Stress urinary incontinence in women

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 Some of the injectable bulking agents have been withdrawn from the market because of their unfavorable adverse effect profile.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.

Pre-clinical efficacy and safety evaluation of human amniotic fluid-derived stem cell injection in a mouse model of urinary incontinence

PURPOSE

Stem cell-based therapies represent new promises for the treatment of urinary incontinence. This study was performed to assess optimized cell passage number, cell dose, therapeutic efficacy, feasibility, toxicity, and cell trafficking for the first step of the pre-clinical evaluation of human amniotic fluid stem cell (hAFSC) therapy in a urinary incontinence animal model.

MATERIALS AND METHODS

The proper cell passage number was analyzed with hAFSCs at passages 4, 6, and 8 at week 2. The cell dose optimization included 1×10⁴, 1×10⁵, and 1×10⁶ cells at week 2. The in vivo cell toxicity was performed with 0.25×10⁶, 0.5×10⁶, and 1×10⁶ cells at weeks 2 and 4. Cell tracking was performed with 1×10⁶ cells at weeks 2 and 4.

RESULTS

The selected optimal cell passage number was smaller than 6, and the optimal cell dose was 1×10⁶ for the mouse model. In our pre-clinical study, hAFSC-injected animals showed normal values for several parameters. Moreover, the injected cells were found to be non-toxic and non-tumorigenic. Furthermore, the injected hAFSCs were rarely identified by in vivo cell trafficking in the target organs at week 2.

CONCLUSION

This study demonstrates for the first time the pre-clinical efficacy and safety of hAFSC injection in the urinary incontinence animal model and provides a basis for future clinical applications.

Human amniotic fluid stem cell-derived muscle progenitor cell therapy for stress urinary incontinence

The most promising treatment for stress urinary incontinence can be a cell therapy. We suggest human amniotic fluid stem cells (hAFSCs) as an alternative cell source. We established the optimum in vitro protocol for the differentiation from hAFSCs into muscle progenitors. These progenitors were transplanted into the injured urethral sphincter and their therapeutic effect was analyzed. For the development of an efficient differentiation system in vitro, we examined a commercial medium, co-culture and conditioned medium (CM) systems. After being treated with CM, hAFSCs were effectively developed into a muscle lineage. The progenitors were integrated into the host urethral sphincter and the host cell differentiation was stimulated in vivo. Urodynamic analysis showed significant increase of leak point pressure and closing pressure. Immunohistochemistry revealed the regeneration of circular muscle mass with normal appearance. Molecular analysis observed the expression of a larger number of target markers. In the immunogenicity analysis, the progenitor group had a scant CD8 lymphocyte. In tumorigenicity, the progenitors showed no teratoma formation. These results suggest that hAFSCs can effectively be differentiated into muscle progenitors in CM and that the hAFSC-derived muscle progenitors are an accessible cell source for the regeneration of injured urethral sphincter.

Emerging drugs for treatment of urinary incontinence

IMPORTANCE OF THE FIELD

Urinary incontinence (UI) is a common problem and there are so many advances done in the field to help treat this common and distressing condition.

AREAS COVERED IN THIS REVIEW

In this article we have tried to give an overview about current and emerging drugs available for the management of UI. WHAT THE READERS GAIN: Reading the article will help to fill the knowledge gap regarding drugs available for treatment of UI.

TAKE HOME MESSAGE

Anti-muscarinic drugs remain the first-line treatment of overactive bladder (OAB) and a favorable efficacy/tolerability:safety ratio can be confirmed, but adverse effects and decreasing compliance remains an issue. Promising new alternatives are emerging but require further controlled studies to confirm their place in treatment of OAB. Surgery is still the mainstay for treatment of stress incontinence although duloxetine is the only drug licensed for this indication.