Treatment of renal transplant stones by extracorporeal shock-wave lithotripsy in the prone position

[Urinary lithiasis in renal transplant recipient]

OBJECTIVES

To report epidemiology and characteristics of urinary lithiasis and its management in kidney allograft at the time of organ procurement or after kidney transplantation.

MATERIAL AND METHODS

An exhaustive systematic review of the scientific literature was performed in the Medline database (http://www.ncbi.nlm.nih.gov) and Embase (http://www.embase.com) using different associations of the following keywords (MESH): urinary lithiasis, stone, kidney transplantation. Publications obtained were selected based on methodology, language, date of publication (last 10 years) and relevance. Prospective and retrospective studies, in English or French, review articles; meta-analysis and guidelines were selected and analyzed. This search found 58 articles. After reading, 37 were included in the text based on their relevance.

RESULTS

Frequency of urinary lithiasis in renal transplant recipient is similar to those observed in the general population. Generally, urinary lithiasis of the graft is asymptomatic because of renal denervation after organ procurement and transplantation. Nevertheless, this situation may be at high risk due to the immunosuppressed state of the recipient with a unique functioning kidney. Most of the time, the diagnosis is incidental during routine post-transplantation follow-up. Management of urolithiasis in renal transplant recipient is similar to that performed in general population.

CONCLUSION

Due to its potential severity in transplanted immunosuppressed patients with a sole kidney, urolithiasis requires expert urological management.

Ex vivo pyelotomy, nephroscopy and holmium laser lithotripsy of a staghorn stone in a donor kidney prior to renal transplant

This case report presents the diagnostic and treatment procedures of stone removal from the kidney of a 67-year-old donor, the transplantation of the kidney to a 65-year-old recipient, and the postoperative course until the end of hospitalization. Computed tomography performed before collecting the organ showed a staghorn stone in the renal pelvis and lower calyces in the right donor kidney. The stones were removed ex-vivo using a rigid ureteroscope and a holmium laser prior to transplantation. Then the organ was transplanted to the left iliac fossa of a 65-year-old man with end-stage renal failure. The authors think there is a possibility of increasing the kidney pool, by using organs containing large calculi. In such cases stones should be removed before the operation and the patient should be monitored regularly, especially in the first months after the transplant.

Haematuria in postrenal transplant patients

Haematuria has a prevalence of 12% in the postrenal transplant patient population. It heralds potentially dangerous causes which could threaten graft loss. It is important to consider causes in light of the unique, urological, and immunological standpoints of these patients. We review the literature on common causes of haematuria in postrenal transplant patients and suggest the salient approach to the evaluation of this condition. A major cause of haematuria is urinary tract infections. There should be a higher index of suspicion for mycobacterial, fungal, and viral infection in this group of immunosuppressed patients. Measures recommended in the prevention of urinary tract infections include early removal of foreign bodies as well as prophylactic antibiotics during the early transplant phase. Another common cause of haematuria is that of malignancies, in particular, renal cell carcinomas. When surgically managing cancer in the setting of a renal transplant, one has to be mindful of the limited retropubic space and the need to protect the anastomoses. Other causes include graft rejections, recurrences of primary disease, and calculus formation. It is important to perform a comprehensive evaluation with the aid of an experienced multidisciplinary transplant team.

Decrease in and management of urolithiasis after kidney transplantation

PURPOSE

Urolithiasis after kidney transplantation can involve several contributing factors and the treatment strategy is open to question. We determined the incidence and management of urolithiasis in kidney recipients.

MATERIALS AND METHODS

We retrospectively reviewed a single center series of 3,000 kidney graft recipients during 32 years to identify those with urolithiasis. We analyzed data by the prevalence per decade, including perioperative procedures (preoperative assessment, anastomosis type and urinary drainage) and long-term followup (urinary stenosis, time to presentation, size, site, treatment type, renal function and survival).

RESULTS

We identified 31 cases and noted a significant decrease in incidence from 2.1% to 0.6% during the 3 decades. Excluding 4 cases of donor in situ stones the mean time to diagnosis was 8.5 years. Surgical risk factors were ureteral obstruction in 41% of cases, infravesical obstruction in 14% and urinary-digestive anastomosis in 14%. A total of 12 cases (38%) were observed exclusively with 2 of spontaneous passage. With minor adaptations all mini-invasive procedures, including extracorporeal shock wave lithotripsy, endoscopy and percutaneous nephrolithotomy, were feasible in graft recipients. Antegrade procedures were facilitated by the ventral position of the graft. Eight patients (25%) were treated with open surgical ureteroureteral anastomosis.

CONCLUSIONS

Prevention with a perioperative Double-J® stent and early treatment of ureteral obstruction have decreased and stabilized the urolithiasis rate at around 0.6%. Careful surveillance or any currently available instrumental treatments of urinary stones can be valid options.

Renal transplant lithiasis: analysis of our series and review of the literature

BACKGROUND AND PURPOSE

Renal transplant lithiasis represents a rather uncommon complication. Even rare, it can result in significant morbidity and a devastating loss of renal function if obstruction occurs. We present our experience with graft lithiasis in our series of renal transplantations and review the literature regarding the epidemiology, pathophysiology, and current therapeutic strategies in the management of renal transplant lithiasis.

PATIENTS AND METHODS

In a retrospective analysis of a consecutive series of 1525 renal transplantations that were performed between January 1983 and March 2007, 7 patients were found to have allograft lithiasis. In five cases, the calculi were localized in the renal unit, and in two cases, in the ureter. A review in the English language was also performed of the Medline and PubMed databases using the keywords renal transplant lithiasis, donor-gifted lithiasis, and urological complications after kidney transplantation. Several retrospective studies regarding the incidence, etiology, as well as predisposing factors for graft lithiasis were reviewed. Data regarding the current therapeutic strategies for graft lithiasis were also evaluated, and outcomes were compared with the results of our series.

RESULTS

Most studies report a renal transplant lithiasis incidence of 0.4% to 1%. In our series, incidence of graft lithiasis was 0.46% (n=7). Of the seven patients, three were treated via percutaneous nephrolithotripsy (PCNL); in three patients, shockwave lithotripsy (SWL) was performed; and in a single case, spontaneous passage of a urinary calculus was observed. All patients are currently stone free but still remain under close urologic surveillance.

CONCLUSION

Renal transplant lithiasis requires vigilance, a high index of suspicion, prompt recognition, and management. Treatment protocols should mimic those for solitary kidneys. Minimally invasive techniques are available to remove graft calculi. Long-term follow-up is essential to determine the outcome, as well as to prevent recurrence.

Endourological Management of Urolithiasis in Donor Kidneys prior to Renal Transplant

Background. We present our centres successful endourological methodology of ex vivo ureteroscopy (EVFUS) in the management of these kidneys prior to renal transplantation. Patient and Methods. A retrospective analysis was performed of all living donors (n = 157) identified to have asymptomatic incidental renal calculi from January 2004 until December 2008. The incidence of asymptomatic renal calculi was 3.2% (n = 5). Donors were subdivided into 2 groups depending on whether theydonated the kidney with the renal calculus (Group 1) versus the opposite calculus-free kidney (Group 2). Results. All donors in Group 1 underwent a left laparoscopic donor nephrectomy. The calculi were extracted in all 3 cases using a 7.5 Fr flexible ureteroscope either prior to transplant (n = 2) or on revascularization (n = 1). There were no urological complications in either group. At a mean followup at 64 months there was no recurrent calculi formation in the recipient in Group 1. However, 1 recipient formed a calculus in group 2 at a follow up of 72 months. Conclusions. Renal calculi can be successfully retrieved during living-related transplantation at the time of transplant itself using EVUS. This is technically feasible and is associated with no compromise in ureteral integrity or renal allograft function.

Extracorporeal shockwave lithotripsy of ureteral stone in a patient with en bloc kidney transplantation: a case report

We report a case of ureterolithiasis in a patient with an en bloc kidney transplantation, using extracorporeal shockwave lithotripsy (ESWL). The patient presented with asymptomatic macrohematuria. Computed tomography revealed a ureteral calculus just below the pyeloureteral junction with hydronephrosis of the medially positioned kidney. Took two sessions of ESWL were required for complete disintegration of the stone. At 3 years after successful treatment, the patient has an excellent functioning and stone-free graft.

Experience with marginal living related kidney donors: Are they becoming routine or are there still any doubts?

OBJECTIVES

To analyze donor and recipient outcome of grafts from marginal kidney donors (ie, elderly or suffering from some anomaly).

METHODS

We had 81 marginal donors from July 1996 to July 2004; 46 were older than 60 years, and 39 had renal or nonrenal anomaly. The donors and recipients were evaluated for morbidity, graft and recipient survival, and the number of rejection episodes.

RESULTS

The mean (+/- standard deviation) age of elderly donors was 62.2 +/- 3.1 years. Follow-up ranged from 6 months to 50 months (mean 21.15 +/- 0.9 months). Actuarial 1-year and 3-year graft survival rates were 95% and 81%, respectively. Twenty-six percent of recipients maintained serum creatinine levels less than 1.4 mg/dL. The mean age of hypertensive donors was 46.2 years, and blood pressure was controlled with one drug. Serum creatinine levels in the recipients were less than 1.4 mg/dL in 10 and less than 2.5 mg/dL in the rest. Eleven percent of hypertensive donors required an increase in their antihypertensive medication. All donors showed a 15% to 20% increase in their glomerular filtration rate. Donors underwent simultaneous surgery when indicated.

CONCLUSIONS

Criteria to reject donors need to be reviewed periodically. The elderly and donors with other anomalies are consistently showing acceptable results. Hypertensive donors require assessment with awake ambulatory blood pressure monitoring.

Stone-bearing live-donor kidneys for transplantation

OBJECTIVE

To evaluate potential donor kidneys with asymptomatic calculi detected during screening, and the management of the calculus before, during and after transplantation, as with fewer live donors, marginal kidneys and donors are a significant subgroup in renal transplantation.

PATIENTS AND METHODS

Five live-related donors, with one incidentally detected calculus during their routine evaluation, were accepted for transplantation. Of these, three were detected only on spiral computed angiography. There was no biochemical evidence of a metabolic abnormality or history of stone disease. One donor had elective lithotripsy and another nephrolithotomy under ultrasonographic control immediately after perfusion. The others were transplanted with the calculus in situ. Ureteric reimplantation was by the Leadbetter-Politano technique over a JJ stent.

RESULTS

One recipient patient passed the calculus within 4 h of stent removal. The follow-up ultrasonogram at 3 months showed a stone in only one recipient. In the others, the calculus could not be seen after stent removal. The maximum follow-up was 2 years and graft function has remained normal in all.

CONCLUSIONS

Voluntary kidney donors with one calculus incidentally detected on routine evaluation form a unique group and can be accepted for transplantation in selected cases. Careful follow-up of the donor and recipient is essential, with early intervention if necessary.

Stone disease in kidney transplantation

The aim of this study was to evaluate etiologic, diagnostic, and management aspects of stone disease in renal transplant recipients and donors. Calculi from five patients were analyzed. The immunosuppressive regimen included tacrolimus or cyclosporine, mycophenolate mofetil, and corticosteroids in all cases. The etiology of the stone disease was cadaveric donor-gifted in one patient and de novo stone formation after transplantation in two patients. Additionally, stone disease was found and treated in living related donors in two patients. The mean follow-up was 32.4 +/- 19.7 months. In the living related donors, stones were initially treated by ESWL. Pyelotomy at the back table during the transplantation was required in one of them. The patient with cadaver-gifted stone was also treated by ESWL. In patients with de novo stone formation after transplantation, the stones were related to urinary infections and foreign body double-j (JJ) stent. A small stone in one of these patients (de novo formation) passed spontaneously after removal of the foreign body. Endoscopical lithotripsy was performed in the other patient. Stones are more frequently transplanted with allografts than expected; therefore, preoperative imaging of the donor is important. ESWL is recommended for medium-sized calculi in transplant kidneys. JJ stent insertion before ESWL might be needed in stones larger than 10 mm.

Ex Vivo Ureteroscopic Treatment of Calculi in Donor Kidneys at Renal Transplantation

PURPOSE

We evaluated the safety and efficacy of ex vivo ureteroscopy (ExURS) as a means of rendering the donated kidney stone-free at live donor renal transplantation.

MATERIALS AND METHODS

A total of 10 suitable kidney donors with small, unilateral nonobstructive calculi underwent live donor nephrectomy (8 open flank, 2 hand assisted transperitoneal). Immediately after cold perfusion, ExURS was performed in an iced saline solution. Access to the collecting system was via the ureteral stump. Calculi were either removed with endoscopic baskets and/or completely fragmented with Holmium laser lithotripsy.

RESULTS

Access to the renal collecting system was technically successful in all cases. A total of 10 stones, ranging in largest diameter from 1 to 8 mm (average 5.2) were visualized. Of the kidneys 6 had solitary stones, 2 had 2 stones and 1 had no stone. Of 10 stones 9 were successfully removed and/or fragmented with an average procedure time of 6.5 minutes (range 3 to 28). Indwelling ureteral stents were placed at transplantation in 5 of 10 kidneys. There were no intra-operative or postoperative ureteral complications. At 1 month after transplant serum creatinine ranged from 0.9 to 2.7 mg/dl (average 1.5). At a mean followup of 33.2 months new stones have not formed in any recipients and at mean 36.4-month followup no new calculi have formed in the remaining kidney of any donors.

CONCLUSIONS

ExURS is a technically feasible means of rendering a stone bearing kidney stone-free without compromising ureteral integrity or renal allograft function.

Urolithiasis in allograft kidneys

OBJECTIVES

Allograft stones are an uncommon clinical problem and management is mainly based on anecdotal experience, rather than analysis of larger series.

METHODS

In an 8-year period, 19 patients were treated for 19 renal and 3 ureteral stones. In 9 patients, stones were transplanted and 10 formed de novo stones within a mean of 28 months (range 13 to 48) after transplantation. In 4 patients, stones were removed during transplantation. Seven patients were treated with extracorporeal shock wave lithotripsy (ESWL), 3 patients had stones removed percutaneously, 1 by antegrade ureteroscopy, and 1 at the time of ureteral reimplantation. Three patients passed stones spontaneously.

RESULTS

In 3 of 4 patients with stones detected before transplantation, the procedure was completed successfully after endoscopic stone removal. Three of 5 patients with transplanted stones required emergency nephrostomy; 1 patient had permanent renal impairment. Three (42.9%) of 7 patients treated with ESWL needed transient nephrostomy; ultimately, all became stone free within a mean 15 days (range 10 to 40). Endoscopic stone removal always resulted in complete clearance without renal impairment. All patients were stone free during a follow-up of 29 months (range 13 to 48).

CONCLUSIONS

Nine (47%) of 19 stones were actually transplanted. Therefore, intraoperative screening by ultrasonography with subsequent endoscopic removal is advisable. Small stones (4 mm or less) may be closely followed up, because they can pass spontaneously. ESWL is the treatment of choice for caliceal stones sized 5 to 15 mm. However, for stones greater than 15 mm or for ureteral stones, antegrade endoscopic procedures seem to be more favorable.

Donor-gifted allograft urolithiasis: early percutaneous management

OBJECTIVES

To describe our successful early management of donor-gifted nephrolithiasis by percutaneous nephrolithotomy. Donor-gifted nephrolithiasis is a rare and frustrating complication of renal transplantation. In the past, initial conservative management with relief of obstruction and shock wave lithotripsy has been recommended.

METHODS

We treated 3 cases of donor-gifted cadaveric kidney transplant stones by a percutaneous approach 1 to 2 months postoperatively. Two patients presented with hydronephrosis-associated renal deterioration and febrile urinary tract infection, and the third was diagnosed incidentally on routine postoperative ultrasonography.

RESULTS

Percutaneous nephrolithotomy was performed with ultrasound stone fragmentation after initial nephrostomy tube drainage in 1 patient. In the second patient, the stone was successfully removed in a basket in an antegrade fashion. The third patient's ureteral stone was successfully removed by antegrade ureteroscopy. Postoperatively, no residual stones were noted on nephrostography, and renal function returned to normal. CONCLUSIONS. Post-transplant renal calculi can be managed successfully by percutaneous techniques in the early postoperative period and renal function can be salvaged. Pretransplant renal sonography may be considered to limit donor-gifted calculi.

[Incidence and treatment of urinary lithiasis in renal transplantation]

INTRODUCTION

Urinary calculi is an uncommon complication in kidney transplantation; several stone risk factors are found in transplanted patients, but in most cases there is not a relationship between these risk factors and stone formation. The treatment of these patients is complex due to their both immunosuppressive status and border-line renal function.

MATERIAL AND METHOD

From 1980 to February 2000, 1198 kidney transplant have been performed in our institution. We describe our series consisting in 22 urinary calculi (15 in the graft, 3 in the urether and 4 in the bladder) in 18 patients, including 7 stones detected in cadaveric donor patients.

RESULTS

We performed external shock wave lithotripsy in 7 patients, bench surgery in 4, endoscopic mechanic lithotripsy in 5, open surgery in 1 and observation in 6. Calcium oxalate (mono and dihidrate) was found in 9 of 13 calculi. Metabolic changes were found in 15 of the 18 patients, the most common was hiperuricemia. There were not complications of every treatment applied and 9% of them needed a savage treatment. We found recurrence in 4 cases (22.2%). Now 12 of the patients are stone-free (66.7%) and three have non-significative stones (83.3% without symptoms).

CONCLUSIONS

Detection of renal calculi in cadaveric renal donors is not a reason to refuse the graft for further transplantation. In both renal calculi up to 2 cm and uretheric calculi surgical treatment is assessed as first option. In caliceal stones smaller than 5 mm observations is the best treatment.

Renal transplant complications. Minimally invasive management

Advancements in endourology, laparoscopic urology, and interventional radiology continue to influence the contemporary management of renal transplant complications. The successful implementation of these minimally invasive therapies significantly relies on careful patient selection; not all renal transplantation complications are suitable or amenable for this form of management--true for transplant ureteral complications and less so for other potential complications. With such a strategy, renal transplant complications can be managed efficiently and effectively with these minimally invasive modalities to minimize further recipient morbidity while also minimizing potential risk to the recipient and for the renal allograft.

Urolithiasis in renal and combined pancreas/renal transplant recipients

PURPOSE

Urological complications in renal transplant recipients will become more common with increasing numbers of transplantations as well as increased graft survival secondary to improvements in immunosuppression. Urinary stone disease may be one of those complications. We determine the current incidence of urinary stone disease in renal transplant patients based on contemporary immunosuppressive regimens.

MATERIALS AND METHODS

We reviewed the records of 1,730 renal and 83 pancreas/renal transplantations performed during the cyclosporine era and identified 8 recipients (0.4%) with urinary stone disease, including 3 with renal pelvic stones, 1 with multiple ureteral stones and 4 with bladder calculi.

RESULTS

Treatment ranged from conservative observation to open pyelolithotomy, and included percutaneous nephrolithotomy and extracorporeal shock wave lithotripsy. The ureteral stones were removed with antegrade and retrograde ureteroscopy. The 4 bladder stones were treated with cystolithalopaxy. No case had significant permanent graft damage. Mean followup was 68.6 months. Mean serum creatinine was 1.5 mg./dl. (normal 0.5 to 1.3) at baseline and 2.38 after followup.

CONCLUSIONS

While the incidence of upper tract urinary stone disease in renal (0.23%) and pancreas/renal (1.2%) transplant recipients is not statistically significant (p <0.45), the latter have significantly higher rates of bladder stones (4.8 versus 0%, p <0.001). The diagnosis of urinary stone disease in transplant recipients can be challenging because of the lack of symptoms but the treatment approach is the same as in the normal population.

Ureteroscopic evaluation in renal transplant recipients

Percutaneous access and antegrade intervention have been the gold standard for the management of renal and ureteral complications in the renal transplant patient. We reviewed 540 consecutive renal allografts performed between July 1991 and September 1996 to determine the feasibility and morbidity of diagnostic and therapeutic ureteroscopy in renal allograft ureters. Of these, 14 patients (2.5%) had indications for endoscopic intervention of the allograft ureter. Four patients had obstructive ureteral calculi, three had migrated double-pigtail stents, three had persistent suspicious urinary cytology findings necessitating diagnostic ureteroscopy, three had persistent funguria, and one had multiple ureteral filling defects seen on retrograde ureteropyelography. Ureteropyeloscopy was successful in 93% of the patients. A diagnosis was made in all cases, including the one unsuccessful ureteroscopy, as this patient had allograft ureteral necrosis preventing passage of the endoscope into the renal pelvis. All of the migrated stents could be seen, and all but one was retrieved. Two of the patients with persistent funguria did have renal fungal balls, which were removed endoscopically, and the other case yielded a urothelial biopsy positive for fungus. All of the ureteral calculi were removed endoscopically. The only complication was ureteral perforation, which occurred in the patient with ureteral necrosis. Transplant ureteral endoscopy is a technically challenging intervention, but both diagnostic and therapeutic ureteroscopy can be performed with acceptable outcomes and minimal morbidity. One should consider ureteroscopy as an alternative to percutaneous and antegrade modalities, as these methods carry significant morbidity.

Update on interventional uroradiology

From its humble beginnings as a method of expediently decompressing the obstructed kidney, the field of interventional uroradiology has evolved in the hands of urologists and interventional radiologists to a means of addressing myriad problems in the urinary tract and has changed the day-to-day practice of urology. The foundation of interventional uroradiology is the creation of an appropriate entry into the urinary system. After a review of this basic procedure, extensions of the technique and new applications of emerging technology are reviewed.

Infection-induced stone formation in a renal allograft

Stone formation is an uncommon complication in renal allograft recipients. We report a 61-year-old woman who had undergone cadaveric renal transplantation in 1982 because of chronic renal failure due to polycystic kidney disease. Since 1985 she has developed recurrent urinary tract infections with Proteus mirabilis, and persistent microhematuria was detectable from 1988 on. Since renal function remained stable, she was repeatedly treated with antibiotics. Following a septicemia with P mirabilis, a staghorn calculus was discovered and was surgically removed from the allograft. Stone analysis (infrared spectrometry) revealed 60% struvite and 40% carbonate apatite. Since urinary tract infections with urea-splitting bacteria are a more frequent cause of stone formation in transplant patients than in nontransplant patients with kidney stones, stone disease should be considered in every allograft recipient presenting with recurrent urinary tract infection and microhematuria.