To evaluate the efficacy and safety of the flexible ureteroscopy (fURS) with a flexible and negative suction ureteral access sheath (FANS) versus traditional sheath for patients with infectious upper urinary tract stones (IUUTS). A total of 185 patients were enrolled, with 93 assigned to the FANS group and 92 to the traditional UAS group. The primary outcome was the stone-free rate (SFR) at the first postoperative day. Secondary outcomes included the SFR at 30 days postoperatively, operative time, hemoglobin reduction, length of hospital stay, quality of life (QoL) improvement, incidence of ureteral stricture at 3 months, and surgery-related complications. No significant differences were observed between the two groups in baseline demographics or preoperative clinical characteristics (P > 0.05). The FANS group had significantly lower white blood cell count, C-reactive protein, and procalcitonin levels at 6 and 24 h postoperatively (all P < 0.05). Mean operative time was significantly shorter (P < 0.001), QoL improvement was obviously greater (P < 0.001), and average hospital stay was shorter in the FANS group (P < 0.001). The SFRs on postoperative day 1 and at 30 days were both significantly higher in the FANS group (both P < 0.05). At 3 months, ureteral strictures occurred in three patients in the traditional UAS group and one in the FANS group, a difference that was not statistically significant (P > 0.05). The overall complication rate was significantly lower in the FANS group (P < 0.05). For patients with IUUTS, fURS combined with FANS effectively improves stone clearance efficiency and reduces the risk of postoperative infection.
Classical anatomical teaching describes three ureteral narrowing points as the principal sites associated with ureteral stone localization; however, contemporary imaging studies suggest a more complex distribution. This retrospective study aimed to characterize ureteral stone distributions using detailed vertebral-level mapping complemented by conventional segmental classification and multiplanar stone measurements. Non-contrast computed tomography (CT) images of 398 patients, each contributing a single ureteral stone, were subjected to analysis. Stones were classified according to five anatomical ureteral segments and detailed vertebral levels. Vertical, transverse, sagittal, and maximum stone diameters were measured. The proximal ureter was the most frequent stone location (34.4
We compared 18Fr suction mini-percutaneous nephrolithotomy (SMP) with standard percutaneous nephrolithotomy (sPCNL) for 2–4 cm renal stones in a prospective, single-center, non-randomized cohort and separated three questions: population-average effects, treatment-effect heterogeneity, and the value of acting on that heterogeneity. Among 900 patients, 450 underwent each procedure. Targeted maximum likelihood estimation with cross-validated Super Learner estimated outcome-specific average effects. A Net Clinical Utility (NCU) composite was analyzed with doubly robust estimation, an honest causal forest, and fivefold cross-fitted policy evaluation. SMP-minus-sPCNL differences were +2.7 percentage points for 1-day stone-free rate (95
Vacuum-assisted access sheaths have recently gained interest in percutaneous stone surgery; however, data regarding their use in pediatric patients remain limited. This study compared the perioperative and postoperative outcomes of vacuum-assisted and conventional percutaneous access sheaths in pediatric patients undergoing supine mini-percutaneous nephrolithotomy. Medical records of children younger than 18 years who underwent supine mini-percutaneous nephrolithotomy between January 2022 and January 2026 were retrospectively reviewed. Patients with anatomical anomalies, bilateral procedures, multiple access tracts, or endoscopic combined intrarenal surgery were excluded. A total of 51 patients were included and divided into two groups according to sheath type: conventional percutaneous access sheaths (n = 27) and vacuum-assisted ClearPetra sheaths (n = 24). Baseline demographic and stone characteristics were comparable between the groups. Mean operative time was shorter in the vacuum-assisted group (57.6 ± 21 vs. 65.6 ± 24 min, p = 0.232), whereas fluoroscopy time was slightly longer (74.2 ± 65 vs. 60.6 ± 44 s, p = 0.387); neither difference reached statistical significance. Stone-free rates were comparable between the conventional and vacuum-assisted groups (85.2
The Mayo Adhesive Probability (MAP) score was originally developed to predict adherent perinephric fat in partial nephrectomy. Its role in percutaneous nephrolithotomy (PNL) remains poorly characterized. We aimed to investigate whether MAP score is associated with markers of procedural difficulty and perioperative outcomes in patients undergoing PNL. We retrospectively evaluated 556 consecutive adult patients who underwent PNL between 2020 and 2025. MAP scores were calculated using preoperative non-contrast computed tomography and patients were categorized into low-MAP (< 3) and high-MAP (≥ 3) groups. Procedural difficulty markers included prolonged operative time (> 120 min), multiple access tracts (≥ 2), postoperative hemoglobin decrease ≥ 2 g/dL, residual stone fragments > 4 mm, secondary intervention, tubeless drainage, and trifecta failure. Trifecta failure was defined as the presence of residual stones, postoperative complications, or need for secondary intervention. Multivariable logistic regression analyses were adjusted for age, sex, stone size, stone density, Guy’s score ≥ 3, hydronephrosis grade, and skin-to-stone distance. Among 556 patients, 310 had MAP scores < 3 and 246 had MAP scores ≥ 3. Patients with MAP ≥ 3 had significantly longer operative times (107.8 ± 47.7 vs. 97.7 ± 38.0 min, p = 0.007), greater hemoglobin decrease (2.17 ± 1.22 vs. 1.67 ± 1.07 g/dL, p < 0.001), higher rates of multiple access tracts (18.7
Ureteral stricture is a potentially serious complication following ureteroscopy (URS) for ureteral stones. In the absence of clear guideline recommendations, practices regarding risk factors, prevention, surveillance, and management remain heterogeneous. This study aimed to evaluate multinational urologists’ perceptions and real-world practices related to post-URS ureteral strictures and to develop expert consensus recommendations. A multinational, web-based survey was distributed to practicing urologists worldwide through professional networks and platforms. The questionnaire assessed respondent demographics, URS case volume, perceived incidence and risk factors, preventive strategies, laser settings, postoperative surveillance, and management approaches. Data were analyzed using question-specific denominators. Expert consensus recommendations were developed through a structured Delphi process. A total of 362 urologists from 66 countries participated, with 80.1
Although adiposity is associated with kidney stone disease, the relationship between abdominal fat distribution and urinary calcium excretion remains unclear. We investigated whether the CT-derived visceral-to-subcutaneous fat ratio (VSR) was associated with 24-hour urinary calcium excretion and whether physiologic age modified this association. This retrospective cross-sectional study included 308 adults with nephrolithiasis who underwent preoperative CT, stone removal, and postoperative metabolic evaluation. Participants were stratified into prespecified younger (men aged < 50 years and premenopausal women) and older (men aged ≥ 50 years and postmenopausal women) physiologic-age groups. Multivariable linear regression assessed the association between VSR and urinary calcium excretion and its modification by physiologic age. Results showed that VSR was not associated with urinary calcium excretion in the overall cohort, but its association differed significantly by physiologic age (P for interaction < 0.001). Among younger participants, each 1-unit higher VSR was associated with 2.07 mmol/day greater urinary calcium excretion (95
We investigated the predictive value of standard non-contrast computed tomography (NCCT) measurements, the ureteral dilatation ratio (DDR) and intraluminal urine stasis markers, for spontaneous stone passage (SSP) versus surgical intervention in patients with ureteral stones. We also evaluated ureteral wall thickness (UWT) as a practical clinical marker. This retrospective study included 461 patients diagnosed with ureteral stones via NCCT. Patients were categorised into two groups based on clinical outcomes: the spontaneous passage group (MET; n = 229) and the endoscopic surgery group (URS; n = 232). Stone volume, stone density (HU), UWT, DDR and intraluminal urine attenuation values were measured for all patients. Independent risk factors were identified using a multivariate logistic regression model and clinical cut-off values were determined via ROC curve analysis. Stone volume, density, UWT and hydronephrosis grade were all significantly higher in the URS group. Multivariate regression analysis revealed that increased UWT (OR: 5.03, 95
Urolithiasis remains a significant clinical burden, and accurately predicting stone-free status after retrograde intrarenal surgery (RIRS) is essential for optimizing patient counseling and surgical planning. This study compared the predictive performance of a machine learning–based Random Forest (RF) model with the T.O.HO. scoring system, a traditional prediction tool designed for flexible ureteroscopy. A total of 452 patients who underwent RIRS for renal or proximal ureteral calculi at a single tertiary center were retrospectively analyzed. Preoperative demographic and radiological variables were collected, and postoperative stone-free status was assessed at the third week using KUB radiography or non-contrast CT when clinically indicated. The T.O.HO. score was calculated for each patient. The RF model was trained on 70
Despite major advances in kidney-stone management, the clinical-trial landscape in nephrolithiasis has not been systematically characterized. We performed a 20-year registry-based landscape analysis of interventional kidney-stone trials, focusing on trial design, primary endpoint selection, infrastructure, and dissemination. ClinicalTrials.gov was searched for interventional kidney-stone trials with primary completion dates between June 23, 2005 and June 23, 2025. Trials were categorized by lead sponsor type, study design, center status, intervention category, and primary endpoint domain. Temporal trends in primary endpoint selection were assessed by registration era. Publication status, ClinicalTrials.gov results posting, and intervals from registration to results posting, study start to publication, and primary completion to publication were evaluated among completed trials. A total of 57 trials met inclusion criteria. Most had an academic lead sponsor (49/57, 86.0
To evaluate the feasibility, safety, and efficacy of percutaneous nephrolithotomy (PCNL) performed without retrograde catheterization in the split-leg prone position in selected patients, a single-center, randomized controlled trial was carried out. 140 consecutive patients with renal stones > 2.0 cm were randomly assigned to either no ureteral catheterization split-leg prone position (NUC-SLP) group or the traditional position (TP) group, and underwent PCNL. The primary outcome was first access time. Secondary outcomes included operative time, anesthesia time, stone free rate (SFR), complications, and costs. It was noted in the RCT that, median first access time was comparable between the NUC-SLP and TP groups (10.5 [9.2, 12.5] min vs. 10.5 [8.5, 11.89] min; mean difference (MD) 0.66 min, 95
Kidney stone disease is a prevalent urological condition with rising incidence and high recurrence rates, yet effective pharmacological interventions remain lacking [1] Prostaglandin E₂ (PGE₂) and its receptor EP3 have been implicated in inflammatory kidney injury [1–3], but their role in nephrolithiasis is unclear. This study investigates the role and mechanism of EP3 in calcium oxalate (CaOx) stone formation using in vitro and in vivo models. EP3 expression was significantly upregulated in CaOx-stimulated human renal tubular epithelial cells (HK-2) and in kidney tissues of glyoxylate-induced nephrolithiasis mice. Treatment with the EP3 antagonist DG041 in vitro reduced crystal adhesion, decreased HMGB1 release, and suppressed IL-6 and TNF-α expression. Mechanistically, EP3 antagonism inhibited aberrant intracellular Ca2⁺ elevation and reduced AKT phosphorylation. Virtual screening identified Astragaloside A as a potential EP3 inhibitor. Astragaloside A recapitulated the protective effects of DG041, attenuating crystal adhesion, inflammation, and necroinflammation both in vitro and in vivo. These findings indicate that EP3 mediates crystal-induced renal tubular injury and inflammation via the Ca2⁺/AKT signaling axis. Targeting EP3 may interrupt the "crystal‑injury‑inflammation" cycle in nephrolithiasis, offering a new therapeutic strategy. This study is the first to demonstrate that the EP3 receptor mediates calcium oxalate kidney stone formation through the Ca2⁺/AKT signaling pathway and necroinflammation. EP3 antagonism reduces crystal adhesion, HMGB1 release, and inflammation. Virtual screening identifies astragaloside A as a novel EP3 inhibitor with protective effects in vitro and in vivo, highlighting EP3 as a promising therapeutic target.
Calcium oxalate nephrolithiasis is strongly associated with oxidative stress, renal tubular injury, and inflammation. Natural products rich in polyphenols may serve as promising complementary preventive strategies. This study investigated the antiurolithiatic and renoprotective effects of Rhus coriaria fruit extract in an ethylene glycol-induced rat model of nephrolithiasis. Forty-two male rats were randomized into seven groups (n = 6): control, ethylene glycol (EG), EG + potassium citrate, R. coriaria 250 mg/kg/day, R. coriaria 500 mg/kg/day, EG + R. coriaria 250 mg/kg/day, and EG + R. coriaria 500 mg/kg/day. Nephrolithiasis was induced with 1
Papillary puncture is commonly recommended in percutaneous nephrolithotomy (PCNL) because it is thought to reduce the risk of vascular injury. In patients with multiple renal stones, however, calyceal anatomy and stone distribution can make a strict papillary approach difficult. Non-papillary access may be a practical alternative during mini-PCNL, but its safety and effectiveness remain debated. This study compared non-papillary and papillary access in mini-PCNL for multiple renal stones. This prospective randomized study enrolled 108 patients with multiple renal calculi. Patients were allocated to non-papillary access (n = 53) or papillary access (n = 55). All procedures were performed as mini-PCNL using an 18-Fr tract and holmium: YAG laser lithotripsy. Study outcomes included operative time, hemoglobin drop, stone-free rate (SFR), and perioperative complications. The non-papillary group had a significantly shorter operative time (49 ± 11 min vs. 58 ± 11 min; p < 0.001) as well as shorter fluoroscopy time (median 2.5 vs. 3.3 min; p < 0.001). Single access was achieved in 100
Acute kidney injury (AKI) is a clinical syndrome characterized by a rapid decline in glomerular filtration function caused by multiple factors. Factors such as stones and tumors can lead to AKI following renal obstruction. Renal tubular epithelial cell injury is a key component of the pathophysiological mechanism of ischemic acute kidney injury after obstruction.Oxygen–glucose deprivation (OGD) in HK-2 cells and a mouse model of unilateral ureteral ligation (UUO) were used to investigate the role of Claudin-2 in renal tubular epithelial cell apoptosis in ischemia-induced AKI. In animal experiments, the expression of Claudin-2 protein was decreased, while Bax and Caspase-3 expression were increased, and Bcl-2 expression was decreased in the renal tissue of UUO mice. Similarly, after OGD treatment, Claudin-2 protein expression was decreased, Bax and Caspase-3 expression were increased, and Bcl-2 expression was decreased. Upregulation of Claudin-2 protein expression through lentivirus transfection in OGD-treated HK-2 cells reduced the decline in cell viability and the proportion of apoptotic cells. Additionally, upregulation of Claudin-2 protein expression reduced OGD-induced Caspase-3 expression, while the Bax/Bcl-2 ratio showed no significant change. The expression of Claudin-2 is decreased during acute obstructive kidney injury, which contributes to changes in Caspase-3 apoptotic protein and activates cell apoptosis,while the Bax/Bcl-2 ratio showed no significant change.Claudin-2 protein likely modulates apoptosis through a caspase-3-dependent pathway independent of the Bax/Bcl-2 ratio.
This study aims to evaluate the feasibility of 3D printing in percutaneous nephrolithotomy (PCNL) for the treatment of complex renal calculi. Eighty patients with complex kidney stones admitted to Guangdong Second People’s Hospital for PCNL surgery from October 1, 2021, to December 31, 2024, were randomly assigned to either the 3D printing group (40 cases) or the control group (40 cases). The 3D printing group underwent contrast-enhanced CT scanning of the urinary system. It utilized patient-specific 3D-printed models for preoperative surgical planning, simulated puncture trajectories, and patient consultations to enhance understanding of the procedure. Preoperative interview scores in the 3D printing group were significantly better than those in the control group, indicating improved patient comprehension and satisfaction. In the 3D printing group, 36 patients (90
Postoperative systemic inflammatory response syndrome (SIRS) and sepsis following ureteroscopic lithotripsy (URS) are uncommon but potentially life-threatening complications. No prior study has evaluated large language models (LLMs) for predicting post-URS SIRS/sepsis using exclusively preoperative parameters. This study evaluated the discriminative performance of LLMs in this setting. This retrospective case-control study included 210 patients who underwent URS between January 2024 and December 2025 (42 SIRS/sepsis cases, 168 controls). Risk scores (0-100) were generated using GPT-4o-mini and Gemini 2.5 Flash with guideline-based and intuitive prompting strategies. Discriminative performance was assessed using receiver operating characteristic analysis and area under the curve (AUC). Model comparisons were performed using the DeLong test. Patients who developed SIRS/sepsis were older and more frequently female, with larger stones, higher hydronephrosis grade, lower stone density, increased inflammatory markers (urine WBC, leukocyte esterase, neutrophil-to-lymphocyte ratio), higher rates of positive urine culture, and more frequent radiological inflammatory findings (all p<0.001). Total WBC did not differ between groups (p=0.698). All model-prompt combinations showed high discriminative performance (AUC 0.952-0.973). The highest performance was achieved by the GPT-4o-mini intuitive model (AUC 0.973; sensitivity 92.9%; specificity 95.2%). No significant differences were observed between models or prompting strategies. Performance remained high after excluding patients with positive urine culture or preoperative antibiotic use (AUC 0.896-0.943). LLMs demonstrated high discriminative performance for predicting postoperative SIRS/sepsis using only preoperative data, suggesting potential utility as accessible clinical decision-support tools for perioperative risk stratification in URS. Prospective multicenter validation is required before clinical implementation.
Stone impaction significantly increases the difficulty of ureteroscopic surgery (URS). While various CT-based parameters have been proposed to predict impaction, direct measurement of ureteral wall thickness (UWT) often lacks accuracy due to imaging artifacts and low conspicuity. This study aimed to identify reliable objective factors, particularly the Ureteral Dilation Coefficient (UDC), to predict ureteral stone impaction. We conducted a retrospective analysis of 189 patients who underwent URS between 2022 and 2025. Patients were divided into Impacted (n = 101) and Non-impacted (n = 88) groups based on intraoperative guidewire passage. Impaction was defined intraoperatively based on the inability to pass a guidewire past the stone.All CT images were evaluated using a bowel window with contrast inversion. We measured standard parameters and calculated the UDC. Inter-observer reliability was assessed using Intraclass Correlation Coefficients (ICC). Multivariate logistic regression was used to identify independent predictors and construct the Prediction Risk Estimation(PRE) model, which was validated using Bootstrap and Propensity Score Matching (PSM). ROC curves and Decision Curve Analysis (DCA) were performed to evaluate performance. UDC demonstrated excellent reproducibility (ICC > 0.85). Multivariate analysis revealed that Laterality, Maximum Stone Length (MSL), Ureteral Outer Area HUD Above stone (UOAHUDA), and UDC were independent predictors of impaction. Notably, UDC exhibited the highest Odds Ratio (OR = 8.156, 95
