Renal stone epidemiology in Rochester, Minnesota: an update

Association between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) and kidney stone: evidence from NHANES 2007-2018

BACKGROUND

As an innovative lipid parameter, NHHR (the ratio of non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol) can serve as a valuable tool for assessing cardiovascular disease risk. Nevertheless, the relationship between NHHR and the risk of kidney stones remains unexplored.

METHODS

A cross-sectional survey utilized data from the National Health and Population Survey (NHANES) database in the United States spanning from 2007 to 2018. Distinct statistical analyses were applied, including weighted logistic regression, stratified and interaction analysis and restricted cubic spline curve (RCS) models, to examine the correlation between NHHR and the incidence of kidney stones.

RESULTS

This analysis encompassed 24,664 participants, with 9.63% reporting incidents of kidney stones. Following multivariate logistic regression and comprehensive adjustments, participants in NHHR quartile 4 (OR 1.34; 95% CI 1.12, 1.60, P < 0.01) exhibited a significantly increased risk of kidney stones compared to those in NHHR quartile 1 (Q1). The RCS result further illustrated a non-linear correlation between NHHR and the incidence of kidney stones. The result of subgroup analysis manifested that participants without diabetes had a higher risk of kidney stones when measured high NHHR levels compared those with diabetes (p for interaction < 0.05).

CONCLUSION

Elevated NHHR levels were found to be associated with an increased risk of kidney stones. Based on these findings, NHHR appears to be a promising predictive indicator for the occurrence of kidney stones.

Substituted 4-methylcoumarin inhibitors of SLC26A3 (DRA) for treatment of constipation and hyperoxaluria

SLC26A3, also known as downregulated in adenoma (DRA), is an anion (Cl-, HCO3- and oxalate) exchanger in the luminal membrane of intestinal epithelial cells. Loss of DRA function in mice and humans causes congenital chloride-losing diarrhea and reduces urinary excretion of oxalate, a major constituent of kidney stones. Thus, inhibition of DRA is a potential treatment approach for constipation and calcium oxalate kidney stones. High-throughput screening previously identified 4,8-dimethylcoumarins (4a-4c) as DRA inhibitors, with lead candidate 4b having an IC50 of 40-50 nM for DRA inhibition. Here, we explored the effects of varying substituents at the 8-position, and replacing 8-methyl by 5-methyl (4e-4h). A focused library of 17 substituted compounds (4d-4t) was synthesized with good yield and purity. Compounds were tested for DRA inhibition potency using Fischer rat thyroid cells stably expressing DRA and a halide-sensitive YFP. Structure-activity analysis revealed that 8-bromo- (4m-4p) and 8-fluoro-coumarins (4q-4t) were slightly less potent than the corresponding 8-chloro analogs, demonstrating that the size of methyl or chloro substituents at the coumarin 8 position affects the potency. An analog containing 8-chlorocoumarin (4k) had ∼2-fold improved potency (IC50 25 nM) compared with the original lead candidate 4b. 5,8-Dimethylcoumarins were active against DRA, but with much lower potency than 4,8-disubstituted coumarins. In mice, orally administered 4k at 10 mg kg-1 reduced constipation and normalized stool water content in a loperamide-induced constipation model with comparable efficacy to 4b. Pharmacokinetic analysis of orally administered 4k at 10 mg kg-1 in mice indicated serum levels of >10 μM for at least six hours after single dose. This study expands SAR knowledge of 4,8-disubstituted coumarin inhibitors of DRA as novel drug candidates for constipation and kidney stones.

Naringen's Effects on Diuresis and Prevention of Urolithiasis in Hypertensive Rats

This research demonstrates the diuretic effect of naringenin, a flavanone aglycone found in citrus, on spontaneously hypertensive female and male rats (SHR). The data reinforces existing literature findings that male SHR exhibits higher systolic blood pressure than age-matched females. Urine volume assessed over 8 hours was lower when obtained from SHR males than females. When these animals were orally treated with different doses of naringenin (0.1-1 mg/kg), this increased urinary volume in both genders at the highest dose tested. In contrast, the lowest dose promoted a significant natriuretic effect. The other electrolytes analyzed in urine were not significantly altered, except potassium excretion, which was shown to be increased in the urine of SHR males. Furthermore, naringenin showed promise in reducing calcium oxalate (CaOx) crystal formation in an in vitro model, presenting potential advantages in lithiasis prevention.

Management of de novo nephrolithiasis after kidney transplantation: a comprehensive review from the European Renal Association CKD-MBD working group

The lifetime incidence of kidney stones is 6%-12% in the general population. Nephrolithiasis is a known cause of acute and chronic kidney injury, mediated via obstructive uropathy or crystal-induced nephropathy, and several modifiable and non-modifiable genetic and lifestyle causes have been described. Evidence for epidemiology and management of nephrolithiasis after kidney transplantation is limited by a low number of publications, small study sizes and short observational periods. Denervation of the kidney and ureter graft greatly reduces symptomatology of kidney stones in transplant recipients, which may contribute to a considerable underdiagnosis. Thus, reported prevalence rates of 1%-2% after kidney transplantation and the lack of adverse effects on allograft function and survival should be interpreted with caution. In this narrative review we summarize current state-of-the-art knowledge regarding epidemiology, clinical presentation, diagnosis, prevention and therapy of nephrolithiasis after kidney transplantation, including management of asymptomatic stone disease in kidney donors. Our aim is to strengthen clinical nephrologists who treat kidney transplant recipients in informed decision-making regarding management of kidney stones. Available evidence, supporting both surgical and medical treatment and prevention of kidney stones, is presented and critically discussed. The specific anatomy of the transplanted kidney and urinary tract requires deviation from established interventional approaches for nephrolithiasis in native kidneys. Also, pharmacological and lifestyle changes may need adaptation to the specific situation of kidney transplant recipients. Finally, we point out current knowledge gaps and the need for additional evidence from future studies.

Association between urinary lithiasis, other than struvite by crystallography and non-ureolytic bacteria

The relationship between urinary tract infection caused by urease-producing bacteria and lithiasis due to struvite stones is well established in the literature. However, there is limited knowledge on whether non-urease producing bacteria can also promote crystallization. In our study, we analyzed the association between urinary lithiasis, other than struvite by crystallography and non-ureolytic bacteria, in 153 patients who underwent surgery for urinary stone. The collected samples were sent for crystallographic analysis and culture. Additionally, preoperatory urine culture was collected for combined evaluation with the previous data. Percutaneous nephrolithotomy was the most commonly performed approach (45.8%). Struvite stones were more frequently identified in women (90.3%). Among stones with positive cultures, except struvite, 45.5% were composed of calcium oxalate monohydrate. The difference between urine culture and stone culture was different in 24.8% of the cases. Among stones with positive cultures that did not contain struvite, 86.4% showed non-urease bacteria in their cultures and 47.1% of struvite stones also did not have urease-producing bacteria in their cultures (p < 0.021). Our findings suggest that there is an association between non-ureolytic bacteria and stones that are not composed of struvite.

Effect of gender on presentation and outcome of renal colic

OBJECTIVES

To examine gender-related differences in the presentation, management, and outcomes of patients admitted to the emergency department ED with ureteral stones.

METHODS

Retrospective analysis of all patients admitted to the ED at our institution, found to have a ureteral stone on CT. Clinical, laboratory, imaging parameters, and outcomes were collected.

RESULTS

778 patients were admitted with ureteral stones between January 2018 and December 2020. 78% (n = 609) were males and 22% (n = 169) were females. The mean ages were 49.4 (SD 14.4) and 51.6 (SD 15.7) in males and females, respectively (p = 0.08). Female patients presented with a higher body temperature (p = 0.01), pulse rate (p < 0.0001), nausea and vomiting (p < 0.0001), elevated serum C-reactive protein (CRP) (p = 0.002) compared to males. The prevalence of elevated serum creatinine was higher in males (p < 0.0001). Alpha-blockers were recommended on discharge in 54.8% (334) of males, compared to only 29.6% (50) of females (p < 0.0001). Spontaneous stone expulsion was significantly higher in males compared to females (p = 0.01).

CONCLUSIONS

Our results demonstrate that gender does effect presentation and outcome of patients presenting with renal colic. Females were found to have elevated infectious parameters, more nausea and vomiting and a higher incidence of positive urine cultures. Males admitted to the ED were found to have significantly higher serum creatinine levels. Medical expulsive therapy (MET) with alpha-blockers was prescribed significantly less in female patients, which may have resulted in a lower spontaneous stone expulsion rate.

Polymorphic variations and mRNA expression of the genes encoding interleukins as well as enzymes of oxidative and nitrative stresses as a potential risk of nephrolithiasis development

Urolithiasis is one of the most common urological diseases worldwide with an unclear aetiology. However, a growing body of evidence suggests the potential role of molecular disturbances of the inflammation as well as oxidative and nitrative stresses, in the pathogenesis of urolithiasis. Therefore, we aimed to detect the potential association between six selected single-nucleotide polymorphisms (SNPs) and the development of nephrolithiasis. Moreover, we verified the association of urolithiasis development and mRNA expression of IL-6, IL-8, SOD2, and NOS2 in peripheral blood mononuclear cells (PBMCs). Total genomic DNA and mRNA were isolated from the peripheral blood of 112 patients with urolithiasis and 114 healthy subjects. Using Taq-Man® probes, we genotyped the following SNPs: rs1800797 and rs2069845 in IL-6, rs2227307 in IL-8, rs4880 in SOD2, rs2297518 and rs2779249 in NOS2. In turn, the evaluation of mRNA expression was performed using real-time PCR and 2-ΔCt methods. We found that the C/T genotype of the c.47 T>C-SOD2 SNP increased the frequency of urolithiasis occurrence whereas the T/T homozygote of the same polymorphism decreased the risk of urolithiasis development in the Polish population. Moreover, our study confirmed that patients with urolithiasis were characterised by decreased IL-6, IL-8, and SOD2 mRNA expression levels compared to the controls. In conclusion, our results suggest that polymorphic variants and changes in mRNA expression of IL-6, IL8, SOD2, and NOS2 may be involved in the pathophysiology of urolithiasis.

Totally tubeless, tubeless, and tubed percutaneous nephrolithotomy for treating kidney stones

BACKGROUND

Percutaneous nephrolithotomy (PNL) is the standard of care for removing large kidney stones (> 2 cm). Once the procedure is complete, different exiting strategies exist to manage the percutaneous tract opening, including placement of an external nephrostomy tube, placement of an internal ureteral stent, or no external or internal tube. The decision to place or not place a tube is handled differently among clinicians and may affect patient outcomes.

OBJECTIVES

To assess the effects of tubeless PNL (with ureteral stenting), totally tubeless PNL (without ureteral stenting or nephrostomy), and standard PNL (nephrostomy only) for the treatment of kidney stones in adults.

SEARCH METHODS

We performed a systematic literature search in multiple biomedical databases (CENTRAL, MEDLINE, Embase, Web of Science), as well as in two clinical trial registries. We also handsearched reference lists of relevant publications and conference proceedings. We applied no language restrictions. The latest search update was conducted in September 2022.

SELECTION CRITERIA

We included randomized controlled and quasi-randomized controlled trials of adult patients who received tubeless, totally tubeless, or standard PNL for treating kidney stones. We defined tubeless PNL as no nephrostomy tube, but ureteral stenting, while totally tubeless PNL meant no nephrostomy tube or ureteral stenting. Both interventions were compared to standard PNL with placement of a nephrostomy tube (only). We considered access tubes of any sizes. We only considered unilateral PNL with single-tract access. There were no exclusions on stone composition, size, or location.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the literature, extracted data, assessed risk of bias, and rated the certainty of evidence using GRADE. Primary outcomes were severe adverse events and postoperative pain, and secondary outcomes were operating time, length of hospital stay, and stone-free rate. We used the random-effects model for meta-analysis.

MAIN RESULTS

We included 10 studies in the review. Participant age varied among studies, ranging from 20 to 60 years. Detailed information on stone characteristics was rarely presented. Tubeless PNL versus standard PNL We are very uncertain whether there is a difference in severe adverse events (SAEs) between tubeless PNL and standard PNL (risk ratio (RR) 1.53, 95% confidence interval (CI) 0.14 to 16.46; I2 = 42%; 2 studies, 46 participants; very low-certainty evidence). Tubeless PNL may have little to no effect on pain on postoperative day one (mean difference (MD) 0.56 lower, 95% CI 1.34 lower to 0.21 higher; I2 = 84%; 4 studies, 186 participants; low-certainty evidence), and probably results in little to no difference in operating room time (MD 0.40 longer (in minutes), 95% CI 4.82 shorter to 5.62 longer; I2 = 0%; 3 studies, 81 participants; moderate-certainty evidence). Tubeless PNL may reduce length of hospital stay (MD 0.90 shorter, 95% CI 1.45 shorter to 0.35 shorter; I2 = 84%; 6 studies, 238 participants; low-certainty evidence). We are very uncertain of the effect of tubeless PNL on blood transfusions (RR 0.64, 95% CI 0.16 to 2.52; I2 = 0%; 4 studies, 161 participants; very low-certainty evidence), sepsis or fever (RR 0.50, 95% CI 0.05 to 4.75; I2 = not applicable; 2 studies, 82 participants; very low-certainty evidence), or readmissions (RR 1.00, 95% CI 0.07 to 14.21; I2 = not applicable, 1 study, 24 participants; very low-certainty evidence). Totally tubeless versus standard PNL Totally tubeless PNL may result in lower SAE rates (RR 0.49, 95% CI 0.19 to 1.25; I2 = 0%; 2 studies, 174 participants; low-certainty evidence) and pain on postoperative day one (MD 3.60 lower, 95% CI 4.24 lower to 2.96 lower; I2 = Not applicable; 1 study, 50 participants; low-certainty evidence). Totally tubeless PNL may result in little to no difference in operating room time (MD 6.23 shorter (in minutes), 95% CI 14.29 shorter to 1.84 longer; I2 = 72%; 2 studies, 174 participants; moderate-certainty evidence) and sepsis or fever (RR 0.33, 95% CI 0.01 to 7.97; I2 = not applicable; 1 study, 90 participants; low-certainty evidence). Totally tubeless PNL likely shortens the length of hospital stay (MD 1.55 shorter, 95% CI 1.82 shorter to 1.29 shorter; I2 = 0%; 4 studies, 274 participants; moderate-certainty evidence). We are very uncertain of the effect of totally tubeless PNL on blood transfusions (RR 0.62, 95% CI 0.26 to 1.48; I2 = 0%; 4 studies, 274 participants; very low-certainty evidence) or readmissions (RR not estimable, 95% CI not estimable; I2 = not applicable; 1 study, 50 participants; very low-certainty evidence). We found no studies comparing tubeless mini versus standard mini-PNL or totally tubeless mini versus standard mini-PNL.

AUTHORS' CONCLUSIONS

When comparing tubeless to standard PNL with regard to the predefined primary outcomes of this review, there may be little difference in early postoperative pain, while we are very uncertain of the effect on SAEs. People treated with tubeless PNL may benefit from a reduced length of stay compared to standard PNL. When comparing totally tubeless to standard PNL, early postoperative pain and severe adverse events may be reduced with totally tubeless PNL. The certainty of evidence by outcome was mostly very low (range: moderate to very low) for the comparison of tubeless to standard PNL and low (range: moderate to very low) for the comparison of totally tubeless to standard PNL. The most common reasons for downgrading the certainty of the evidence were study limitations, inconsistency, and imprecision. We did not find randomized trial evidence for other comparisons. Overall, further and higher-quality studies are needed to inform clinical practice.

Pattern of Surgical Diseases Affecting Females in a Teaching Hospital in Central India: A Demographic Study

Introduction  Despite progress in eliminating the social and health disparity between men and women during the last century, gender equality remains an elusive goal, particularly in the developing world. This gender-based bias has been found to directly result into poor health outcome in females. Hence, it is vital to know the number and pattern of surgical diseases affecting females in any setup, so as to improve their admission rates and reach out to this neglected half of population. Materials and Methods  This was a demographic study done at a teaching hospital in Central India from January to June 2020. Data of patients discharged from female surgery ward were collected from medical record department. Age, diagnosis, urban-rural distribution, and length of hospital stay of patients were noted, and data were analyzed statistically. Results  A total of 187 patient records were studied, which revealed that the mean age of the patients was 40.35 years; maximum patients were of gastrointestinal surgery (53.42%) in which the most common diagnosis was cholelithiasis (25.13%). Urological diseases (15.50%), breast diseases (12.83%), perianal disease (9.09%), and thyroid diseases (5.34%) were found in decreasing order of frequency. Overall hospital stays of patients ranged from 1 to 14 days with average stay of 6.35 days. Conclusion  In our study, cholelithiasis was found to be the most common surgically treated disease followed by urological diseases. Breast symptoms, although commonly affecting females, did not turn into admissions as there remains a social taboo attached to it. Breast cancer still presents late, despite being the most common cancer in females in India. Approximately 65% patients were discharged within first 5 days of their admission, which indicates good hospital care and improves patient satisfaction levels. Still there is greater need for public health efforts to improve the monitoring, safety, and availability of surgical services to female patients.

Prevalence of Stone Disease and Procedure Trends in the United States

OBJECTIVE

To evaluate the prevalence of stone disease and procedure trends among US commercial and Medicare populations.

METHODS

Retrospective analyses for a US commercial population and Medicare population were conducted using the Merative MarketScan Commercial Database and Medicare Standard Analytic File (5% sample), respectively. Patients aged 18+ were included if they had an encounter in any setting with a primary stone diagnosis or stone procedure (ureteroscopy [URS], percutaneous nephrolithotomy (PCNL), or shockwave lithotripsy [SWL]) between 2011 and 2019. Analyses were conducted at the patient level.

RESULTS

Over the study time horizon, the prevalence of stone disease showed a small yet statistically significant decrease in the commercial population (1.04%-1.01%; P.ß<.ß0.0001) and a statistically significant increase in the Medicare population (1.84%-2.34%; P.ß<.ß0.0001). URS.ßprocedure volumes increased by 22.6% (P.ß<.ß0.0001) in the commercial population and by 56.6% (P.ß<.ß0.0001) in the Medicare population over the study period. Similarly, PCNL.ßprocedure volumes increased by 17.4% (P.ß<.ß0.0001) in the commercial population and 27.5% (P.ß<.ß0.0001) in the Medicare population. Procedure volumes for SWL decreased by 26.9% in the commercial population (P.ß<.ß0.0001) and by 3.8% in the Medicare population although the results were not statistically significant.

CONCLUSION

The prevalence of stone disease showed a small decrease in the US commercial population and an increase in the Medicare population over the study time horizon. In both populations, increasing procedure volumes were observed for URS and PCNL while decreasing volumes were observed for SWL.

Hormonal and molecular characterization of calcium oxalate stone formers predicting occurrence and recurrence

The purpose of the study is to investigate the role of sex hormones, androgen receptors (ARs) and miRNA/CSF-1 in occurrence and recurrence of calcium oxalate (CaOx) renal urolithiasis. In this prospective study, 74 patients with CaOx stones; stone formers group (SFG) and 40 healthy subjects; control group were compared. SFG includes both de novo and recurrent cases. Steroid sex hormone plasma assay including testosterone, free testosterone, dihydrotestosterone, estradiol, and sex hormone binding globulin was analyzed. ARs, miRNA-185-5p and CSF-1 expression were compared between the groups. SFG showed significant higher ARs and miRNA-185-5p expression (3.7 ± 1.3, 1.8 ± 0.4, respectively) than control group (1 ± 0.08 and 1 ± 0.07, respectively) (p < 0.05). However, CSF-1 expression was significantly lower in stone formers than control group (0.4 ± 0.19 vs 1 ± 0.1, respectively) (p < 0.05). No differences were detected between de novo and recurrent SFG regarding sex hormones, AR, miRNA or CSF-1 expression. Our data suggest the important role of AR, miRNA and CSF-1 signaling in human nephrolithiasis pathogenesis.

The association between menopause, postmenopausal hormone therapy, and kidney stone disease in Taiwanese women

PURPOSE

The association between menopause, postmenopausal hormone therapy, and kidney stone disease has long been a topic of discussion and is still unclear. Moreover, most previous research has focused on Caucasians. Therefore, we aimed to explore this issue in an Asian population.

METHODS

In this cross-sectional study, we enrolled female participants aged between 30 and 70 years from the Taiwan Biobank. The presence of kidney stone disease (KSD) was defined through a self-reported questionnaire. The participants were divided into two groups according to the presence of menopause; premenopausal and postmenopausal groups. The associations among menopause, postmenopausal hormone therapy, and KSD were examined using binary logistic regression models.

RESULTS

A total of 17,460 women with available information were recruited, including 5976 in the premenopausal group and 11,484 in the postmenopausal group. Compared to the premenopausal group, the postmenopausal group had a significantly higher prevalence of KSD (3% vs. 6%). The odds ratio for KSD was higher in the postmenopausal group than in the premenopausal group (odds ratio = 1.50; 95% confidence interval = 1.17-1.92) after adjusting for confounders. We also examined associations between the type of menopause (natural and surgical) and KSD, and found that both types of menopause were associated with KSD in age-adjusted and multivariable models. Compared with those who had never received postmenopausal hormone therapy, those who had received postmenopausal hormone therapy were not associated with a higher risk of KSD.

CONCLUSIONS

Our study suggests that natural and surgical menopause were associated with KSD. However, we found no association between the postmenopausal hormone therapy and KSD in the postmenopausal women.

Safety and efficacy of ureteroscopy for urolithiasis in octogenarians

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Global, Regional, and National Incidence and Disability-Adjusted Life-Years for Urolithiasis in 195 Countries and Territories, 1990-2019: Results from the Global Burden of Disease Study 2019

Purpose: Urolithiasis is highly prevalent worldwide. The aim of this study was to report the results of the Global Burden of Disease 2019 study on urolithiasis burden estimates grouped by gender, regions, countries or territories, and sociodemographic index (SDI) from 1990 to 2019 globally. Methods: We reported detailed estimates and temporal trends of the burden estimates of urolithiasis from 1990 to 2019 in 195 countries and territories and further evaluated the relationship between these estimates and SDI, a composite indicator of income per person, years of education, and fertility as a measurement of country/region socio-economic level. Urolithiasis incidence and disability-adjusted life years by gender, regions, countries or territories, and SDI were reported. The percentage change and estimated annual percentage change of these burden estimates were calculated to quantify temporal trends. Results: From 1990 to 2019, the age-standardized incidence rate (ASIR) and disability-adjusted life years (DALYs) of urolithiasis decreased globally by 0.459% and 1.898% per year, respectively. Such a trend of ASIR was prominently due to the decline in the middle, high-middle, and high SDI countries, including Eastern Asia, high-income Eastern Europe, and high-income North America. During this period, these estimates increased in low and low-middle SDI countries, particularly in South Asia, Andean Latin America, and Western Europe. A decline in DALYs was observed in all SDI countries. An approximate positive linear association existed between the burden estimate's decreased APC and SDI level, except at the high SDI level. Both males and females showed the same trend. Conclusions: This study provides comprehensive knowledge of the burden estimate of urolithiasis. Although the burden estimates of urolithiasis showed a global decrease during the past 29 years, this progress has yet to be universal; the increasing trends were observed in countries with low and low-middle SDI countries. Research in these countries is needed and helps with the appropriate allocation of health resources for prevention, screening, and treatment strategies.

Construction of a ternary component chip with enhanced desorption efficiency for laser desorption/ionization mass spectrometry based metabolic fingerprinting

Introduction: In vitro metabolic fingerprinting encodes diverse diseases for clinical practice, while tedious sample pretreatment in bio-samples has largely hindered its universal application. Designed materials are highly demanded to construct diagnostic tools for high-throughput metabolic information extraction. Results: Herein, a ternary component chip composed of mesoporous silica substrate, plasmonic matrix, and perfluoroalkyl initiator is constructed for direct metabolic fingerprinting of biofluids by laser desorption/ionization mass spectrometry. Method: The performance of the designed chip is optimized in terms of silica pore size, gold sputtering time, and initiator loading parameter. The optimized chip can be coupled with microarrays to realize fast, high-throughput (∼second/sample), and microscaled (∼1 μL) sample analysis in human urine without any enrichment or purification. On-chip urine fingerprints further allow for differentiation between kidney stone patients and healthy controls. Discussion: Given the fast, high throughput, and easy operation, our approach brings a new dimension to designing nano-material-based chips for high-performance metabolic analysis and large-scale diagnostic use.

Association between the systemic immune-inflammation index and kidney stone: A cross-sectional study of NHANES 2007-2018

Background

The incidence rate of kidney stones increased over the past decades globally, which brought medical expenditure and social burden. The systemic immune-inflammatory index (SII) was initially identified as a prognosis of multiple diseases. We performed an updated analysis on the impact of SII on kidney stones.

Methods

This compensatory cross-sectional study enrolled participants from the National Health and Nutrition Examination Survey 2007-2018. Univariate and multivariate logistic regression analyses were performed to investigate the association between SII and kidney stones.

Results

Of the 22220 participants, the mean (SD) age was 49.45 ± 17.36 years old, with a 9.87% incidence rate of kidney stones. A fully adjusted model showed that SII higher than 330 x 10⁹/L was parallel associated with kidney stones (Odds ratio [OR] = 1.282, 95% Confidence interval [CI] = 1.023 to 1.608, P = 0.034) in adults aged 20-50. However, no difference was found in the elderly subgroup. Multiple imputation analyses confirmed the robustness of our results.

Conclusions

Our findings suggested SII was positively associated with a high risk of kidney stones in US adults aged less than 50. The outcome compensated for previous studies that still needed more large-scale prospective cohorts for validation.

Shockwaves and the Rolling Stones: An Overview of Pediatric Stone Disease

Urinary stone disease is a common problem in adults, with an estimated 10% to 20% lifetime risk of developing a stone and an annual incidence of almost 1%. In contrast, in children, even though the incidence appears to be increasing, urinary tract stones are a rare problem, with an estimated incidence of approximately 5 to 36 per 100,000 children. Consequently, typical complications of rare diseases, such as delayed diagnosis, lack of awareness, and specialist knowledge, as well as difficulties accessing specific treatments also affect children with stone disease. Indeed, because stone disease is such a common problem in adults, frequently, it is adult practitioners who will first be asked to manage affected children. Yet, there are unique aspects to pediatric urolithiasis such that treatment practices common in adults cannot necessarily be transferred to children. Here, we review the epidemiology, etiology, presentation, investigation, and management of pediatric stone disease; we highlight those aspects that separate its management from that in adults and make a case for a specialized, multidisciplinary approach to pediatric stone disease.

Association between sleep quality and urolithiasis among general population in Western China: a cross-sectional study

Background

Growing number of studies have evidently shown that sleep disorders are associated with the recently increased risk of various diseases in general human population. However, the relationship between sleep quality and urolithiasis condition in humans is still unclear. The present study explored the relationship between quality of sleep and urolithiasis in Chinese population of population, western China and hence investigated the effects of sleep quality on urolithiasis disease.

Methods

A cross-sectional analysis was performed using data from the West China Natural Population Cohort Study (WCNPCS). The data was collected between May 2019 and June 2021. This study evaluated the association between the sleep quality and urolithiasis. The sleep quality was assessed using the Chinese version of the Pittsburgh Sleep Quality Index (PSQI) whereas urolithiasis, as the outcome was a binary variable. Multivariable logistic regression models that adjust the sociodemographic characteristics and health-related factors were used to assess the association between sleep quality and urolithiasis. Interaction was tested in prespecified subgroup of interest.

Results

After adjusting a series of confounding variables, the Pittsburgh Sleep Quality Index scores were found to have a significant positive correlation with the prevalence of urolithiasis (OR: 1.178; 95% CI = 1.083–1.282; p < 0.001). The risk of urolithiasis was significantly increased with an elevation of the component Pittsburgh Sleep Quality Index score in sleep latency, sleep duration, habitual sleep efficiency, and daytime dysfunction.

Conclusions

It was evident that there is an association between sleep quality and prevalence of renal stones in natural population in western China regions. Poor sleep quality is related to urolithiasis. The findings of the current study hence highlighted the need for future public health guidelines to develop detailed strategies for improving sleep quality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14187-5.

Effect of age on presentation and outcome in renal colic

Objectives:

To examine the age-related differences in the presentation, management, and outcomes of patients admitted to the emergency department (ED) with ureteral stones.

Patients and methods:

A retrospective analysis of all patients who visited the ED at a single institution that were found to have a ureteral stone on CT. Clinical, laboratory, and imaging parameters were collected, including outcomes. Patients were subdivided into age groups: 18–30, 31–50, 51–70, and >70 years.

Results:

Between January 2018 and December 2020, 778 patients were admitted to the ED with a ureteral stone. About 78% (609) were males and 22% (169) were females. The mean ages were 49.4 (SD 14.4) and 51.6 (SD 15.7) in males and females, respectively ( p = 0.08). Patients in the 36–50 age group, had significantly higher visual analogue scale (VAS) scores ( p < 0.0001). Patients older than 70 years old presented with significantly higher serum creatinine levels ( p < 0.0001), C-reactive protein (CRP) ( p < 0.001) and leukocyte levels ( p = 0.002). These patients were also found to have significantly larger stones (mean size of 6.2 mm (SD 4.8) ( p < 0.0001)) and underwent percutaneous nephrolithotripsy (PCNL) in significantly higher numbers (56.3% vs 43.8%, ( p < 0.0001)). Less than half of the patients older than 50 years were given medical expulsive therapy (MET) with alpha-blockers, compared to more than 50% in the other age groups ( p = 0.002). Spontaneous stone expulsion was noted in 70.2% of the 18–35-year group, 62.4% of the 36–50-year-old group, 51.8% of the 51–70-year-old group, and 37% of the >70-year-old group ( p < 0.0001). The ED re-admission rates at 7 and 30 days were not significantly different among all age groups.

Conclusions:

Our data suggests that older patients presented with larger stones, elevated inflammatory markers and creatinine and were more likely to require surgical intervention. The spontaneous stone expulsion rate was inversely associated with age.

Skeletal and extraskeletal disorders of biomineralization

The physiological process of biomineralization is complex and deviation from it leads to a variety of diseases. Progress in the past 10 years has enhanced understanding of the genetic, molecular and cellular pathophysiology underlying these disorders; sometimes, this knowledge has both facilitated restoration of health and clarified the very nature of biomineralization as it occurs in humans. In this Review, we consider the principal regulators of mineralization and crystallization, and how dysregulation of these processes can lead to human disease. The knowledge acquired to date and gaps still to be filled are highlighted. The disorders of mineralization discussed comprise a broad spectrum of conditions that encompass bone disorders associated with alterations of mineral quantity and quality, as well as disorders of extraskeletal mineralization (hyperphosphataemic familial tumoural calcinosis). Included are disorders of alkaline phosphatase (hypophosphatasia) and phosphate homeostasis (X-linked hypophosphataemic rickets, fluorosis, rickets and osteomalacia). Furthermore, crystallopathies are covered as well as arterial and renal calcification. This Review discusses the current knowledge of biomineralization derived from basic and clinical research and points to future studies that will lead to new therapeutic approaches for biomineralization disorders.

Small molecule inhibitor of intestinal anion exchanger SLC26A3 for therapy of hyperoxaluria and nephrolithiasis

Nephrolithiasis is a common and recurrent disease affecting 9% of the US population. Hyperoxaluria is major risk factor for calcium oxalate kidney stones, which constitute two-thirds of all kidney stones. SLC26A3 (DRA, downregulated in adenoma) is an anion exchanger of chloride, bicarbonate, and oxalate thought to facilitate intestinal oxalate absorption, as evidenced by approximately 70% reduced urine oxalate excretion in knockout mice. We previously identified a small-molecule SLC26A3 inhibitor (DRA_inh-A270) that selectively inhibited SLC26A3-mediated chloride/bicarbonate exchange (IC₅₀ ~ 35 nM) and, as found here, oxalate/chloride exchange (IC₅₀ ~ 60 nM). In colonic closed loops in mice, luminal DRA_inh-A270 inhibited oxalate absorption by 70%. Following oral sodium oxalate loading in mice, DRA_inh-A270 largely prevented the 2.5-fold increase in urine oxalate/creatinine ratio. In a mouse model of oxalate nephropathy produced by a high-oxalate low-calcium diet, vehicle-treated mice developed marked hyperoxaluria with elevated serum creatinine, renal calcium oxalate crystal deposition, and renal injury, which were largely prevented by DRA_inh-A270 (10 mg/kg twice daily). DRA_inh-A270 administered over 7 days to healthy mice did not show significant toxicity. Our findings support a major role of SLC26A3 in intestinal oxalate absorption and suggest the therapeutic utility of SLC26A3 inhibition for treatment of hyperoxaluria and prevention of calcium oxalate nephrolithiasis.

Association between Temperature and Inpatient Stone Admission in a Pediatric Population

BACKGROUND

Higher temperatures have been associated with increased stone formation and subsequent utilization of hospital resources, including inpatient admission. However, these observations have been derived from the adult population. We sought to examine if this purported association extends to the pediatric population.

METHODS

We used the 2016 Kids' Inpatient Database to identify nationwide pediatric inpatient admissions related to nephrolithiasis. Temperature data from the National Oceanic and Atmospheric Administration was linked to each admission. Comparative statistics analyzed patient and admission characteristics. Multivariable logistic regression analyzed associations between stone-related admissions and temperature. As a frame of reference, this analysis was replicated using the National Inpatient Sample from 2016 to evaluate associations in the adult population.

RESULTS

Of the 2,496,257 pediatric admissions, 8,453 (0.33%) were related to nephrolithiasis. Temperatures at the time of stone admission were higher than those during non-stone admission (55.9°F vs. 54.8°F, P<0.001). The stone admission group had a higher proportion of females than the non-stone admission group (64.8% vs. 55.4%, P<0.001). Stone admission was significantly associated with temperature (OR 1.025 per 10°F, 95% CI 1.003-1.049, P=0.03) and female sex (OR 1.097, 95% CI 1.027-1.171, P=0.006). In the adult population, 380,520 out of 30,000,941 patients (1.3%) were admitted with a stone. The effect of temperature on stone admissions was similar to that in the pediatric population (OR 1.020, 95% CI 1.014-1.026, P<0.001), but women were over 20% less likely to be admitted for stones than men (OR 0.770, 95% CI 0.757-0.784, P<0.001).

CONCLUSIONS

Increased temperatures were associated with an increased risk of stone-related admission in both the pediatric and adult populations. Females were at increased risk for stone-related admissions during childhood, but this trend reverses in adulthood.

The genetics of kidney stone disease and nephrocalcinosis

Kidney stones (also known as urinary stones or nephrolithiasis) are highly prevalent, affecting approximately 10% of adults worldwide, and the incidence of stone disease is increasing. Kidney stone formation results from an imbalance of inhibitors and promoters of crystallization, and calcium-containing calculi account for over 80% of stones. In most patients, the underlying aetiology is thought to be multifactorial, with environmental, dietary, hormonal and genetic components. The advent of high-throughput sequencing techniques has enabled a monogenic cause of kidney stones to be identified in up to 30% of children and 10% of adults who form stones, with ~35 different genes implicated. In addition, genome-wide association studies have implicated a series of genes involved in renal tubular handling of lithogenic substrates and of inhibitors of crystallization in stone disease in the general population. Such findings will likely lead to the identification of additional treatment targets involving underlying enzymatic or protein defects, including but not limited to those that alter urinary biochemistry.

Characteristics and Types of Urolithiasis in the Eastern Region of Saudi Arabia: A Single-Center Retrospective Study

Introduction

Urolithiasis is one of the most common conditions encountered in clinical practice with the prevalence increasing globally in the last few decades. Urolithiasis has been found to be more common in areas with a hot climate, such as Saudi Arabia. The aim of this study was to determine the characteristics and the types of urolithiasis most frequently found in the Eastern Region of Saudi Arabia.

Methods

This was a single-center retrospective cohort study based on data extracted from an electronic hospital information system (BESTCare) of all patients diagnosed with urolithiasis at King Abdulaziz Hospital, a tertiary care center in Saudi Arabia's Eastern Region. From January 2013 to December 2016, all adult patients aged 18 and up who presented with urinary calculi (renal and ureter) were included in the study.

Results

A total of 235 patients were reviewed, with a mean age of 48.52 years. Renal calculi were more prevalent in males (74.5%). Calcium oxalate was the predominant type (76%), followed by uric acid calculi (18%) and cystine calculi (4.8%). A small proportion (1.2%) was calcium phosphate calculi. The most frequently associated comorbidity was hypertension (17.9%). The majority (78.5%) had a stone removal through a ureteroscopy and 8.2% by percutaneous nephrolithotomy (PCNL). The mean stone size was 12.2 ± 9.91 mm, with a mean stone Hounsfield unit (HU) of 789.9. The mean urinary PH at stone incident was 6.77, and the mean creatinine level was 92.4mmol.

Conclusion

This study showed that males were more affected by urolithiasis, compared to females in the Eastern Region. Furthermore, calcium oxalate was the predominant type. These findings are consistent with the literature and they highlighted the necessity for further studies in this area, to provide insight into the pathophysiology and incidence of renal calculi for improving patient care.

Ethnomedicinal Plants Used for Treatment of Urolithiasis in India: A Review

Background:

The kidney stone is the most commonly observed and painful disease of the urinary tract in human being. Numerous intrinsic and extrinsic factors are responsible for the formation of kidney stone, for instance, age, sex, heredity (intrinsic factors) and climate, dietary, geography, mineral composition, and water intake (extrinsic factors). The kidney stones are categorized into calcium, struvite or magnesium ammonium phosphate, uric acid or urate, cystine and other types of stones based on chemical composition and pathogenesis. Due to the multifactorial nature of kidney stone disease, the patient may need to rely on complex synthetic medication. However, in ancient Indian history, there are several pieces of evidence where natural resources such as plants were used to remediation this lethal disease.

Objective:

The present review attempts to provide exhaustive information of ethnomedicinal and ethnopharmacological information of medicinal plants used for kidney stone in India.

Result:

Hitherto, there are a total of 258 ethnomedicinal plants from 90 different families reported using for kidney stone application. The majority of the plant species are associated with three important families: Asteraceae, Amaranthaceae, and Fabaceae. Most of the plants are from Andhra Pradesh (43 plants), followed by East Bengal (38), Jammu & Kashmir (36), Uttarakhand (31), Panjab (27), Mizoram (23), Karnataka (20), Maharashtra (20) and Assam (18). The commonly used plant parts for the herbal preparation are roots (21.22 %) followed by leaves/leaf (20.15 %), and sometimes complete plant (17.77 %) is used. The most commonly used method for the formulation is decoction (46.41 %) followed by powder (18.66 %) and then extracts (15.78 %) of different aerial and non-aerial parts of the plant. To date, the in-vitro and in-vivo activities against the kidney stone assessed for more than sixty ethnomedicinal plants.

Conclusion:

The present review epitomizes the ethnomedicinal information of medicinal plants used for kidney stone and pharmacological evidence for anti-urolithiasis activity. Most reported medicinal plants are not yet scientifically explored and need immediate attention before we lose some important species due to excessive deforestation for farming and industrial needs.

Numerical characterization of astronaut CaOx renal stone incidence rates to quantify in-flight and post-flight relative risk

Changes in urine chemistry potentially alter the risk of renal stone formation in astronauts. Quantifying spaceflight renal stone incidence risk compared to pre-flight levels remains a significant challenge for assessing the appropriate vehicle, mission, and countermeasure design. A computational biochemistry model representing CaOx crystal precipitation, growth, and agglomeration is combined with a probabilistic analysis to predict the in- and post-flight CaOx renal stone incidence risk ratio (IRR) relative to pre-flight values using 1517 astronaut 24-h urine chemistries. Our simulations predict that in-flight fluid intake alone would need to increase from current prescriptions of 2.0–2.5 L/day to ~3.2 L/day to approach the CaOx IRR of the pre-flight population. Bone protective interventions would reduce CaOx risk to pre-flight levels if Ca excretion alone is reduced to <150 mg/day or if current levels are diminished to 190 mg/day in combination with increasing fluid intake to 2.5–2.7 L/day. This analysis provides a quantitative risk assessment that can influence the critical balance between engineering and astronaut health requirements.

Probiotics in the Prevention of the Calcium Oxalate Urolithiasis

Nephrolithiasis ranks third among urological diseases in terms of prevalence, making up about 15% of cases. The continued increase in the incidence of nephrolithiasis is most probably due to changes in eating habits (high protein, sodium, and sugar diets) and lifestyle (reduced physical activity) in all developed countries. Some 80% of all kidney stones cases are oxalate urolithiasis, which is also characterized by the highest risk of recurrence. Frequent relapses of nephrolithiasis contribute to severe complications and high treatment costs. Unfortunately, there is no known effective way to prevent urolithiasis at present. In cases of diet-related urolithiasis, dietary changes may prevent recurrence. However, in some patients, the condition is unrelated to diet; in such cases, there is evidence to support the use of stone-related medications. Interestingly, a growing body of evidence indicates the potential of the microbiome to reduce the risk of developing renal colic. Previous studies have primarily focused on the use of Oxalobacterformigenes in patients with urolithiasis. Unfortunately, this bacterium is not an ideal probiotic due to its antibiotic sensitivity and low pH. Therefore, subsequent studies sought to find bacteria which are capable of oxalate degradation, focusing on well-known probiotics including Lactobacillus and Bifidobacterium strains, Eubacterium lentum, Enterococcus faecalis, and Escherichia coli.

Perceptions of dietary factors promoting and preventing kidney stones among Taif City Population - A cross-sectional study

Background and Aim:

Methods:

Results:

Conclusion:

Epidemiological trends of urinary tract infections, urolithiasis and benign prostatic hyperplasia in 203 countries and territories from 1990 to 2019

BACKGROUND

Urinary tract infections (UTI), urolithiasis, and benign prostatic hyperplasia (BPH) are three of the most common nonmalignant conditions in urology. However, there is still a lack of comprehensive and updated epidemiological data. This study aimed to investigate the disease burden of UTI, urolithiasis, and BPH in 203 countries and territories from 1990 to 2019.

METHODS

Data were extracted from the Global Burden of Disease 2019, including incident cases, deaths, disability-adjusted life-years (DALYs) and corresponding age-standardized rate (ASR) from 1990 to 2019. Estimated annual percentage changes (EAPC) were calculated to evaluate the trends of ASR. The associations between disease burden and social development degrees were analyzed using a sociodemographic index (SDI).

RESULTS

Compared with 1990, the incident cases of UTI, urolithiasis, and BPH increased by 60.40%, 48.57%, and 105.70% in 2019, respectively. The age-standardized incidence rate (ASIR) of UTI increased (EAPC = 0.08), while urolithiasis (EAPC = - 0.83) and BPH (EAPC = - 0.03) decreased from 1990 to 2019. In 2019, the age-standardized mortality rate (ASMR) of UTI and urolithiasis were 3.13/100,000 and 0.17/100,000, respectively. BPH had the largest increase (110.56%) in DALYs in the past three decades, followed by UTI (68.89%) and urolithiasis (16.95%). The burden of UTI was mainly concentrated in South Asia and Tropical Latin America, while the burden of urolithiasis and BPH was recorded in Asia and Eastern Europe. Moreover, the ASIR and SDI of urolithiasis in high-SDI regions from 1990 to 2019 were negatively correlated, while the opposite trend was seen in low-SDI regions. In 2019, the ASIR of UTI in females was 3.59 times that of males, while the ASIR of urolithiasis in males was 1.96 times higher than that in females. The incidence was highest in the 30-34, 55-59, and 65-69 age groups among the UTI, urolithiasis, and BPH groups, respectively.

CONCLUSION

Over the past three decades, the disease burden has increased for UTI but decreased for urolithiasis and BPH. The allocation of medical resources should be based more on the epidemiological characteristics and geographical distribution of diseases.

Association of lead and cadmium exposure with kidney stone incidence: A study on the non-occupational population in Nandan of China

BACKGROUND

Environmental lead (Pb) and cadmium (Cd) pollution has been considered a risk factor in the etiology of kidney stones. However, the association between Pb and Cd exposure and kidney stone incidence has yet to be determined.

OBJECTIVES

This study aimed to determine a possible the association between kidney stones with Pb and Cd exposure (alone or combined) in a non-occupational population.

METHODS

Pb and Cd contaminations in soil-plant system were determined by flame atomic absorption spectrophotometry. Health risk assessment of dietary Pb or Cd intake from rice and vegetables were calculated. Kidney stones were diagnosed with urinary tract ultrasonography. Urinary cadmium (UCd) and blood lead (BPb) levels were determined by graphite-furnace atomic absorption spectrometry. Multivariate logistic regression models were constructed.

RESULTS

The hazard indexes (HI) of Pb and Cd were 7.91 and 7.31. The odds ratio (OR) was 2.83 (95 %CI:1.38-5.77) in males with high BPb (BPb ≥ 100 μg/L), compared with those with low BPb (BPb＜100 μg/L). Compared to those with low BPb and low UCd (BPb＜100 μg/L and UCd＜2 μg/g creatinine), the ORs were 2.58 (95 % CI:1.17-5.70) and 3.43 (95 % CI:1.21-9.16) in females and males with high BPb and high UCd (BPb ≥100 μg/L and UCd ≥2 μg/g creatinine), respectively. The OR was 3.16 (95 % CI:1.26-7.88) in males with high BPb and low UCd (BPb ≥ 100 μg/L and UCd ＜2 μg/g creatinine), compared to those with low BPb and low UCd.

CONCLUSIONS

Kidney stones incidence was increased by high Pb exposure in males, and by Pb and Cd co-exposure in males and females.

Is primary ureteroscopy an alternative to emergency stenting in terms of quality and cost?

Introduction

The aim of this article was to investigate quality and cost benefits of managing urolithiasis by primary ureteroscopic procedures (P-URS) during index admission to hospital. With the rise in prevalence of urolithiasis, the focus has shifted to manage these patients during their first admission rather than using temporary measures like emergency stenting (ES) or nephrostomies which are followed by deferred ureteroscopic procedures (D-URS). We compared results of P-URS, D-URS and ES procedures in terms of quality and cost benefits.

Material and methods

Data was collected retrospectively for all P-URS, D-URS and ES procedures performed during year 2019. A total of 85 patients underwent ES while as 138 patients underwent elective URS (26 had P-URS and 112 had D-URS). The quality assessment was based in relation to patient factors including- number of procedures per patient, number of days spent at hospital, number of days off work. Cost analysis included theatre and hospital stay expenses, loss of working days.

Results

This study revealed that the average hospital stay of patients on index admission who had a ES was 1.35 days (Total 3.85) and who had P-URS was 1.78 days (Total 2.78). Overall, additional expenditure in patients who did not undergo primary URS was in the range of 1800-2000€ (excluding loss of work for patients, who needed to return for multiple procedures).

Conclusions

We conclude approach of P-URS and management of stones in index admission is very effective in both improving quality of patients as well as bringing down cost expenditure effectively.

Retrospective epidemiological study of urolithiasis in western Algeria over a period of 50 years

Background

Urolithiasis is a pathology that changes with time and with the evolution of human societies. The prevalence of this pathology has gradually increased during the last decades, especially because of dietary changes.

Methods

This work is a retrospective descriptive epidemiological study of the temporal type carried out at the level of the urology service of the University Hospital Center of Oran between the first January 1965 and December 31, 2014. The objectives of this work are to study the epidemiological profile of urolithiasis and to determine the evolutionary trend of the disease over time.

Results

This study confirms some current data in the direction of an increase in surgical activity concerning the treatment of urinary stones. The analysis over time shows us a significant decrease (p < 0.01) in the male predominance between 1965 and 2014 with a M/F ratio which decreased from 3.09 to 1.82, as well as an increase in the average age, rising from 28.8 years in the period 1965–1974 to 48.3 years between 2005 and 2014.

Conclusion

The analysis of epidemiological data is essential to better evaluate the evolution of the urolithiasis disease, which was affirmed in our study, where a constant evolution of the characteristics of the disease was revealed, testifying the change of the socio-economic level in Algeria.

Effect of antibiotic treatment on Oxalobacter formigenes colonization of the gut microbiome and urinary oxalate excretion

The incidence of kidney stones is increasing in the US population. Oxalate, a major factor for stone formation, is degraded by gut bacteria reducing its intestinal absorption. Intestinal O. formigenes colonization has been associated with a lower risk for recurrent kidney stones in humans. In the current study, we used a clinical trial of the eradication of Helicobacter pylori to assess the effects of an antibiotic course on O. formigenes colonization, urine electrolytes, and the composition of the intestinal microbiome. Of 69 healthy adult subjects recruited, 19 received antibiotics for H. pylori eradication, while 46 were followed as controls. Serial fecal samples were examined for O. formigenes presence and microbiota characteristics. Urine, collected serially fasting and following a standard meal, was tested for oxalate and electrolyte concentrations. O. formigenes prevalence was 50%. Colonization was significantly and persistently suppressed in antibiotic-exposed subjects but remained stable in controls. Urinary pH increased after antibiotics, but urinary oxalate did not differ between the control and treatment groups. In subjects not on antibiotics, the O. formigenes-positive samples had higher alpha-diversity and significantly differed in Beta-diversity from the O. formigenes-negative samples. Specific taxa varied in abundance in relation to urinary oxalate levels. These studies identified significant antibiotic effects on O. formigenes colonization and urinary electrolytes and showed that overall microbiome structure differed in subjects according to O. formigenes presence. Identifying a consortium of bacterial taxa associated with urinary oxalate may provide clues for the primary prevention of kidney stones in healthy adults.

Incidence of nephrolithiasis after bladder augmentation in people with spina bifida

INTRODUCTION

Risks of nephrolithiasis after bladder augmentation in people with spina bifida (SB) remain unclear. Annual incidence of nephrolithiasis in the general population is 0.01% for 10-14 years old, 0.07% for 15-19 years old and 0.2% for 20-24 years old. Our aim was to assess the incidence and risk factors of nephrolithiasis in SB patients after augmentation.

METHODS

Patients with SB and augmentation followed at our institution were retrospectively reviewed (born ≥1972, surgery 1979-2019). Patients were screened annually with renal bladder ultrasound and abdominal radiograph. Main outcome was nephrolithiasis treatment. Kaplan-Meier survival and Cox proportional hazards analysis were used. Possible predictors were assessed using stepwise forward selection (variables with p < 0.1 on univariate analysis included in multivariate analysis).

RESULTS

427 patients with SB and augmentation were included (51.8% female, 74.9% shunted). Median age at augmentation was 8.5 years (median follow-up: 12.4 years, ileum segment: 81.0%, bladder neck procedure: 60.7%, urinary channel: 74.2%) and 28.8% developed bladder stones. Overall, 47 (11.0%) patients were treated for nephrolithiasis. After correction for differential follow-up, nephrolithiasis was treated in 7.3% at 10 years, 13.2% at 15 years, and 18.0% at 20 years (Figure). Patients presented with either a urinary tract infection (46.8%), on screening (44.7%), or pain (8.5%). Stones were treated percutaneously, endoscopically or by ESWL (63.8%/34.0%/10.7%, respectively). Most were calcium stones (58.3%). On multivariate analysis, compared to younger patients, patients augmented at ≥10 years of age had 1.84 times the risk of nephrolithiasis (p = 0.01). Nephrolithiasis was more common in those who developed bladder stones (HR = 3.00, p < 0.0001). Among those with both renal and bladder stones, bladder stones typically preceded nephrolithiasis (55.2%), were treated concurrently (31.0%) and 13.8% occurred after nephrolithiasis. Gender, wheelchair use, bowel segment used, MACE and skeletal fractures were not associated with higher nephrolithiasis risk (p ≥ 0.11).

DISCUSSION

This study of a large cohort of SB patients with long-term follow-up highlights that the risk of nephrolithiasis is cumulative and related to bladder stone formation, age at augmentation and time since augmentation. An association with bladder stones suggests potential shared metabolic causes. The study's retrospective design likely led to underestimating the risk of nephrolithiasis by not capturing spontaneously passed stones.

CONCLUSION

Approximately 1% of patients with SB develop nephrolithiasis annually after augmentation. Close long-term surveillance after augmentation is strongly indicated, as nephrolithiasis incidence in augmented patient with SB is at least 10 times higher than general population. Patients with bladder stones are especially at risk.

The Molecular Aspect of Nephrolithiasis Development

Urolithiasis is the third most common urological disease after urinary tract infections and prostate diseases, and it is characterised by an occurrence rate of about 15%, which continues to rise. The increase in the incidence of kidney stones observed in recent decades, is most likely caused by modifications in dietary habits (high content of protein, sodium and sugar diet) and lifestyle (reduced physical activity) in all industrialised countries. Moreover, men are more likely than women to be diagnosed with kidney stones. A growing body of evidence suggests that inflammation, oxidant-antioxidant imbalance, angiogenesis, purine metabolism and urea cycle disorders may play a crucial role in nephrolithiasis development. Patients with urolithiasis were characterised by an increased level of reactive oxygen species (ROS), the products of lipid peroxidation, proinflammatory cytokines as well as proangiogenic factors, compared to controls. Furthermore, it has been shown that deficiency and disorders of enzymes involved in purine metabolism and the urea cycle might be causes of deposit formation. ROS generation suggests that the course of kidney stones might be additionally potentiated by inflammation, purine metabolism and the urea cycle. On the other hand, ROS overproduction may induce activation of angiogenesis, and thus, allows deposit aggregation.

The new patterns of nephrolithiasis: What has been changing in the last millennium?

Nephrolithiasis has been increasing over the last millennium. Although early epidemiologic studies have shown that kidney stones were two to three times more frequent in males than in females, recent reports have suggested that this rate is decreasing. In parallel a dramatic increase of nephrolithiasis has also been observed among children and adolescents. Furthermore, epidemiologic studies have shown a strong association between metabolic syndrome (Mets) traits and kidney stone disease. Patients with hypertension have a higher risk of stone formation and stone formers are predisposed to develop hypertension compared to the general population. An incidence of nephrolithiasis greater than 75% has been shown in overweight and obese patients compared to those of normal weight. It has also been reported that a previous diagnosis of diabetes mellitus increases the risk of future nephrolithiasis. Additionally, an association between metabolic syndrome and uric acid stone formation has been clearly recognized. Furthermore, 24-h urinary metabolic abnormalities have been decreasing among patients with nephrolithiasis over the last decades. Finally, nephrolithiasis could cause chronic kidney disease (CKD) and end stage renal disease (ESRD), especially in women and overweight patients. According to these observations, a better understanding of these new features among stone former patients may be required. Hence, the recognition and the correction of metabolic disorders could help not only to reduce the primary disease, but also stone recurrence.

Emergent urinary decompression in acute stone-related urinary obstruction: A systematic review and meta-analysis

Introduction:

Emergent urinary decompression through percutaneous nephrostomy (PCN) or ureteric stent (URS) remains a mainstay in the management of urethral calculi-related obstruction with associated signs of infection or renal injury. Available evidence has shown similar performance, and current guidelines endorse both treatment strategies.

Methods:

A systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analysis criteria up until August 2020. Studies included data on stone size and location, operative time, complications, length of stay, analgesic consumption, quality of life (QoL), and clinical outcomes between URS and PCN.

Results:

Ten studies with a total population of 772, of which 420 were treated with URS and 352 with PCN, were included. No statistical difference in operative time between both techniques was found. Nevertheless, length of stay in PCN was longer than in USR, with a mean difference of −1.87 days ((95% CI −2.69 to −1.06), Z=4.50, p=0.00001). No differences were found in the time to normalization of temperature or white blood cell counts. There were no significant differences in success rates, with an overall odds ratio (OR) of 0.60 ((95% CI 0.26 to −1.40), Z=1.17, p=0.24), or spontaneous passage after emergent drainage between groups. Complication rates ranged from 5% to 25% in URS and from 0% to 38% in PCN. In the studied population, out of the 157 patients from four studies describing complications, only 5% of URS procedures presented complications compared to 2% in PCN, showing a relatively low complication rate for either group (OR=2.07 (95% CI 0.89–4.84), Z=1.68, p=0.09). Differences in QoL were not significant.

Conclusion:

Both methods are equally effective, with no clear advantage for PCN over URS.

Level of evidence:

IV

Comparison of the Effects of Treadmill Running and Rope Jumping on the Excretion of Mass-Like Urinary Stones Following Extracorporeal Shock Wave Lithotripsy

Background: Extracorporeal shock wave lithotripsy (ESWL) is an effective and relatively safe method for crushing urinary tract stones Objectives: The purpose of this study was to compare the effect of running on treadmill and rope jumping exercises on the excretion of mass-like urinary stones following ESWL in the patients referred to the Asia clinic in the city of Ilam. Methods: This was a quasi-experimental study. The subjects were selected by the convenience sampling method and randomly divided into three groups, including control, treadmill running, and rope jumping (n = 50 per group). Data were collected by a questionnaire to record the sonographic characteristics of the stones before and after lithotripsy and analyzed by SPSS software version 24 using Chi-square, unpaired t-test, and one-way ANOVA at the significance level of 5%. Benieman-Hashberg method was used to correct multiple comparisons. Results: There was a significant difference in the number of excreted stones comparing the control, treadmill running, and rope jumping groups (F = 8.851, P = 0.002). There were significant differences between the control and both treadmill running (P = 0.038) and rope jumping (P = 0.002) groups regarding the rate of stone excretion. However, there was no significant difference between the treadmill running and rope jumping groups regarding the rate of stone excretion (P = 0.293). Conclusions: Rope jumping and treadmill running exercises can help to better and faster expel kidney stones, depending on their location, after lithotripsy.

Gender-related differences in the risk factors for repeat stone surgery

Our objective was to analyze and compare the associations between potential risk factors for nephrolithiasis and repeat stone surgery in male and female patients. We retrospectively analyzed 1970 patients who had stone surgery at our institution in the period from January 2009 to May 2017, were older than 18 years and had at least 12 months of postoperative follow-up. Our definition of surgical recurrence included repeat surgery on the same renal unit or on the opposite renal unit if the original imaging did not demonstrate significant stones on that side. Uni- and multivariate Cox regression models were built for each gender. We also explored the interactions between gender and other patient's characteristics in their effect on the risk of recurrence. Ureteroscopy was the most common treatment modality for both first (83%) and repeat (87%) procedures. Over a mean follow-up of 4.3 years (median 3.8, interquartile range 2.2-6.0), 413 (21.0%) patients had a surgical recurrence. In multivariate analyses, hypertension, diabetes, Caucasian race and younger age (less than 60 years) were significantly associated with the risk of surgical recurrence only in females. Interaction between these characteristics and gender was significant indicating a larger effect on the risk of surgical recurrence in females compared to males. Our study demonstrated a number of differences in the predictors of repeat surgery for nephrolithiasis between males and females. If confirmed by future studies these differences may be helpful for optimizing nephrolithiasis prevention efforts.

Changing in gender prevalence of nephrolithiasis

Although nephrolithiasis is a more common disease in men rather than women, several studies over the last decades show that the male to female ratio 3:1 is narrowing. These finding may be associated to modified risk factors for stone formation between females and males. Changes in lifestyle and increasing obesity in women may play a role in shifting of gender disparity. Furthermore, recent studies have demonstrated an increase of kidney stones in women which have necessitated emergency department visits (ED). Therefore, females show a greater percentage of mortality rate if compared to males, especially if stone disease is associated to urosepsis and requires the admission to the Intensive Care Unit (ICU). This article reviews recent insights into changing gender prevalence in urinary calculi and into identifying the relation between gender and risk factors for stone disease, that in case of severe urosepsis might also lead to mortality.

Urinary Calculi: A Microbiological and Biochemical Analysis at a Tertiary Care Hospital in Eastern Nepal

Background

The occurrence of urinary tract infection in presence of urolithiasis is frequently noted; however, microbial agents of urolithiasis and their antimicrobial susceptibility patterns remain underinvestigated. This study aimed to identify the microorganisms isolated from urine and stone matrices to determine their antimicrobial susceptibility, to find the association between the pathogens of urine and stone matrices, and to perform the biochemical analysis of stones.

Methods

A total of 88 cases of urolithiasis admitted for elective stone removal at Department of surgery, B.P. Koirala Institute of Health Sciences (BPKIHS), were enrolled. Preoperative urine culture and postoperative stone culture were performed. Isolation, identification, and AST were done by the standard microbiological technique. Further qualitative biochemical analysis of stones was also attempted.

Result

Among 88 stone formers recruited, culture of urine, whole stone, and nidus yielded the growth of bacteria 44, 32, and 30, respectively. Bacteria isolated from urine culture correlated with those from stone matrices with a sensitivity of 90%, specificity of 79.69%, PPV of 63.64%, and NPV of 95.45%. Escherichia coli (46.7%) was the most common bacteria followed by Klebsiella pneumoniae (16.7%) and Proteus mirabilis (13.3%) from urine and stone cultures. Almost all the uropathogens isolated were susceptible to commonly used antibiotics. Calcium oxalate (84.1%) was common biochemical constituent found in stone formers followed by calcium oxalate + phosphate (8%).

Conclusions

The association of microorganism isolated from urine and nidus culture was significant that can predict the source of infective stone; however, in some cases, microorganisms and the antimicrobial susceptibility pattern from urine and nidus were different. This study emphasizes the use of appropriate antimicrobial agents to prevent the regrowth of residual stones and minimize the risk of infectious complications after surgical removal of stones.

Prevalence and Trends in Kidney Stone Among Adults in the USA: Analyses of National Health and Nutrition Examination Survey 2007-2018 Data

BACKGROUND

The contemporary prevalence and trends of kidney stones are not clear.

OBJECTIVE

To evaluate the gender-specific prevalence and trends in kidney stones among the US population.

DESIGN, SETTING, AND PARTICIPANTS

Data on self-reported history of kidney stones from 34 749 participants aged ≥20 yr from the National Health and Nutrition Examination Survey (NHANES) were analyzed.

INTERVENTION

Six 2-yr study cycles (2007-2008 to 2017-2018) of nationally representative series of surveys evaluated the health status of the US population.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Weighted prevalence estimates of kidney stones and 95% confidence intervals (CIs) were calculated in each study cycle. Multivariable-adjusted logistic regression models were used to investigate the temporal trends.

RESULTS AND LIMITATIONS

In the 2017-2018 cycle, the prevalence of kidney stones was 10.9% (CI: 9.3-12.7) in men as compared with 9.5% (CI: 8-11.2) in women. The prevalence of kidney stones increased steadily from 6.5% in the 2007-2008 cycle to 9.4% in the 2017-2018 cycle (p_trend = 0.001) among women but not among men (p_trend = 0.1). These trends remained after adjusting for sociodemographic correlates in both genders. Sensitivity analyses further adjusting for dietary information held the same results in trends (men: p_trend = 0.15; women: p_trend = 0.001). Non-Hispanic white ethnicity, obesity, gout, history of two or more pregnancies, menopause, and using female hormones were associated with a higher prevalence of kidney stones. The main limitation is the cross-sectional design of the study.

CONCLUSIONS

Although kidney stones are more common in men than in women in the USA, the gender gap in kidney stone prevalence appears to be closing in the past decade. Kidney stones are consistently higher among non-Hispanic white and obese, and women who have had multiple pregnancies or have used female hormone therapy.

PATIENT SUMMARY

The prevalence of kidney stones remains higher in adult US men than in women, but the trend has been increasing only in women, closing the gender gap in kidney stone prevalence.

Biochemical Alterations in Patients with Oxalocalcic Lithiasis, the Influence of Sex, Age, and Body Mass Index

Background: Urolithiasis is a disorder that has a high prevalence in the population. Also, lithiasic patients have biochemical alterations that predispose them to the formation of stones. The knowledge of these alterations may be useful for future preventive interventions. Objectives: The objectives were to describe the metabolic characteristics of patients with oxalocalcic lithiasis, identifying the most frequent biochemical alterations, and their variation with different demographic variables. In this way, we can prevent the formation of the lithiasis before it appears, instead of treating it once established. Methods: A descriptive cross-sectional study of serum and 24 hour-urine parameters in patients with oxalocalcic lithiasis was performed. The most frequent biochemical alterations were described, and their association with age, sex, and body mass index (BMI) were assessed. Results: In this study, 100% of the 151 patients had biochemical alterations, the most frequent being hypocitraturia (84.7%), hypercalciuria (51.7%), and urinary pH decrease (44.4%). There were differences according to sex, age, and BMI with regard to the biochemical alterations. Hypouricemia, hypouricosuria, hypophosphaturia and hypomagnesuria were more frequent in women. Men had a higher percentage of hyperzinquemia, hyperphosphaturia, and excess of urinary urea. Urine density in men was slightly higher than in women. A higher percentage of hyperphosphaturia, excess urinary urea, and excess of serum urea was found in overweight patients. Patients not overweight showed a higher percentage of hypouricemia and hypomagnesuria. Urinary density was slightly higher in overweight patients. Urinary volume was higher in middle-aged subjects. Conclusions: Patients with oxalocalcic lithiasis have biochemical alterations that may predispose to stone formation. These alterations vary with sex, age, and BMI.

Relationship of Cholelithiasis and Urolithiasis with Methylenetetrahydrofolate Reductase Polymorphisms

AIM

To investigate the relationship of cholelithiasis and urolithiasis with Methylenetetrehydrofolate Reductase (MTHFR) polymorphism(s) in patients with poor obstetric history to search whether they are risk factors for adverse pregnancy outcome.

MATERIALS AND METHOD

This study is consisted of 94 patients with poor obstetric history. Patients were evaluated in terms of the presence of cholelithiasis and urolithiasis in association with MTHFR polymorphism(s). Additional laboratory tests including homocysteine measurements were also performed. ROC analysis for assessing the performance of blood homocysteine level in predicting the presence of cholelithiasis and urolithiasis were also performed.

RESULTS

Patients were divided into three groups such as cholelithiasis group (n = 9, 9.6%), urolithiasis group (n = 18, 19.1%) and control group (n = 67, 71.3%). Groups did not differ in term of age and Beksac obstetrics index (BOI) which is "[living child+(π/10)]/gravidity." The rate of the presence of MTHFR polymorphisms were 88.9% (8/9), 88.9% (16/18) and 43.3% (29/67) in cholelithiasis, urolithiasis and control groups respectively. Median homocysteine levels were found to be 13.1, 11.6 and 7.2 micromol/lt for the groups respectively. Statistically significant differences were found for MTHFR polymorphism rates and homocysteine levels (<0.001 for both). According to ROC analysis, 10.9 mcmol/L (88.9% sensitivity, 89.6% specificity) and 9.25 mcmol/L (83.3% sensitivity, 73.1% specificity) were determined to be cutoff values of homocysteine for cholelithiasis and urolithiasis respectively.

CONCLUSION

More frequent MTHFR polymorphisms are observed in women with a clinical history of gall or renal stones. Thus, screening of these patients may be benefical for the approprate management of their subsequent pregnancies.

Sex differences in the therapy of kidney and ureteral stones

PURPOSE OF REVIEW

Better understanding of sex differences affecting urolithiasis may help us offer tailored treatment strategies to our patients.

RECENT FINDINGS

The incidence of urolithiasis is increasing and the male-to-female ratio has decreased from 3 : 1 to 1.3 : 1 between 1970 and 2000. In women, obesity has a larger effect on the risk of developing urolithiasis [odds ratio (OR) 1.35; 95% confidence interval (CI): 1.33-1.37] compared with men (OR 1.04; 95% CI: 1.02-1.06). Urolithiasis is a risk factor for coronary artery disease in men (risk ratio = 1.23; 95% CI: 1.02-1.49) and for stroke in women (risk ratio = 1.12; 95% CI: 1.03-1.21). Women tolerate cystoscopic stent removal and shock wave lithotripsy better than men. For shock wave lithotripsy menopaused women have reported lower visual analog scale scores than menstruating women (P < 0.001). Female sex was an independent predictor of stone impaction (OR 1.15; 95% CI: 1.03-1.27) and postoperative sepsis after ureteroscopy (OR 2.31; 95% CI: 1.14-4.37).

SUMMARY

The sex gap in urolithiasis is closing. The changing role of women in society and dietary habits can be responsible for this epidemiologic shift. Women show a higher threshold for pain during urologic procedures, but they suffer from infectious complications more than men. Urolithiasis is a risk factor for cardiovascular events in both sexes.

Association between calcium-sensing receptor (CaSR) R990G, CaSR A986S, and CaSR Q1011E gene polymorphisms and the risk of urolithiasis: a meta-analysis

Backgrounds

In the last two decades, studies have been widely carried out to assess the association between single-nucleotide polymorphisms (SNPs) of calcium-sensing receptor (CaSR) gene in exon 7 and the risk of urolithiasis. However, inconsistency across the studies was reported. Therefore, our current study aimed to perform a meta-analysis concerning the association between the risk of urolithiasis and the gene polymorphisms of CaSR R990G, CaSR A986S, and CaSR Q1011E.

Methods

Published papers from PubMed, Embase, Cohcrane, and Web of science were included for the study, and they were analyzed using fixed or random effect model.

Results

A total of 11 papers consisting of eight papers evaluating CaSR R990G, nine papers evaluating CaSR A986S, and five papers evaluating CaSR Q1011E were included in our analysis. Our pooled calculation found that protective effect against urolithiasis was observed in R allele and RR genotype of CaSR R990G and A allele and AA genotype of CaSR A986S. Conversely, increased susceptibility to urolithiasis was found in G allele and RG genotype of CaSR R990G and S allele of CaSR A986S. Interestingly, our findings in sub-group analysis confirmed that the correlation between CaSR R990G and urolithiasis was found in Caucasian population. Meanwhile, in Asian population, the association was observed in CaSR A986S.

Conclusions

CaSR R990G and CaSR A986S, but not CaSR Q1011E, are associated with the risk of urolithiasis.

Trends in urinary calculi composition from 2005 to 2015: a single tertiary center study

The goal of this study was to investigate recent changes in stone composition and patient demographics to identify factors influencing stone formation for the purpose of reducing the incidence of urolithiasis and preventing stone recurrence. This retrospective analysis includes patients who underwent percutaneous nephrolithotripsy or ureteroscopy at our institution from 2005 to 2015. Northwestern Medicine Enterprise Data Warehouse was used to retrieve demographic information and stone composition analyses. The composition of mixed stones containing uric acid (UA) and calcium oxalate monohydrate (COM) was analyzed further. Chi-squared tests were used for categorical variables and logistic regression was used to assess trends. From 2005 to 2015, 5268 stones were treated. COM was predominant in 42.2% and only 16.6% were pure. The male/female ratio decreased significantly from 1.8 to 1.08 and patient age increased (p < 0.001) with 45.6% of patients being 60 or older in 2015. Females formed more CO dihydrate (COD; p = 0.008) and struvite (p = 0.001) overall. The incidence of COM (p = 0.007) and UA (p < 0.001) rose significantly in men whereas both sexes saw a decrease in carbonate apatite (CA; p < 0.001). COM increased considerably from 12 to 75% amongst mixed stones with UA over the 11-year span. We concluded that stone formers have become older and more gender-equal. The increase in female patients parallels the increase in female obesity in the US. The rising predominance of COM, including when mixed with UA, and the scarcity of pure stones indicates it may be necessary to develop new approaches to managing and preventing urolithiasis.