Background: The stricture-formation rate following ureteroscopy ranges from 0.5 to 5% and might amount to 24% in patients with impacted ureteral stones. The pathogenesis of ureteral stricture formation is not yet fully understood. It is likely that the patient and stone characteristics, as well as intervention factors, play a role in this process. In this systematic review, we aimed to determine the potential factors responsible for ureteral stricture formation in patients having impacted ureteral stones. Methods: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) criteria, we conducted systematic online research through PubMed and Web of Science without a time restriction, applying the keywords “ureteral stone”, “ureteral calculus”, “impacted stone”, “ureteral stenosis”, “ureteroscopic lithotripsy”, “impacted calculus”, and “ureteral strictures” singly or in combination. Results: After eliminating non-eligible studies, we identified five articles on ureteral stricture formation following treatment of impacted ureteral stones. Ureteral perforation and/or mucosal damage appeared as key predictors of ureteral stricture following retrograde ureteroscopy (URS) for impacted ureteral stones. Besides ureteral perforation stone size, embedded stone fragments into the ureter during lithotripsy, failed URS, degree of hydronephrosis, nephrostomy tube or double-J stent (DJS)/ureter catheter insertion were also suggested factors leading to ureteral strictures. Conclusion: Ureteral perforation during surgery might be considered the main risk factor for ureteral stricture formation following retrograde ureteroscopic stone removal for impacted ureteral stones.

Urinary bladder cancer is one of the most common malignancies of the urinary tract. Ion channels and calcium homeostasis are involved in almost all basic cellular mechanisms. The transient receptor potential cation channel subfamily M (TRPM) takes its name from the melastatin protein, which is classified as potential tumor suppressor. To the best of our knowledge, there have been no previous studies in the literature investigating the role of these ion channels in bladder cancer. The present study aimed to determine whether bladder cancer is associated with mRNA expression levels of TRPM ion channel genes, and whether there is the potential to conduct further studies to establish novel treatment modalities. The present study included a total of 47 subjects, of whom 40 were bladder cancer patients and 7 were controls. Following the histopathological evaluation for bladder carcinoma, the mRNA and protein expression of TRPM were examined by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and immunohistochemistry in tumor and normal tissues, in order to determine whether there is a difference in the expression of these channels in tumor and normal tissues. Immunoreactivity for TRPM2, TRPM4, TRPM7 and TRPM8 was observed in epithelial bladder cells in the two groups. RT‑qPCR revealed a significant increase in TRPM7 expression in bladder cancer tissue compared to the controls (healthy bladder tissue), whereas no differences in TRPM2 or TRPM4 expression levels were observed. There were significant reductions in the expression levels of TRPM5 and TRPM8 in bladder cancer tissues. In the present study, the effects of TRP ion channels on the formation of bladder cancer was investigated. This study is instructive for TRPM2, TRPM4, TRPM5, TRPM7 and TRPM8 and their therapeutic role in bladder cancer. The results support the fact that these gens can be novel targets and can also be tested for during the treatment of bladder cancer.

Interstitial cystitis (IC)/bladder pain syndrome (BPS) is a challenging disease, affecting thousands of people all around the world, especially women. Although there have been numerous theories regarding IC/BPS etiology, the physiopathology of the disease still remains unclear and there is a lack of certain treatment. The aim of the study was to assess the role of nerve fibers and nerve growth factor (NGF) in the etiopathogenesis of IC/BPS symptoms by demonstrating if there is a correlation between urine NGF levels, amount of peripheral nerves in bladder mucosa and symptom severity. A prospective clinical study was conducted with 15 IC/BPS patients and 18 controls. Urine NGF levels were measured by enzyme-linked immunosorbent assay (ELISA). Bladder punch biopsies were obtained from 15 IC/BPS patients and 9 controls. Immunohistochemistry was performed for S-100 to highlight peripheral nerve twigs in bladder mucosa. The O'Leary-Sant Interstitial Cystitis Symptom and Problem Index (OSICSPI) was used to assess symptom severity and effects of the disease on the patients' life. NGF normalized to urine creatinine (NGF/Cr) levels in IC/BPS patients were significantly higher than in controls, 0.34 ±0.22 and 0.09 ±0.08 pg/mL: mg/dL, respectively (p < 0.001). The mean symptom score in IC patients was 12.27 ±2.4 (median: 12) and the mean problem score was 10.9 ±2.3 (median: 12). The mean mucosal nerve (S-100 stained) area in the IC/BPS group was significantly higher than in the controls, 2.53 ±1.90 vs 1.0 ±0.70, respectively (p = 0.018). In correlation analyses, the NGF/Cr level in IC/BPS patients was found significantly correlated with the O'Leary-Sant IC Symptom and Problem Index scores independently (p = 0.001 and p = 0.028, respectively). NGF seems to be a promising biomarker in IC/BPS. It may help clinicians in diagnoses and patient follow-up. Thus, unnecessary, expensive and invasive tests, interventions and treatments might be avoided.

Introduction: Chronic kidney disease (CKD) is a major health issue worldwide, which leads to end-stage renal failure and cardiovascular events. Neutrophil to lymphocyte ratio (NLR) is a surrogate marker of inflammation and has been widely studied in malignancies, hypertension, heart diseases, and vascular diseases. In this study, we aimed to investigate if NLR represents renal reserve and function after partial or radical nephrectomy. Methods: We conducted a retrospective study consists of patients who had undergone radical/partial nephrectomy in our hospital and/or who admitted to urology and nephrology clinics as an outpatient. Patients were divided into four groups: Group 1 (n = 46): Healthy controls; Group 2 (n = 50): Patients who had undergone unilateral partial nephrectomy; Group 3 (n = 46): Patients who had gone unilateral nephrectomy; Group 4 (n = 82): Patients who had CKD. Results: The mean NLR of each group was as follows: Group 1: 2.14 ± 0.73; Group 2: 3.52 ± 3.74; Group 3: 3.64 ± 3.52, and Group 4: 3.53 ± 2.30. NLR was lower in Group 1 compared to other groups but statistically significant difference was observed only between Group 1 (control) and Group 4 (CKD), 2.14 ± 0.73 versus 3.53 ± 2.30 (p = .005). In non-parametric correlation analysis NLR was found negatively correlated with GFR and positively correlated CKD stage (p = .028 for both correlations). Conclusions: The NLR may constitute a practical predictor of CKD besides Cr in patients who had undergone partial or radical nephrectomy.

Objective: To determine the possible factors effecting stone-free status (SFS) after single-session retrograde intrarenal surgery (RIRS) for renal stones. Material and methods: We retrospectively analyzed the charts of 100 consecutive patients who underwent RIRS. Unilateral procedures performed for single renal stones were included in the study. The studied parameters included patient demographics, stone characteristics (size, volume, location and attenuation according to Hounsfield unit [HU]), operation time, presence of preoperative double-J stent (DJS), use of ureteral access sheath (UAS) and SFS. Results: The study population consisted of 100 patients where 43 of them were stone free and remaining 57 had residual stones. The mean age of the patients was 47.2±13.4 years. The mean stone size (largest dimension), stone attenuation and stone volume were 14.8±5.8 mm, 1010±416 HU and 937±929 mm3, respectively. The mean operative time was 60.8±24.2 minutes. Mean stone size, volume and HU were higher in the RS group compared to SF group but without any statistically significant difference, 15.2±6.1 vs. 14.2±5.3 mm, 1056±1037 mm3 vs. 780±745 mm3 and 1061±374 HU vs. 942±462 HU, respectively (p=0.490, p=0.135 and p=0.226). In multivariate regression analysis stone location and UAS use were found to be the significant predictors of SFS. Patients with lower pole stones are 2.25 times likely to have residual stones after RIRS compared to patient’s having stones at other localizations (p<0.001). Conclusion: Stone volume could be a more reliable parameter than stone size in predicting RIRS success. Lower pole stone location and UAS use could be considered the most significant predictors of SFS after single session RIRS for single renal stones. Cite this article as: Tonyalı Ş, Yılmaz M, Karaaslan M, Ceylan C, Işıkay L. Prediction of stone-free status after single-session retrograde intrarenal surgery for renal stones. Turk J Urol 2018; 44(6): 473-7.