[Evaluation of the Effects of Long-Term Indwelling Ureteral Stents on Preserving Renal Parenchyma and Function in Patients with Ureteral Stenosis].

Although ureteral stenting is a common conservative treatment for ureteral stricture, it is unclear whether a long-term indwelling ureteral stent protects the kidney against parenchymal atrophy and functional deterioration. In this study, we evaluated the changes in renal parenchymal thickness (RPT) and estimated the glomerular filtration rates (eGFR) in patients with indwelling ureteral stents for one year or more. As a control, we also evaluated changes in RPT associated with indwelling percutaneous nephrostomy (PNS) for one year or more. Polymer ureteral stents were used and replaced every three months. RPT was measured using computed tomography (CT). Totally, 69 renal units in 55 patients with baseline and follow up CT scans available were enrolled. The median follow-up period was 29 months. The etiologies of ureteral obstruction were malignant and benign disease in 27 and 28, respectively. RPT was reduced obviously in most cases. At 1 year, the median reduction rate of RPT was 17.3% in unilateral cases, which was significantly higher than that in the healthy contralateral kidney. There was a strong correlation between eGFR and total RPT including the contralateral kidney. The reduction rate of RPT in kidneys with ureteral stents including bilateral cases was also significantly higher than that in 39 renal units of 35 patients with PNS. The results of this study suggest that the long-term efficacy of indwelling ureteral stents in preserving renal function is limited. Regular imaging may be essential to evaluate the residual renal function.

[A Case of Fibroepithelial Polyp that was Difficult to Distinguish from Renal Pelvic Carcinoma].

A 56-year-old woman presented with left flank pain. Computed tomography revealed hydronephrosis and a 35 mm mass in the left renal pelvis. Ureteroscopy revealed a white elevated lesion in the left renal pelvis. Tissue biopsy was performed and the histological findings showed no evidence of malignancy. Urine cytology was class III. Based on these results, we could not completely rule out malignancy. Left retroperitoneoscopic nephroureterectomy was performed and a pedunculated white mass was found in the renal pelvis. The pathological diagnosis was a fibroepithelial polyp of the renal pelvis. Fibroepithelial polyps in the urinary tract are relatively rare, and those in the renal pelvis even more so. When the preoperative diagnosis shows no malignant findings, fibroepithelial polyps should be considered as a differential diagnosis.

Efficacy and safety of desmopressin orally disintegrating tablets 25 and 50 µg in male patients with nocturia: A Japanese real-world multicenter clinical study.

OBJECTIVES: To clarify Japanese real-world clinical data on the use of desmopressin 25 and 50 µg orally disintegrating tablets (ODT) for male patients with nocturia and evaluate the predictive factors to improve nighttime frequency. METHODS: We retrospectively accumulated real-world clinical data from 27 institutions in Japan. Male patients with two or more episodes of nocturia who received desmopressin ODT for nocturnal polyuria (NP) from 2019 through 2021 were included. The primary endpoint was the change of nighttime frequency until 3 months after desmopressin administration. The secondary endpoints were to clarify the persistence rate, adverse events, and predictive factors of decreasing nighttime frequency. RESULTS: A total of 118 patients were eligible to participate in this study. The persistence rate of desmopressin on the Kaplan-Meier curve at week 12 was 51.3. The reason for discontinuation was mainly the occurrence of adverse events in 67 patients (56.8%), particularly hyponatremia in 7 patients (5.9%). Nighttime frequencies at baseline, - 1 month and 1 - 3 months after desmopressin administration were 4.1 ± 1.3, 2.9 ± 1.4 (P < .01), and 2.6 ± 1.3 (P < .01), respectively. The mean nighttime urine volume voided at baseline was significantly larger in patients whose nighttime frequency decreased by two or more times than in those with a decrease of less than two times. CONCLUSIONS: Desmopressin 25 and 50 µg ODT treatments are feasible for male patients with NP in Japanese real-world clinical practice. Patients with higher voided volumes, particularly in the nighttime, may have great benefit from desmopressin.