Is ureteral stent an effective way to deliver drugs such as bacillus Calmette-Guérin to the upper urinary tract? An experimental study

摘要

Background: We aim to evaluate the distribution in the upper urinary tract of intravesical-delivered fluids, after inducing vesicoureteral reflux (VUR) with a double J stent. Methods: In group 1 (n = 35) patients were maintained in a 20° Trendelenburg position and were evaluated after immediate insertion of ureteral stent, while in group 2 (n = 16) patients were evaluated after several days with ureteral stent placement. Patients in both groups were submitted to a cystogram with progressive volumes of iodine contrast and were evaluated according to VUR of contrast medium to the renal pelvis. Additionally, in group 2 visual confirmation was performed by endoscopic inspection of upper tract mucosal impregnation with methylene blue. Results: In group 1, after immediate insertion of ureteral stent reflux occurred in 51.4% (n = 18/35), and after several days with ureteral stent placement reflux was observed in 87.5% (n = 14/16) of patients. Reflux was progressively more frequent according to increasing bladder volume (p 0.001). At 60?ml bladder volume no reflux was observed, while at 120?ml, 180?ml, 240?ml, 300?ml and 360?ml bladder volume reflux was observed in 14%, 25%, 41%, 55% and 63% of patients, respectively. Conclusion: Retrograde delivery of fluids such as bacillus Calmette-Guérin to the upper urinary tract through double J stents can be effective; however, it is mainly effective after several days with ureteral stent and relatively large volumes might be instilled into the bladder.