Humans ; Tissue Engineering ; methods ; Urinary Incontinence, Stress ; pathology ; therapy

The use of artificial urinary sphincter (AUS) for the treatment of stress urinary incontinence has become more prevalent, especially in the "prostate-specific antigen (PSA)-era", when more patients are treated for localized prostate cancer. The first widely accepted device was the AMS 800, but since then, other devices have also entered the market. While efficacy has increased with improvements in technology and technique, and patient satisfaction is high, AUS implantation still has inherent risks and complications of any implant surgery, in addition to the unique challenges of urethral complications that may be associated with the cuff. Furthermore, the unique nature of the AUS, with a control pump, reservoir, balloon cuff, and connecting tubing, means that mechanical complications can also arise from these individual parts. This article aims to present and summarize the current literature on the management of complications of AUS, especially urethral atrophy. We conducted a literature search on PubMed from January 1990 to December 2018 on AUS complications and their management. We review the various potential complications and their management. AUS complications are either mechanical or nonmechanical complications. Mechanical complications usually involve malfunction of the AUS. Nonmechanical complications include infection, urethral atrophy, cuff erosion, and stricture. Challenges exist especially in the management of urethral atrophy, with both tandem implants, transcorporal cuffs, and cuff downsizing all postulated as potential remedies. Although complications from AUS implants are not common, knowledge of the management of these issues are crucial to ensure care for patients with these implants. Further studies are needed to further evaluate these techniques.
Atrophy ; Humans ; Postoperative Complications/therapy* ; Prosthesis Failure ; Prosthesis Implantation ; Prosthesis-Related Infections/therapy* ; Urethra/pathology* ; Urethral Diseases/therapy* ; Urethral Stricture/surgery* ; Urinary Incontinence, Stress/surgery* ; Urinary Sphincter, Artificial

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.
Amniotic Fluid/*cytology ; Animals ; Biological Markers/metabolism ; Cell Differentiation ; Cell Lineage ; Cell Transformation, Neoplastic ; Cells, Cultured ; Coculture Techniques ; Female ; Gene Expression Regulation ; Humans ; Immunohistochemistry ; Mice ; Mice, Inbred ICR ; Regeneration ; *Stem Cell Transplantation ; Stem Cells/*cytology/metabolism ; Urethra/physiology ; Urinary Incontinence, Stress/pathology/*therapy ; Urodynamics