Conduit Bladder Research Articles

Autologous micrografting improves regeneration of tissue-engineered urinary conduits in vivo

Urogenital reconstructive malformation surgery is sometimes hampered by lack of tissue for the repair. We have previously shown that autologous micrografting allows for single-staged scaffold cellularization after surgical implantation. Here, a collagen-based scaffold reinforced with biodegradable mesh and a stent was implanted as a bladder conduit in ten full-grown female minipigs. We aimed to assess short-term regenerative outcomes, safety, and feasibility of implanting tubular urinary micrografted scaffolds versus acellular controls. Five scaffolds were embedded with autologous urothelial micrografts harvested perioperatively. After six weeks, all animals were assessed by cystoscopy, CT-urography, and microanatomical assessment of the urinary conduits. The procedure proved technically feasible within the confines of a regular surgical theater, with duration-times comparable to corresponding conventional procedures. No animals experienced postoperative complications, and all implanted conduits were patent at follow-up. Improved tissue regeneration was observed in the micrografted conduits compared with the acellular controls, including increased luminal epithelialization, increased cell proliferation, decreased cell apoptosis, and increased conduit vascularization. We concluded that single-staged on-site construction and implantation of tissue engineered urinary conduits proved feasible and safe, with improved regenerative potentials in micrografted conduits. This study presents a new approach to urinary conduits, and merits further investigations for advancement towards clinical translation.

Advancing autologous urothelial micrografting and composite tubular grafts for future single-staged urogenital reconstructions

Urogenital reconstructive surgery can be impeded by lack of tissue. Further developments within the discipline of tissue engineering may be part of a solution to improve clinical outcomes. In this study, we aimed to design an accessible and easily assembled tubular graft with autologous tissue, which could be constructed and implanted as a single-staged surgical procedure within the premises of an ordinary operating room. The ultimate goals would be to optimize current treatment-options for long-term urinary diversion. Therefore, we evaluated the optimal composition of a collagen-based scaffold with urothelial micrografts in vitro, and followingly implanted the construct in vivo as a bladder conduit. The scaffold was evaluated in relation to cell regeneration, permeability, and biomechanical properties. After establishing an optimized scaffold in vitro, consisting of high-density collagen with submerged autologous micrografts and reinforced with a mesh and stent, the construct was successfully implanted in an in vivo minipig model. The construct assemblance and surgical implantation proved feasible within the timeframe of a routine surgical intervention, and the animal quickly recovered postoperatively. Three weeks post-implantation, the conduit demonstrated good host-integration with a multilayered luminal urothelium. Our findings have encouraged us to support its use in more extensive preclinical large-animal studies.

Kidney Transplant and Ileal Conduit Diversion on the Same Surgical Procedure: Clinical Case and Review of the Literature

Introduction: There are multiple causes of end-stage renal disease (ESRD). One of the most uncommon cause is the obstruction of the lower urinary tract due to the development of new endourological procedures and the improvement in clean intermittent catheterization. However, urodynamic problems that require solutions to bladder problems continue to appear that will directly affect the function of the kidney graft. Objective: Clearly state the possibility of performing a bladder conduit technique at the same time as a kidney transplant as an option for patients who undergo kidney transplantation with incompetent bladders. A clinical case is described as an example. Material and Methods: The clinical case of a patient with left cutaneous ureterostomy due to neurogenic bladder who is a candidate for renal transplant is presented. An ileal conduit type urinary diversion is performed in the same surgical act as the renal transplant. The existing literature is analyzed in relation to the different types of urinary diversion and how they affect renal function. Clinical Case and Results: Here we present a 50-year-old male with hypotonic bladder since 19th years old secondary to sacral lipectomy. He developed a progressive deterioration of renal function until he started hemodialysis program in 2018. Ileal conduit and renal transplant are performed through right pararectal incision, reimplantation of the ureter in the antimesenteric side of the intestinal loop. No increase of complications was observed in the post-transplant. The patient was discharged the 7th day after surgery. Serum creatinine at 6 months after renal transplantation 1.2mg/dl. Conclusion: Ileal conduit is a valid resource in patients with neurogenic bladders or with emptying problems whose solution puts at risk the functionality of the graft. Similar recovery is observed in time compared to a kidney transplant without ileal shunt. Post-transplant graft function was good without an increase in complications.