Urolithiasis最新文献

To evaluate the outflow of the sheath of pediatric nephroscope with access sheath of various sizes in the boundaries of a standardized in vivo experimental set-up. Two female porcines of 10 kg each were used in this experiment. The experiment was performed with the use of a 7.5Fr Pediatric Nephroscope and two different access sheaths; 8.5/9.5Fr and 11/12Fr. The measurements of outflow were performed with the use of gravity irrigation and manual pump irrigation. Additionally, the presence of accessory instruments in the working channel was evaluated. Using the 8.5/9.5Fr access sheath, the outflow with gravity irrigation was estimated at 12.3±1.3 ml/min, while under manual pump irrigation conditions, the outflow was calculated at 13.9±1.6 ml/min. The presence of Laser Fiber in the working channel diminished the outflow to 10.05±1.85 ml/min and 12.4±1.9 ml/min with the use of gravity and manual pump irrigation, respectively. Moreover, the outflow was estimated at 5.05±1.5 ml/min and 5.8±1.4 ml/min with the utilization of gravity and manual pump irrigation, respectively, when the basket was inserted into the working channel. The outcomes were ameliorated with the use of 11/12Fr access sheath. Both access sheaths used in this experimental study presented adequate outflow, even when the working channel was used for the introduction of instruments. Although no monitoring of IRP and temperature was performed in our experiment the outflow values we recorded probably correspond to safe changes in IRP and temperature.

To evaluate the efficacy and safety of a Flexible and Navigable Suction Ureteral Access Sheath (FANS) in flexible ureteroscopic lithotripsy (FURL) under local anesthesia for renal stones 2-4 cm. We retrospectively analyzed clinical data from patients with renal stones 2-4 cm who underwent local anesthesia FURL from January 2023 to December 2024. Patients were divided into two groups based on the type of sheath used: FANS or traditional ureter access sheath (T-UAS) group. Demographic data and perioperative indicators were compared. A total of 372 patients were included in the study, with 187 in the FANS and 185 in the T-UAS group. FANS achieved an 78.6% one-time stone-free rate (SFR) (vs. 57.8% in T-UAS, P < 0.001), with significantly lower postoperative fever (2.1% vs. 8.1%) and steinstrasse (1.1% vs. 5.9%). FANS enhances FURL efficacy for 2-4 cm renal stones under local anesthesia, provides an alternative to percutaneous nephrolithotomy (PCNL) for select patients.

This study aimed to evaluate the impact of costovertebral angle (CVA) width on the outcomes of percutaneous nephrolithotomy (PCNL), particularly regarding stone-free rates, bleeding, complication rates, and the need for additional interventions. A total of 181 patients who underwent prone PCNL between January 2018 and July 2024 at a single center were retrospectively analyzed. CVA was measured using preoperative standing direct urinary system X-rays. Patients were categorized into three groups based on CVA: <45°, 45-55°, and > 55°. Operative and postoperative parameters including hemoglobin/hematocrit decrease, transfusion requirement, complications (Modified Clavien-Dindo Classification), stone-free rate, and access type were evaluated and statistically analyzed. Hemoglobin and hematocrit decreases were significantly correlated with narrower CVAs (p = 0.041 for both). No significant relationship was observed between CVA and stone-free status, transfusion need, or complication rates. Although patients with CVA < 45° had a higher rate of complications (38.9%) and greater blood loss, these findings did not reach statistical significance. Intercostal access, more frequently required in patients with narrow CVA, was associated with higher but not statistically significant complication rates. Narrow CVA may pose a greater challenge during PCNL due to limited nephroscope maneuverability, potentially increasing intraoperative bleeding. However, it does not significantly affect overall surgical success or complication rates. CVA can be considered a useful anatomical parameter during preoperative planning, especially when selecting the access route.

Subepithelial papillary calcifications, encompassing both Randall's plaques (interstitial) and Randall's plugs(intraluminal), are established niduses for stone formation, yet their distribution and determinants in stone-naïve individuals remain poorly characterized. We hypothesized that subclinical papillary calcifications are present in non-stone-formers and associated with urinary and clinical risk factors similar to those in stone formers. In this retrospective cross-sectional study, we analyzed 50 patients undergoing nephrectomy for renal or upper urinary tract cancer (June 2019-January 2023). Patients with prior stone disease, calcium/vitamin supplementation, or metabolic disorders were excluded. High-resolution micro-computed tomography (micro-CT, 20 μm voxels) quantified mineral-to-parenchyma (M/P) ratios across papillary zones, and osteopontin (OPN) immunohistochemistry was performed on matched sections. Given the 20 μm spatial resolution limit of micro-CT, any papillary tip calcified lesion (PCL) ≥ 1 mm³ was considered clinically relevant; such lesions were present in 46% of kidneys. PCL + patients were older, more frequently hypertensive, and exhibited lower urine volume (median 1200 vs. 1600 mL, p < 0.001), lower urinary citrate (p = 0.002), higher urine specific gravity (p = 0.001), and elevated M/P ratios in the middle medullary zone (p = 0.003). OPN staining was increased in loops of Henle in PCL + cases and correlated with mineral burden. Multivariable analysis identified lower urine volume, higher urinary calcium, and hypertension as independent predictors of PCL (area under curve = 0.93). These findings indicate that PCLs are common in stone-naïve kidneys and are associated with specific urinary and systemic risk factors. Early interventions targeting urine chemistry and vascular health may influence mineral deposition and delay kidney stone development.

On-treatment 24-h urine testing rates are low outside of tertiary care centers. A common criticism is the paucity of evidence demonstrating the optimization of urinary parameters correlates with reduced stone recurrence. Using standard and novel analytic approaches, we sought to evaluate whether improvements in 24-h urine parameters associated with decreased symptomatic stone recurrence. Kidney stone patients who underwent multiple 24-h urine tests and had an initial parameter abnormality were identified from a prospective database. A novel 24-h urine severity score was calculated at both the initial and subsequent tests and used to stratify patients. Negative binomial regression was used to evaluate the impact of analyte changes on stone recurrence. Two hundred patients met inclusion criteria. Low voided volume, hypercalciuria, hyperoxaluria, hypocitraturia and low pH were identified in 56%, 28%, 40%, 49% and 35% respectively. Patients with hypercalciuria and hypocitraturia who consistently normalized these values showed decreased recurrence (p < 0.001). Increasing initial 24-h urine severity scores associated with increased stone recurrence (0.09, 0.18 and 0.31 stone events per year for the lowest, 25-75th and highest quartiles, p < 0.001). On multivariable analysis, severity score improvement or stabilization was associated with reduced risk of recurrence across all quartiles (RRR 0.319 to 0.591, all p < 0.001). Consistent control of 24-h urine parameters was associated with decreased stone recurrence. Not only did novel 24-h urine composite severity scores based on initial 24-h urines independently predict stone recurrence, improvements in this score over time also predicted decreased recurrence.