Urinary fistula following ileal conduit urinary diversion is rather rare, but it is associated with severe comorbidities such as abdominal infection, ileus, and metabolism impairment. Treatment is challenging, especially when it is administered following complicated pelvic organ resection and urinary diversion [6, 8-9]. For these fragile patients, the management of urinary fistula should be as minimally invasive as possible. A surgical approach is usually avoided due to postoperative complications and stickiness. In recent years, several approaches including a retrograde ureteral approach and percutaneous nephrostomy have been developed in the field of endourology to address this complicated consequence, but neither of these two options is easy to accomplish [18-21].
In this cohort, most (12/13) patients with urinary fistulas following ileal conduit urinary diversion were cured with the intra-conduit NPS, which was a time-consuming (7-11 days) but an extremely simple, safe and mini-invasive method. For these selected patients, the use of the intra-conduit NPS as a conservative treatment was compatible and tolerated, as this bedside process was nearly noninvasive. It was easy to evaluate the effect of the NPS via the decreases in abdominal/pelvic drainage and the normalized creatinine level. For the patient who experienced failure of NPS, we found that the ileal conduit was pressed by a sticky belt during the operation so that the silicon tube could not reach the end of the conduit. This may have resulted in the inability of urine to be successfully and completely suctioned. When the silicon tube was successfully placed during the second operation, the NPS worked efficiently after the operation. In fact, most urine leakage following ileal conduit urinary diversion was due to ureteroenteric anastomosis and conduit closure, so the drainage of urine out of the conduit was critical to cure urine leakage, and the intra-conduit NPS might be a good procedure to accomplish this purpose.
In recent years, an increasing number of studies have demonstrated that endourology approaches are feasible for dealing with upper urinary tract lesions. Olson L and colleagues reported that the success rate was approximately 74% (40/54) during retrograde endourological management of upper urinary tract abnormalities [10]. An antegrade percutaneous flexible endoscopic approach also demonstrated favorable outcomes [11].
In clinical practice, percutaneous nephrostomy is feasible and relatively safe for ureteroenteric anastomosis stricture. However, for patients with urine leakage following ileal conduit urinary diversion, there is often no obstruction of the ureter. Without hydronephrosis, nephrostomy is deemed to be a difficult procedure, and it is not very safe for patients following radical cystectomy/pelvic exenteration and ileal conduit urinary diversion. Therefore, this procedure should be performed only in high-volume centers by experienced surgeons. Retrograde stenting is much safer than nephrostomy, but exploration of the ureteral anastomosis is time-consuming, and mucosal edema of the ileal conduit and ureter makes the procedure difficult. Additionally, this process has a potential risk of invasive abdominal infection.
Compared to endourology approaches and transperitoneal surgery, the intra-conduit NPS is a more mini-invasive and convenient approach [9, 18]. It is a bedside procedure, but we cannot see the details of the conduit during this process, and the placement of the silicon tube might not be deep enough for certain reasons. Additionally, this procedure should be performed by a surgeon who is familiar with the operation details for each patient. If this procedure is not successful, further management, such as ureteral stenting and/or nephrostomy and even surgery might be needed. Moreover, for 8 patients, the ureteral stent was not removed when urinary fistula was diagnosed. Therefore, retrograde ureteral stenting might not be very reliable for some patients.
Although there is no recommendation of the NPS in the treatment of urinary fistula following ileal conduit urinary diversion, the NPS has often been used in complicated wounds, and its uniform negative pressure can enhance wound healing. In some complicated cases of urine leakage, the NPS was associated with a favorable outcome [15-16]. In this study, the use of the intra-conduit NPS also resulted in a favorable outcome as a conservative procedure. Therefore, the NPS might be a good alternative for curing urinary fistula following ileal conduit urinary diversion. Compared to other approaches, the intra-conduit NPS is a mini-invasive and compatible approach, and caregivers should attempt its use in clinical practice in selected patients.
This retrospective study did not strictly define the indications of the NPS, and selection bias was inevitable because all patients were in good conditions when they chose the intra-conduit NPS as a conservative treatment for urine leakage. In terms of the rarity of urine leakage, the population was limited, and no control group was recorded. As the NPS is a new approach for treating urine leakage following ileal conduit urinary diversion, advanced studies and long-term follow-up periods are needed. All of these patients were reviewed in our single center, a university-affiliated hospital. Furthermore, these patients received good supportive treatment and consistent observation and evaluation. To our knowledge, this is the largest report of the use of the NPS for urinary fistula. As a conservative treatment, the intra-conduit negative pressure system is a mini-invasive and compatible approach for selected patients with urine leakage following ileal conduit urinary diversion.