Utility of Pre-Transplant Bladder Cycling for Patients With a Defunctionalized Bladder. A Randomized Controlled Trial

OBJECTIVE

To study the necessity of pre-transplant programmed bladder cycling (PBC) in patients with defunctionalized bladder (DB).

METHOD

This RCT included renal transplant (RT) candidates with DB. Eligible patients were assigned to 2 groups, group I underwent PBC before RT and group II underwent direct RT into the DB. The primary outcome was to assess the efficacy of PBC in improving post- RT bladder capacity. Secondly, to compare its impact on early urological complications and 3-month voiding function and 1-year graft function and survival. Graft function was evaluated using serum creatinine and eGFR using MDRD equation.

RESULTS

Groups I included 23 patients and group II included 20 patients. The mean ±SD of bladder capacity was 88.7±11.7mL and 90.6 ±9.8mL in both groups, respectively (P = .5). In group I, PBC increased bladder capacity to 194.7 ±21.2 mL (P < .001). Targeted bladder capacity was achieved in 19 (82.6 %) patients and 2 patients developed UTI. At 3-months, bladder capacity, compliance and bladder contractility index improved significantly in both groups with a significant reduction in maximum detrusor pressure with no significant difference between both groups (P = .3,0.4, 0.2 and 0.8, respectively). Urinary leakage occurred in one (4.3%) and 3 patients (15%) in group 1 and 2, respectively (P = .2). At 1-year, no statistically significant differences in the median (IQR) serum creatinine (P = .05) and eGFR (P = .07) between both groups were noted.

CONCLUSION

Pre-transplant PBC for DB-patients provided no clinical advantage concerning post-operative urological complication, urodynamic criteria and graft function and survival.

Factors associated with low-compliance bladder in end-stage renal disease patients and development of a clinical prediction model for urodynamic evaluation: the DUDi score

OBJECTIVES

To investigate factors associated with low-compliance bladders (LCB) in pretransplant patients with end-stage renal disease (ESRD) and develop a clinical prediction model for urodynamic studies.

METHODS

This study was a prospective cohort study. Patients with ESRD on the renal transplantation waiting list were recruited and underwent the urodynamic study. Demographics data, predictor factors related to the bladder compliance such as underlying disease of the lower urinary tract disease (LUTD), duration of urine < 250 mL/day, type and duration of renal replacement therapy (RRT), urine volume per day and urodynamic study information were collected. Univariable and multivariable logistic regression models were used to assess the independence of explanatory factors, then we developed the clinical prediction model.

RESULTS

One hundred fifty-two patients participated in the study: 94 patients in the normal bladder group and 58 patients in LCB group. Demographic data were not significantly different between the two groups, except diabetes. Cystometric capacity, detrusor pressure, compliance were significantly different. From the univariate analysis, DM status, duration of RRT, and passing < 100 mL of urine per day were related to LCB. We named the prediction model, the DUDi score based on the predictors (Duration of RRT, Urine volume/day, Diabetes). Higher scores predicted a higher risk of low-compliance bladder [P value = 0.464 according to the Hosmer-Lemeshow test, and the AUC was 0.87 (95% CI 0.81-0.92)].

CONCLUSIONS

Our clinical prediction model is easy to use and provides a high predictive value that is appropriate for patients who have no known LUTD to identify low-compliance bladder. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION FOR PROSPECTIVELY REGISTERED TRIALS: This study was approved by the Thai Clinical Trials Registry Committee on 09 February 2021. The TCTR identification number is TCTR20210209006.

Spectrum of lower urinary tract symptoms after renal transplant among adult non-urologic anuric patients and their management in a tertiary care center

INTRODUCTION

Lower urinary tract symptoms (LUTS) in a post-transplant patient can lead to several complications including recurrent UTI and deterioration of the graft kidney function. The aim of this study is to investigate the spectrum of LUTS, possible complications resulting from it and its management after renal transplant in pre-transplant anuric patients operated in our tertiary care institute.

MATERIALS AND METHODS

It was a retro-prospective observational study done on post-transplant patients operated in this institute from December 2016 to December 2020. Among 165 patients operated during this period 50 male and 21 female patients were finally included in this study. Urinary symptoms were evaluated using the IPSS Questionnaire. Pre and post-surgery Uroflowmetry findings were compared. Urodynamic assessment was done at least 6 months after surgery to determine the cause behind such symptoms. The data was analyzed with the help of standard statistical methods and SPSS 21 software.

RESULTS

The most common LUTS among the post renal transplant patients were frequency and nocturia. There was a marked improvement in voided volume and urinary flow in most of the patients. In 11 male and 7 female patients LUTS symptoms were moderate to severe and were seldom associated with recurrent UTI and graft compromise. A cautious approach in these patients helped in early diagnosis of the etiology behind LUTS, which were treated accordingly.

CONCLUSION

LUTS should be carefully evaluated before renal transplantation. Postoperatively moderate to severe LUTS symptoms should be thoroughly investigated so that graft compromise and related complications can be prevented by early intervention.

Allograft Vesicoureteral Reflux after Kidney Transplantation

Allograft vesicoureteral reflux (VUR) is a leading urological complication of kidney transplantation. Despite the relatively high incidence, there is a lack of consensus regarding VUR risk factors, impact on renal function, and management. Dialysis vintage and atrophic bladder have been recognized as the most relevant recipient-related determinants of post-transplant VUR, whilst possible relationships with sex, age, and ureteral implantation technique remain debated. Clinical manifestations vary from an asymptomatic condition to persistent or recurrent urinary tract infections (UTIs). Voiding cystourethrography is widely accepted as the gold standard diagnostic modality, and the reflux is generally graded following the International Reflux Study Committee Scale. Long-term transplant outcomes of recipients with asymptomatic grade I-III VUR are yet to be clarified. On the contrary, available data suggest that symptomatic grade IV-V VUR may lead to progressive allograft dysfunction and premature transplant loss. Therapeutic options include watchful waiting, prolonged antibiotic suppression, sub-mucosal endoscopic injection of dextranomer/hyaluronic acid copolymer at the site of the ureteral anastomosis, and surgery. Indication for specific treatments depends on recipient’s characteristics (age, frailty, compliance with antibiotics), renal function (serum creatinine concentration < 2.5 vs. ≥ 2.5 mg/dL), severity of UTIs, and VUR grading (grade I-III vs. IV-V). Current evidence supporting surgical referral over more conservative strategies is weak. Therefore, a tailored approach should be preferred. Properly designed studies, with adequate sample size and follow-up, are warranted to clarify those unresolved issues.

[Lower urinary tract symptoms and urinary incontinence in renal transplant recipients and candidates: The French guidelines from CTAFU]

OBJECTIVE

To propose surgical recommendations for the management of lower urinary tract symptoms (LUTS) and urinary incontinence in kidney transplant recipients and candidates.

METHOD

Following a systematic approach, a review of the literature (Medline) was conducted by the CTAFU focusing on medical and surgical treatment of LUTS and urinary incontinence in kidney transplant recipients and candidates. References were assessed according to a predefined process to propose recommendations with levels of evidence.

RESULTS

Functional bladder capacity and bladder compliance are impaired during dialysis. LUTS, related to pre-kidney transplantion alterations, frequently improve spontaneously after kidney transplantation. LUTS secondary to benign prostatic hyperplasia (BPH) may be underestimated before kidney transplantation due to oliguria, low bladder compliance and low bladder capacity. In LUTS associated with BPH, anticholinergics require dosage adjustment with creatinine clearance. If surgery is indicated after kidney transplantation, procedure can be safely performed in the early post-transplant course after removal of ureteral stent. Surgical management of urinary incontinence does not seem to be associated with an icreased risk for infectious complications in kidney transplant recipients. Particular attention should be paid to the management of postvoid residual and bladder pressures in case of neurological bladder disease. Optimal care of neurological bladder should be provided prior to transplantation: with a cautious management, and despite an increased occurrence of febrile urinary tract infections, transplant survival is not compromised.

CONCLUSION

These recommendations must contribute to improve the management of lower urinary tract symptoms and urinary incontinence in kidney transplant patients and kidney transplant candidates.

Candidate genes involved in the defunctionalization and refunctionalization of the urinary bladder induced by bladder anuria and reperfusion

AIMS

We develop a novel rabbit urinary diversion model of bladder defunctionalization due to bladder anuria followed by refunctionalization due to urine reperfusion to investigate the molecular biological background. To validate the results, we used reverse transcription-polymerase chain reaction (RT-PCR) to analyze human specimens from defunctionalized bladders in patients receiving dialysis before kidney transplantation.

METHODS

Female rabbits were divided into three groups: control, defunctionalized, and refunctionalized. The bilateral ureters were anastomosed to vagina in the defunctionalized and refunctionalized groups at 0 weeks. In the refunctionalized group, the unilateral ureter was reanastomosed to the bladder at 8 weeks.

RESULTS

The capacity and compliance of the rabbit bladder in the refunctionalized group were significantly lower than those in the control group at 8 weeks and higher than those in the defunctionalized group at 14 weeks. The significant downregulation of IGFBP2, UPK1B, and CST6 in the defunctionalized group compared with that in the control groups, and the significant downregulation of AGTR2 in the refunctionalized group compared with that in the defunctionalized group in the rabbit bladder-muscle DNA microarray were validated by RT-PCR. Human bladder muscle indicated significant downregulation of UPK1B and CST6 and significant downregulation of IGFBP2 in the defunctionalized group, which is consistent with both rabbit bladder-muscle DNA microarray and rabbit bladder RT-PCR results.

CONCLUSIONS

The present study using novel model of bladder defunctionalization followed by refunctionalization indicated the consistent downregulation of UPK1B and CST6 in muscle and the consistent downregulation of IGFBP2 in mucosa in process of bladder defunctionalization, which was validated by human specimens.

Partial Cystectomy of Paraganglioma of the Urinary Bladder Before Living Kidney Transplantation: Case Report

BACKGROUND

Paraganglioma (extra-adrenal pheochromocytoma) of the bladder is a very rare disease, accounting for 0.06% of all bladder tumors. Optimal management of bladder paraganglioma before kidney transplantation is unknown. We report a case of partial cystectomy for urinary bladder paraganglioma before living kidney transplantation.

CASE PRESENTATION

A 59-year-old man with a 27-year history of hemodialysis was referred to our department for further examination of a bladder tumor detected during pre-transplantation testing. Cystoscopy revealed a submucosal tumor on the right side of the bladder. The patient experienced a hypertensive crisis during transurethral resection of the bladder tumor. Endocrinologic and pathologic examinations confirmed the diagnosis of paraganglioma in the urinary bladder. A partial cystectomy was performed before kidney transplantation. Nine months after partial cystectomy, the patient underwent AB0-incompatible living kidney transplantation from his spouse. No disease recurrence or graft rejection was observed 12 months after the transplantation.

CONCLUSIONS

To our knowledge, this is the 1st report on the management of paraganglioma in the urinary bladder before living kidney transplantation. Kidney transplantation after partial cystectomy is an option that may be considered in patients with paraganglioma of the urinary bladder, with careful observations of bladder function and vesicoureteral reflux to the grafts.

Pretransplant defunctionalized bladder-overrated condition?

AIMS

The objective of this study was to evaluate the expression of bladder receptors in patients with defunctionalized bladder (DB) and to assess voiding behavior after refunctionalization.

METHODS

A total of 68 pretransplant patients were divided in two groups: DB (diuresis <300 mL/24 h; n = 33) and NDB (non-DB; diuresis ≥300 mL/24 h; n = 35). A sample of mucosa and detrusor at the site of the future ureteral implantation was collected. The following receptors were assessed by real-time polymerase chain reaction (qRT-PCR): M₂ , M₃ , α_1D , β₃ , P2X₂ , P2X₃ , TRPV1, TRPV4, TRPA1, and TRPM8. At 3, 6, and 12 months after transplant patients answered IPSS and ICIQ-OAB questionnaires and filled a 3-day 24 h frequency/volume chart (FVC) at 6 and 12 months.

RESULTS

The expression of all receptors in the mucosa and in the detrusor was similar in both groups, except from α_1D , which was overexpressed in the detrusor of DB relatively to NDB group. ICIQ-OAB symptom score was similar between the groups at 3, 6, and 12 months. There was a reduction of this score in both groups with time. The same pattern was found for IPSS score. Bother scores were similar between groups. No difference was observed for all FVC parameters between DB and NDB patients.

CONCLUSION

Gene expression of bladder receptors involved in micturition control was similar in patients with or without DB. Bladder behavior had a similar pattern independently of pretransplant residual diuresis. These findings question the relevance of the term DB in pretransplant patients.