Predictors of Repeat Surgery and Stone-related Events After Flexible Ureteroscopy for Renal Stones

Recurrent Urinary Stone Formers: Imaging Assessment and Endoscopic Treatment Strategies: A Systematic Search and Review

Background/Objectives: Nephrolithiasis is a heterogeneous disease with a high prevalence and recurrence rate. Although there has been much progress regarding the surgical treatment of stones, a standardized follow-up, especially in recurrent stone formers (SFs), has yet to be decided. This fact leads to the overuse of computed tomography (CT) scans and many reoperations in patients, thus increasing their morbidity and the financial burden on the health systems. This review systematically searched the literature for original articles regarding imaging strategies and endoscopic treatment for patients with recurrent urolithiasis, aiming to identify optimal strategies to deal with these patients. Methods: We systematically searched the Medline database (accessed on 1 April 2024) for articles regarding imaging modalities and endoscopic treatment for patients with recurrent urinary tract lithiasis. Results: No specific follow-up or endoscopic treatment strategy exists for patients with recurrent urolithiasis. CT scan was the imaging modality most used in the studies, followed by X-ray, ultrasonography, and digital tomosynthesis. A transparent algorithm could not be identified. Percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), and ureteroscopy (URS) were used in the studies for endoscopic treatment. PCNL showed the best stone-free (SFr) rate and lowest hazard ratio (HR) for reoperation. RIRS showed superiority over extracorporeal shockwave lithotripsy for recurrent SFs, but fragments over 4 mm increased the recurrent rate. URS has an increased HR for reoperation for bilateral stones. Conclusions: The heterogeneity of urolithiasis leaves urologists without a standardized plan for recurrent SFs. Thus, each patient's follow-up should be planned individually and holistically. Pre-stenting is not to be avoided, especially in high-risk patients, and SFr status needs to be the aim. Finally, CT scans should not be generally overused but should be part of a patient's treatment plan. Prospective studies are required to define SFr status, the size of significant residual fragments, and the modalities of intervention and follow-up.

Stone-event-free survival after ureteroscopic lithotripsy by age: comparison between young and older patients

The aim of this study is to examine stone-event-free survival after ureteroscopic lithotripsy (URSL) and risk factors for stone events by age. We retrospectively collected data of all URSL cases at our institution from 2008 to 2021. A total of 1334 cases were included and divided into young (< 65 years, 792 cases), young-old (65-74 years, 316 cases), old-old (75-84 years, 172 cases), and oldest-old (≥ 85 years, 54 cases) groups. Patient characteristics, surgical outcomes, and postoperative stone events were evaluated. The stone-event-free survival and risk factors were compared between young and older groups. Overall, 214 (16.0%) cases developed stone events during a mean follow-up period of 763 days and the 2-year, 5-year, and 8-year stone-event-free survival rates were 84.5%, 72.2%, and 57.2%, respectively. The numbers of stone events in young, young-old, old-old, oldest-old groups were 133 (16.8%), 53 (16.8%), 21 (12.2%), and 7 (13.0%), respectively. No significant differences were found in stone-event-free survival between the young group and each of the older groups. Residual fragment > 4 mm and stone burden ≥ 15 mm were common risk factors in both young and older groups. Especially in older patients, preoperative stenting, which was most often performed to treat obstructive pyelonephritis, was the third risk factor. In conclusion, stone-event-free survival after URSL was comparable between young and older patients. Residual fragment > 4 mm and stone burden ≥ 15 mm were common risk factors in both groups. Preoperative stenting was an additional risk factor in older patients, suggesting that urinary tract infection may influence stone events.

Long-term follow-up on dusting versus basketing during ureteroscopy: a prospective multicenter trial from the EDGE Research Consortium

In 2018, the Endourology Disease Group for Excellence (EDGE) published a prospective trial comparing dusting versus basketing during ureteroscopy. One hundred fifty-nine patients were included in the original analysis, which found no difference in stone-free rate at 3 months. We report the intermediate and long-term outcomes of patients included in the original trial. Two analyses were performed. At 1-year, a retrospective chart review was performed, and data collected on stone episodes, Emergency Department (ED) visits, hospital admissions and surgical interventions. To obtain long-term outcomes, the four sites with the largest initial accrual were included in a second phase of data collection with updated analyses. The patients from those sites were contacted, re-consented, and data were collected on stone surgical interventions, stone episodes, stone recurrences on imaging, emergency department (ED) visits, and hospital admissions for stone-related care since their original procedure. One-year follow-up data were collected in 111 of the original 159 (69.8%) patients from the nine sites. There were no statistically significant differences in the number of painful episodes, ED visits, hospital admissions, or surgical interventions. 94 patients from four sites were included in the long-term analysis. There were no statistically significant differences in surgical interventions, painful stone episodes, stone recurrence on imaging, ED visits or hospitalizations for stone-related events between the two groups. Long-term outcomes of dusting versus basketing during ureteroscopy indicate that there are no significant differences in clinical outcomes between the two surgical modalities.

Safety and efficacy of ureteroscopy for urolithiasis in octogenarians

OBJECTIVE

To examine the safety and efficacy of ureteroscopy (URS) for urolithiasis in octogenarians, and identify preoperative risk factors for the incidence of postoperative complications.

METHODS

The patients who underwent URS for urolithiasis were divided into octogenarians and younger patients (age: <80 years), and the groups were compared regarding their clinical characteristics, intraoperative and postoperative complications, and stone-free rate. The predictors of postoperative complications were evaluated using logistic regression models.

RESULTS

A total of 1207 patients were included, 166 in the octogenarian patient group and 1041 in the younger patient group. The proportion of female patients (p < 0.001), American Society of Anesthesiologists (ASA) score (p < 0.001), rate of preoperative pyelonephritis (p < 0.001), and diabetes mellitus (p = 0.003) were higher in the octogenarian group. No statistically significant differences were found between the two groups regarding stone size, location, and intraoperative complications. Postoperative complications, which reached a significant difference, were observed in 34 (20.5%) octogenarians and 117 (11.2%) younger patients (p = 0.002). However, age itself was not significantly associated with postoperative fever, the most frequent postoperative complication, in multivariate analysis. Female sex, ASA score of ≥3, history of diabetes mellitus, and prolonged operative time (≥120 min) were the significant predictors of fever. The stone-free rate in the octogenarian group was superior to that in the younger patient group (80.1% vs. 70.6%, respectively; p = 0.035).

CONCLUSION

Our results suggest that URS for urolithiasis can be safely and effectively applied to octogenarians in selected cases.

International Alliance of Urolithiasis guideline on retrograde intrarenal surgery

OBJECTIVES

To set out the second in a series of guidelines on the treatment of urolithiasis by the International Alliance of Urolithiasis that concerns retrograde intrarenal surgery (RIRS), with the aim of providing a clinical framework for urologists performing RIRS.

MATERIALS AND METHODS

After a comprehensive search of RIRS-related literature published between 1 January 1964 and 1 October 2021 from the PubMed database, systematic review and assessment were performed to inform a series of recommendations, which were graded using modified GRADE methodology. Additionally, quality of evidence was classified using a modification of the Oxford Centre for Evidence-Based Medicine Levels of Evidence system. Finally, related comments were provided.

RESULTS

A total of 36 recommendations were developed and graded that covered the following topics: indications and contraindications; preoperative imaging; preoperative ureteric stenting; preoperative medications; peri-operative antibiotics; management of antithrombotic therapy; anaesthesia; patient positioning; equipment; lithotripsy; exit strategy; and complications.

CONCLUSION

The series of recommendations regarding RIRS, along with the related commentary and supporting documentation, offered here should help provide safe and effective performance of RIRS.

Risk factors for kidney stone disease recurrence: a comprehensive meta-analysis

Background

Kidney stone disease (KSD) is a common illness that causes an economic burden globally. It is easy for patients to relapse once they have suffered from this disease. The reported recurrence rate of KSD ranged from 6.1% to 66.9%. We performed this meta-analysis to identify various potential risk factors for the recurrence of KSD.

Methods

The PubMed, Embase and Web of Science databases were searched using suitable keywords from inception to Mar 2022. A total of 2,663 records were collected initially. After screening the literature according to the inclusion and exclusion criteria, 53 articles (40 retrospective studies; 13 prospective studies) including 488,130 patients were enrolled. The study protocol was registered with PROSPERO (No. CRD42020171771).

Results

The pooled results indicated that 12 risk factors including younger age (n = 18), higher BMI (n = 16), family history of kidney stones (n = 12), personal history of kidney stones (n = 11), hypertension (n = 5), uric acid stone (n = 4), race of Caucasian (n = 3), suspected kidney stone episode before the first confirmed stone episode (n = 3), surgery (n = 3), any concurrent asymptomatic (nonobstructing) stone (n = 2), pelvic or lower pole kidney stone (n = 2), and 24 h urine test completion (n = 2) were identified to be associated with KSD recurrence. In the subgroup analysis, patients with higher BMI (OR = 1.062), personal history of nephrolithiasis (OR = 1.402), or surgery (OR = 3.178) had a higher risk of radiographic KSD recurrence.

Conclusions

We identified 12 risk factors related to the recurrence of KSD. The results of this analysis could serve to construct recurrence prediction models. It could also supply a basis for preventing the recurrence of KSD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-022-01017-4.

Development and validation of a nomogram for risk prediction of nephrolithiasis recurrence in patients with primary hyperparathyroidism

BACKGROUND

Nephrolithiasis is a common complication of primary hyperparathyroidism (PHPT), and the recurrence of nephrolithiasis in patients with PHPT is also an urgent concern. What is worse, there is a scarcity of recommended evaluation to predict the risk of nephrolithiasis recurrence in patients with PHPT. This study was aimed to develop and validate a nomogram to facilitate risk assessment in patients with PHPT.

METHODS

A total of 197 patients with PHPT were retrospectively included in this study from September 2016 to August 2021. Patients' demographic data, blood test parameters, urinalysis, stone parameters, and surgical intervention were collected. Extracted variables were submitted to a least absolute shrinkage and selection operator (LASSO) regression model. A nomogram was built and validated according to the area under the curve (AUC) value, calibration curve, and decision curve analysis.

RESULTS

According to the LASSO regression and logistic regression analyses, five predictors were derived from 22 variables: creatinine, uric acid, bilateral stone, multiplicity, and surgery. The AUC and concordance index of the training cohort and validation cohort were 0.829 and 0.856, and 0.827 and 0.877, respectively. The calibration curve analysis and the decision curve analysis showed that the nomogram had an adequate prediction accuracy.

CONCLUSION

We built a useful nomogram model to predict the risk of nephrolithiasis recurrence in patients with PHPT. This would assist clinicians to provide appropriate advices and managements for these patients.