Background: Safety and survival during and after donor nephrectomy (DN) are one of the main concerns in living kidney donors (LKDs). Therefore, kidney (left/right) to be procured should be determined after considering the difficulty of DN, as well as the preservation of remnant renal function (RRF). In this prospective study, we investigated the roles of computed tomography volumetry (CTV) in split renal function (SRF) and established a predictive model for RRF in LKDs. Methods: We assessed 103 LKDs who underwent DN at our institute. The Volume Analyzer SYNAPSE VINCENT image analysis system were used as CTV. RRF was defined as the estimated glomerular filtration rate (eGFR) 12 months after DN. The association between various factors measured by CTV and RRF were investigated, and a role of CTV on prediction for RRF was assessed. Results: The median age and the preoperative eGFR were 58 years and 80.7 mL/min/1.73m², respectively. Each factor measured by CTV showed an association with RRF. The ratio of remnant renal volume to body surface area (RRV/BSA) could predict RRF. In addition, RRV/BSA could predict RRF more accurately when used together with age and 24-h creatinine clearance (CrCl). Conclusions: Our findings suggest that RRV/BSA measured by CTV can play an important role in predicting RRF, and a comprehensive assessment including age and CrCl is important to determine the kidney to be procured.

Background: Transplant renal artery dissection is a rare and serious event that can cause allograft dysfunction and activation of the renin–mediated renovascular hypertension. Most cases are induced by percutaneous transluminal angioplasty, arteriosclerotic disease, or fibromuscular dysplasia. We observed a case of transplant renal artery dissection induced by unusual causes during kidney transplantation. Case presentation: A 35-year-old woman, whose mother donated a kidney to her, underwent ABO-incompatible living kidney transplantation. The allograft had one renal artery and vein that were anastomosed to the internal iliac artery and external iliac vein, respectively. Although careful handling was performed in all procedures including vascular clamping, Doppler ultrasonography (US) immediately after reperfusion showed an increase in the systolic blood velocity and urine output was not observed. Arterial anastomotic stenosis was suspected, but upon exploration, a renal artery dissection was detected in the middle portion of the donor artery. The part of the transplant renal artery was resected, and cold reflux was started again. At the resected part of transplant renal artery, dissection was identified. After re-anastomosis, Doppler US revealed that the blood flow of the renal artery was adequate without an increase in the systolic blood velocity, and sufficient blood flow was observed throughout the allograft. Urine output was also observed as soon as blood flow returned, and serum creatinine level decreased to 0.95 mg/dL after surgery. The cause of injury might have been vascular clamping in order to drain the air and check bleeding at the anastomosis. Conclusions: Our case reaffirmed that careful handling is needed in all procedures, including donor nephrectomy, cannulation for transplant perfusion, vascular clamping, and anastomosis, even without any evidence of arteriosclerosis. Kidney transplant recipients commonly have atherosclerosis and hypertension, which are risk factors for arterial dissection. Early diagnosis and intervention can lead to the prevention of allograft dysfunction. Therefore, close monitoring of allograft blood flow by Doppler US during surgery should be considered.

Page kidney phenomenon is caused by strong renal parenchymal compression and leads to renal hypoperfusion and microvascular ischemia, resulting in renal dysfunction and hypertension. Although the development of Page kidney phenomenon in allograft is rare, most of its cases are induced by allograft biopsy or trauma. We observed a case of Page kidney phenomenon that was induced by unusual causes immediately after kidney transplantation. A 66-year-old man, whose wife donated a kidney, underwent ABO-compatible living kidney transplantation. The allograft had three renal arteries that were trimmed and formed into one piece on the back table, and subsequently, it was anastomosed to the internal iliac artery. Intraoperative Doppler ultrasonography (US) revealed adequate blood flow of each renal artery. Urine output was also observed as soon as allograft blood flow was reperfused. After the surgery, the urine output decreased, and serum creatinine level increased to 6.0 mg/dL. Doppler US did not show evidence of acute rejection, ureteral obstruction, or anastomotic stenosis of the renal arteries. On postoperative day 7, surgical exploration was performed and revealed that the blood flow of each renal artery was adequate but subcapsular hematoma was detected at the upper pole of the allograft. Capsulotomy and hematoma evacuation were performed. Subsequently, urine output increased and serum creatinine level decreased up to 1.7 mg/dL. Allograft sample was obtained 1 h after the transplantation from the lower pole of the allograft. Although the cause of subcapsular bleeding was unclear in this case, a small cyst of the allograft, which might have ruptured during donor nephrectomy, was located in the middle of the hematoma, and oozing around the cyst was observed. Our case indicated that the small ruptured cyst of the allograft could be the cause of subcapsular hematoma and Page kidney phenomenon. Subcapsular hematoma caused by oozing over time could be difficult to diagnose using Doppler US, and thus, other imaging modalities, such as computed tomography, should be considered. Knowledge of the Page kidney phenomenon in the allograft can lead to early diagnosis and intervention, resulting in better outcomes for recipients with allograft dysfunction.

Background: Photodynamic diagnosis-assisted transurethral resection of bladder tumor reduces the risk of intravesical recurrence compared with conventional white light-transurethral resection of bladder tumor. However, the patient burden of costs for photodynamic diagnosis-transurethral resection of bladder tumor is higher than that for white light-transurethral resection of bladder tumor per installment, and the impact of the medical economics of photodynamic diagnosis-transurethral resection of bladder tumor is unclear. Therefore, we evaluated the Japanese health care system-based cost-effectiveness of photodynamic diagnosis-transurethral resection of bladder tumor compared with that of white light-transurethral resection of bladder tumor.Methods: We conducted a retrospective chart review of 100 patients who underwent initial white light- or photodynamic diagnosis-transurethral resection of bladder tumor for non-muscle invasive bladder cancer from February 2012 to August 2019. Cumulative intravesical recurrences during 1000 post-operative days after the initial transurethral resection of bladder tumor were counted. Furthermore, the cumulative costs were calculated using the Diagnostic Procedure Combination and Per-Diem Payment System unique to Japan. The costs/year/person calculated using the person-year method was compared between the white light- and photodynamic diagnosis-transurethral resection of bladder tumor.Results: Among the 100 patients, 40 (40%) and 60 (60%) underwent the initial white light- and photodynamic diagnosis-transurethral resection of bladder tumor, respectively. The cumulative incidence of bladder recurrence requiring hospitalization and transurethral resection of bladder tumor was 20 and 5% for the white light-transurethral resection of bladder tumor and photodynamic diagnosis-transurethral resection of bladder tumor, respectively. The costs for hospitalization and surgical procedures per white light- or photodynamic diagnosis-transurethral resection of bladder tumor were 348 228 and 481 820 Japanese yen, respectively. The cost/year/person by the person-year method was 8073 and 8557 Japanese yen for the white light- and photodynamic diagnosis-transurethral resection of bladder tumor, respectively.Conclusions: The cost/year/person for hospitalization and surgical procedures was slightly different between the white light- and photodynamic diagnosis-transurethral resection of bladder tumor. Furthermore, photodynamic diagnosis-transurethral resection of bladder tumor can reduce intravesical recurrence and is more cost-effective than white light-transurethral resection of bladder tumor.

Complete metastasectomy (CM) in metastatic renal cell carcinoma (mRCC) has demonstrated efficacy in the cytokine era, but its effectiveness in the era of tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs) remains unclear. A multi-institutional database included clinicopathological data of 367 patients with mRCC. Patients were divided into two groups: the CM group and the non-CM group. These two groups were compared before and after propensity score matching (PSM). Cox proportional hazard models were used to detect factors associated with disease-free survival (DFS) and overall survival (OS) from mRCC diagnosis. The CM group showed a significant association with longer overall survival compared to the non-CM group in the PSM-unadjusted cohorts (p < 0.001, hazard ratio 0.49, 95% confidence interval 0.35–0.69), but no superiority was noted in the adjusted cohorts. The median DFS after CM was 24 months, with no significant differences based on relapse timing. Notably, the international metastatic RCC database consortium risk categories and metastatic burden were associated with DFS. This study supports the potential of CM in mRCC management during the TKI/ICI era, although limitations including sample size and selection bias need to be considered.