Endourologic therapy of bladder calculi in simultaneous kidney-pancreas transplant recipients

Bladder Stones in Renal Transplant Patients: Presentation, Management, and Follow-up

INTRODUCTION

The study aim was to analyze the presentation, management, and follow-up of renal transplant patients developing bladder calculi.

METHODS

Patients who underwent renal transplant with postoperative follow-up at our institution were retrospectively analyzed (1984-2023) to assess for the development of posttransplant bladder stones. All bladder stones were identified by computerized tomography imaging and stone size was measured using this imaging modality.

RESULTS

The prevalence of bladder calculi post-renal transplantation during the study window was 0.22% (N = 20/8,835) with a median time to bladder stone diagnosis of 13 years posttransplant. Of all bladder stone patients, 6 (30%) received deceased donor and 14 (70%) living donor transplants. There were 11 patients with known bladder stone composition available; the most common being calcium oxalate (N = 6). Eleven (55%) patients had clinical signs or symptoms (most commonly microhematuria). Fourteen of the bladder stone cohort patients (70%) underwent treatment including cystolitholapaxy in 12 subjects. Of these 14 patients, 9 (64%) were found to have nonabsorbable suture used for their ureteroneocystostomy closure.

CONCLUSIONS

The prevalence of bladder stones post-renal transplant is low. The utilization of nonabsorbable suture for ureteral implantation was the main risk factor identified in our series. This technique is no longer used at our institution. Other factors contributing to bladder stone formation in this population warrant identification.

Radiographic features of suspected suture-associated cystic calculi in dogs

This retrospective case series describes the radiographic features of suspected suture-associated cystic calculi in six dogs with a history of at least one or multiple prior cystotomies. One of the dogs presented twice. Suspected suture-associated cystic calculi were multifocal, short, predominantly linear mineral opacities localized in the center of the urinary bladder on abdominal radiographs. One patient (n = 1) presented with multifocal round, pin point, and linear radiopaque calculi. The calculi were all calcium oxalate in composition. On gross examination, the calculi had a hollow center. Six cystotomies used monofilament absorbable suture material (polydioxanone [n = 4] or poliglecaprone 25 [n = 1]) in prior cystotomies. Suture material in two of the cases was unknown. Suspected suture-associated cystic calculi are a rare occurrence in veterinary medicine but should be considered in dogs that have a history of prior cystotomy, hollow core on gross analysis, and radiographic evidence of mineral opaque, predominantly linear, cystic calculi.

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.

Urological complications after simultaneous pancreas-kidney transplantation

OBJECTIVE

We evaluated the incidence of urological complications after simultaneous renal and pancreatic transplantation.

PATIENTS AND METHODS

We retrospectively reviewed urological complications following 107 simultaneous kidney-pancreas transplantations performed at our institution between March 1995 and June 2008. The 46 women and 61 men were of mean age 37.8 years (range, 25-66). The mean duration of diabetes mellitus was 23.0 years (range, 9-48) and the mean duration of dialysis was 19.9 months (range, 0-70). The exocrine pancreatic secretions were drained to bladder in 58 cases, or enterically in 49 patients. The mean length of follow-up was 51.7 months.

RESULTS

The most frequent urological complication was urinary tract infection, reported in 63.8% of patients: 42 bladder-drained and 25 enteric-drained (P = .011). Hematuria occurred in 13 patients (12.5%): 12 bladder-drained and 1 enteric-drained (P = .002). Five bladder-drained patients developed bladder calculi. Among 58 bladder-drained patients, reflux pancreatitis occurred in 28 patients and urine leaks related to the pancreatic graft occurred in 7 patients. Conversion of exocrine secretions from bladder to enteric diversion was required in 6 patients. One- and 3-year patient survival rates were 92.7% and 89.1%, respectively. Moreover, 1 and 3-year kidney graft survival rates were 90.6% and 84.4%, and pancreas graft survival rates were 78.1 and 70.3%, respectively.

CONCLUSION

Simultaneous kidney-pancreas transplantation with bladder drainage is associated with a high frequency of urological complications. Appropriate treatment can resolve most complications. In our opinion, both enteric and bladder drainage seemed to be safe and effective alternatives to manage pancreatic exocrine secretions.

Endourologic management of duodenal calculi in pancreas-kidney transplantation

Duodenal stones formed during pancreas-kidney transplantation are usually associated with nonabsorbable sutures or staples. We report on the delayed formation of a struvite duodenal stone not attributed to foreign material, managed successfully with intracorporeal electrohydraulic lithotripsy.

Endoscopic treatment of bladder calculi in post-renal transplant patients: a 10-year experience

BACKGROUND AND PURPOSE

Urinary calculus formation following renal transplantation is an uncommon phenomenon. As a result of the growing number of renal transplants performed and the greater graft survival, there has been increased awareness of transplant-related complications, one of which is calculus formation. We report our experience in the management of bladder calculi after renal transplantation.

PATIENTS AND METHODS

We retrospectively reviewed the charts of 500 consecutive renal transplant patients from 1992 through 2002 and encountered 7 who had bladder calculi postoperatively. Ureteroneocystostomy had been performed using polyglactic acid suture. Bladder calculi were treated endoscopically by litholapaxy, electrohydraulic lithotripsy (EHL), or holmium:YAG laser lithotripsy.

RESULTS

Three calculi were found incidentally at the time of stent removal, and the others were associated with hematuria (43%), urinary tract infection (14%), or irritative voiding symptoms (14%). Eighty-six percent of the calculi were close to the allograft ureteral orifice.

CONCLUSION

While various forms of lithotripsy were employed in treating bladder calculi, Hol:YAG laser lithotripsy appeared to be both efficacious and safe. Both EHL and litholapaxy were complicated by mucosal bleeding necessitating Bugbee fulguration. Holmium:YAG laser lithotripsy was not associated with mucosal bleeding, and fulguration was not required near the allograft ureteral orifice. In addition, ureteral stenting is not required. Bladder calculi may form over both absorbable and nonabsorbable suture material, and the ideal suture for the ureteroneocystostomy has yet to be found. Until then, the Hol:YAG laser should be the lithotrite of choice for bladder calculi following renal transplantation.

Urodynamic testing predicts long-term urological complications following simultaneous pancreas-kidney transplantation

INTRODUCTION

Combined pancreas-kidney transplantation is the treatment of choice for patients with type I diabetes mellitus associated with chronic renal failure. The introduction of the bladder drainage technique constituted a marked improvement of the surgical technique with a reduction of life-threatening complications. However, drainage of pancreatic secretions via the urinary bladder causes urological complications leading, in some cases, to cystoenteric conversion. We retrospectively analysed whether pre-operative urodynamic findings may predict the subsequent development of urological complications and influence the choice of exocrine secretion drainage.

PATIENTS AND METHODS

From 1987 to 1997, 39 bladder-drained simultaneous pancreas-kidney transplantations were performed in 16 men and 23 women with a mean age of 38.5 yr. All patients underwent a complete urological assessment prior to surgery, including medical history, physical examination, urethrocystography and urodynamic assessment.

RESULTS

Twenty-eight patients are alive with a mean follow-up of 62 +/- 8 months. In 60% of cases, both kidney and pancreas remain functional. Seven patients experienced recurrent lower urinary tract infections. Six patients suffered from chemical urethritis (four men and two women) and six suffered from recurrent haematuria (blood transfusions were required in two patients). One patient had incrusted stones at the site of duodenal staples. Urological complications were mostly observed in the 22 patients (79%) with abnormal urodynamic characteristics (Relative risk: 5.1). Intravenous Somatostatin failed to definitively cure these complications in most cases. Seven patients (17%) (five with urethritis, two with haematuria) required cystoenteric conversion. Two patients developed post-operative ileal fistula, one cutaneous and one into the bladder. All urinary symptoms resolved in these seven patients.

CONCLUSION

The frequency of specific urinary complications is high (28%) in bladder-drained simultaneous pancreas-kidney transplantation patients. These complications are statistically more frequent in the case of an abnormal pre-transplant urodynamic assessment.

The vesical calculus

Bladder calculi account for 5% of urinary calculi and usually occur because of foreign bodies, obstruction, or infection. Males with prostate disease or previous prostate surgery and women who undergo anti-incontinence surgery are at higher risk for developing bladder calculi. Patients with SCI with indwelling Foley catheters are at high risk for developing stones. There appears to be a significant association between bladder calculi and the formation of malignant bladder tumors in these patients. Transplant recipients are not at increased risk for developing vesical calculi in the absence of intravesical suture fragments and other foreign bodies. Patients who undergo bladder-augmentation procedures using a vascularized gastric patch appear to be protected from vesicolithiasis, perhaps by the acidic environment. Ileum and colon tissues, however, are colonized by urease-producing organisms, producing an alkaline pH that promotes stone formation. Children remain at high risk for bladder-stone development in endemic areas. Diet, voiding dysfunction, and uncorrected anatomic abnormalities, such as posterior urethral valves and vesicoureteral reflux, predispose them to bladder-calculus formation. Finally, there are a number of techniques and modalities available to remove bladder stones. Relieving obstruction, eliminating infection, meticulous surgical technique, and accurate diagnosis are essential in their treatment.