Archivio Italiano di Urologia e Andrologia

Development and internal validation of El-Shazly-Buchholz’s nomogram to predict postoperative complications after PCNL: A multicenter study

Wed, 18 Dec 2024 00:00:00 +0000

Introduction: A model to predict the risk of surgical complications following percutaneous nephrolithotomy (PCNL) could be a useful tool to guide clinical decision-making. The aim of this study was to develop a simple and widely applicable stratification tool to be used for patient counseling, surgical planning, evaluation of outcomes, and academic reporting.

Methods: Data of patients who underwent PCNL were retrieved from the database of the collaborating centers including demographics of patients, characteristics of their stones and urinary tracts, and perioperative data. The primary outcome was the development of postoperative complications. Data were randomly split into a training dataset (85%) and a validation dataset (15%). A univariate and multivariate logistic regression analysis of the training dataset was performed to identify independent predictors of postoperative complications. Model variables were used to construct a nomogram that was internally validated on the testing dataset by measuring calibration, discrimination, and plotting the decision curve.

Results: Six hundred thirty one patients (245 Males) with a median (IQR) age of 49 (37-56) years were included. Post-operative complications occurred in 147 (23.3%) patients. Significant predictors of complications included preoperative urine culture (p < 0.001), largest stone diameter (p = 0.02), and intraoperative blood loss (p = 0.002). A nomogram was developed from the predictors and applied to the validation dataset showing an area under the curve (95%CI) of 66.4% (52.2;80.6).

Conclusions: This new scoring system emphasized patient characteristics and operative details rather than stone characters to predict the morbidity of PCNL. Furthermore, it should facilitate risk adjustment, enabling physicians to better define the nephrolithiasis disease continuum and identify patients who should be referred to tertiary care centers.

Ten years’ single surgeon experience of excision and primary anastomosis urethroplasty for traumatic urethral stricture: an analysis of risk factors for urethral stricture recurrence

Thu, 23 Jan 2025 00:00:00 +0000

Introduction: Excision and primary anastomosis (EPA) urethroplasty is the standard treatment for traumatic urethral strictures, but managing them remains challenging for urologists. Identifying factors leading to EPA urethroplasty failure benefits both patients and surgeons. This study aims to analyze risk factors for urethral stricture recurrence after one-year follow-up of EPA urethroplasty.
Materials and methods: Data on male patients undergoing EPA urethroplasty at the Urology Department of Saiful Anwar General Hospital from January 2013 until December 2023 were prospectively recorded. Successful urethroplasty, defined as the absence of additional treatment necessity, was assessed until 12 months follow-up. Demographic data, time to surgery, stricture etiology, comorbidities, prior urethral interventions, and operation steps were recorded. Univariate and multivariate Cox regression analyses were performed using IBM SPSS Statistics version 21.
Result: Total 95 patients were observed, and 89 patients were included, averaging 41.2 ± 15.59 years old. EPA urethroplasty succeeded in 91% of cases over a median follow-up of 16.3 months. Pelvic fracture urethral injury (PFUI) was the predominant etiology in 74% of cases, with an average stricture length of 25.4 ± 16.3 mm. The average time to surgery was performed on average 6.67 ± 4.07 months after diagnosis. In univariate analysis, body mass index (BMI), time to surgery, and stricture length were associated with urethral stricture recurrence. However, only time to surgery showed a significant association in multivariate analysis.
Conclusions: Obesity, the length of the stricture, and delayed surgical intervention are associated with an increased risk of urethral stricture recurrence in patients following EPA. EPA urethroplasty demonstrates a high success rate in managing traumatic urethral strictures.

Theobromine for treatment of uric acid stones and other diseases

Alberto Trinchieri — Thu, 21 Nov 2024 00:00:00 +0000

Theobromine (or 3,7-dimethylxanthine) is a natural alkaloid present in cocoa plant and its derivatives, such as chocolate. About 20% of ingested theobromine is excreted unchanged in the urine. Theobromine also derived from caffeine that is metabolized into theobromine by 12%. The primary metabolites of theobromine are 3-methylxantine, 7-methylxantine, 7-methyluric acid and 3,7-dimethyluric acid. Theobromine has an inhibitory activity of uric acid crystallization, because it has a structural pattern very similar to uric acid and can substitute uric acid molecules in the corresponding uric acid crystals, making them longer and thinner and decreasing their growth rate. Theobromine also favors the dissolution of crystals by decreasing supersaturation of uric acid by forming aggregates with uric acid through hydrogen bonds and aromatic stacking interactions (-stacking bonds) increasing urinary solubility of uric acid. Theobromine can be used for uric acid stone dissolution in combination with alkalinization to reduce the dose of citrate, thus preventing excessive alkalinization and the risk of formation of sodium urate crystals. Theobromine could also be used to treat patient with xanthine stones that cannot be dissolved by alkalinization because the solubility of xanthine is relatively independent of urinary pH. A metabolite of theobromine, 7-methylxanthine, has the potential to be used for the prevention of the formation of sodium urate crystals in the synovial fluid of gouty patients.