases through March 2022. Reports were included if they contained stress urinary incontinence patients that developed an FBG after calcium hydroxylapatite injection. The cases were reviewed for presenting symptoms, patient demographics, granuloma details, and surgical treatment.

Results

We screened 250 articles and included six articles between 2006 and 2015 in addition to the present case. The median age of the patients was 65.5 years (range 45-93), and all patients were female. The most common presenting symptoms and the proportion of patients affected were difficulty voiding (4/8), recurrent urinary incontinence (3/8), and dyspareunia (2/8). The median time between the first CaHA injection and discovery of the FBG was 5 months (range 1-50). The median longest dimension of the FBGs was 1.85 cm (range 1.0-3.0). The 8 masses observed were evenly distributed throughout the urethra, with 3 in the bladder neck, 2 in the midurethra, and 3 in the distal urethra. Surgical excision was the predominant management choice, with some variation in technique.

Conclusions

Severe, persistent lower urinary tract symptoms after calcium hydroxylapatite injection may indicate an FBG, which has been successfully managed with surgical excision.

Update on Urethral Bulking for Stress Urinary Incontinence in Women

PURPOSE OF REVIEW

Urethral bulking agents are an effective treatment for stress urinary incontinence in select females. The material and techniques used for urethral bulking are constantly evolving. With the introduction of several new agents, there is an ongoing debate over which agent is the most effective, durable, and safe.

RECENT FINDINGS

Current available bulking agents include Bulkamid®, Macroplastiue®, Durasphere®, Coaptite®, or Urolastic®. Each of these agents has its own biophysical properties that affect its efficacy and safety. Evidence evaluating bulking agents has increased over time but there is no definitive data that suggest superiority of one agent over another. The ideal urethral bulking agent for female stress incontinence has yet been identified. Currently available agents have acceptable short-term and medium-term efficacy with few adverse events.

Long-term complications of bulking agents in the treatment of stress urinary incontinence: Results of a national survey

Introduction and Objectives:

Bulking agents have been used for decades as an alternative treatment for patients with stress urinary incontinence who are not appropriate for surgery. Despite this their long-term complications are poorly documented and can be misdiagnosed. This paper presents a literature review and the results of a national survey of members of the Section of Female, Neurological and Urodynamic Urology (FNUU) of the British Association of Urological Surgeons (BAUS) identifying the common long-term complications of widely used bulking agents in clinical practice.

Methods:

Following a comprehensive literature review an electronic survey was sent to members of the BAUS Section of FNUU. Data included hospital trust, use of urethral bulking agents (including type), the approximate number of procedures performed and whether any long-term complications had been observed and managed in their practice. Long-term complications were defined as those arising more than 12 months after treatment.

Results:

The literature review revealed multiple case reports of complications secondary to bulking agent injection but no high-level evidence regarding frequency or severity. The survey revealed complications including granulomas, erosions, abscesses and misdiagnoses of urethral diverticula and calculi formation. 88% of urologists who responded to the survey had performed a urethral bulking agent injection and 51% of urologists had observed or treated a long-term complication, some many decades after injection.

Conclusion:

Patients should be made aware of possible long-term complications of what appears to be a minimally invasive procedure in order for them to make an informed choice about treatment options.

Level of evidence:

Not applicable

Use of bioactive extracellular matrix fragments as a urethral bulking agent to treat stress urinary incontinence

Injection of urethral bulking agents is a low-risk, minimally invasive surgical procedure to treat stress urinary incontinence (SUI). In this study, we developed a promising injectable bulking agent comprising extracellular matrix fragments of adipose-derived stem cell sheets (ADSC ECM) and investigated its effectiveness in urethral bulking therapy. The structural integrity and proteins of ADSC sheet ECM were well retained in decellularized ADSC ECM fragments. To locate transplanted ADSC ECM fragments, they were labeled with ultrasmall super-paramagnetic iron oxide nanoparticles, which enabled in vivo monitoring after implantation in a SUI rat model for up to 4 weeks. When ADSC ECM fragments were injected into the rat urethra, they became fully integrated with the surrounding tissue within 1 week. Four weeks after transplantation, host cells had regenerated within the ADSC ECM fragment injection area. Moreover, new smooth muscle tissue had formed around the ADSC ECM fragments, as confirmed by positive staining of myosin. These results indicate that injection of ECM fragments may be a promising minimally invasive approach for treating SUI.

Particulate Versus Non-Particulate Bulking Agents In The Treatment Of Stress Urinary Incontinence

Stress urinary incontinence (SUI) has been treated surgically with the midurethral sling but in recent years, this option has come under scrutiny and the risk-benefit balance continues to be reviewed. The low-risk alternative for women with uncomplicated SUI is the bulking agent, which aims to achieve continence through coaptation of the urethra. Two classes of bulking agents can be identified: those made from solid microparticles in an absorbable liquid or gel carrier (particulate agents) and those comprising a homogenous gel (non-particulates) that resists absorption. Polydimethylsiloxane®, carbon-coated zirconium oxide®, calcium hydroxyapatite® and polyacrylate polyalcohol copolymer® are currently marketed particulate agents. With the exception of calcium hydroxyapatite, the particles are non-degradable. Each agent achieves its long-term bulking effect through reactive changes around the persisting particles while the carrier volume is lost. Bulkamid® is a non-particulate agent with the bulking effect resulting from the volume of gel injected. The lasting network of fine fibers formed by the host tissue anchors the gel in situ. Foreign-body granulomas, erosion and migration/material extrusion and loss of bulk have been observed in connection with the particle-based products. Bulkamid may be mechanistically less liable to these events; however, there are minimal data directly comparing the two types of bulking agent. The question of durability is inevitable based on their differing modes of action.

Complications of urethral bulking therapy for female stress urinary incontinence

AIMS

To review, report, and discuss the complications associated with urethral bulking therapy in female stress urinary incontinence.

METHODS

An extensive nonsystematic literature review on complications associated with injectable bulking agents used in the clinical practice was conducted. We reviewed articles published in English and indexed in the PubMed, Embase, and Google Scholar databases. Original articles, case reports, and case series were taken into consideration. Data regarding the safety of injectable bulking agents and the complications associated with their utility within the context of urethral bulking therapy for female stress urinary incontinence were extracted and discussed.

RESULTS

Approximately, 1/3 of the patients experience some type of a complication after urethral bulking therapy. The majority of these complications are of low grade, transient, do not necessitate additional surgical intervention, and amenable to treatment with conservative measures such as clean intermittent catheterization and antibiotics. However, more serious complications such as abscess formation, delayed hypersensitivity reactions, and vaginal erosion have been reported. Some of the injectable bulking agents have been withdrawn from the market because of their unfavorable adverse effect profile.

CONCLUSIONS

Urethral bulking therapy can be considered as a low-risk procedure. However, it is not without complications which can be severe in rare instances. The search for the ideal urethral bulking agent is ongoing and future comparative studies assessing the safety and efficacy of these compounds in randomized controlled settings are warranted.

Injection of Urethral Bulking Agents

Urethral injection is a safe and minimally invasive method of treating female stress urinary incontinence with multiple bulking agents currently commercially available. Although there are numerous studies that demonstrate efficacy, long-term success is not yet proven. This article aims to describe the mechanism of action and properties of various agents, patient selection factors, available techniques for injection, outcomes of urethral injections, and complications associated with the procedure.

Injectable treatments for female stress urinary incontinence

The use of injectable agents for the treatment of stress urinary incontinence (SUI) is an option for female patients who are unwilling to undergo surgery, or have concurrent conditions or diseases that render surgical treatment unsuitable. To be effective for SUI, an injectable agent must be nonimmunogenic, hypoallergenic, biocompatible, permanent, nonerosive, nonmigratory and painless. It must also heal with minimal fibrosis, possess a long-term bulking effect, and be easily stored and handled. Glutaraldehyde cross-linked bovine collagen (Contigen), silicone polymers (Macroplastique), Durasphere, calcium hydroxyapatite (Coaptite), polyacrylamide hydrogel (Aquamid, Bulkamid), Permacol, and stem cell therapy have been used as injectable agents. Patients must be informed that treatment with injectable agents is not as effective as surgical treatment, and that such agents might necessitate additional and repeated administrations in order to achieve the desired therapeutic effect.

Efficacy and safety of polyacrylamide hydrogel for the treatment of female stress incontinence: a randomized, prospective, multicenter North American study

PURPOSE

Bulkamid® is a new polyacrylamide hydrogel bulking agent for stress urinary incontinence that is injected in the urethral submucosa using a specifically designed device. We evaluated the safety and efficacy of Bulkamid vs Contigen® collagen gel for stress urinary incontinence or stress predominant mixed urinary incontinence.

MATERIALS AND METHODS

This was a single-blind, randomized, prospective, 33-center, 2-arm parallel study of hydrogel vs collagen gel with followup to 1 year. At baseline patients underwent physical examination and bladder testing, and completed quality of life questionnaires and bladder diaries. After randomization patients could receive up to 3 injections at 1-month intervals. Patients were assessed 3, 6, 9 and 12 months after bulking. They completed bladder diaries and quality of life questionnaires, and pad weight was tested. At the last visit Valsalva leak point pressure was measured. Subjective and objective incontinence outcomes and adverse events were compared.

RESULTS

Of the 345 women 229 were randomized to hydrogel and 116 were randomized to collagen gel. At 12 months a 50% or greater decrease in leakage and incontinence episodes was seen in 53.2% and 55.4% of patients who received hydrogel and collagen gel, respectively. At 12 months 47.2% of patients with hydrogel and 50% with collagen gel reported zero stress incontinence episodes, and 77.1% and 70%, respectively, considered themselves cured or improved. Major adverse events were rare in each group.

CONCLUSIONS

Bulkamid is not inferior to Contigen. It has a favorable, persistent effect on stress urinary incontinence with a low risk of serious adverse events. Bulkamid is a new, simple, office based bulking system that shows promise as a treatment in women with stress urinary incontinence, particularly since Contigen is no longer commercially available.

Bulking agents: a urogynecology perspective

A bulking agent is a material injected into the wall of the urethra to improve urethral coaptation in women suffering from stress incontinence. The concept was initially described in the 1930s when sodium morrhuate and paraffin were used to augment urethral resistance. Sclerosing agents were also used for inducing permanent urethral scaring to improve urinary leakage. Eventually, collagen and autologous fat were found to be efficacious, and only collagen demonstrated proven safety and endured extensive testing, becoming the gold standard for injectable agents. Since then, multiple other products have been developed by the industry, each with its particular success rates and complications.

Urethral bulking: a urology perspective

Urethral bulking therapy (UBT) is a minimally invasive procedure for stress urinary incontinence that is beneficial for properly selected patients. Many different materials are available for UBT, although none fulfill all the qualities of an ideal agent. In general, short-term clinical results are encouraging; however, over longer follow-up, results are disappointing and retreatment is often necessary. Proper patient selection and management of patient expectations are paramount to successful application of UBT.

Nonsurgical transurethral radiofrequency collagen denaturation: results at three years after treatment

Objective. To assess treatment efficacy and quality of life in women with stress urinary incontinence 3 years after treatment with nonsurgical transurethral radiofrequency collagen denaturation. Methods. This prospective study included 139 women with stress urinary incontinence due to bladder outlet hypermobility. Radiofrequency collagen denaturation was performed using local anesthesia in an office setting. Assessments included incontinence quality of life (I-QOL) and urogenital distress inventory (UDI-6) instruments. Results. In total, 139 women were enrolled and 136 women were treated (mean age, 47 years). At 36 months, intent-to-treat analysis (n = 139) revealed significant improvements in quality of life. Mean I-QOL score improved 17 points from baseline (P = .0004), while mean UDI-6 score improved (decreased) 19 points (P = .0005). Conclusions. Transurethral collagen denaturation is a low-risk, office-based procedure that results in durable quality-of-life improvements in a significant proportion of women for as long as 3 years.

The treatment of female stress urinary incontinence: an evidenced-based review

OBJECTIVE

To review the literature on the surgical and nonsurgical treatment options for stress urinary incontinence in women, focusing exclusively on randomized clinical trials and high quality meta-analyses.

MATERIALS AND METHODS

A computer-aided and manual search for published randomized controlled trials and high quality meta-analyses investigating both conservative and surgical treatment options for stress urinary incontinence. In the case of a treatment that is not studied in these formats large case series have been used.

RESULTS

Articles were reviewed and the results summarized on pelvic floor physical therapy, pharmacotherapy, bulking agents, and surgery (open and minimally invasive).

CONCLUSION

There are numerous high quality studies in the literature. It can be difficult to make definitive conclusions on the most appropriate treatment options due to the variability in the outcomes used to define success in these articles. There is also a dire lack of studies evaluating and comparing the surgical options for patients with intrinsic sphincter deficiency.

"Vaginal" bleeding in prepubertal age: a rare scaring riddle, a case of the urethral prolapse and review of the literature

The entities responsible for isolated vaginal bleeding are a broad spectrum of diseases. Vaginal bleeding in a prepubertal child is always treated as an alarming symptom both by parents and professionals. Most often, one of the first hypotheses is that a sexual abuse may be occurred and the clinical work up is oriented to explore it and eventually confirm or substantiante another diagnosis. Among the possible differential diagnosis urethral prolapse has to be considered. We report the case of a 6 years-old Caucasian girl referred to our Service for a mild vaginal bleeding and with the suspicion of sexual abuse, excluded after the confirmation of the presence of urethral prolapse. The clinical picture and workup are described and compared with a review of the international literature on the issue.

An open multicenter study of polyacrylamide hydrogel (Bulkamid®) for female stress and mixed urinary incontinence

Introduction

Polyacrylamide hydrogel (PAHG, Bulkamid®) is a promising urethral bulking agent. This multicenter study was carried out to evaluate safety and efficacy of Bulkamid® for female stress and mixed urinary incontinence.

Methods

Submucosal injection of Bulkamid® was performed in 135 women with urinary incontinence (stress, 67; mixed, 68) followed for 12 months. Forty-seven had a reinjection (35%).

Results

At 12 months, the subjective response rate was 66%. Incontinence episodes/24 h and urine leakage g/24 h decreased significantly (from 3.0 to 0.7 and 29 g to 4 g, respectively). Additionally, the median International Consultation on Incontinence Questionnaire score was reduced to approximately 50%, and the overall quality of life visual analogue scale score was decreased significantly (from 72 to 20). Efficacy was very similar between patients with stress and mixed incontinence. Thirty treatment-related adverse events were registered. The most frequent was urinary tract infection (n = 10). No polyacrylamide hydrogel-specific adverse events were seen.

Conclusions

Bulkamid® is an effective and safe bulking agent in women with stress or mixed incontinence.

Polymeric Microspheres for Medical Applications

Synthetic polymeric microspheres find application in a wide range of medical applications. Among other applications, microspheres are being used as bulking agents, embolic- or drug-delivery particles. The exact composition of the spheres varies with the application and therefore a large array of materials has been used to produce microspheres. In this review, the relation between microsphere synthesis and application is discussed for a number of microspheres that are used for different treatment strategies.

Urethral bulking agents: techniques and outcomes

Stress urinary incontinence is a common health problem affecting women and interfering with their quality of life. The use of bulking agents for urethral augmentation seems to be a beneficial way of restoring continence in these patients while avoiding the risk of surgical intervention. Many agents are available for injection, but the ideal choice should be durable, nonmigratory, and hypoallergenic, while evoking healing with minimal scarring. We reviewed the literature to provide an update on the best techniques of bulking agent injection, to describe the different available injectable agents, and to give their outcome and possible complications.

Stress urinary incontinence in women

Stress urinary incontinence (SUI) is a major health issue that affects millions of patients each year. Traditionally, surgical procedures such as slings or bladder neck suspension were the only options to treat this condition. In recent years, multiple minimally invasive options to treat SUI were introduced into the market. These include bulking agents, injection of stem cells into the rhabdosphincter, and adjustable continence therapy devices. These procedures are simple, minimally invasive, and well tolerated by patients. This article reviews the benefits, efficiency, side effects, and complications of these minimally invasive methods for treatment of SUI.

Benign masses of the female periurethral tissues and anterior vaginal wall

Due to their rarity, benign masses of the periurethral tissues and anterior vaginal wall are poorly understood. Arriving at the proper evaluation and treatment is challenging because many of these masses have similar presenting signs and symptoms, as well as overlapping differential diagnoses. The literature regarding these lesions mainly consists of level III evidence, mostly involving case reports and series. Clinical management has traditionally been based on established surgical principles and expert opinion. This review presents the pertinent embryologic and anatomic background for these benign masses, as well as other pertinent etiological processes. Furthermore, the most current evidence is reviewed regarding the differential diagnosis, evaluation, and treatment for each mass.

Bulking agent induced early urethral prolapse after distal urethrectomy

Urethral prolapse after injection therapy for incontinence is rare. We report a case of early urethral prolapse in an adult woman with urinary incontinence secondary to distal urethrectomy treated with calcium hydroxylapatite (Coaptite).

Emerging periurethral bulking agents for female stress urinary incontinence: is new necessarily better?

Bulking therapy for stress urinary incontinence in women continues to evolve from the standpoint of material science. Several new materials have recently been subjected to clinical trials with the aim of assessing efficacy and safety of these agents for possible device registration. These new additions run the gamut of biologic to synthetic materials, including re-engineered carbon-coated zirconium beads, ethylene vinyl copolymer, calcium hydroxylapatite, silicone, and hyaluronic acid. Trial design and results reporting for bulking agents has also evolved, with the addition of quality-of-life and patient approbation assessments now being included with outcomes for incontinence reduction and adverse events recording. The new agents and recent studies are reviewed within a context of the prior evidence that has supported the use of the bulking strategy for management of symptomatic stress incontinence. Several recent trials have also compared bulking agents with surgical interventions from effectiveness, approbation, and cost vantage points so as to better determine the reasonability of bulking agent use in an era of minimally invasive incontinence surgery.