Acute Kidney Injury, Calculous Anuria, Obstructive Uropathy, Upper Ureteral Stone
Conditions
Keywords
Percutaneous nephrostomy, Double-J ureteral stent, Retrograde intrarenal surgery
Brief summary
Calculous anuria caused by obstructing upper ureteral stones in a solitary functioning kidney is a urological emergency requiring urgent decompression. Both retrograde JJ ureteral stenting and percutaneous nephrostomy are commonly used emergency drainage methods. However, limited evidence is available regarding whether the initial drainage method affects subsequent definitive flexible ureteroscopy/retrograde intrarenal surgery outcomes. This multicenter prospective randomized controlled trial will compare emergency JJ ureteral stent drainage versus percutaneous nephrostomy drainage in adult patients presenting with calculous anuria due to a single upper ureteral stone in a solitary functioning kidney. After renal functional improvement, clinical stabilization, and appropriate urine culture management, all participants will undergo standardized definitive flexible ureteroscopy/retrograde intrarenal surgery. The study will assess renal functional recovery, first-session surgical success, stone-free rate, operative parameters, complications, and microbiological outcomes.
Detailed description
This is a multicenter prospective randomized controlled trial comparing two emergency drainage strategies before definitive flexible ureteroscopy/retrograde intrarenal surgery in patients presenting with calculous anuria. Adult patients with calculous anuria caused by a single upper ureteral stone in a solitary functioning kidney will be assessed for eligibility. Eligible participants will be randomized in a 1:1 ratio to emergency retrograde JJ ureteral stent drainage or emergency percutaneous nephrostomy drainage. Randomization will be performed using a computer-generated random sequence, with allocation concealment using sequentially numbered opaque sealed envelopes. Participants assigned to the JJ stent group will undergo emergency retrograde placement of a 6 Fr JJ ureteral stent under cystoscopic guidance. Participants assigned to the percutaneous nephrostomy group will undergo emergency ultrasound-guided placement of an 8 Fr nephrostomy tube. After drainage, participants will be monitored for urine output recovery, renal functional improvement, symptom relief, and clinical stabilization. Definitive flexible ureteroscopy/retrograde intrarenal surgery will be scheduled after renal functional improvement, clinical stabilization, and negative or appropriately treated urine culture. The definitive procedure will be performed using a standardized operative strategy. Ureteral access sheath use, successful insertion, need for adjunctive ureteral maneuvers, operative time, laser time, fluoroscopy time, postoperative stenting, complications, and hospital stay will be recorded. The primary outcome is renal functional recovery after initial drainage and definitive surgery, assessed using serial serum creatinine measurements at presentation, 24 to 48 hours after drainage, before definitive surgery, postoperative day 1, and follow-up. Secondary outcomes include first-session definitive surgery success, stone-free rate, technical operative variables, intraoperative and postoperative complications, microbiological culture patterns, and predictors of surgical success or postoperative complications. Participants will be followed for approximately one month after definitive surgery by clinical assessment, laboratory evaluation, and imaging for assessment of renal function, complications, and stone clearance.
Interventions
PROCEDUREInitial JJ Ureteral Stent Drainage
Retrograde cystoscopic placement of a 6 Fr JJ ureteral stent for initial upper urinary tract decompression in patients presenting with calculous anuria due to a single upper ureteral stone in a solitary functioning kidney. After renal functional improvement, clinical stabilization, and appropriate urine culture management, participants will undergo standardized definitive flexible ureteroscopy/retrograde intrarenal surgery.
PROCEDUREInitial Percutaneous Nephrostomy Drainage
Ultrasound-guided placement of an 8 Fr percutaneous nephrostomy tube for initial upper urinary tract decompression in patients presenting with calculous anuria due to a single upper ureteral stone in a solitary functioning kidney. After renal functional improvement, clinical stabilization, and appropriate urine culture management, participants will undergo standardized definitive flexible ureteroscopy/retrograde intrarenal surgery.
Sponsors
Beni-Suef University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Masking description
Outcome assessors evaluating postoperative laboratory results, imaging-based stone-free status, complications, and microbiological outcomes will be blinded to the initial drainage allocation whenever feasible. Participants, care providers, and operating surgeons cannot be blinded because the assigned drainage method is clinically evident.
Intervention model description
Participants will be randomized in a 1:1 ratio to one of two emergency drainage strategies: retrograde JJ ureteral stent drainage or percutaneous nephrostomy drainage. After renal functional improvement, clinical stabilization, and appropriate urine culture management, all participants will undergo standardized definitive flexible ureteroscopy/retrograde intrarenal surgery.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Adults aged 18 years or older. * Calculous anuria secondary to a single upper ureteral stone. * Solitary functioning kidney, whether anatomical or functional. * Single upper ureteral stone confirmed by non-contrast computed tomography. * Stone size from 6 mm to 20 mm in maximum diameter. * Patient considered suitable for either initial JJ ureteral stent drainage or percutaneous nephrostomy drainage. * Candidate for definitive treatment by flexible ureteroscopy/retrograde intrarenal surgery. * Documented renal functional improvement and clinical stabilization before definitive RIRS. * Negative or appropriately treated urine culture before definitive RIRS. * Ability and willingness to provide written informed consent.
Exclusion criteria
* Multiple stones or bilateral stones not fitting the solitary-kidney study design. * Renal pelvic, distal ureteral, or multiple ipsilateral stones. * Stone burden greater than 20 mm. * Septic shock, hemodynamic instability, or need for emergency dialysis at presentation. * Pyonephrosis requiring a non-randomized drainage decision. * Anatomical abnormalities affecting endoscopic access, such as horseshoe kidney, pelvic kidney, ureterocele, or ureteral stricture. * Previous ipsilateral ureteral reconstructive surgery. * Uncorrected coagulopathy. * Pregnancy. * Genitourinary malignancy. * Inability to complete follow-up.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Serum Creatinine From After Initial Drainage to After Definitive RIRS | From 24-48 hours after initial drainage to postoperative day 1 after definitive RIRS | Serum creatinine will be measured in mg/dL at 24-48 hours after initial drainage and on postoperative day 1 after definitive tratment of stone by retrograde intrarenal surgery. The primary outcome will compare the change in serum creatinine from the post-drainage value to the post-RIRS value between the JJ ureteral stent drainage group. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| First-Session Definitive RIRS Success Rate | During the definitive RIRS procedure | First-session definitive RIRS success will be defined as successful completion of flexible ureteroscopy/retrograde intrarenal surgery for the target upper ureteral stone in the planned first definitive session without the need to abort the procedure or schedule an additional unplanned definitive stone procedure during the same treatment pathway. The proportion of participants achieving first-session success will be compared between the JJ ureteral stent drainage group and the percutaneous nephrostomy drainage group. |
| Stone-Free Rate After Definitive RIRS | 4 weeks after definitive RIRS | Stone-free rate will be defined as the proportion of participants with no detectable residual target stone fragment on follow-up non-contrast computed tomography performed 4 weeks after definitive flexible ureteroscopy/retrograde intrarenal surgery. Stone-free rate will be compared between the JJ ureteral stent drainage group and the percutaneous nephrostomy drainage group |
| During the definitive RIRS procedure | During the definitive RIRS procedure | Total operative time will be measured in minutes from insertion of the cystoscope or ureteroscope to completion of the definitive flexible ureteroscopy/retrograde intrarenal surgery procedure. Mean or median operative time will be compared between the JJ ureteral stent drainage group and the percutaneous nephrostomy drainage group. |
| Need for Ureteral Stenting After Definitive RIRS | At the end of the definitive RIRS procedure | The need for postoperative ureteral stent placement after definitive flexible ureteroscopy/retrograde intrarenal surgery will be recorded. The proportion of participants requiring postoperative stenting will be compared between both drainage groups |
| Intraoperative Complications During Definitive RIRS | During the definitive RIRS procedure | Intraoperative complications will include ureteral mucosal injury, false passage, ureteral perforation, bleeding affecting visualization, and procedure interruption. The incidence of intraoperative complications will be compared between both drainage groups. |
| Postoperative Infectious Complications After Definitive RIRS | From definitive RIRS to 4 weeks after definitive RIRS | Postoperative infectious complications will include fever greater than 38°C, systemic inflammatory response syndrome, or sepsis after definitive flexible ureteroscopy/retrograde intrarenal surgery. The incidence of postoperative infectious complications will be compared between both drainage groups. |
Countries
Egypt
Contacts
CONTACTHany F Badawy, MD
PRINCIPAL_INVESTIGATORHany F Badawy, MD
Faculty of medicine BeniSuef University
Outcome results
None listed