|Year : 2022 | Volume
| Issue : 4 | Page : 366-370
Ex vivo renal bench pyelolithotomy for renal calculi in live related kidney transplant: A prospective observational study
Ashish Sharma, Nripesh Sadasukhi, Sandeep Malik, TC Sadasukhi, HL Gupta, Manish Gupta
Department of Urology and Renal Transplant, Mahatma Gandhi Medical College, Jaipur, Rajasthan, India
|Date of Submission||10-Feb-2021|
|Date of Acceptance||31-Dec-2021|
|Date of Web Publication||30-Dec-2022|
Dr. Ashish Sharma
Department of Urology and Renal Transplant, Mahatma Gandhi Medical College, Jaipur, Rajasthan
Source of Support: None, Conflict of Interest: None
Background and Objectives: Bench surgery performed just after donor nephrectomy is known as ex vivo Bench Surgery. We present a case series of Bench Pyelolithotomy in donor's kidney just before transplantation with our surgical experience and follow-up results. Patients and Methods: Fifteen ex vivo Bench Pyelolithotomy on renal graft was performed by an experienced surgeon from January 2018 to August 2020. All these patients underwent standard donor evaluation and metabolic workup. Pre- and post-operative parameters were analyzed for technical feasibility, intraoperative and postoperative complications, stone clearance, and stone recurrence rate. Results: All 15 donors were females with a mean age of 44 years. The mean stone size was 14.3 mm (range 5–30 mm). Stone extraction by pyelolithotomy on the bench was successfully performed, and a stone-free status was accomplished just before the transplantation. Complete stone clearance was achieved in all cases. Mean cold ischemia time was 32 min. Postoperatively, patients were stable with average urine output of 490 ml/h. All patients are in regular follow-up with graft functioning well measured with respect to serial serum creatinine and urine output. Conclusions: Bench surgery is safe, less time-consuming, and equally effective for a stone-bearing renal donor kidney without compromising renal allograft function.
Keywords: Bench pyelolithotomy, donor nephrectomy, renal transplant
|How to cite this article:|
Sharma A, Sadasukhi N, Malik S, Sadasukhi T C, Gupta H L, Gupta M. Ex vivo renal bench pyelolithotomy for renal calculi in live related kidney transplant: A prospective observational study. Indian J Transplant 2022;16:366-70
|How to cite this URL:|
Sharma A, Sadasukhi N, Malik S, Sadasukhi T C, Gupta H L, Gupta M. Ex vivo renal bench pyelolithotomy for renal calculi in live related kidney transplant: A prospective observational study. Indian J Transplant [serial online] 2022 [cited 2023 Feb 2];16:366-70. Available from: https://www.ijtonline.in/text.asp?2022/16/4/366/364607
| Introduction|| |
Renal transplant is the best modality to treat end-stage renal disease (ESRD) patients. For the best results of renal transplant surgery, proper donor selection is the most important step. Lithiasis is known to be relative contraindication, however, no consensus is yet made. Since hypercalcemia, hyperparathyroidism, and hypocitraturia are some metabolic factors that are known to cause recurrent stone formation, hence a donor with lithiasis with no metabolic risk factor for calculus formation or anomalous kidney anatomy can be safely considered for the transplant. Renal donors should not have hypercalciuria, hyperuricemia, metabolic acidosis, cystinuria, and hyperoxaluria.
Management of calculi depends on the stone burden, size, and position of calculi. These calculi can cause obstruction, sepsis, and nonfunctioning of graft. Studies have suggested for watchful waiting in calculi <4 mm and intervention for larger and obstructive calculus.,
Literature suggest that extracorporeal shock wave lithotripsy/retrograde intrarenal surgery/percutaneous nephrolithotomy surgery as an adjunct procedure for complete stone clearance before undergoing the transplant. Bench surgery is performed just after donor nephrectomy also known as ex vivo Bench Surgery. It is considered only by a few surgeons in view of lack of experience in open surgery and fear of graft function loss.,
We present a case series of ex vivo bench pyelolithotomy in donor's kidney just before transplantation with our surgical experience and follow-up results.
| Patients and Methods|| |
Fifteen live renal donors with renal calculi from January 2018 to August 2020 were considered for transplantation after bench pyelolithotomy. All the risks of bench surgery and lithiasis were explained to the patients and donors with proper informed consent.
Diethylenetriamine pentaacetate renal scan was assessed along with total glomerular filtration rate (GFR) and differential GFR. Contrast-enhanced computed tomography (CECT) and renal angiography were done for the assessment of anatomy and anomalies of renal artery and vein. CECT also helped in assessing stone burden and location of the stone and for planning technique of ex vivo bench pyelolithotomy [Figure 1].
|Figure 1: Contrast enhanced computed tomography kidney ureter bladder with computed tomography urography|
Click here to view
All these patients underwent standard donor evaluation and metabolic workup. We included the donors with urolithiasis without other metabolic abnormalities. All the renal donors were first-time stones former. We excluded recurrent stone former as a renal donor subject. Since hypercalcemia, hyperparathyroidism, and hypocitraturia are some metabolic factors that are known to cause stone formation, hence we did the standard metabolic evaluation for urolithiasis of renal donors including assessment of hypercalciuria, hyperuricemia, metabolic acidosis, cystinuria, and hyperoxaluria. These parameters are done for recurrent stone formation evaluation. Donor selection was based on standard terms of left kidney having long vein length and better functioning kidney to remain with the donor. Calculi in the right kidney with pelvicalyceal dilatation were confirmed by intravenous urography, X-ray kidney ureter bladder (KUB), and Ultrasonography KUB.
Donor nephrectomy was done with rib cutting flank incision. After donor nephrectomy, cold perfusion of the renal graft was done. Bench pyelolithotomy was done in thirteen cases, giving incision on the posterior aspect of the renal pelvis while extended pyelolithotomy was performed in two cases [Figure 2]. Pelvic calculi were delivered and remaining calculi from calyces were subsequently taken out with the help of stone holding forceps [Figure 3]. The pyelolithotomy incision was closed watertight with vicryl 3.0 suture [Figure 4]. We performed fluoroscopy in selected patients, where were multiple, large stone and we suspected incomplete stone clearance during bench surgery.
Average cold ischemia time was calculated. The renal transplant was done with right Gibson incision. Donor vessels were anastomosed to external iliac vessels in end to side manner. Donor ureter was anastomosed to the native bladder by Lich Gregoir's Technique over 5/20 Fr Double J stent (DJ Stent). After achieving proper hemostasis, single abdominal drain was placed near the ureterovesical anastomosis.
The abdominal drain was removed on the 5th postoperative day. Foley catheter was removed on the 7th postoperative day as usual and DJ stent was removed after 21 days in 11 patients. While in three patients DJ stent was kept for 45 days. We looked for postoperative parameters such as hematuria, urine outputs, and levels of serum creatinine. We assessed the intraoperative as well as the postoperative complications. We performed ultrasound abdomen for evaluating stone-free status in transplanted kidneys.
Patients discharge and follow-ups
All patients were discharged under the stable condition with no haematuria normal serum creatinine. All patients are in regular follow-up with graft functioning well measured with respect to serial serum creatinine and urine output.
Data are expressed as mean ± standard deviation. Statistical analysis used Student t test to asses group differences for continuous variable and statistical significance was defined as P < 0.05. The extracted data was tabulated, and Prism GraphPad software (v6) was used for comparative statistical analyses. We used unpaired t-tests for continuous variables, and Fisher's exact tests for categorical variables.
The patient consent has been taken for participation in the study and for publication of clinical details and images. Patients understand that the names and initials would not be published, and all standard protocols will be followed to conceal their identity.
The ethical clearance was obtained from MGUMST, Jaipur Ethics Committee on January' 1, 2021, with IRB number NO.MGMCH/IEC/JPR/2021/212. The study was performed according to the guidelines in Declaration of Helsinki.
| Results|| |
In this retrospective study, fifteen live renal donors with renal calculi were considered for transplantation after bench pyelolithotomy. All patients were regularly followed up and the mean long-term follow-up duration was 16.3 months (range 6–24 months).
All 15 donors were females with a mean age of 44 years. The mean stone size was 14.3 mm (range 5–30 mm). The left kidney was taken for transplantation 14 times and right for 1 time. Mean cold ischemia time was 32 min. Calculi were exclusively in lower calyx in 8 patients and exclusively in the pelvis in 4 patients. Only two patients had multiple calculi, involving the pelvis and lower calyx [Table 1]. There was no residual stone after bench surgery in any of our study subjects.
Overall, four patients required fluoroscopic confirmation for stone-free status. We faced intraoperative difficulty during ureteroneocystostomy in three patients due to the short ureter and suboptimal vascularity of the ureter segment. We prophylactically kept DJ stent for a prolonged duration (for 45 days) in these three patients. One patient developed urinoma formation which was drained percutaneously under ultrasonography (USG) guidance. This urinoma could be due to avascular necrosis of the distal part of the ureter or due to improper ureteroneocystostomy anastomosis in that individual patient.
Post-operatively haematuria was seen in 8 patients which got cleared subsequently in 3–4 days. The average urine output was found to be 490 ml/h [Table 2]. We followed up transplanted patients for stone-free status by ultrasound abdomen. All patients remained stone-free till recent follow-up except one, which developed single small calculus of size 4 mm × 4 mm. He was managed conservatively. All the renal grafts were well functioning till the last follow-up (mean 16.3 months) and were comparable to other normal donor kidney without stone.
| Discussion|| |
Donors with nephrolithiasis are usually not considered for transplantation because of the risk of complications such as recurrent calculi, sepsis, obstruction, and graft loss. So usually, nephrolithiasis is relatively contraindicated in kidney transplantation in both deceased and living donors. The recent developments in the field of endourological surgical techniques have enabled surgeon's to successfully perform minimally invasive stone surgeries with lower morbidity, which are highly effective approaches to overcome these risks. There is no standard guideline for the type of stone which should be considered for conservative management and which one should be considered for bench surgery. However, the stone <4 mm usually pass spontaneously in 76%–98% normal population but no data is available for the transplanted kidney., There are very few studies reporting the successful and effective use of donor's kidneys with nephrolithiasis in Renal Transplantations and still there is, no standards have been established yet for the treatment of nephrolithiasis in kidney donors.
A study of ex vivo bench ureteroscopy conducted on 15 renal donors with calculi of size 4–10 mm by Pushkar et al., reported the stone removal by Bench Pyelotomy after pushing the stone into pelvis. It was successfully achieved. Another case series by Ganpule et al. reported the successful removal of stone via a 12-Fr nephroscope introduced through pyelotomy incision. In a similar study, Sarier et al. successfully performed pyelolithotomy on 13 stone-bearing kidneys, under fluoroscopic guidance, and removed stones using stone forceps (by Randall kidney stone forceps, except for one patient). In this present case series, we successfully carried out 15 bench pyelolithotomy with the help of stone holding forceps.
It is well established from various studies that in living donor RT, cold ischemia time up to 8 h is acceptable, as it does not compromise the renal functions, increase acute rejection rates or affect long-term allograft survival. No study conducted on ex vivo bench surgery in the past, reports any renal damage related to the cold ischemic time or duration of the operation. However, still, it is well-understood fact that cold ischemic time should be as minimal as possible. In our study, the mean cold ischemia time was 32 min which is similar to studies conducted in the recent past.
In this study, one patient developed urinoma formation which was drained percutaneously under USG guidance. It could be due to avascular necrosis of the distal part of the ureter or due to improper ureteroneocystostomy anastomosis in that individual patient. We did drain the urinoma percutaneously under USG guidance. There was no residual stone in any patient and stone-free status was obtained.
Bench pyelotomy has its own disadvantages of postoperative urine leak because of high urine output hinders healing. ESRD patients are supposed to be slow wound healers. Increase in cold ischemia time is also a big concern. However, bench surgery has its own advantages of decreased waiting time for transplant and it is easy to handle kidneys on bench. Bench surgery is a simple and easy-to-learn procedure, for experienced surgeons who specialize in endourology. Thus, we believe that performing even one procedure is sufficient for a surgeon to develop adequate expertise. We performed 15 Bench Pyelolithotomy with no complication and good graft function on follow-up.
It is a single center study. Similar studies across multiple centers can validate the results.
| Conclusions|| |
In the present study, we performed 15 bench pyelolithotomy on donor's kidney just before transplantation. All grafts are healthy with no complications on regular follow-up. Bench surgery if done by experienced surgeon with proper planning is safe, less time-consuming, and equally effective for a stone-bearing renal donor kidney without compromising renal allograft function.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2]