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

Abstract

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.

Assessment of the Grades of Vesicoureteral Reflux in Stented Ureters: An Experimental Study

“…Furthermore, the VUR observed in this study occurred under high intravesical pressure, up to 50 cm H 2 O, which corresponds to pressures reached during urination [27]. This, in conjunction with the low grades of reflux, results in ureteral stents providing deficient contact of the agents, such as Bacillus Calmette-Guérin or Mytomicin C, with the urothelium of the upper urinary tract during instillation, since both the surface of distribution and contact time are insufficient [9,26].…”

“…Based on our results and as mentioned by the EAU Guidelines, VUR caused by stents would therefore not be an efficient method for the instillation of topical therapy in the adjuvant treatment of low-risk upper urinary tract urothelial carcinoma [25]. VUR is not guaranteed in all individuals after the placement of a ureteral stent [26]. The quantity of patients who can benefit from this treatment is thus limited.…”

The Utility of Intraluminal Therapies in Upper Tract Urothelial Carcinoma: A Narrative Review

“…They found that those with a stent inserted for a longer period (average 21.6 days vs. immediately post-insertion) had a higher incidence of VUR, 87.5% vs. 51.4%. VUR was also correlated with volumes instilled in the bladder, with 63% having VUR induced with a bladder volume of 360 mL, whereas at 120 mL, VUR only occurred in 14% [22].…”

“…The first use of the antegrade approach via nephrostomy tube in intraluminal therapies was by Studer and colleagues in 1989, when they used this technique to administer BCG for upper tract CIS [21]. The benefits of this approach include a reduction in bladder irritation when compared to other modes of administration and the ability to easily predict the distribution of the administered agent [22]. However, the potential drawbacks of this method include the risk of seeding tumours along the nephrostomy tract, drug leakage at the nephrostomy site, bacterial colonisation and sepsis from an open system and a poorer quality of life [23].…”

3D-Printing-Assisted Extraluminal Anti-Reflux Diodes for Preventing Vesicoureteral Reflux through Double-J Stents

“…In particular, VUR induced by inserted stent can cause severe flank pain during urination or upper urinary tract infection, which has a potential hazard of pyelonephritis[ 15 , 19 - 21 ]. In addition, occurrence of reflux along the stents was reported in 51.4% of patients even after immediate insertion of ureteral stents[ 22 ]. Although VUR associated with DJ stents would not require an immediate treatment or surgery to relieve the symptoms, repetitive VUR may adversely affect patients who require long-term placement of ureteral stents[ 21 , 23 ].…”