A series of unfortunate bladder events: An illustrative case series of a diverse cohort of bladder perforations.

Bladder perforation is a potentially life-threatening condition, typically occurring after genitourinary trauma. The vast majority of cases are secondary to blunt abdominal trauma resulting in pelvic fractures, with motor vehicle accidents the commonest cause. There are however a wide range of underlying causes, including iatrogenic injuries and spontaneous perforations. This case series of 4 unusual cases of bladder perforations presenting to a single center under the same consultant within a 3-month period aims to highlight the diverse nature of patients who can present with bladder perforations and the different management options available.

Predictors of Stone-Related Events in Asymptomatic Untreated Intrarenal Calculi.

Purpose: There is a lack of data on the natural history of asymptomatic intrarenal calculi. In this study, we investigate stone-related events (SREs) in patients with untreated intrarenal calculi. We also investigate predictive factors for SREs. Methods: All patients found with an asymptomatic intrarenal calculus on CT kidney, ureter, bladder managed conservatively with interval imaging for ≥6 months were included. Patients were evaluated for any SRE. The rate of event according to calculus size, location, and number of calculi was also analyzed. Multivariate logistic regression analysis was performed to determine significant predictors for SREs. Results: In total, 266 renal units from 177 patients met inclusion criteria. The mean stone size was 4.44 mm (range 1-25 mm). Duration of follow-up was 43.78 ± 26.86 months (range 6-106 months). The overall rate of SREs, including intervention (n = 80) and spontaneous stone passage after ureteral colic (n = 40), was 45.1% (n = 120/266). Stones >5 mm were more likely to lead to an event compared with stones ≤5 mm (odds ratio [OR]: 2.94; p = 0.01). Interpolar stones and stones located in multiple calices were more likely to cause a SRE than lower pole stones (OR: 2.05; p = 0.05 and OR: 2.29; p = 0.03, respectively). Conclusion: In this large series of patients with asymptomatic intrarenal calculi, the incidence of a spontaneous SRE was 45.1% after 41 months. Stone size and stone location were significant predictors for a SRE. Information from this study will enable urologists to accurately risk stratify patients with asymptomatic renal stones.

A gender comparison of postobstructive injury in the rat kidney.

BACKGROUND/AIMS: Unilateral ureteral obstruction (UUO) results in renal injury. Studies report increased injury indices in male rats following UUO. Our study examined whether this gender-based renal response to UUO was reflected in sustained differences following relief of obstruction. METHODS: Adult male/female rats (200-400 g) were subjected to either sham surgery (S/RN) or UUO (UUO/RN). At 24 h, obstruction was relieved and all animals underwent contralateral nephrectomy. Five days after initial surgery, animals were placed in metabolic cages and given water ad libitum for 24 h followed by a 24-hour period of complete water restriction. On day 7, animals were euthanized and samples harvested. Tubular injury, urinary volume/osmolality, creatinine clearance, plasma arginine vasopressin, renal medullary V2 receptor and aquaporin 2 (AQP2) expression were measured. RESULTS: Male UUO/RN rats showed increased renal apoptotic injury and reduced creatinine clearance rates (glomerular filtration rate) vs. females. No gender-dependent differences were observed in urinary osmolality or concentrating ability. AQP2 expression increased post-obstruction. CONCLUSION: Increased injury in males following UUO remains manifest during early recovery after release of obstruction. Despite this, the grade of postobstructive diuresis is not significantly altered between sexes. This may reflect reduced glomerular filtration rate and elevated AQP2 in male rats.

Antegrade and Retrograde Endoscopic Approaches for Managing Obstructing Ureteral Calculi in Renal Transplant Patients: An Illustrative Case Series.

Purpose: To demonstrate the various antegrade and retrograde endourologic approaches that may be required for effectively treating kidney transplant recipients presenting with ureteral obstruction caused by urolithiasis. Materials and Methods: We prospectively evaluated endoscopic management techniques of renal transplant recipients referred to a national kidney transplant center with obstructing transplant ureteral calculi for a 12-month period (April 2019-April 2020). Results: Four kidney transplant recipients presented with ureteral obstruction caused by urolithiasis and the mean age was 66.6 (range: 62-71) years. The mean duration from renal transplantation was 16 (range: 6-25) years. Three patients presented with acute urosepsis and one patient presented with malaise and recurrent urinary tract infections. Two patients were definitively treated with percutaneous antegrade flexible ureteroscopic lithotripsy through a 16F minipercutaneous nephrolithotomy sheath. Two patients were definitively treated with retrograde flexible ureteroscopy (7F single-use disposable ureteroscope) and laser lithotripsy. Full stone clearance was achieved in all four patients and no perioperative complications occurred. Conclusion: Management of ureteral calculi in renal transplant recipients is challenging. A multimodal approach involving antegrade and retrograde endoscopic techniques may be required to achieve full stone clearance.

Increased E-cadherin expression in the ligated kidney following unilateral ureteric obstruction.

E-cadherin expression in the kidney is used as a surrogate marker of epithelial mesenchymal transition for the testing of various antifibrotic strategies. Here we reexamined E-cadherin expression in the kidneys of rats with unilateral ureteric obstruction, which was previously reported to decrease in parallel with the development of tubulointerstitial disease in this widely used experimental model of renal fibrosis and epithelial mesenchymal transition. E-cadherin mRNA expression was consistently increased both acutely (hours) and chronically (days) in the ligated kidney compared to the cognate non-ligated kidney. Increased E-cadherin protein levels were also found in the ligated kidney particularly in dilated tubular segments. Simulation of early pressure changes in the ligated kidney by mechanical stretch of human renal epithelial cells in culture did not alter E-cadherin expression. Porcine LLCPK-1 cells subjected to hypotonic stretch, however, did have increased E-cadherin mRNA and protein levels, responses that were not prevented by transforming growth factor-beta, a cytokine that promotes epithelial mesenchymal transition. Our findings question the utility of E-cadherin as a marker of epithelial mesenchymal transition in this model of renal fibrosis.

The management of rectal bleeding following transrectal prostate biopsy: A review of the current literature.

INTRODUCTION: Since the advent of prostate-specific antigen (PSA)-based testing, transrectal ultrasound (TRUS)-guided prostate biopsy has become a standard part of the diagnostic pathway for prostate cancer (PCa). Rectal bleeding is one of the common side effects of this transrectal route. While rectal bleeding is usually mild and self-limiting, it can be life-threatening. In this article, we examine rectal bleeding post-TRUS-guided prostate biopsy and explore the literature to evaluate techniques and strategies aimed at preventing and managing this common and important complication. METHODS: A PubMed literature search was carried out using the keywords "transrectal-prostate-biopsy-bleed." A search of the bibliography of reviewed studies was also conducted. Additionally, papers in non-PubMed-listed journals of which the authors were aware were appraised. RESULTS: Numerous modifiable risk factors for this bleeding complication exist, particularly anticoagulants/antiplatelets and the number of core biopsies taken. Successfully described corrective measures for such rectal bleeding include tamponade (digital/packs/catheter/tampon/condom), endoscopic sclerotherapy/banding/clipping, radiological embolization, and surgical intervention. CONCLUSIONS: We advocate early consultation with the colorectal/gastroenterology and interventional radiology services and a progressive, stepwise approach to the management of post-biopsy rectal bleeding, starting with resuscitation and conservative tamponade measures, moving to endoscopic hemostasis ± radiological embolization ± transanal surgical methods. Given the infrequent but serious nature of major rectal bleeding after TRUS biopsy, we recommend the establishment of centralized databases or registries forthwith to prospectively capture such data. To the best of our knowledge, this is the first comprehensive look specifically at the management of post-TRUS biopsy rectal bleeding.

The Role of Stem Cells for Reconstructing the Lower Urinary Tracts.

BACKGROUND: The urinary bladder and urethra comprise the lower urinary tracts. Pathological conditions that affect both structures necessitate reconstructive urological intervention with autologous tissue sources that cause neuromechanical and metabolic complications. Stem-cell therapies may offer an attractive alternative as they can replicate important host derived cellular functions such as mitosis, proliferation, differentiation and apoptosis. OBJECTIVE: To provide an overview on the application of stem cell therapies for regenerating the lower urinary tracts and to discuss factors that need to be addressed before stem-cells can be reliably introduced into clinical urological practice. RESULTS: Advantages of stem cells in reconstructive urology are their ability to self-renew and their durability. Mesenchymal stem cells (MSCs), embryonic stem cells (ESCs) and adult stem cells (ASCs) demonstrate excellent urological regenerative properties. Repairing defective lower urinary tract structures with various stem-cell derived therapies has been widely reported with encouraging results in vitro and in pre-clinical in vivo trials. Ethical considerations, cost, regulation, manufacturing and reimbursement need to be fully transparent before stem-cells are routinely applied to urological patients. International collaboration with consensus guidelines should be considered to facilitate standards that allow safe use of stem-cell therapies in urology. CONCLUSION: Stem cells therapies in urology are developing rapidly with many important achievements to date. Despite promising in vitro and pre-clinical data; implementation of stem cells into daily urological practice is not imminent. Further investigation is required to determine whether stem-cells will provide better clinical outcomes than current urological tissue replacement strategies.

A prospective audit on the effect of training and educational workshops on the incidence of urethral catheterization injuries.

INTRODUCTION: The incidence of iatrogenic urethral catheterization (UC) injuries is approximately 0.3%. Resultant complications are associated with patient morbidity and unnecessary healthcare costs. Our aim was to investigate whether educational training workshops decreased the incidence of UC-related injuries. METHODS: A prospective audit was performed to calculate incidence, morbidity, and costs associated with iatrogenic UC injury from January to July 2015. Educational workshops were then conducted with healthcare staff and training modules for junior doctors. UC-related incidence, morbidity, and costs in the subsequent six-month period were recorded prospectively and compared with the previous data. RESULTS: The incidence of iatrogenic UC injuries was reduced from 4.3/1000 catheters inserted to 3.8/1000 catheters after the intervention (p=0.59). Morbidity from UC increased in the second half in the form of increase in cumulative additional inpatient hospital stay (22 to 79 days; p=0.25), incidence of urosepsis (n=2 to n=4), and need for operative intervention (n=1 to n=2). The cost of managing UC injuries almost doubled in the period after the training intervention (€50 449 to €90 100). CONCLUSIONS: Current forms of educational and training interventions for UC did not significantly change morbidity or cost of iatrogenic UC injuries despite a decrease in incidence. Improved and intensive training protocols are necessary for UC to prevent avoidable iatrogenic complications, as well as a safer urethral catheter design.

Exploring mechanisms involved in renal tubular sensing of mechanical stretch following ureteric obstruction.

Tubular mechanical stretch is the key primary insult in obstructive nephropathy. This review addresses how the renal tubular epithelium senses and responds to mechanical stretch. Using data from renal and nonrenal systems, we describe how sensing of stretch initially occurs via the activation of ion channels and subsequent increases in intracellular calcium levels. Calcium influxes activate a number of adaptive and proinjury responses. Key among these are 1) the activation of Rho, consequent cytoskeletal rearrangements, and downstream increases in focal adhesion assembly; and 2) phospholipase activation and resultant mitogen-activated protein kinase activation. These early signaling events culminate in adaptive cellular coupling to the extracellular matrix, a process termed the cell strengthening response. Direct links can be made between increased expression of genes involved in the development of obstructive nephropathy and initial sensing of mechanical stretch. The review illustrates the repercussions of mechanical stretch as a renal stress stimulus, specific to ureteric obstruction, and provides an insight into how tubular responses to mechanical stretch are ultimately implicated in the development of obstructive nephropathy.