A Complete World Literature Review of Quality of Life (QOL) in Patients with Kidney Stone Disease (KSD)

Empagliflozin in nondiabetic individuals with calcium and uric acid kidney stones: a randomized phase 2 trial

Efficacy of sodium-glucose cotransporter 2 inhibitors for kidney stone prevention in nondiabetic patients is unknown. In a double-blind, placebo-controlled, single-center, crossover phase 2 trial, 53 adults (≥18 and <75 years) with calcium (n = 28) or uric acid (UA; n = 25) kidney stones (at least one previous kidney stone event) without diabetes (HbA1c < 6.5%, no diabetes treatment) were randomized to once daily empagliflozin 25 mg followed by placebo or reverse (2 weeks per treatment). Randomization and analysis were performed separately for both stone types. Primary analyses were conducted in the per protocol set. Primary outcomes were urine relative supersaturation ratios (RSRs) for calcium oxalate (CaOx), calcium phosphate (CaP) and UA-validated surrogates for stone recurrence. Prespecified RSR reductions (≥15%) were met in both groups of stone formers. In patients with calcium stones, empagliflozin reduced RSR CaP (relative difference to placebo, -36%; 95% confidence interval, -48% to -21%; P < 0.001), but not RSRs CaOx and UA. In patients with UA stones, empagliflozin reduced RSR UA (-30%; 95% confidence interval, -44% to -12%; P = 0.002) but not RSRs CaOx and CaP. No serious or prespecified adverse events occurred. Thus, empagliflozin substantially reduced RSRs in nondiabetic adults with calcium and UA kidney stones. ClinicalTrials.gov registration: NCT04911660 .

The impact of urolithiasis on urology services in a high-prevalence region: A multicenter study

Objective

To assess the effect of upper urinary tract (UUT) urolithiasis on urology services in a region with a high prevalence of the condition, and analyze the trends in endourological procedures for treating UUT urolithiasis and the cost of treatments in 11 hospitals over the last 6 years.

Methods

Using the hospital surgery statistics database, data were gathered from the urology departments of 11 hospitals in Saudi Arabia. The analysis focused on the trends, distribution, and annual cost of endourological procedures for UUT urolithiasis from January 2017 to December 2022.

Results

Out of the total surgery performed (54 711), over half (31 039, 57%) were related to UUT urolithiasis. Extracorporeal shock wave lithotripsy (ESWL) was the most performed procedure among stone-related procedures, accounting for 38% of all procedures. Double-J stent insertion, flexible ureteroscopy (URS), semi-rigid URS, percutaneous nephrolithotomy, and pyelo- and uretero-lithotomy accounted for 25%, 19%, 14%, 3.8%, and 0.35%, respectively. Notably, the number of stone-related UUT procedures in 2022 increased by 35% (from 4671 to 6283) compared to 2017. In the year 2022 compared to 2017, there was a statistically significant increase in the rate of all stone-related UUT procedures (p<0.001), except for ESWL and pyelo- and uretero-lithotomy. The rates of ESWL procedures reduced from 21% in 2017 to 13% in 2022 (p<0.001). Overall, the total cost of treatments has been estimated to be about 192.1 million SAR from 2017 to 2022 with an increase by 107% (47.7 million SAR in 2022 vs. 23.0 million SAR in 2017).

Conclusion

Our research findings suggest that urolithiasis poses a significant burden, accounting for over half of all urological surgery performed at the participating centers. Furthermore, there has been a 35% rise in stone-related UUT procedures over the past 6 years. Percutaneous nephrolithotomy, flexible URS, and semi-rigid URS have experienced significant increase in usage. Furthermore, in 2022 the cost of urolithiasis treatments has been more than doubled compared to 2017.

Risk Factors of Asymptomatic Kidney Stone Passage in Adults with Recurrent Kidney Stones

Key Points

Asymptomatic stone passage was common in patients with recurrent calcium-containing kidney stones. Higher the number of stones at presentation, more likely it was that a kidney stone would spontaneously pass over time without causing any symptoms.

Background

Kidney stones are a common health problem and are characterized by a high risk of recurrence. A certain number of kidney stones pass asymptomatically. Data regarding the frequency of asymptomatic spontaneous stone passages are limited.

Methods

To assess the frequency of asymptomatic spontaneous stone passage and its covariates, we conducted a post hoc analysis of the prospective randomized NOSTONE trial. All asymptomatic spontaneous stone passages were identified by comparing the total number of kidney stones on low-dose noncontrast computed tomography (CT) imaging at the beginning and end of the study, considering symptomatic stone passages and surgical stone removal. The statistical analysis focused on the association of independent variables and the number of asymptomatic spontaneous stone passages using linear regression analyses.

Results

Of the 416 randomized patients, 383 with both baseline and end-of-study CT were included in this analysis. The median follow-up period was 35 months, the median patient age was 49 years (interquartile range [IQR], 40–55), and 20% of the patients were female. A total of 442 stone events occurred in 209 of 383 (55%) patients: 217 of 442 (49%) were symptomatic spontaneous stone passages, 67 of 442 (15%) were surgically removed stones, and 158 of 442 (36%) were asymptomatic spontaneous stone passages. The median size of asymptomatic stones (2.4 mm; IQR, 1.95–3.4) and the size of symptomatic stones (2.15 mm; IQR, 1.68–2.79) that passed spontaneously were not significantly different (P = 0.37). The number of asymptomatic spontaneous stone passages was significantly associated with a higher number of stones on CT at randomization (P = 0.001). Limitations include the lack of data on stone size at the time of passage and overrepresentation of White men.

Conclusions

Asymptomatic stone passage was common in patients with recurrent calcium-containing kidney stones. The higher the number of stones at presentation, the more likely it was that a kidney stone would spontaneously pass over time without causing any symptoms.

Clinical Trial registry name and registration number:

NOSTONE trial and: NCT03057431 .

Prevalence and characteristics of genetic disease in adult kidney stone formers

BACKGROUND

Molecular mechanisms of kidney stone formation remain unknown in most patients. Previous studies have shown a high heritability of nephrolithiasis, but data on the prevalence and characteristics of genetic disease in unselected adults with nephrolithiasis are lacking. This study was conducted to fill this important knowledge gap.

METHODS

We performed whole exome sequencing in 787 participants in the Bern Kidney Stone Registry, an unselected cohort of adults with one or more past kidney stone episodes [kidney stone formers (KSFs)] and 114 non-kidney stone formers (NKSFs). An exome-based panel of 34 established nephrolithiasis genes was analysed and variants assessed according to American College of Medical Genetics and Genomics criteria. Pathogenic (P) or likely pathogenic (LP) variants were considered diagnostic.

RESULTS

The mean age of KSFs was 47 ± 15 years and 18% were first-time KSFs. A Mendelian kidney stone disease was present in 2.9% (23/787) of KSFs. The most common genetic diagnoses were cystinuria (SLC3A1, SLC7A9; n = 13), vitamin D-24 hydroxylase deficiency (CYP24A1; n = 5) and primary hyperoxaluria (AGXT, GRHPR, HOGA1; n = 3). Of the KSFs, 8.1% (64/787) were monoallelic for LP/P variants predisposing to nephrolithiasis, most frequently in SLC34A1/A3 or SLC9A3R1 (n = 37), CLDN16 (n = 8) and CYP24A1 (n = 8). KSFs with Mendelian disease had a lower age at the first stone event (30 ± 14 versus 36 ± 14 years; P = .003), were more likely to have cystine stones (23.4% versus 1.4%) and less likely to have calcium oxalate monohydrates stones (31.9% versus 52.5%) compared with KSFs without a genetic diagnosis. The phenotype of KSFs with variants predisposing to nephrolithiasis was subtle and showed significant overlap with KSFs without diagnostic variants. In NKSFs, no Mendelian disease was detected and LP/P variants were significantly less prevalent compared with KSFs (1.8% versus 8.1%).

CONCLUSION

Mendelian disease is uncommon in unselected adult KSFs, yet variants predisposing to nephrolithiasis are significantly enriched in adult KSFs.

Association of health-related quality of life with urinary tract infection among kidney stone formers

Kidney stones and infections significantly affect patients' health-related quality of life (HRQOL); however, the relationship between urinary tract infections (UTIs) and HRQOL in patients with kidney stones remains unclear. This study aimed to investigate the relationship using the validated Chinese version of the Wisconsin Stone Quality of Life questionnaire (C-WISQOL). We prospectively recruited 307 patients with kidney stones to complete the C-WISQOL before and after stone removal. The participants were diagnosed with UTI based on the presence of pyuria or bacteriuria with or without clinical symptoms. The psychometric properties of the C-WISQOL were statistically analyzed. Multivariate linear regression was used to predict the risk factors for impaired HRQOL in patients with stones and UTIs. The questionnaire is a reliable and robust tool for evaluating HRQOL in Chinese-speaking patients with urolithiasis. The UTI and kidney stone co-occurrence was significantly associated with female sex, diabetes mellitus, more previous stone events, higher antibiotic usage, positive stone- or UTI-related symptoms, and postoperative residual stones. The preoperative C-WISQOL scores and improvement in the HRQOL after stone removal in patients clinically diagnosed with UTI were significantly inferior to those in patients without UTI. The regression analyses showed that worse HRQOL was predicted by more previous stone events and positive stone- or UTI-related symptoms. In contrast, the presence of diabetes mellitus and postoperative residual stone fragments predicted a lower improvement in the HRQOL. These findings underscore UTI's harmful impact on perioperative HRQOL in patients with kidney stones and could help strategies benefit those patients.

Thiazides for kidney stone recurrence prevention

PURPOSE OF REVIEW

Kidney stones are the most common condition affecting the kidney, and characterized by a high rate of recurrence. Thiazide and thiazide-like diuretics (thiazides) are commonly prescribed to prevent the recurrence of kidney stones. This review offers a comprehensive up-to-date assessment of the evidence supporting the use of thiazides for kidney stone recurrence prevention, highlights potential harms associated with treatment, and identifies areas of knowledge that require further investigation.

RECENT FINDINGS

The clinical routine to prescribe thiazides for kidney stone prevention has recently been challenged by the findings of the large NOSTONE trial that failed to show superiority of hydrochlorothiazide at doses up to 50 mg daily over placebo in preventing a composite of clinical or radiological recurrence in patients at high risk of recurrence. Yet, adverse events such as new onset diabetes mellitus and gout were more common in patients receiving hydrochlorothiazide compared to placebo. As demonstrated by a novel meta-analysis presented in this review encompassing all randomized placebo-controlled trials with thiazide monotherapy, current trial evidence does not indicate that thiazide monotherapy is significantly better than placebo in preventing kidney stone recurrence.

SUMMARY

Given the limited efficacy and possible adverse effects, we advocate for a restrictive use of thiazides for kidney stone recurrence prevention. Clearly, there remains a high unmet medical need for effective, targeted therapies to prevent recurrence of kidney stones.

The impact of kidney stone disease on quality of life in high-risk stone formers

OBJECTIVE

To assess the impact of kidney stone disease (KSD) and its treatment on the health-related quality of life (HRQOL) of high-risk stone formers with hyperparathyroidism, renal tubular acidosis, malabsorptive disease, and medullary sponge kidney.

PATIENTS AND METHODS

The Wisconsin Stone Quality of Life questionnaire was used to evaluate HRQOL in 3301 patients with a history of KSD from 16 institutions in North America between 2014 and 2020. Baseline characteristics and medical history were collected from patients, while active KSD was confirmed through radiological imaging. The high-risk group was compared to the remaining patients (control group) using the Wilcoxon rank-sum test.

RESULTS

Of 1499 patients with active KSD included in the study, the high-risk group included 120 patients. The high-risk group had significantly lower HRQOL scores compared to the control group (P < 0.01). In the multivariable analyses, medullary sponge kidney disease and renal tubular acidosis were independent predictors of poorer HRQOL, while alkali therapy was an independent predictor of better HRQOL (all P < 0.01).

CONCLUSIONS

Among patients with active KSD, high-risk stone formers had impaired HRQOL with medullary sponge kidney disease and renal tubular acidosis being independent predictors of poorer HRQOL. Clinicians should seek to identify these patients earlier as they would benefit from prompt treatment and prevention.

[Prevention of recurrence of urolithiasis]

Urolithiasis is one of the most frequent urological diseases. Identifying the causes of stone formation forms the basis for successful prevention of recurrence. Metabolic diagnostics and measures for prevention of recurrence are based on the assignment of the patient to a low-risk or high-risk group. Analysis of the urinary calculi is an essential prerequisite for identifying patients at risk. The general recommendations on diet and lifestyle are considered to be the basis of treatment. Depending on the type of stone and the individual biochemical risk profile of a patient, these general measures should be supplemented by targeted medical nutrition therapy and pharmacological treatment. Mixed stones can pose a challenge for the treatment and prevention of recurrence. A personalized treatment decision that takes the various components of mixed stones into account could further improve the prevention of recurrence of urolithiasis.

Measuring quality of life in patients with kidney stone disease: is it the future in endourology?

PURPOSE OF REVIEW

Kidney stone disease is recognized to negatively impact quality of life. This pertains to acute episodes, surgical interventions and even during asymptomatic periods. Over time there has been increased attention towards assessing this subjective parameter, including as a determinant of treatment success. Our aim was to evaluate the current status and emerging trends in this field.

RECENT FINDINGS

Patient groups most affected appear to be recurrent stone formers, cystine stone formers, women, younger populations, non-Caucasians and low-income populations. Several stone specific patient reported outcome measures are now available of which, WISQol has been implemented the most in clinical research studies. More invasive interventions such as percutaneous nephrolithotomy impede quality of life to greater extent than alternatives such as shockwave lithotripsy.

SUMMARY

There are certain patient groups who are more vulnerable to the negative impact of kidney stone disease on their quality of life. Urologists can improve patient care by recognizing these particular populations as well as by implemented patient reported outcome measures in their routine clinical practice and when performing research.

Mixed stones: urinary stone composition, frequency and distribution by gender and age

Proper analysis of urinary stone composition is a cornerstone for diagnosis, targeted treatment and recurrence prevention of urolithiasis. The aim of this study was to determine the composition, frequency and distribution of mixed stones according to gender and age of patients. A total of 42,519 urinary stones from 30,311 men and 12,208 women submitted between January 2007 and December 2020 were studied. Most urinary calculi consisted of two components (50.9%), followed by stones of a single constituent (27.1%) and three-component stones (21.9%), while four-component stones were only rarely identified (0.1%). Among all stones, 49.8% consisted of whewellite (COM), weddellite (COD), and mixtures of COM and COD, 33.8% were pure carbonate apatite (CA) and mixtures of CA with COM and/or COD, while 7.6% were composed of uric acid anhydrous (UAA), uric acid dihydrate (UAD), and mixed UAA and UAD. The remaining 8.8% of calculi were rare single-component stones and rare mixtures of various constituents. The number of stone components was inversely associated with age (p < 0.001). The proportion of men decreased significantly with the number of stone constituents, from 3.01:1 for single-component stones to 1.0:1 for four-component urinary calculi (p < 0.001). The vast majority of urinary calculi consisted of two or more components in varying proportions. While age was inversely associated with the number of stone constituents, the proportion of women increased significantly from single-component to four-component urinary calculi. A significant proportion of mixed stones could present a challenge for diagnosis and targeted recurrence prevention.

Ureteroscopy Versus Double J Stenting in Emergency Treatment of Obstructive Lithiasis

Objective: Ureteroscopy (URS) is a commonly used procedure for the management of ureteral stones. While elective URS has been extensively studied, the literature on emergency URS remains limited. The aim of the present study is to evaluate the efficacy and safeness of URS performed in emergency settings and to determine the ideal candidates for this type of intervention. Methods:Patients who underwent URS for ureteral stones in a single healthcare unit, "Saint John" Emergency Clinical Hospital, Bucharest, Romania, were included in a retrospective investigation between April 2022 and March 2023. The study group was divided into two subgroups: group A (138 patients who underwent semirigid URS in an emergency setting) which was subdivided into group A1 (95 patients with stone on the distal ureter) and group A2 (43 patients with stone on the proximal ureter), and group B (151 patients who underwent a double J stent insertion). The success rate defined as stone fragmentation and resolution of renal obstruction, along with intraoperative and postoperative complications were assessed. A URS procedure was considered unsuccessful if either the instrument could not be passed to access the stone or it was deemed unsafe to perform the URS. In such cases, patients were managed by inserting a ureteric stent and scheduled for a subsequent procedure. Results:It could be observed that most complications occurred in emergency ureteroscopy on distal ureter (95 cases) and the most severe ones on proximal ureter (two cases - Clavien 4). Double J stenting provided a reduced number of complications (51 cases). It should be mentioned that patients with emergency semirigid ureteroscopy had more complications than those with double J stent for every group of BMI, while most of the complications were observed in the groups with the highest BMI. The success of the URS procedure was determined based on complete stone fragmentation and extraction, and it was of 91.3% for cases with emergency ureteroscopy. Conclusion:Patients who underwent URS for ureteral stones at a single facility, "Saint John" Emergency Clinical Hospital, Bucharest, Romania, were included in a retrospective investigation. The success rates and complication rates of emergency URS were comparable to those of elective URS, providing valuable insights for clinical decision-making.

Quality of life after urinary stone surgery based on Japanese Wisconsin Stone Quality of Life questionnaire: multicenter analysis from SMART study group

We aimed to evaluate the impact of surgical treatment for urinary stones on perioperative health-related quality of life (HRQOL) using the Japanese Wisconsin Stone Quality of Life questionnaire (J-WISQOL), an HRQOL measure designed for patients with urinary stones. This study prospectively enrolled 123 patients with urinary stones who visited three academic hospitals for stone treatment. The participants completed the J-WISQOL within 4 weeks before and after the urinary stone treatment. Treatments included shock wave lithotripsy (SWL), ureteroscopy lithotripsy, and endoscopic combined intrarenal surgery. J-WISQOL was assessed for age, stone size and location, type of treatment, stone-free status, postoperative ureteral stent placement, hospital stay, and complications in all patients. Patients with stones in the ureter had significantly greater social impact D1 and disease impact D3 than those with stones in the kidney. In a comparison of pre- and postoperative J-WISQOL, patients without postoperative ureteral stent placement scored significantly higher on social impact D1 and disease impact D3. Patients with shorter hospital stays had significantly higher social impact D1 and disease impact D3 (p < 0.001) than those with longer hospital stays. SWL significantly improved the total score, social impact D1, and disease impact D3 compared with other treatments. Perioperative HRQOL in patients with urinary stones is particularly affected by the type of treatment, ureteral stent placement, and hospital stay, which should be considered in surgical selection and patient decision-making.

Neuroendocrine Parathyroid Tumors: Quality of Life in Patients with Primary Hyperparathyroidism

Tumors of the parathyroid glands, when associated with PTH (parathyroid hormone) excess, display a large area of complications; in addition to the classical clinical picture of primary hyperparathyroidism (PHP), a complex panel of other symptoms/signs can be identified, including memory and cognitive impairment, chronic asthenia/fatigue, reduced muscle functionality, depressive mood, non-specific bone pain, and loss of sleep quality. The perception of quality of life (QoL) can be supplementarily enhanced by their progressive onset, which makes many patients not be fully aware of them. Their improvement was reported very early after parathyroidectomy (PTx), yet the level of statistical evidence does not qualify these non-classical elements as standalone indications for PTx. Our objective is introducing an up-to-date on QoL scores with regards to the patients diagnosed with PHP, particularly taking into consideration PHP management from baseline to post-operatory outcome, including in cases with multiple endocrine neoplasia. This is a narrative review of literature. We revised full-length papers published in English through PubMed research conducted between January 2018 and May 2023 by using the key words "quality of life" and "primary hyperparathyroidism". We particularly looked at data on self-reported QoL (through questionnaires). We excluded from the search the studies focused on non-PTH related hypercalcemia, secondary, and/or renal/tertiary hyperparathyroidism, and vitamin D supplementation. Overall, we identified 76 papers and selected for the final analysis 16 original studies on QoL and PHP (a total of 1327 subjects diagnosed with syndromic and non-syndromic PHP). The studies with the largest number of individuals were of 92, 104, 110, 134, 159, as well as 191. A few cohorts (n = 5) were of small size (between 20 and 40 patients in each of them). Concerning the study design, except for 2 papers, all the mentioned studies provided longitudinal information, particularly the timeframe from baseline (before PTx) and after surgery. The post-operatory follow-up was of 3-6 months, but mostly between 1 and 3 years (maximum a decade of surveillance). The age of the patients varies between medians of 56, 62, 64, and 68 years. Most frequent questionnaires were SF-36, PHPQoL, and PAS. Despite not being unanimously similar, an overall reduced score of QoL in patients with PHP versus controls was registered, as well as general improvement following PTx. Variations of QoL results might have a multifactorial background from different comorbidities, studied populations, technical aspects of collecting the data, etc. QoL scores in PHP represents a complex heterogeneous picture, from their correlation with clinical features and lab assays (e.g., the level of serum calcium), the associated comorbidities (such as multiple endocrine neoplasia syndromes), up to the assessment of the QoL improvement after parathyroidectomy (PTx). While current studies do not unanimously agree on each QoL domain, the assessment of QoL might represent a supplementary argument to consider when deciding for PTx, especially in asymptomatic cases and in patients who do not fit into well-known categories of surgery candidates, according to current guidelines, thus assessing QoL in PHP is part of a current research gap. QoL evaluation in PHP remains an open issue, towards which awareness should be cultivated by both endocrinologists and surgeons. The introduction of a routine evaluation of the QoL scores in patients, as well as the selection of the most appropriate questionnaire(s), represents an open chapter thus awareness in mandatory.

Development and Preliminary Validation of the 6-Item Short Form of the Wisconsin Stone Quality of Life Questionnaire

OBJECTIVE

To develop a short form of the Wisconsin Stone Quality of Life (WISQOL): 1) identify the smallest subset of items from WSIQOL that accurately predict patients' health-related quality of life (HRQOL), and 2) in a clinical patient population, test these items-grouped together to form the WISQOL-short form (SF) - and assess its convergent validity.

MATERIALS AND METHODS

The items for the WISQOL-SF were identified based on classic item analysis theory. Patients who previously completed the original 28-item WISQOL were randomly split into 2 groups of equal size. Scores for the WISQOL were calculated for one group while those for the WISQOL-SF were calculated for the other. Cronbach's alpha coefficients were calculated. Impacts of demographic and clinical factors as well as stone and symptom status at the time of WISQOL completion were examined.

RESULTS

Patients (n = 740) who completed the WISQOL between 6/2017 and 11/2021 were included. Patients were 48% male, 54.1 ± 14.6 years old, and had a BMI of 31.2 ± 8.1. After item analysis and reduction, the six items ultimately included in the WISQOL-SF represented 2 of the 4 domains (social and emotional) of the original WISQOL. The internal consistency of the WISQOL-SF was similar to the original (Cronbach's alpha 0.943 vs. 0.973). No differences for health-related quality of life were found between groups (P = .567).

CONCLUSION

The WISQOL-SF demonstrated the expected differences for gender and between patients with and without stone-related symptoms at the time of WISQOL completion. The WISQOL-SF showed good consistency and produced similar HRQOL scores to the full-form WISQOL.

Hydrochlorothiazide and Prevention of Kidney-Stone Recurrence

BACKGROUND

Nephrolithiasis is one of the most common conditions affecting the kidney and is characterized by a high risk of recurrence. Thiazide diuretic agents are widely used for prevention of the recurrence of kidney stones, but data regarding the efficacy of such agents as compared with placebo are limited. Furthermore, dose-response data are also limited.

METHODS

In this double-blind trial, we randomly assigned patients with recurrent calcium-containing kidney stones to receive hydrochlorothiazide at a dose of 12.5 mg, 25 mg, or 50 mg once daily or placebo once daily. The main objective was to investigate the dose-response effect for the primary end point, a composite of symptomatic or radiologic recurrence of kidney stones. Radiologic recurrence was defined as the appearance of new stones on imaging or the enlargement of preexisting stones that had been observed on the baseline image. Safety was also assessed.

RESULTS

In all, 416 patients underwent randomization and were followed for a median of 2.9 years. A primary end-point event occurred in 60 of 102 patients (59%) in the placebo group, in 62 of 105 patients (59%) in the 12.5-mg hydrochlorothiazide group (rate ratio vs. placebo, 1.33; 95% confidence interval [CI], 0.92 to 1.93), in 61 of 108 patients (56%) in the 25-mg group (rate ratio, 1.24; 95% CI, 0.86 to 1.79), and in 49 of 101 patients (49%) in the 50-mg group (rate ratio, 0.92; 95% CI, 0.63 to 1.36). There was no relation between the hydrochlorothiazide dose and the occurrence of a primary end-point event (P = 0.66). Hypokalemia, gout, new-onset diabetes mellitus, skin allergy, and a plasma creatinine level exceeding 150% of the baseline level were more common among patients who received hydrochlorothiazide than among those who received placebo.

CONCLUSIONS

Among patients with recurrent kidney stones, the incidence of recurrence did not appear to differ substantially among patients receiving hydrochlorothiazide once daily at a dose of 12.5 mg, 25 mg, or 50 mg or placebo once daily. (Funded by the Swiss National Science Foundation and Inselspital; NOSTONE ClinicalTrials.gov number, NCT03057431.).

Quality of life of patients treated for kidney stones 10-20mm in diameter in terms of the type of operation performed: A qualitative study

INTRODUCTION

Urolithiasis is a common chronic disease whose effect on patients' quality of life (QOL) is considerable but depends on the treatment received, differing between types of surgery. Intrarenal stones can be treated with different techniques: extracorporeal shock wave lithotripsy (ESWL), flexible ureteroscopy (fURS), and mini percutaneous nephrolithotomy (mini-PCNL), with proportional success and complication rates. The aim of this study was to qualitatively explore the impact of the different techniques on patients' QOL and understand their experiences of treatment choices.

METHODS

Patients treated for medium-sized kidney stones (10-20mm in diameter) were interviewed in a semi-structured manner. The interview data were transcribed and analyzed by theme according to consolidated criteria for reporting qualitative research (COREQ) guidelines.

RESULTS

Data saturation was achieved after interviewing 15 patients. The mean interview time was 34min (standard deviation (SD), 6.8min). The mean patient age was 54 years (SD, 9.5 years). Eight patients underwent ESWL, 10 were treated with fURS, and 8 underwent mini-PCNL. Twenty-seven subthemes were coded and regrouped into eight major themes, namely: no sense of choice in the decision-making process for eleven patients; extremely negative experiences of double-J stents for fourteen patients; concern about the risk of recurrence or treatment failure for thirteen patients; complicated hygiene and dietary recommendations for nine patients; technique-dependent postoperative outcomes; relatively well-tolerated operations for thirteen patients; a poor experience of sick leave, often because of a double-J stent; different views regarding future operations. In fact, a third of patients would choose the most effective treatment, a third would choose the simplest procedure and the last third would trust their urologist. Patients' experiences of these operations are variable.

CONCLUSION

Urologists must support their patients by presenting the different treatment options with clear, appropriate, and unbiased information. This should ensure patients take part in treatment decisions as part of a personalized treatment plan.

LEVEL OF EVIDENCE: 3

Cost-utility analysis of shockwave lithotripsy vs ureteroscopic stone treatment in adults

OBJECTIVES

To assess the cost-effectiveness, resource use implications, quality-adjusted life-years (QALYs) and cost per QALY of care pathways starting with either extracorporeal shockwave lithotripsy (SWL) or with ureteroscopic retrieval (ureteroscopy [URS]) for the management of ureteric stones.

PATIENTS AND METHODS

Data on quality of life and resource use for 613 patients, collected prospectively in the Therapeutic Interventions for Stones of the Ureter (TISU) randomized controlled trial (ISRCTN 92289221), were used to assess the cost-effectiveness of two care pathways, SWL and URS. A health provider (UK National Health Service) perspective was adopted to estimate the costs of the interventions and subsequent resource use. Quality-of-life data were calculated using a generic instrument, the EuroQol EQ-5D-3L. Results are expressed as incremental cost-effectiveness ratios and cost-effectiveness acceptability curves.

RESULTS

The mean QALY difference (SWL vs URS) was -0.021 (95% confidence interval [CI] -0.033 to -0.010) and the mean cost difference was -£809 (95% CI -£1061 to -£551). The QALY difference translated into approximately 10 more healthy days over the 6-month period for the patients on the URS care pathway. The probabaility that SWL is cost-effective is 79% at a society's willingness to pay (WTP) threshold for 1 QALY of £30,000 and 98% at a WTP threshold of £20,000.

CONCLUSION

The SWL pathway results in lower QALYs than URS but costs less. The incremental cost per QALY is £39 118 cost saving per QALY lost, with a 79% probability that SWL would be considered cost-effective at a WTP threshold for 1 QALY of £30 000 and 98% at a WTP threshold of £20 000. Decision-makers need to determine if costs saved justify the loss in QALYs.

Patient-reported outcome measures (PROMs) in stone surgery: A multi-centre study of patient experience of flexible ureteroscopy (fURS) versus extracorporeal shockwave lithotripsy (SWL)

Objectives:

To compare patient-reported outcome measures (PROMs) for patients with symptomatic renal stone disease treated by flexible ureterorenoscopy (fURS) and shockwave lithotripsy (SWL)

Introduction:

Historically, surgical outcomes are measured by surgeon-specific outcomes such as ‘stone-free rates’. More recently, there is increasing emphasis on PROMs to ascertain a patient’s perspective of their own surgical outcome. Despite this, the literature in reference to renal stone-specific PROMs following stone treatment remains limited.

Methods:

Data were collected in a prospective multi-centre study. Patients undergoing fURS or SWL were asked to complete the validated Cambridge Renal Stone Patient Reported Outcome Measure ( CReSP) on the day of initial treatment and at weeks 1, 6 and 12 post-operatively.

Results:

Data were collected for 119 patients. Three were excluded as stone metric and demographic details were incomplete. Sixty underwent SWL and 56 underwent fURS. Median stone size was 7.52 mm. There were no significant differences in baseline PROM scores between the treatment groups. At 1 week, the PROM scores were significantly higher in the fURS group compared to SWL (27.40 ± 0.85sd versus 22.51 ± 1.07sd; p < 0.05). However, at 6 and 12 weeks, the PROM scores were significantly lower in the fURS group (18.51 ± 2.27sd versus 23.67 ± 1.30sd; p < 0.05) and (17.01 ± 2.29sd versus 22.49 ± 1.49sd; p < 0.05), respectively. By week 12, overall scores for anxiety and social factors were more favourable in the fURS cohort.

Conclusion:

Our study suggests that fURS is associated with a short-lived increase in morbidity in comparison with SWL, which may be due to ureteric stenting in the majority of patients post-operatively. However, fURS patients appear to report significantly better PROM scores in the longer term. This appears to be associated with more favourable anxiety and social factor scoring over the treatment period.

Level of evidence:

Not applicable.

Changes in Urine Composition and Risk of Kidney Stone Disease Following Bariatric Surgery: A Systematic Review over Last 2 Decades

PURPOSE OF REVIEW

The association of kidney stone disease (KSD) and gastrointestinal (GI) surgery has been well established. With a rising obesity crisis, we wanted to see the correlation of urinary composition in patients undergoing bariatric surgery and their risk of KSD. The objective of this paper is to perform a systematic review and meta-analysis of literature to evaluate the changes in urinary composition and risk of KSD following bariatric surgery.

RECENT FINDINGS

A total of seven studies (2498 patients) underwent bariatric surgery with a mean age of 46.7 years and a male:female ratio of 1:3. The most popular bariatric surgery was the Roux-en-Y procedure. Meta-analysis of the studies showed that significant decrease in urinary calcium, citrate, and urate, and increase in urinary oxalate. There was also a nonsignificant volume reduction in the post-operative cohort. The decrease in urinary citrate and increase in urinary oxalate are both predisposing factors of stone formation. There is strong evidence that bariatric surgery results in significant changes in urine composition in keeping with the increased risk of developing KSD. This identifies useful therapeutic targets in the prophylactic management of patients who have undergone bariatric surgery.

[Urolithiasis-Therapy and recurrence prevention taking into account gender-specific aspects]

The prevalence of urolithiasis is steadily increasing worldwide in both genders. Diet and lifestyle, such as the rising prevalence of obesity and other metabolic syndrome traits, are considered key factors in this trend. Gender differences as a result of interventional therapy for urolithiasis have not been observed. However, iatrogenic injury to the male urethra is considered the most common reason for urethral strictures after endourologic (stone) therapy. In contrast, sepsis, as the major cause of urinary stone-related mortality, is more frequently reported in women after ureterorenoscopy and percutaneous nephrolithotomy. There are also differences in the frequency of various types of stones between men and women. Calcium oxalate and uric acid stones are more commonly observed in men, while carbonate apatite and struvite are diagnosed more often in women. Urinary stone analysis is therefore paramount for successful recurrence prevention. Diagnosis is based on the assignment of patients to the low-risk or high-risk group. The medical nutrition and pharmacological measures for the therapy of the respective type of stone are based on the risk factors in 24 h urine samples. A personalized approach that accounts for gender differences could further improve treatment, and recurrence prevention decisions for urinary stones.

Current status of nomograms and scoring systems in paediatric endourology: A systematic review of literature

INTRODUCTION

The incidence of paediatric kidney stone disease is increasing worldwide, with the requirement for endourological interventions mirroring this. Multiple nomograms, grading tools and scoring systems now exist in the adult setting, which aim to enhance the pre-operative planning and decision-making associated with these surgeries. In recent years, there has been increasing interest in nomograms dedicated for use in the paediatric setting. This study provides an up-to-date review and assessment of available paediatric endourology nomograms and scoring systems.

METHODS

A comprehensive search of worldwide literature was conducted according PRISMA methodology. Studies describing paediatric-specific endourology nomograms, scoring systems or grading tools and studies externally validating these tools, or existing adult tools in a paediatric population, were evaluated and included in the narrative data synthesis.

RESULTS

A total of 7 endourology nomograms were identified. 4 were paediatric-specific, 2 for shockwave lithotripsy, 1 for percutaneous nephrolithotomy or ureteroscopy and 1 for percutaneous nephrolithotomy specifically. Only the 2 shockwave lithotripsy nomograms have been externally validated in 4 further studies and showed efficacy in predicting treatment success. 3 adult tools, all specific to PCNL have been investigated and validated in a paediatric setting in 11 studies. In general, they showed efficacy in the prediction of stone free rate but were poor at predicting likelihood of complications.

CONCLUSION

A limited number of paediatric-specific endourology predictive nomograms are available to aid in the management of kidney stone disease, with the strongest evidence supporting those designed for shockwave lithotripsy. Although 3 adult tools have been implemented, there are problems applying these to the paediatric setting and further development of paediatric-specific tools is necessary.

Comparison between standard, mini and ultra-mini percutaneous nephrolithotomy for single renal stones: a prospective study

PURPOSE

Based on the current trend of miniaturization of instruments used in percutaneous nephrolithotomy (PCNL), it is necessary to compare different PCNL modalities regarding their access sheath size used. Thus, the safety and efficacy among standard, mini and ultra-mini PCNL (s-PCNL, m-PCNL, um-PCNL) were compared.

METHODS

We performed a prospective, non-randomized trial between January 2018 and July 2020. Patients with stones classified as Guy's stone score grade I were included. The set-up for s-PCNL and m-PCNL included a 30 Fr and 22 Fr percutaneous tract, respectively. In both set-ups, an ultrasonic/ballistic lithotripter was utilized. In the case of um-PCNL, a 12 Fr percutaneous tract was established. A high-power laser was used for lithotripsy. Hemoglobin drop, complication rate, length of hospital stay (LOS), stone-free rate (SFR) and operation time were evaluated.

RESULTS

A total of 84 patients, 28 patients per method, were evaluated. Hemoglobin drop was higher in the s-PCNL group when compared to m-PCNL (p = 0.008) and um-PCNL groups (p < 0.001), while um-PCNL group had the slightest hemoglobin drop. LOS was similar between s-PCNL group and m-PCNL group, but um-PCNL group required shorter hospital stay than the other two modalities (p < 0.001). The complication and transfusion rates as well as SFR did not differ between groups. Operation time in the um-PCNL set-up was longer compared to s-PCNL (p < 0.001) and m-PCNL (p = 0.011), whereas s-PCNL and m-PCNL did not differ significantly.

CONCLUSION

m-PCNL showed less hemoglobin drop, but similar operation time and SFR when compared to s-PCNL. um-PCNL showed even less hemoglobin drop, but the operation time was longer compared to the two other modalities.

Lithotripsy devices for percutaneous nephrolithotomy (PNL) - new developments

PURPOSE OF REVIEW

Percutaneous nephrolithotomy (PNL) is the mainstay of surgery for renal calculi>2 cm or complex multiple calculi and is a technique that has been around since 1976. We review recent literature surrounding novel lithotripsy devices and technology used in PNL.

RECENT FINDINGS

At present, the Holmium:yttrium-aluminum-garnet (Ho:YAG) laser is widely accepted as the gold standard laser lithotripsy for PNL. SwissLithoClast Trilogy offers a range of probes with a trifecta of electromagnetic, ultrasonic energy with surgeon-controlled suction. The Olympus Shockpulse-SE is a similar lithotripter that relies on continuous ultrasonic energy with pulsed ballistic energy to break stones. Thulium Fiber Laser (TFL) offers an alternative laser energy source to the Holmium laser, which has been shown to be very effective at producing small stone fragments and dust. The Moses technology is another addition in a long list of improvements to the Ho:YAG laser, forming vaporization bubble through which more effective energy can be applied to stones.

SUMMARY

Trilogy, Shockpulse, TFL and Moses pulse modulation technology for the Holmium laser all provide improvements compared with older lithotripsy devices. In particular, they convey a safer, efficient and more effective way to manage and clear stones.

SIMULTANEOUS BILATERAL ENDOSCOPIC SURGERY (SBES): IS IT READY FOR PRIME TIME?

Introduction To date, some data available in literature on simultaneous bilateral endoscopic surgery (SBES) have shown good outcomes in terms of both effectiveness and safety. The aim of this study was to report the outcomes pertaining to the effectiveness and safety of SBES performed in our series of patients with bilateral renal stones. Materials and Methods A prospective analysis of consecutive patients who underwent SBES for bilateral renal stones at our institution between June 2017 and September 2021 was performed. Routine preoperative and 1-month postoperative work-up included history, physical examination, urinalysis, urine culture, and blood tests, including the evaluation of estimated glomerular filtration rate (eGFR) using the Cockcroft-Gault equation. An abdominal non-contrast computerized tomography (NCCT) scan was performed in all cases preoperatively and 1-month postoperatively. Peri/postoperative complications were reported according to the Clavien-Dindo classification system. The primary endpoint of the study was stone-free rate (SFR), and the secondary endpoints were Clavien-Dindo complications grade 1 or higher. Results Altogether, 101 patients met the inclusion criteria and were enrolled in the study. SFR for all renal units was achieved in 82 patients (81.1%) at the 1-month follow-up. Twelve patients underwent additional flexible ureteroscopy for residual fragments, and seven asymptomatic patients with single small residual fragment were observed. Eighteen patients (17.8%) experienced Clavien-Dindo Grade I-II complications, whereas one patient (1%) experienced Clavien-Dindo Grade IIIa complication (renal arteriovenous fistula embolization under local anesthesia). Conclusions SBES is a safe and effective procedure for the treatment of bilateral renal stones. Further randomized studies with larger populations are needed to confirm these favorable outcomes of SBES to establish it as an alternative to staged surgeries in patients with bilateral renal stones. Appropriate patient selection is of paramount importance for achieving good outcomes without experiencing severe complications.

Shockwave lithotripsy compared with ureteroscopic stone treatment for adults with ureteric stones: the TISU non-inferiority RCT

BACKGROUND

Urinary stone disease affects 2-3% of the general population. Ureteric stones are associated with severe pain and can have a significant impact on a patient's quality of life. Most ureteric stones are expected to pass spontaneously with supportive care; however, between one-fifth and one-third of patients require an active intervention. The two standard interventions are shockwave lithotripsy and ureteroscopic stone treatment. Both treatments are effective, but they differ in terms of invasiveness, anaesthetic requirement, treatment setting, number of procedures, complications, patient-reported outcomes and cost. There is uncertainty around which is the more clinically effective and cost-effective treatment.

OBJECTIVES

To determine if shockwave lithotripsy is clinically effective and cost-effective compared with ureteroscopic stone treatment in adults with ureteric stones who are judged to require active intervention.

DESIGN

A pragmatic, multicentre, non-inferiority, randomised controlled trial of shockwave lithotripsy as a first-line treatment option compared with primary ureteroscopic stone treatment for ureteric stones.

SETTING

Urology departments in 25 NHS hospitals in the UK.

PARTICIPANTS

Adults aged ≥ 16 years presenting with a single ureteric stone in any segment of the ureter, confirmed by computerised tomography, who were able to undergo either shockwave lithotripsy or ureteroscopic stone treatment and to complete trial procedures.

INTERVENTION

Eligible participants were randomised 1 : 1 to shockwave lithotripsy (up to two sessions) or ureteroscopic stone treatment.

MAIN OUTCOME MEASURES

The primary clinical outcome measure was resolution of the stone episode (stone clearance), which was operationally defined as 'no further intervention required to facilitate stone clearance' up to 6 months from randomisation. This was determined from 8-week and 6-month case report forms and any additional hospital visit case report form that was completed by research staff. The primary economic outcome measure was the incremental cost per quality-adjusted life-year gained at 6 months from randomisation. We estimated costs from NHS resources and calculated quality-adjusted life-years from participant completion of the EuroQol-5 Dimensions, three-level version, at baseline, pre intervention, 1 week post intervention and 8 weeks and 6 months post randomisation.

RESULTS

In the shockwave lithotripsy arm, 67 out of 302 (22.2%) participants needed further treatment. In the ureteroscopic stone treatment arm, 31 out of 302 (10.3%) participants needed further treatment. The absolute risk difference was 11.4% (95% confidence interval 5.0% to 17.8%); the upper bound of the 95% confidence interval ruled out the prespecified margin of non-inferiority (which was 20%). The mean quality-adjusted life-year difference (shockwave lithotripsy vs. ureteroscopic stone treatment) was -0.021 (95% confidence interval 0.033 to -0.010) and the mean cost difference was -£809 (95% confidence interval -£1061 to -£551). The probability that shockwave lithotripsy is cost-effective is 79% at a threshold of society's willingness to pay for a quality-adjusted life-year of £30,000. The CEAC is derived from the joint distribution of incremental costs and incremental effects. Most of the results fall in the south-west quadrant of the cost effectiveness plane as SWL always costs less but is less effective.

LIMITATIONS

A limitation of the trial was low return and completion rates of patient questionnaires. The study was initially powered for 500 patients in each arm; however, the total number of patients recruited was only 307 and 306 patients in the ureteroscopic stone treatment and shockwave lithotripsy arms, respectively.

CONCLUSIONS

Patients receiving shockwave lithotripsy needed more further interventions than those receiving primary ureteroscopic retrieval, although the overall costs for those receiving the shockwave treatment were lower. The absolute risk difference between the two clinical pathways (11.4%) was lower than expected and at a level that is acceptable to clinicians and patients. The shockwave lithotripsy pathway is more cost-effective in an NHS setting, but results in lower quality of life.

FUTURE WORK

(1) The generic health-related quality-of-life tools used in this study do not fully capture the impact of the various treatment pathways on patients. A condition-specific health-related quality-of-life tool should be developed. (2) Reporting of ureteric stone trials would benefit from agreement on a core outcome set that would ensure that future trials are easier to compare.

TRIAL REGISTRATION

This trial is registered as ISRCTN92289221.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 19. See the NIHR Journals Library website for further project information.

Does quality of life in patients undergoing shock wave lithotripsy change with repeat procedures: a prospective pilot study from a teaching hospital

Introduction

Shock wave lithotripsy (SWL) is a well-established treatment for kidney stone disease (KSD) and despite its decreased popularity in the past, it has now gained renewed interest due to its minimally invasive nature and good outcomes, especially in the face of COVID-19 pandemic. The aim of our study was to perform a service evaluation to analyse and identify quality of life (QoL) changes [using Urinary Stones and Intervention Quality of Life (USIQoL) questionnaire] after repeat SWL treatments. This would enable a greater understanding of SWL treatment and reduce the current gap of knowledge regarding patient specific outcomes in the field.

Material and methods

Patients affected by urolithiasias underwent SWL treatment between September 2021 and February 2022 (6 months), were included in the study. A questionnaire was given to the patients in each SWL session and consisted of three main topic areas: a domain on Pain and Physical Health, on Psycho-social Health and on Work (see appendix below). Patients also completed a Visual Analogue Scale (VAS) in relation to the pain related to the treatment. Data from the questionnaires were collected and analysed.

Results

A total of 31 patients filled in two or more surveys, with a mean age of 55.8 years. On repeat treatments, pain and physical health domain was significantly better (p = 0.0046), psycho-social health domain was significantly better (p <0.001), work domain was significantly better (p = 0.009) and a correlation [on Visual Analog Scale (VAS)] was observed between pain decreasing in subsequent SWL procedures.

Conclusions

Our study found that the choice of SWL to treat KSD does improve a patient's QoL. This could be related to improvement of physical health, psychological and social wellbeing, and ability to work. Higher QoL and low pain scores are observed in relation to repeat SWL treatment and are not directly associated to stone-free status.

Decision-Making, Preference, and Treatment Choice for Asymptomatic Renal Stones-Balancing Benefit and Risk of Observation and Surgical Intervention: A Real-World Survey Using Social Media Platform

Introduction: The burden of kidney stone disease has risen, and several treatment options now exist. We wanted to evaluate the preference and treatment choices based on the information provided for management of hypothetical 8 and 15 mm renal stone, and factors that influenced their decision. Materials and Methods: An online questionnaire to investigate trends in decision-making for two hypothesized scenarios of asymptomatic kidney stones (8 and 15 mm) was formatted online in Microsoft Forms and posted on social media (Facebook) in Europe. The ethical approval was obtained from the University Ethics Committee, and data were collected from general public between September and November 2020. Results: A total of 476 participants of different age and background answered the survey with a male:female ratio of 1:2.7. The age groups were categorized as 18-25 years (n = 149), 26-49 years (n = 192), and 50+ years (n = 135). In the 8 mm scenario, 107 of the 476 participants (22.5%) chose observation, 249 (52.3%) chose extracorporeal shockwave lithotripsy (SWL) and 120 (25.2%) opted for ureteroscopy (URS). In the 15 mm scenario, 194 participants chose SWL treatment (40.8%), 216 (45.4%) URS, and 66 (13.9%) preferred percutaneous nephrolithotomy. The influencing factors were success rate, complication risk and invasiveness of the procedure. On comparison to 8 mm stone, while stent avoidance and activity limitation were considered less important with 15 mm stone (p < 0.001), complication rates were considered more important (p < 0.001). Conclusion: More than one treatment choice for kidney stones often exists and clinicians must take patient choice into account via an informed decision-making process. While some might accept a higher risk of invasiveness and complications for higher stone-free rate, others might have a more conservative approach to this. It is about time that urologists take patient priorities and concerns into account and perhaps use Patient Reported Outcome Measures in addition to clinical outcomes when comparing treatment success.

The development and application of a triage system for urolithiasis during COVID-19

Purpose

To balance epidemic prevention with the therapeutic needs of patients with urolithiasis during the COVID-19 pandemic, we developed a triage system to guide medical staff in making priority decisions.

Methods

The study began with a review of the literature to propose a theoretical framework. Then, focus groups were assembled to develop, supplement, refine and form a consensus on the indications of the triage system. Finally, the system was implemented in the clinic. The validity and reliability of the system were tested by a content validity index and the interrater reliability kappa coefficient. Changes in patient characteristics and waiting time before and after the epidemic were compared.

Results

The theoretical framework was based on disease pathophysiology, including obstruction, infection, kidney dysfunction, and other symptoms. With this guide, a 28-item triage system with categories of T1–5 (low priority to urgent) was developed. The content validity index and the interrater reliability coefficient were 0.833 and 0.812, respectively. During clinical application, although the total number of patients remained steady, the proportion of T1 decreased significantly; even though the overall waiting time of patients did not change significantly, it increased for T1 and decreased for T2–4 in 2020 compared with 2019 (P < 0.05).

Conclusion

This triage tool based on the dimensions of obstruction, infection, kidney dysfunction, and other symptoms has good psychometric properties and significant utility for prioritizing patients with urolithiasis during times of crisis. With this system, patients of moderate to high priority were treated promptly during the COVID-19 pandemic.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-021-03871-7.

Comparison of the Efficacy of Male Sexual Activity Versus Alpha-Blockers in the Expulsion of Distal Ureteric Stones: A Systematic Review and Meta-Analysis

Globally, the prevalence of urolithiasis is increasing, with limited effective treatment options. Though debate exists within the literature, the use of medical expulsive therapy (MET) for distal ureteric stones in the form of alpha-blockers is commonplace. Alpha-blockers work via the inhibition of norepinephrine, resulting in a small degree of distal ureteric relaxation. Nitric oxide (NO), the main neurotransmitter involved in penile erection, causes smooth muscle relaxation of the distal ureter. It is hypothesised that these alternative pathways may achieve the same desire clinical effect. To our knowledge, this is the first meta-analysis comparing the efficacy of male sexual activity, in the form of intercourse or masturbation, to alpha-blockers in the expulsion of ureteric stones. We conducted a comprehensive search of electronic databases (PubMed, MEDLINE, EMBASE, SCOPUS, CENTRAL and Google Scholar), identifying studies comparing male sexual activity versus alpha-blockers, in male patients with distal ureteric stones. The Cochrane risk-of-bias tool was used to assess the included studies. For data analysis, a random effects model was used in the event of significant heterogeneity (>75%), with fixed-effects modelling in the event of low-moderate heterogeneity. A search of electronic databases found three randomised control trials (RCTs), enrolling a total of 262 patients. There was no statistically significant difference observed when patients engaged in sexual activity rather than alpha-blocker, when looking at stone expulsion rate at two weeks (P=0.36), expulsion rate at four weeks (P=0.57), or the mean stone expulsion time (P=0.21). Furthermore, there was no significant difference observed when looking at analgesic requirements (P=0.43), or the requirement for additional procedures (P=0.57). Our meta-analysis demonstrated that male sexual activity as an alternative therapy for distal ureteric stones had comparable outcomes to the use of alpha-blocker, proving a viable alternative therapy in those patients wishing to avoid pharmacological management.

The Ascent of Artificial Intelligence in Endourology: a Systematic Review Over the Last 2 Decades

Purpose of Review

To highlight and review the application of artificial intelligence (AI) in kidney stone disease (KSD) for diagnostics, predicting procedural outcomes, stone passage, and recurrence rates. The systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist.

Recent Findings

This review discusses the newer advancements in AI-driven management strategies, which holds great promise to provide an essential step for personalized patient care and improved decision making. AI has been used in all areas of KSD including diagnosis, for predicting treatment suitability and success, basic science, quality of life (QOL), and recurrence of stone disease. However, it is still a research-based tool and is not used universally in clinical practice. This could be due to a lack of data infrastructure needed to train the algorithms, wider applicability in all groups of patients, complexity of its use and cost involved with it.

Summary

The constantly evolving literature and future research should focus more on QOL and the cost of KSD treatment and develop evidence-based AI algorithms that can be used universally, to guide urologists in the management of stone disease.

Gender Differences in Kidney Stone Disease (KSD): Findings from a Systematic Review

PURPOSE OF REVIEW

The prevalence of kidney stones is rising and historically carries a preponderance for males. However, recent evidence has questioned whether this gender gap is closing. The aim of this systematic review was to examine this further as well as evaluate possible underlying causes.

RECENT FINDINGS

Recent evidence confirms the disparity in kidney stone disease between genders is closing. In the modern era, the rise in prevalence among females has been greater, especially in adolescence. Quality of life is also more adversely affected by kidney stone events among females who are also more likely to develop sepsis after endourological surgery. Males, however, are more likely to present with stone events during periods of high ambient temperatures Recent literature demonstrates a temporal change in the disease burden of KSD among men and women. The latter, especially adolescent females, are more likely to develop KSD in their lifetime compared to previous eras. Determining causation is complex and continued research is warranted.

Variations of stress field and stone fracture produced at different lateral locations in a shockwave lithotripter field

During clinical procedures, the lithotripter shock wave (LSW) that is incident on the stone and resultant stress field is often asymmetric due to the respiratory motion of the patient. The variations of the LSW-stone interaction and associated fracture pattern were investigated by photoelastic imaging, phantom experiments, and three-dimensional fluid-solid interaction modeling at different lateral locations in a lithotripter field. In contrast to a T-shaped fracture pattern often observed in the posterior region of the disk-shaped stone under symmetric loading, the fracture pattern gradually transitioned to a tilted L-shape under asymmetric loading conditions. Moreover, the model simulations revealed the generation of surface acoustic waves (SAWs), i.e., a leaky Rayleigh wave on the anterior boundary and Scholte wave on the posterior boundary of the stone. The propagation of SAWs on the stone boundary is accompanied by a progressive transition of the LSW reflection pattern from regular to von Neumann and to weak von Neumann reflection near the glancing incidence and, concomitantly, the development and growth of a Mach stem, swirling around the stone boundary. The maximum tensile stress and stress integral were produced by SAWs on the stone boundary under asymmetric loading conditions, which drove the initiation and extension of surface cracks into the bulk of the stone that is confirmed by micro-computed tomography analysis.

A Systematic Review of Thulium Fiber Laser: Applications and Advantages of Laser Technology in the Field of Urology

Laser technology is widely used in urological surgery, from lithotripsy, prostate surgery to en-bloc resection of tumours. While Holmium:YAG has been widely employed over the last two decades, in recent years, there has been a surge of interest in Thulium Fiber Laser (TFL), which offers theoretical advantages of better water absorption and lower stone ablation thresholds. A systematic review was conducted to assess the evidence from clinical research on TFL's application for lithotripsy and prostate surgery. It identified 357 articles and 8 (1506 patients) were selected, of which 4 clinical studies each investigated TFL enucleation of prostate (ThuFLEP) and TFL lithotripsy. For flexible ureteroscopic lithotripsy (FURSL), stone ablation settings ranged from 0.1-4 J, and 7-300 Hz, mean operative time ranged from 23.4-39.8 minutes and lasing time ranged from 1.2-10 minutes. For stone dusting in percutaneous nephrolithotomy (PCNL), settings of 0.2 J and 125-200 Hz were found to be optimal. For ThuFLEP, all studies showed a significant improvement in IPSS (International Prostate Symptom Score), urinary flow rate (Qmax), quality of life measures, and post-void residual volume, with mean operative time ranging from 67-104.5 minutes. Our review shows that there is limited evidence on the use and clinical outcomes of TFL. ThuFLEP might suggest equivalence to the widely used HoLEP in the available evidence so far. TFL lithotripsy shows promising results but further prospective, randomized trials are required to properly assess its usability, clinical effectiveness and standardisation of the settings for successful adoption of the technology.

Validation of The Japanese Version of The Wisconsin Stone Quality of Life Questionnaire (WISQOL): Results from SMART Study Group

BACKGROUND

The Wisconsin Stone Quality of Life questionnaire (WISQOL) is a health-related quality of life measure designed for patients with urinary stones. It has been translated and used in several languages. This study aimed to validate the Japanese version of the WISQOL (J-WISQOL).

MATERIALS AND METHODS

The J-WISQOL was translated and validated using a multistep process proposed by the World Health Organization that involved forward translation, back-translation, and pilot testing with a group of patients. This study enrolled 150 patients with urinary stones who visited three academic hospitals for stone treatment. We assessed convergent validity of correlation patterns and internal consistency of the J-WISQOL and Short-Form 36-item survey version 2 (SF-36v2).

RESULTS

Overall, 150 patients were enrolled. The mean total score of the J-WISQOL was 108.18 ± 20.26 (raw score min-max, 28-140), suggesting that the onset and symptoms of urinary stones reduced the health-related quality of life in the patients. The J-WISQOL showed good internal consistency (Cronbach's α = 0.96) and inter-domain associations (Spearman's correlation coefficient r = 0.67-0.94). The J-WISQOL was correlated with the SF-36v2 in all domains: social, emotional, health, and vitality impact (r = 0.47-0.66).

CONCLUSION

The J-WISQOL is a reliable instrument for evaluating health-related quality of life measures in patients with urinary stones. It could be a useful quality of life questionnaire for urinary stones in Japan.

Outcomes of Ureteroscopy and Laser Stone Fragmentation (URSL) for Kidney Stone Disease (KSD): Comparative Cohort Study Using MOSES Technology 60 W Laser System versus Regular Holmium 20 W Laser

Background: For ureteroscopy and laser stone fragmentation (URSL), the use of laser technology has shifted from low power to higher power lasers and the addition of Moses technology, that allows for ‘fragmentation, dusting and pop-dusting’ of stones. We wanted to compare the outcomes of URSL for Moses technology 60 W laser system versus matched regular Holmium 20 W laser cases. Methods: Prospective data were collected for patients who underwent URSL using a Moses 60 W laser (Group A) and matched to historical control data using a regular Holmium 20 W laser (Group B), performed by a single surgeon. Data were collected for patient demographics, stone location, size, pre- and post-operative stent, operative time, length of stay, complications and stone free rate (SFR). Results: A total of 38 patients in each group underwent the URSL procedure. The stones were matched for their location (17 renal and 11 ureteric stones). The mean single and cumulative stone sizes (mm) were 10.9 ± 4.4 and 15.5 ± 9.9, and 11.8 ± 4.0 and 16.5 ± 11.3 for groups A and B, respectively. The mean operative time (min) was 51.6 ± 17.1 and 82.1 ± 27.0 (p ≤ 0.0001) for groups A and B. The initial SFR was 97.3% and 81.6% for groups A and B, respectively (p = 0.05), with 1 and 7 patients in each group needing a second procedure (p = 0.05), for a final SFR of 100% and 97.3%. While there were 2 and 5 Clavien I/II complications for groups A and B, none of the patients in group A had any infection related complication. Conclusions: Use of Moses technology with higher power was significantly faster for stone lithotripsy and reduced operative time and the number of patients who needed a second procedure to achieve a stone free status. It seems that the use of Moses technology with a mid-power laser is likely to set a new benchmark for treating complex stones, without the need for secondary procedures in most patients.

Outcomes and Cost Evaluation Related to a Single-Use, Disposable Ureteric Stent Removal System: a Systematic Review of the Literature

PURPOSE OF REVIEW

To present the latest evidence related to the outcomes and cost of single-use, disposable ureteric stent removal system (Isiris).

RECENT FINDINGS

Our review suggests that compared to a reusable flexible cystoscope (re-FC), a disposable flexible cystoscope (d-FC) with built-in grasper (Isiris) significantly reduced procedural time and provided a cost benefit when the latter was used in a ward or outpatient clinic-based setting. The use of d-FC also allowed endoscopy slots to be used for other urgent diagnostic procedures. Disposable FCs are effective and safe for ureteric stent removal. They offer greater flexibility and, in most cases, have been demonstrated to be cost-effective compared to re-FCs. They are at their most useful in remote, low-volume centres, in less well-developed countries and in centres where large demand is placed on endoscopy resources.

Deep learning model for automated kidney stone detection using coronal CT images

Kidney stones are a common complaint worldwide, causing many people to admit to emergency rooms with severe pain. Various imaging techniques are used for the diagnosis of kidney stone disease. Specialists are needed for the interpretation and full diagnosis of these images. Computer-aided diagnosis systems are the practical approaches that can be used as auxiliary tools to assist the clinicians in their diagnosis. In this study, an automated detection of kidney stone (having stone/not) using coronal computed tomography (CT) images is proposed with deep learning (DL) technique which has recently made significant progress in the field of artificial intelligence. A total of 1799 images were used by taking different cross-sectional CT images for each person. Our developed automated model showed an accuracy of 96.82% using CT images in detecting the kidney stones. We have observed that our model is able to detect accurately the kidney stones of even small size. Our developed DL model yielded superior results with a larger dataset of 433 subjects and is ready for clinical application. This study shows that recently popular DL methods can be employed to address other challenging problems in urology.

Association of Kidney Stone Disease (KSD) with Primary Gastrointestinal Surgery: a Systematic Review over Last 2 Decades

PURPOSE OF REVIEW

We aim to provide an up-to-date literature review to further characterise the association of kidney stone disease (KSD) with gastrointestinal (GI) surgery. As KSD is associated with significant morbidity, it is important to quantify and qualify this association to provide better care and management for the patient subgroup.

OBJECTIVE

To perform a systematic review of the existing literature to evaluate the association of KSD following GI surgery.

METHODS

A literature search was performed of the following databases: MEDLINE, EMBASE, Scopus, Google Scholar, Key Urology, Uptodate and Cochrane Trials from January 2000 to June 2020.

RECENT FINDINGS

A total of 106 articles were identified, and after screening for titles, abstracts and full articles, 12 full papers were included. This involved a total of 9299 patients who underwent primary GI surgery. Over a mean follow-up period of 5.4 years (range: 1-14.4 years), 819 (8.8%) developed KSD, varying from 1.2 to 83% across studies. The mean time to stone formation was approximately 3 years (range: 0.5-9 years). In the 4 studies that reported on the management of KSD (n = 427), 38.6% went on to have urological intervention. There is a high incidence of KSD following primary GI surgery, and after a mean follow-up of 3 years, around 9% of patients developed KSD. While the GI surgery was done for obesity, inflammatory bowel disease or cancer, the risk of KSD should be kept in mind during follow-up, and prompt urology involvement with metabolic assessment, medical and or surgical management offered as applicable.

Is flexible ureteroscopy and laser lithotripsy (FURSL) the new gold standard for paediatric lower pole stones: Outcomes from 2 large European tertiary paediatric endourology centres

INTRODUCTION

While paediatric ureteroscopy has been increasingly performed, the evidence for its use in paediatric lower pole stones (LPS) is sparce. In this study we look at the effectiveness and outcomes of flexible ureteroscopy and lasertripsy (FURSL) in the management of LPS for a paediatric population.

METHODS

Data were collected from two large European tertiary endourology centres which specialise in paediatric kidney stone management. The study was registered as an audit at the respective hospitals. All data were cross-checked and analysed using electronic operative notes, discharge records, laboratory systems and patient correspondence. The inclusion criteria were patients 16 years with lower pole stones having a FURSL procedure.

RESULTS

A total of 57 paediatric patients underwent FURSL for LPS. The mean age was 10.1 years + 4.7 (range: 1-16.9 years) with a male:female ratio of 2:3. The mean single stone size was 9.45+3.9 mm (range: 3-20 mm) and 31(54.4%) had multiple stones. A pre-operative stent was present in 18(31.6%) patients and a post-operative stent or ureteric catheter was left behind in 32(56.1%) patients. The initial and final SFR was 82.4% and 98.2% respectively with 1.19 procedures per patient performed to be stone free. While there were no intra-operative complications, there were only four(7%) minor complications (Clavien I) noted which were all simple urinary infections. No long-term complications were noted.

CONCLUSION

Flexible ureteroscopy and lasertripsy achieves excellent outcomes for treatment of paediatric LPS. While some patients might need a second procedure for complete stone clearance, FURSL may be considered as the first-line treatment of lower pole stones.

Urolithiasis prevalence in the Russian Federation: analysis of trends over a 15-year period

PURPOSE

To conduct a comparative analysis of the prevalence of urolithiasis in the Russian Federation.

METHODS

We analysed urolithiasis prevalence and incidence data from 2005 to 2019 (15 years) for the entire population of Russia. Data were provided by the 'Ministry of Health' of the Russian Federation. The prevalence and incidence of urolithiasis were collected and analysed for both adults and children for each region of the Russian Federation over this 15-year period. Statistical analysis was performed using the SPSS Statistics 21 software package (SPSS). Intergroup correlations and differences between samples in the studied parameters were considered significant at p < 0.05.

RESULTS

A total of 656,911 and 889,891 urolithiasis cases were observed in 2005 and 2019, respectively, an increase in urolithiasis prevalence of 35.4% for the study period, with the growth rate that was fairly uniform. The incidence of urolithiasis in the Russian Federation was 176,773 in 2005, while 205,414 new urolithiasis cases were recorded in 2019, with a clear tendency to a rising incidence of urolithiasis, an increase of 16.2% during the study period. The incidence per 100,000 in children remained stable during the entire period of analysis.

CONCLUSION

The incidence and prevalence of urolithiasis in the adult population steadily increased in all regions of the Russian Federation, while the incidence in children remained stable. The incidence of urolithiasis was associated with an increase in the incidence of diabetes mellitus, obesity and meat consumptions, highlighting the strong association of kidney stone disease with these risk factors.

Risk of Metabolic Syndrome in Kidney Stone Formers: A Comparative Cohort Study with a Median Follow-Up of 19 Years

Background: Kidney stone formers (SF) are more likely to develop diabetes mellitus (DM), but there is no study examining risk of metabolic syndrome (MetS) in this population. We aimed to describe the risk of MetS in SF compared to non-SF. Methods and Materials: SF referred to a tertiary referral metabolic centre in Southern England from 1990 to 2007, comparator patients were age, sex, and period (first stone) matched with 3:1 ratio from the same primary care database. SF with no documentation or previous MetS were excluded. Ethical approval was obtained and MetS was defined using the modified Association of American Clinical Endocrinologists (AACE) criteria. Analysis with cox proportional hazard regression. Results: In total, 828 SF were included after 1000 records were screened for inclusion, with 2484 age and sex matched non-SF comparators. Median follow-up was 19 years (interquartile range—IQR: 15–22) for both stone formers and stone-free comparators. SF were at significantly increased risk of developing MetS (hazard ratio—HR: 1.77; 95% confidence interval—CI: 1.55–2.03, p < 0.001). This effect was robust to adjustment for pre-existing components (HR: 1.91; 95% CI: 1.66–2.19, p < 0.001). Conclusions: Kidney stone formers are at increased risk of developing metabolic syndrome. Given the pathophysiological mechanism, the stone is likely a ‘symptom’ of an underlying metabolic abnormality, whether covert or overt. This has implications the risk of further stone events and cardiovascular disease.

Role of urinary biomarkers for diagnosis and prognosis of kidney stone disease

PURPOSE OF REVIEW

Urinary biomarkers such as neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1) and N-acetyl-B-D-glucosamindase (NAG) are recognised as being useful for the detection of kidney tubular damage but their role in the diagnosis and prognosis of kidney stone disease (KSD) is still unknown. To clarify this, we performed a systematic review of literature in accordance with Cochrane methodology from inception to September 2020.

RECENT FINDINGS

Twelve studies were included and a variety of urinary biomarkers (KIM-1, NGAL, NAG, proteins/peptides, cytokines, CA19-9) were measured in a total of 998 patients with KSD. Despite some contradicting studies, majority of the biomarkers studied showed a significant rise in patients with KSD compared to healthy controls, with levels decreasing after their surgical management, noticed as early as 4 h postprocedure. There was limited evidence of correlation with stone burden and elevated levels were also associated with hydronephrosis and superimposed infections.

SUMMARY

Urinary biomarkers could be used in the diagnosis, prognosis and stone-treatment response in patients with KSD. However, as novel indicators, they may not be reliable as the sole diagnostic or prognostic tool for KSD as they are readily confounded by other causes of kidney injury. Further studies are needed to determine their ability to separate KSD from other causes of obstructive uropathy and acute renal injury.

Quality of life of adult individuals with intestinal stomas in Uganda: a cross sectional study

Introduction

Intestinal stomas remain important life-saving surgical options in a wide range of gastrointestinal pathologies globally. Living with a stoma has potential to impair the patient's quality of life, often with associated negative psychological effects.

Objective

To evaluate the quality of life among intestinal stoma patients under Mulago National Referral Hospital (MNRH), with emphasis on psychological effects and effects on family-social interactions.

Methodology

A cross-sectional study carried out at surgical outpatient clinics of MNRH between January and June 2018. Data was collected using Stoma-QOL questionnaire, PHQ-9 and GAD-7 from 51 participants who had lived with intestinal stomas for at least a month.

Results

Of the 51 participants, male: female ratio was 4:1 and aged 18–84 years (mean age 44.04+18.47 years). 76.5% had colostomy; 23.5% had ileostomy. Majority (88.2%) had temporary stomas. The overall mean Stoma-QOL score was 55.12+ 17.04. Only about a quarter (24%) of participants had Stoma-QOL scores >70 (best). Most patients exhibited negative psychological effects (anxiety-100%, concerns about changed body image - 96.1% and depression - 88.4%).

Conclusion

Most participants had low levels of stoma-related quality of life, suffered negative psychological effects and exhibited limited social interactions. This calls for efforts to support Stoma patients adapt beter life.

Variations in the mineral content of bottled 'carbonated or sparkling' water across Europe: a comparison of 126 brands across 10 countries

Introduction

Kidney stone disease is a common disease with high recurrence rates. Sufficient intake of water is the cornerstone in primary prevention of stone disease. However, the mineral composition of water can affect urinary minerals and influence stone formation. The aim of this study is to assess the variation in the mineral composition of bottled sparkling or carbonated drinking water across Europe.

Material and methods

The two largest supermarket chains in each participating country were visited to obtain data on mineral composition regarding bicarbonate, calcium, magnesium, potassium, sodium and sulphates of sparkling or carbonated waters by reading the ingredient labels on the bottles supplied by the manufacturers. Alternatively, the web-shops of these supermarkets were consulted.

Results

In total, 126 sparkling water brands across ten European countries were analysed regarding mineral composition. The median concentrations per mineral varied greatly. The greatest variation in median mineral content was found for sodium and sulphates with levels ranging from 3.1 mg/l to 63.0 mg/l and 6.0 mg/l to 263.0 mg/l respectively. A wide distribution of calcium content was found in Switzerland, with calcium levels reaching up to 581.6 mg/l.

Conclusions

This study confirms that the mineral composition of sparkling or carbonated water varies greatly across Europe. Patients with kidney stone disease should be aware that the mineral content of water may influence stone formation and be mindful of the great variation that exists between different water brands. Mineral water can be a source of potential promotors or inhibitors of stone formation and patients and urologists need to be mindful of this.