Abstract No. 166 Institution-wide experience with in-house modified occluding nephroureteral stents

Abstract

To describe our institution-wide experience with in-house modified occluding percutaneous nephroureteral stents Current reversible therapies for temporary urinary diversion include percutaneous nephrostomies (PCN) and percutaneous internal/external nephroureteral (PCNU) stents. These methods offer external drainage of urine, thereby decreasing the flow down the ureter and into the bladder. However, some patients may require better urinary diversion than PCNs and PCNU stents can offer. At our institution, a mechanically modified occluding percutaneous nephroureteral (MOPNU) stent has been used. The modification for MOPNU stent is accomplished by using a heating element to soften and seal a standard PCNU catheter which has been cut across its mid-portion between its two loops. The modified catheter is then inserted via a peel-away sheath. In a retrospective review of subjects receiving a MOPNU stent between October 2006 and December 2019 at our institution, a total of 85 subjects were identified, including 29 females and 56 males. The mean age was 64.7(SD = 14.9), ranging from 27.3 to 92.7. The most common indications for MOPNU stent placement were urinary diversion for urinary tract fistulas, ileal conduit complications, iatrogenic urinary injury and persistent hematuria. Of these patients, 69 (81%) had a history of cancer and 4 (5%) had history of inflammatory bowel disease. The primary endpoint was durable treatment at 6 weeks defined as complications free complete urinary diversion. The secondary endpoints were durable treatment at 3, 6 months and 1 year. There were 52 (61.2%) subjects with a durable treatment at 6 weeks, 31 (36.5%) at 3 months, 17 (20.0%) at 6 months, and 12(14.1%) at 1 year. No clear predictors of failure or success were identified. Sixty-three patients were converted from PCN to MOPNU stent, while twenty-two patients had MOPNU stents placed in a primary fashion. MOPNU placement had a 100% success rate. During the entire duration of treatment 10 subjects (11.9%) had tube blockage, 8 (9.5%) had urine leak, 8 (9.5%) had decreased tube output, 13 (15.5%) had a hematuria, 20 (23.8%) had tube dislodgement, 28 (33.7%) were diagnosed with a UTI, 13 (15.5%) needed revision for unknown reason. Having a tool for reversible urinary diversion is invaluable to treat certain medical conditions. MOPNU stents can provide temporary, safe, reversible urinary diversion in patients requiring better urinary diversion than PCNs and PCNUs can offer.