Prevalence and trends of urolithiasis among adults

Potassium sodium hydrogen citrate intervention on gut microbiota and clinical features in uric acid stone patients

The high recurrence rate of renal uric acid stone (UAS) poses a significant challenge for urologists, and potassium sodium hydrogen citrate (PSHC) has been proven to be an effective oral dissolution drug. However, no studies have investigated the impact of PSHC on gut microbiota and its metabolites during stone dissolution therapy. We prospectively recruited 37 UAS patients and 40 healthy subjects, of which 12 patients completed a 3-month pharmacological intervention. Fasting vein blood was extracted and mid-stream urine was retained for biochemical testing. Fecal samples were collected for 16S ribosomal RNA (rRNA) gene sequencing and short chain fatty acids (SCFAs) content determination. UAS patients exhibited comorbidities such as obesity, hypertension, gout, and dyslipidemia. The richness and diversity of the gut microbiota were significantly decreased in UAS patients, Bacteroides and Fusobacterium were dominant genera while Subdoligranulum and Bifidobacterium were poorly enriched. After PSHC intervention, there was a significant reduction in stone size accompanied by decreased serum uric acid and increased urinary pH levels. The abundance of pathogenic bacterium Fusobacterium was significantly downregulated following the intervention, whereas there was an upregulation observed in SCFA-producing bacteria Lachnoclostridium and Parasutterella, leading to a significant elevation in butyric acid content. Functions related to fatty acid synthesis and amino acid metabolism within the microbiota showed upregulation following PSHC intervention. The correlation analysis revealed a positive association between stone pathogenic bacteria abundance and clinical factors for stone formation, while a negative correlation with SCFAs contents. Our preliminary study revealed that alterations in gut microbiota and metabolites were the crucial physiological adaptation to PSHC intervention. Targeted regulation of microbiota and SCFA holds promise for enhancing drug therapy efficacy and preventing stone recurrence. KEY POINTS: • Bacteroides and Fusobacterium were identified as dominant genera for UAS patients • After PSHC intervention, Fusobacterium decreased and butyric acid content increased • The microbiota increased capacity for fatty acid synthesis after PSHC intervention.

Evaluation of a urinary filtration device for kidney stone retrieval: Pi-Box®

INTRODUCTION

There is an unmet need to offer a proper urinary straining device for patients in whom spontaneous expulsion of stones is expected. The objective of this study was to assess the efficacity, duration and ease of use of a new filtration device: the Pi-Box®.

MATERIAL AND METHODS

This was a single-institution, non-randomized open-label study. Consecutive male patients with at least one stone that was susceptible of spontaneous passage, or after shockwave lithotripsy were included. The first 30 consecutive patients (Group 1) used the usual recommended techniques, and the 30 following consecutive patients (Group 2) were given the Pi-Box®. The patients completed a questionnaire when seen at 1-month follow-up.

RESULTS

Sixty men were included between January 2023 and May 2023. Thirteen (43%) patients retrieved a stone in each group (P=1). Filtration was performed for a median of 5 days in Group 1 and 10 days in Group 2 (P=0.03). Fourteen (46%) patients were satisfied or very satisfied with their filtration technique without the device versus 18 (60%) with the Pi-Box® (P=0.3). Eighteen (60%) and 21 patients (70%) would recommend their straining technique to a relative in groups 1 and 2, respectively (P=0.42).

CONCLUSIONS

The number of straining days was twice longer with the Pi-Box® device and is in favor of a better observance. The device did not increase the number of stones retrieved by urine filtration, which was high in this pilot study and may have been due to a participation bias.

LEVEL OF EVIDENCE

2B.

Prevalence and related factors of nephrolithiasis among medical staff in Qingdao, China: a retrospective cross-sectional study

BACKGROUND

Certain occupations may predispose individuals to urolithiasis, a multi-factorial disease. The study aimed to evaluate the prevalence and related factors of nephrolithiasis in medical staff in Qingdao, China.

METHODS

Physical examination results of 5115 in-service medical staff aged 22-60 years old were retrospectively analyzed. Multivariable logistic regression analysis and stratified analyses by age and gender were applied to explore the related factors of nephrolithiasis in these medical staff.

RESULTS

The overall nephrolithiasis prevalence in medical staff in Qingdao, China was 4.65%. Doctors were more prone to nephrolithiasis than nurses (5.63% vs. 3.96%, P = 0.013) and the peak prevalence (6.69%) was observed in medical staff working in the emergency department (ED). Male gender (OR = 1.615, 95% CI = 1.123-2.323, P = 0.010), overweight or obesity (OR = 1.674, 95% CI = 1.266-2.214, P < 0.001), work seniority ≥ 10 years (OR = 2.489, 95%CI = 1.675-3.699, P < 0.001) and working in the ED (OR = 1.815, 95% CI = 1.202-2.742, P = 0.005) were independent predictors for nephrolithiasis in medical staff based on the results of multivariate logistic regression analysis. The associations between overweight or obesity and nephrolithiasis risk as well as between work seniority ≥ 10 years and nephrolithiasis risk in medical staff were independent of age or gender in stratified analysis.

CONCLUSIONS

Nephrolithiasis prevalence in medical staff in Qingdao, China seemed not to be higher than that in the general population. Medical staff with work seniority ≥ 10 years and working in the ED should pay abundant attention to take measures to modify their nephrolithiasis risk.

The awareness of renal stones amongst Syrian refugees in northern Jordan

Kidney Stone Disease (KSD) is a globally prevalent condition that can be effectively addressed through proper education. This study investigated the awareness of kidney stones among refugees residing in northern Jordan. A questionnaire was administered to 487 refugees of diverse ages and socioeconomic backgrounds. Notably, 97.3% of the respondents had not attended university, and 30.8% held unskilled jobs. Upon familiarizing themselves with the signs and symptoms of kidney stones, 16.22% of men and 12.32% of women reported experiencing such symptoms. This revealed a significant association, suggesting that men might be more susceptible to developing kidney stones than women due to a lack of medical follow-up and examination for men in the camp. However, 38.77% of individuals were uncertain whether they had kidney stones. Furthermore, 38.96% of refugees were unsure about which healthcare professional to consult when experiencing kidney stone symptoms. This report highlights a serious issue with refugees' knowledge of the symptoms, causes, and treatments for kidney stones. The results indicate that Syrian refugees face challenges in acquiring adequate disease awareness, potentially related to issues of migration and war, including low levels of education, limited income, living in camps, and difficulties accessing treatments when needed. Implementing additional policies is necessary to address these challenges among Syrian refugees; however, further studies are needed to validate these findings.

The anti-urolithiasis activity and safety of strangury-relieving herbs: A comparative study based on fruit fly kidney stone model

ETHNOPHARMACOLOGICAL RELEVANCE

Urolithiasis is one of the oldest and most widespread urological diseases suffered globally. In the long history of Traditional Chinese Medicine, there're numerous herbs documented with strangury-relieving properties playing crucial roles in treating various urological disorders, including dysuria, hematuria, and renal colic, etc., which may be caused by urolithiasis. Exploring these herbs may reveal safer, more effective, and cost-efficient drugs and therapies for urolithiasis.

AIM OF THE STUDY

This study aims to assess the anti-urolithiasis efficacy and safety of 46 Chinese traditional and folk herbal drugs using the fruit fly (Drosophila melanogaster) kidney stone model, in order to identify the most valuable ethnomedicinal materials.

MATERIALS AND METHODS

Water extract and 50% ethanol extract of each herb were prepared respectively. 0.2% (w/w) sodium oxalate was chosen as appropriate lithogenic agent through fruit fly life span study. Male fruit-flies within three days of emergence were aged for an additional three days, then were randomly divided into experimental groups, model group and control groups (n = 20). The flies in blank control group, model group and positive control group were fed with standard food, standard food containing 0.2% sodium oxalate, standard food containing 0.2% sodium oxalate and 3% (w/w) Garcinia cambogia extract, respectively. Meanwhile, flies in the experimental groups were raised on standard food containing 0.2% sodium oxalate and 3% (w/w) herbal extract. The anti-urolithiasis capability of the extracts was evaluated using stone area ratio (the stone area divided by the area of the Malpighian tubule) and stone-clearing rate. Additionally, the 7-day mortality rate was employed as an indicator of safety.

RESULTS

Out of the 46 herbs, 24 exhibited significant anti-urolithiasis effects in their water extracts. Among them, Herba Nephrolepidis, Herba Humuli, Herba Desmodii Styracifolii, Cortex Plumeriae Rubrae, and Herba Mimosae Pudicae showed us a low 7-day mortality rate of fruit-flies as well. However, only a limited number of herbal extracts (8 out of 46) showed obvious anti-urolithiasis activity in their 50% ethanol extracts.

CONCLUSION

Highly potential anti-urolithiasis candidates were discovered from strangury-relieving herbs recorded in classical Traditional Chinese Medicine works, highlighting the significant value of traditional and folk ethnopharmacological knowledge.

A machine learning approach using stone volume to predict stone-free status at ureteroscopy

INTRODUCTION

To develop a predictive model incorporating stone volume along with other clinical and radiological factors to predict stone-free (SF) status at ureteroscopy (URS).

MATERIAL AND METHODS

Retrospective analysis of patients undergoing URS for kidney stone disease at our institution from 2012 to 2021. SF status was defined as stone fragments < 2 mm at the end of the procedure confirmed endoscopically and no evidence of stone fragments > 2 mm at XR KUB or US KUB at 3 months follow up. We specifically included all non-SF patients to optimise our algorithm for identifying instances with residual stone burden. SF patients were also randomly sampled over the same time period to ensure a more balanced dataset for ML prediction. Stone volumes were measured using preprocedural CT and combined with 19 other clinical and radiological factors. A bagged trees machine learning model with cross-validation was used for this analysis.

RESULTS

330 patients were included (SF: n = 276, not SF: n = 54, mean age 59.5 ± 16.1 years). A fivefold cross validated RUSboosted trees model has an accuracy of 74.5% and AUC of 0.82. The model sensitivity and specificity were 75% and 72.2% respectively. Variable importance analysis identified total stone volume (17.7% of total importance), operation time (14.3%), age (12.9%) and stone composition (10.9%) as important factors in predicting non-SF patients. Single and cumulative stone size which are commonly used in current practice to guide management, only represented 9.4% and 4.7% of total importance, respectively.

CONCLUSION

Machine learning can be used to predict patients that will be SF at the time of URS. Total stone volume appears to be more important than stone size in predicting SF status. Our findings could be used to optimise patient counselling and highlight an increasing role of stone volume to guide endourological practice and future guidelines.

Understanding formation processes of calcareous nephrolithiasis in renal interstitium and tubule lumen

Kidney stone, one of the oldest known diseases, has plagued humans for centuries, consistently imposing a heavy burden on patients and healthcare systems worldwide due to their high incidence and recurrence rates. Advancements in endoscopy, imaging, genetics, molecular biology and bioinformatics have led to a deeper and more comprehensive understanding of the mechanism behind nephrolithiasis. Kidney stone formation is a complex, multi-step and long-term process involving the transformation of stone-forming salts from free ions into asymptomatic or symptomatic stones influenced by physical, chemical and biological factors. Among the various types of kidney stones observed in clinical practice, calcareous nephrolithiasis is currently the most common and exhibits the most intricate formation mechanism. Extensive research suggests that calcareous nephrolithiasis primarily originates from interstitial subepithelial calcified plaques and/or calcified blockages in the openings of collecting ducts. These calcified plaques and blockages eventually come into contact with urine in the renal pelvis, serving as a nidus for crystal formation and subsequent stone growth. Both pathways of stone formation share similar mechanisms, such as the drive of abnormal urine composition, involvement of oxidative stress and inflammation, and an imbalance of stone inhibitors and promoters. However, they also possess unique characteristics. Hence, this review aims to provide detailed description and present recent discoveries regarding the formation processes of calcareous nephrolithiasis from two distinct birthplaces: renal interstitium and tubule lumen.

Desmodium styracifolium: Botanical and ethnopharmacological insights, phytochemical investigations, and prospects in pharmacology and pharmacotherapy

The purpose of this inquiry is to provide a conprehensive summary and analysis of the literature concerning the pharmacological properties of components that can be extracted from Desmodium styracifolium, a preparation in Chinese medicine. This study also aims to explore their potential application in elaborating medicinal products for the effective prevention and treatment of such conditions as urolithiasis, cholelithiasis, type 2 diabetes mellitus, metabolic syndrome, pro-oxidant and inflammatory processes, etc. Several experimental studies confirmed the potential of D. styracifolium to influence mineral metabolism, to decrease the concentration of constituents involved in the formation of urinary calculi, and to reduce mineral encrustation in the urinary tract, as well as to alleviate the damage caused by crystal structures. This beneficial impact is achieved through a combination of antioxidant and anti-inflammatory actions, along with urine alkalinization. The cholelitholytic, choleretic, and hepatoprotective effects of D. styracifolium plants have been confirmed, primarily ascribed to the activation of the hepatic Xα receptor and the bile acid receptor, farnesoid X receptor, by the flavonoid shaftoside. Special attention is focused on the potential therapeutic applications of flavonoids derived from D. styracifolium for diseases associated with the development of chronic inflammation and systemic response, emphasizing the ability of flavonoids to exert antioxidant and anti-inflammatory effects by acting directly and through the modulation of transcription factors. It is concluded that new strategies for the prevention and treatment of urolithiasis, cholelithiasis, type 2 diabetes mellitus, metabolic syndrome, acute and chronic inflammatory processes may rely on the promising development of dosage forms of D. styracifolium with their subsequent preclinical and clinical trials.

Longitudinal trend of urolithiasis incidence rates among world countries during past decades

INTRODUCTION

This study explores the trend of urolithiasis in various countries and categorizes the countries in terms of how their urolithiasis incidence rate has changed over time.

METHODS

The incidence rate of urolithiasis in 204 countries from 1990 to 2019, extracted from the Global Burden of Disease study, has been analyzed.

RESULTS

According to the results, all regions had experienced an increasing trend in urolithiasis rate, except for Eastern Europe, Central Europe, and Southeast Asia regions (decreasing rates of -71.4, -56.2, and -9.2 per 100000, respectively). Moreover, the Caribbean region had the highest increasing trend of urolithiasis rates, and Central Asia was in the next rank (increasing rate of 48.3 and 34.3 per 100,000, respectively, p-value < .05). Also, African regions revealed significant increasing trends over time (p-value < 0.05). The outstanding findings in cluster analysis showed that Afghanistan, Andorra, and Comoros had the most decreasing trend in urolithiasis rates over time (decreasing rate of -128.2 per 100000, p-value < .001). Cuba, Cyprus, Czechia, the Democratic People's Republic of Korea, Denmark, and Djibouti were in the next rank in terms of decreasing rate (decreasing rate of -92.3 per 100000, p-value < .001). In addition, urolithiasis rates in Congo, Eswatini, Gabon, and Grenada have the most increasing trend (increasing rate of 116.1 per 100000, p-value < .001).

CONCLUSION

The trend of urolithiasis rates was significantly increased in most countries, and Congo, Eswatini, Gabon, and Grenada had the highest trend among others. Also, Afghanistan, Andorra, and Comoros revealed the most decreasing rates, and the trend has dropped remarkably in several other countries.

A Prospective Study on the Impact of Clinical Factors and Adjusted Triple D System for Success Rate of ESWL

Objective: Our study aimed to evaluate the success rate of ESWL and identify relevant treatment-specific factors affecting treatment outcomes, as well as to assess the accuracy of the updated Triple D scoring system and compare it with older systems. Material and Methods: A prospective study of 71 patients who received ESWL treatment for renal stones that were 5-15 mm in size was completed. The patient having no residual stones or residual stones lesser than 4 mm after ESWL was identified as a treatment success. Univariate and multivariate logistic regression and ROC curves were used to identify important factors for treatment outcomes. Results: Successful treatment was achieved for 66.2% of patients. The stone volume (SV), mean stone density (MD), and delivered power to the stone volume unit ratio (SMLI/SV) were defined as the most critical factors influencing ESWL success. An updated Triple D score system with a, SMLI/SV ratio could be an alternative to older systems and reach an even higher accuracy. A limitation of this study is the limited sample size due to the COVID-19 pandemic. Conclusions: Our results show that the three factors that most influence the success of ESWL are the stone size, mean stone density, and SMLI/SV ratio. Based on this, we present a simple updated triple D score system to predict ESWL success, which could be implemented in future clinical practice.

Comprehensive prediction of urolithiasis based on clinical factors, blood chemistry and urinalysis: UROLITHIASIS score

Comprehensive prediction of urolithiasis using available factors obtained in the emergency department may aid in patient-centered diagnostic imaging decisions. This retrospective study analyzed the clinical factors, blood chemistry and urine parameters of patients who underwent nonenhanced urinary computed tomography for suspected urolithiasis. A scoring system was developed from a logistic regression model and was tested using the area under the curve (AUC). The prevalence of urolithiasis and important possible causes in the three risk subgroups were determined. Finally, the scoring model was validated. In the derivation cohort (n = 673), 566 patients were diagnosed with urolithiasis. Age > 35 years, history of urolithiasis, pain duration < 8 h, nausea/vomiting, costovertebral angle tenderness, serum creatinine ≥ 0.92 mg/dL, erythrocytes ≥ 10/high power field, no leukocytes ≤  + , and any crystalluria were retained in the final multivariable model and became part of the score. This scoring model demonstrated good discrimination (AUC 0.808 [95% CI, 0.776-0.837]). In the validation cohort (n = 336), the performance was similar (AUC 0.803 [95% CI, 0.756-0.844]), surpassing that of the STONE score (AUC 0.654 [95% CI, 0.601-0.705], P < 0.001). This scoring model successfully stratified patients according to the probability of urolithiasis. Further validation in various settings is needed.

The Degree of Hydronephrosis as an Indicator of the Necessity for Ureteric Dilatation during Ureteroscopic Lithotripsy

During rigid ureteroscopic lithotripsy, it is often encountered that the ureter is difficult to access. Attempts to advance the ureteroscope make the surgery more difficult. This study evaluated the preoperative predictive factors associated with difficult ureteral access (difficult ureter (DU)) during URS and assessed if clinical outcomes differed according to the degree of DU. This study identified 217 patients who underwent rigid ureteroscopic (URS) lithotripsy for the management of ureter stones between June 2017 and July 2021 in a tertiary hospital in Korea. In this group, preoperative factors were identified using univariate and multiple logistic regression analyses that could predict the degree of DU. Additionally, we also evaluated differences in treatment outcomes depending on the degree of DU. In 50 URS cases (22.0%), ureteral access using a ureteroscope was difficult. In the univariate and multivariate analyses, the degree of hydronephrosis was associated with the degree of DU. Treatment outcomes, extended operation times, low stone-free rate, postoperative pain, and secondary treatment were also significantly associated with the degree of DU. Clinicians can counsel patients with a lesser degree of hydronephrosis and approach their management accordingly.

Research progress on renal calculus associate with inborn error of metabolism

Renal calculus is a common disease with complex etiology and high recurrence rate. Recent studies have revealed that gene mutations may lead to metabolic defects which are associated with the formation of renal calculus, and single gene mutation is involved in relative high proportion of renal calculus. Gene mutations cause changes in enzyme function, metabolic pathway, ion transport, and receptor sensitivity, causing defects in oxalic acid metabolism, cystine metabolism, calcium ion metabolism, or purine metabolism, which may lead to the formation of renal calculus. The hereditary conditions associated with renal calculus include primary hyperoxaluria, cystinuria, Dent disease, familial hypomagnesemia with hypercalciuria and nephrocalcinosis, Bartter syndrome, primary distal renal tubular acidosis, infant hypercalcemia, hereditary hypophosphatemic rickets with hypercalciuria, adenine phosphoribosyltransferase deficiency, hypoxanthine-guanine phosphoribosyltransferase deficiency, and hereditary xanthinuria. This article reviews the research progress on renal calculus associated with inborn error of metabolism, to provide reference for early screening, diagnosis, treatment, prevention and recurrence of renal calculus.

GC-MS based metabolite profiling, antioxidant and antiurolithiatic properties of apple cider vinegar

Aim

To perform in vitro analysis of antioxidant and antiurolithiasis to carry out GC-MS-based metabolite profile.

Materials & methods

The effect of apple cider vinegar (ACV) in vitro, antioxidant and GC-MS analysis was evaluated. The antioxidant studies were performed. In vitro techniques included nucleation, aggregation and growth assay.

Results & conclusion

The presence of polyphenols, flavonoids, alkaloids and carbohydrates was shown. Concentrations from 5-30 μg/ml could dissolve calcium oxalate (p < 0.05) in vitro. The IC₅₀ value of ACV in DPPH was found to be around 7 μg/ml and the IC₅₀ value of the ACV in ABTS assay was around 9 μg/ml. Different phytocompounds were obtained from GC-MS analysis. ACV can be consumed to prevent kidney stones which seems helpful to the current therapy.

Cucumis callosus (Rottl.) Cogn. fruit extract ameliorates calcium oxalate urolithiasis in ethylene glycol induced hyperoxaluric Rat model

Cucumis callosus dry fruits are traditionally used as folk remedy to treat conditions like urethral irritations, urine stoppage or dribbling and other urinary ailments of man in north-west India. But no study is reported to validate this ethnic practice of using Cucumis fruit in urolithiasis. To evaluate anti-urolithiatic potential of Cucumis, hyperoxaluria was induced in rats by supplying 0.75% ethylene glycol (EG) + 1% ammonium chloride (AC) in drinking water for 14 days. Anti-urolithiatic activity of Cucumis callosus hydro-ethanolic extract (CCHEE) was assessed by measuring blood and urine biochemical parameters, oxidative stress indices, histopathology and osteopontin (OPN) expression. Administration of EG-AC to rats caused hyperoxaluria, crystalluria, azotaemia, oxidant/antioxidant imbalance (increase in lipid peroxidation (LPO), and decrease in glutathione (GSH) and catalase (CAT)), up-regulation of OPN and calcium oxalate (CaOx) crystal deposition in kidney. Treatment of afflicted rats with Cucumis fruits extract restored renal function to a great extent (CCHEE group), testified by improvement of stated parameters. Findings demonstrate curative efficacy of Cucumis fruit extract in EG induced urolithiasis of rats. The restoration of renal function was possibly by regulating renal stone formation via reducing urinary oxalate excretion, correcting oxidant/antioxidant imbalances, and reduced expression of OPN. Hence, results of this study validate the ethnic practice of using Cucumis fruit and conclude that fruit extracts have beneficial effects on CaOx urolithiasis and renal function.

Association between Urolithiasis and History Proton Pump Inhibitor Medication: A Nested Case-Control Study

A few retrospective studies have suggested the risk of urolithiasis associated with the use of proton pump inhibitors (PPIs). The current research intended to estimate the risk of urolithiasis according to previous PPI use. A nested case-control study was conducted using the National Health Insurance Service-National Health Screening Cohort in Korea. A total of 28,962 patients with urolithiasis and 115,848 control participants were selected. The previous prescription history of PPI with days of PPI prescription was collected. To calculate the odds ratios (OR) of past, current, and days of PPI use for urolithiasis, logistic regression models were used. Subgroup analyses were conducted. The urolithiasis group demonstrated a higher rate of current PPI users than the control group (60.9% vs. 43.7%). The current PPI users indicated 2.49 times higher odds for urolithiasis than no PPI users (95% confidence intervals [CI] = 2.33−2.66). A longer duration of PPI use was associated with greater odds for urolithiasis (adjusted OR = 1.65 (95% CI = 1.54−1.77) < 1.97 (95% CI = 1.84−2.11) < 2.32 (95% CI = 2.14−2.49) for 1−19 days, 30−364 days, and 365 or more days of PPI prescription). All subgroup analyses described a consistently positive association of previous PPI use with urolithiasis. Prior PPI use was related to a higher risk of urolithiasis. The relationship between previous PPI use and urolithiasis demonstrated a dose-response association.