[Treatment of ureteral fistula and stricture following renal transplantation with Boari flap].

To estimate the incidence rate of ureteral fistula and stricture after kidney transplantation, and to evaluate the effect of bladder flap (Boari flap) on ureteral complication of the transplanted kidney. 
 Methods: The clinical data and risk factors from 270 recipients of renal transplantation, who came from the Centre of Organ Transplantation, Xiangya Hospital, Central South University from January 2010 to January 2015, were retrospectively analyzed. The surgical management included Boari flap for ureteral reconstruction, neoureterocystostomy and endoscopic therapy with double-J (DJ) stent placement. Surgical proceeding and the effectiveness were evaluated.
 Results: The incidence rate of ureteral fistula following renal transplantation was 3.3%. The risk factors for ureteral fistula included elder donor age (P<0.05), delayed graft function (P<0.01), bladder spasm (P<0.05), and multiple renal arteries in allograft (P<0.01). Four cases were recovered after conservative treatment, and the other 5 cases were recovered after the treatment with Boari flap for ureteric reconstruction. The incidence rate of ureteral stricture was 4.4%. The risk factors for ureteral stricture included elder donor age (P<0.05), delayed graft function (P<0.05), cystospasm (P<0.05), ureteral fistula (P<0.01) and multiple renal arteries in allograft (P<0.01). Four cases underwent endoscopic therapy, 2 of them carried out percutaneous nephrostomy followed by antegrade DJ stent placement and the other 2 patients by retrograde DJ stent placement under ureteroscopy. Eight patients underwent surgery, 6 of them was treated by Boari flap for ureteral reconstruction and 2 patients were treated by neoureterocystostomy. All the patients recovered after surgical management.
 Conclusion: The ureteral complications after renal transplantation include ureteral fistula and stricture. Although the total incidence is low, the complications can result in adverse effects to the graft function and the life quality of the recipients. The risk factors for ureteral complication include elder donor age, delayed graft function, cystospasm, and multiple renal arteries in allograft. Ureteral fistula is the risk factor for ureteral fracture. Boari flap for ureterial reconstruction is an effective method in the treatment of the ureteral fistula and stricture.