Clinical manifestations and renal pathology of ethylene glycol.

Ethylene glycol (EG) poisoning is a critical medical emergency often associated with suicide attempts in adults. EG is metabolized by alcohol dehydrogenase, leading to the formation of toxic metabolites that cause metabolic acidosis, renal failure, hypocalcemia, aciduria, and disorders of the central nervous and cardiovascular systems. Calcium oxalate, a metabolite of EG, contributes to acute tubular necrosis. Despite limited reports on human renal pathology, we present a case detailing renal pathology following EG ingestion. A 44-year-old male, admitted due to loss of consciousness, had ingested a lethal dose of EG. Blood tests indicated metabolic acidosis, while urinary examination revealed calcium oxalate crystals. Continuous renal replacement therapy corrected the acidosis; however, nephrogenic diabetes insipidus subsequently developed. A renal biopsy on day 31 revealed calcium oxalate crystal deposition and tubulointerstitial damage. Notably, various stages of crystal deposition, adherence, and degradation were observed. This case underscores the importance of considering EG poisoning in cases of unexplained metabolic acidosis and renal dysfunction, with renal biopsy serving as a valuable diagnostic tool. Understanding the renal effects of EG is essential for timely intervention and effective management of poisoning cases.

Machine learning and 4D-LFQ quantitative proteomic analysis explore the molecular mechanism of kidney stone formation.

Background: Nephrolithiasis, a common and chronic urological condition, exerts significant pressure on both the general public and society as a whole. The precise mechanisms of nephrolith formation remain inadequately comprehended. Nevertheless, the utilization of proteomics methods has not been employed to examine the development of renal calculi in order to efficiently hinder and manage the creation and reappearance of nephrolith. Nowadays, with the rapid development of proteomics techniques, more efficient and more accurate proteomics technique is utilized to uncover the mechanisms underlying diseases. The objective of this study was to investigate the possible alterations of HK-2 cells when exposed to varying amounts of calcium oxalate (CaOx). The aim was to understand the precise development of stone formation and recurrence, in order to find effective preventive and treatment methods. Methods: To provide a complete view of the proteins involved in the development of nephrolithiasis, we utilized an innovative proteomics method called 4D-LFQ proteomic quantitative techniques. HK-2 cells were selected as our experimental subjects. Three groups (n = 3) of HK-2 cells were treated with intervention solutions containing 0 (negative control, NC), 1 mM, and 2 mM CaOx, respectively. For the proteins that showed differential expression, various analyses were conducted including examination of Gene Ontology (GO), Clusters of Orthologous Groups of proteins (KOG), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, enrichment analysis of protein domains, and hierarchical clustering analysis. The STRING database was used to identify the interaction network of the chosen proteins. Candidate proteins were validated using parallel reaction monitoring (PRM) in the end. Results: All three groups verified the repeatability of samples. According to the results of 4D-LFQ proteomic quantitative analysis, there were 120, 262, and 81 differentially expressed proteins (DEPs) in the 1 mM-VS-NC, 2 mM-VS-NC, and 2 mM-VS-1mM conditions, respectively. According to GO annotation, the functional enrichment analysis indicates that the differentially expressed proteins (DEPs) were notably enriched in promoting cell migration and the extracellular matrix, among other functions. Analysis of enrichment, based on the KEGG pathway, revealed significant enrichment of DEPs in complement and coagulation cascades, as well as in ECM-receptor (extracellular matrix-receptor) interaction and other related pathways. 14 DEPs of great interest were selected as candidate proteins, including FN1, TFRC, ITGA3, FBN1, HYOU1, SPP1, HSPA5, COL6A1, MANF, HIP1R, JUP, AXL, CTNNB1 and DSG2.The data from PRM demonstrated the variation trend of 14 DEPs was identical as 4D-LFQ proteomic quantitative analysis. Conclusion: Proteomics studies of CaOx-induced HK-2 cells using 4D-LFQ proteomic quantitative analysis and PRM may help to provide crucial potential target proteins and signaling pathways for elucidating the mechanism of nephrolithiasis and better treating nephrolithiasis.

SGLT-2 inhibitors and nephrolithiasis risk: a meta-analysis.

BACKGROUND AND AIM: Sodium-glucose cotransporter (SGLT)-2 inhibitors are novel anti-diabetic medications with potential beneficial effects on cardiovascular and renal outcomes, metabolic parameters, and body weight. In addition to the beneficial effects on renal functions, including estimated glomerular filtration rate and reduction in proteinuria, recent studies have investigated the potential role of SGLT-2 inhibitor therapy on nephrolithiasis development. Nephrolithiasis, a condition affecting almost 10% of the general population at least once during a lifetime, is a common disorder with considerable risk for acute and chronic kidney injury and relatively few effective therapeutic options. MATERIALS AND METHODS: We have performed a literature search through multiple databases, including PubMed, Ovid/Medline, Web of Science, Scopus, and Cochrane Library. We have followed the systematic review and meta-analysis guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses.We have included a total of 11 635 698 patients who experienced nephrolithiasis from six clinical trials to conduct this meta-analysis study. In the pooled analysis, nephrolithiasis occurred in 1,27% of patients from the SGLT2i group (n = 739 197), compared to 1,56% of patients (n = 10 896 501) from the control arm (active control, placebo or no therapy). RESULTS: We have included a total of 11 635 698 participants who experienced nephrolithiasis from a total of six clinical studies with nephrolithiasis rates of 1,27% in the SGLT2i group (n = 739 197), compared to 1,56% in the control arm (n = 10 896 501). SGLT-2 inhibitor therapy has been associated with a lower risk for nephrolithiasis compared to placebo (OR 0.61, 95% CI, 0.53-0.70, p < 0.00001) or active therapy such as glucagon-like peptide 1 and dipeptidyl peptidase-IV inhibitors (OR 0.66, 95% CI, 0.47-0.93, p = 0.02). CONCLUSION: We have demonstrated a lower risk of nephrolithiasis risk with SGLT-2 inhibitor therapy compared to placebo or active control. Potential underlying mechanisms include osmotic diuresis leading to a reduction in the concentration of lithogenic substances, anti-inflammatory and anti-fibrotic effects, and an increase in urine pH. There is a clear need for future large-scale randomized clinical trials evaluating such associations for better understanding.

In Vitro and In Vivo Antiurolithic Effect of Betulinic Acid Obtained from Citharexylum mirianthum.

The study aimed to investigate the potential antiurolithic effects of extracts, fractions, and betulinic acid (BA) from Citharexylum mirianthum. In vitro analysis involved precipitating calcium oxalate (CaOx) crystals in urine. For in vivo studies, rats were divided into four groups: naive; vehicle; potassium citrate (KC); and BA. Urolithiasis was induced using ethylene glycol and ammonium chloride. After seven days, urine, blood, and kidney tissues were evaluated. The results showed that methanolic extract, hexane, dichloromethane, and ethyl acetate fractions, as well as BA, reduced CaOx crystal formation. In vivo, the vehicle-treated group exhibited reduced urinary volume and Na+ excretion, while the BA-treated group showed restored urinary volume and Na+ excretion similar to the naive group. BA also significantly reduced urinary monohydrate and dihydrate crystal formation, comparable to the KC group. Other urinary parameters remained unchanged, but plasma analysis revealed decreased Na+, K+, and Ca2+ in the KC group. Renal tissue analysis indicated reduced lipid hydroperoxides and increased reduced glutathione in all urolithiasis groups, with unchanged nitrite levels. BA treatment also improved renal corpuscle morphology. Overall, our findings demonstrate that treatment with BA effectively prevented kidney damage induced by EG+AC ingestion, thereby improving renal function in the urolithiasis model.

The Evolving Role of Genetic Testing in Monogenic Kidney Stone Disease: Spotlight on Primary Hyperoxaluria.

PURPOSE: Multiple factors are thought to give rise to common, recurrent kidney stone disease, but for monogenic stone disorders a firm diagnosis is possible through genetic testing. The autosomal recessive primary hyperoxalurias (PH) are rare forms of monogenic kidney stone disease. All 3 types of PH are caused by inborn errors of glyoxylate metabolism in the liver, leading to hepatic oxalate overproduction and excessive renal urinary oxalate excretion. These conditions are characterized by kidney stones, nephrocalcinosis, progressive chronic kidney disease, and kidney failure. Systemic oxalosis, the extra-renal deposition of oxalate resulting in severe morbidity and mortality, occurs in chronic kidney disease when oxalate clearance by the kidneys declines. Novel small interfering RNA-based therapeutics targeting the liver to reduce urinary oxalate excretion have been approved, introducing precision medicine to treat primary hyperoxaluria type 1. The goal of this narrative review is to address the benefits and practicalities of genetic testing for suspected monogenic kidney stone disease and the critical roles of a multidisciplinary team. MATERIALS AND METHODS: We collated our procedures, education, training, and workflows to help other clinicians integrate genetic assessment into their diagnostic routines. RESULTS: In our experience, increased access to genetic testing facilitates early detection of PH and other monogenic causes of kidney stone disease so that individualized care can be instituted promptly. CONCLUSIONS: Alongside biochemical assessments, more widespread genetic testing may ensure more timely diagnoses so that patients with suspected monogenic kidney stone disease gain access to an expanded range of services and enrollment in clinical trials and registries.

Fabrication of acoustically and physically validated artificial stones to natural kidney stones under shock waves and laser lithotripsy.

To present an efficient method for fabricating artificial kidney stones with acoustic and physical properties to assess their fragmentation efficiency under shock waves and laser lithotripsy for very hard stones. The mixture ratio of super-hard plaster and water was adjusted to produce artificial kidney stones for comparison with > 95% human genuine calcium oxalate monohydrate (COM) and uric acid (UA) stones. Acoustic and physical properties, such as wave speed, stone hardness, density, compressive strength, and stone-free rates under shock-wave and laser lithotripsy, were assessed. The longitudinal wave speed of artificial stones prepared at a plaster-to-water ratio of 15:3 closely matched that of COM stones. Similarly, the transverse wave speed of artificial stones prepared at a plaster-to-water ratio of 15:3 to 15:5 aligned with that of COM stones. Stone fragmentation using shock-wave of artificial stones with mixed ratios ranging from 15:3 to 15:5 resembled that of COM stones. The Vickers hardness was similar to that of artificial stones produced with a mixing ratio of 15:3, similar to that of COM stones, while that of artificial stones produced with a mixing ratio of 15:5 was similar to that of UA stones. Density-wise, artificial stones with mixing ratios of 15:4 and 15:5 resembled COM stones. Compressive strength test results did not confirm the similarity between natural and artificial stones. The stone fragmentation using laser showed that stones produced with higher moisture content at a mixing ratio of 15:6 were similar to COM stones. This novel method for fabricating artificial kidney stones could be used to provide reliable materials for lithotripsy research.

Mitochondrial dysfunction and NLRP3 inflammasome: key players in kidney stone formation.

The mitochondrion serves as a critical intracellular organelle, engaging in essential roles in the regulation of energy production, oxidative stress management, calcium homeostasis, and apoptosis. One such disease that has been particularly associated with these functions is kidney stone disease (KSD), specifically calcium oxalate (CaOx). It is underpinned by oxidative stress and tissue inflammation. Recent studies have shed light on the vital involvement of mitochondrial dysfunction, the nucleotide-binding domain and leucine-rich repeat containing protein 3 (NLRP3) inflammasome, endoplasmic reticulum stress and subsequent cell death in CaOx crystal retention and aggregation. These processes are pivotal in the pathogenesis of kidney stone formation. This review focuses on the pivotal roles of mitochondria in renal cell functions and provides an overview of the intricate interconnectedness between mitochondrial dysfunction and NLRP3 inflammasome activation in the context of KSD. It is essential to recognise the utmost significance of gaining a comprehensive understanding of the mechanisms that safeguard mitochondrial function and regulate the NLRP3 inflammasome. Such knowledge carries significant scientific implications and opens up promising avenues for the development of innovative strategies to prevent the formation of kidney stones.

The effect of calcium oxalate stones and uric acid stones on male sexual function.

PURPOSE: This study compared the effects of calcium oxalate stones and uric acid stones on male sexual function. METHODS: We enrolled 100 patients with ureteral stones. According to the composition of the stones, they were divided into the calcium oxalate stone group and the uric acid stone group. All patients underwent ureteroscopic holmium laser lithotripsy. General data such as age, body mass index, course of disease, stone diameter, and degree of renal hydronephrosis were compared. Sperm parameters, including sperm density, sperm viability, and sperm deformity rate, as well as International Index of Erectile Function-5 questionnaire (IIEF-5) scores, and Quality of Life (QOL) scores, were measured and compared before and 6 weeks after the surgery. RESULTS: There were no statistically significant differences in general data and sperm parameters between the two groups before the surgery (P > 0.05). However, there were significantly lower IIEF scores but significantly higher QOL scores in the uric acid stone group. In the calcium oxalate stone group, there were no statistically significant differences in sperm parameters, IIEF score, and QOL score before and after the surgery (P > 0.05). In the uric acid stone group, there were no statistically significant differences in sperm parameters before and after surgery (P > 0.05), whereas there were significantly higher IIEF scores but significantly lower QOL scores after the surgery (P < 0.05). The prevalence of erectile dysfunction (ED) in the uric acid stone group was 38.18% (21/55), which was significantly higher compared to 20.00% (9/45) in the calcium oxalate stone group (P < 0.05). The multivariate binary logistic regression analysis showed that the independent risk factor related to ED was uric acid stones (odds ratio: 2.637, 95% confidence interval 1.040-6.689, P = 0.041). No statistically significant differences were found in sperm parameters between patients with and without ED. CONCLUSION: Compared with the calcium oxalate stone group, patients with uric acid stones had a higher prevalence of ED and poorer sexual performance.

Plant-based therapies for urolithiasis: a systematic review of clinical and preclinical studies.

PURPOSE: Urolithiasis, the formation of kidney stones, is a common and severe condition. Despite advances in understanding its pathophysiology, affordable treatment options are needed worldwide. Hence, the interest is in herbal medicines as alternative or supplementary therapy for urinary stone disease. This review explores the use of plant extracts and phytochemicals in preventing and treating urolithiasis. METHODS: Following PRISMA standards, we systematically reviewed the literature on PubMed/Medline, focusing on herbal items evaluated in in vivo models, in vitro studies, and clinical trials related to nephrolithiasis/urolithiasis. We searched English language publications from January 2021 to December 2023. Studies assessing plant extracts and phytochemicals' therapeutic potential in urolithiasis were included. Data extracted included study design, stone type, plant type, part of plant used, solvent type, main findings, and study references. RESULTS: A total of 64 studies were included. Most studies used ethylene glycol to induce hyperoxaluria and nephrolithiasis in rat models. Various extraction methods were used to extract bioactive compounds from different plant parts. Several plants and phytochemicals, including Alhagi maurorum, Aerva lanata, Dolichos biflorus, Cucumis melo, and quercetin, demonstrated potential effectiveness in reducing stone formation, size, and number. CONCLUSIONS: Natural substances offer an alternative or supplementary approach to current treatments, potentially reducing pain and improving the quality of life for urolithiasis patients. However, further research is needed to clarify their mechanisms of action and optimize their therapeutic use. The potential of plant-based therapies in treating urolithiasis is promising, and ongoing research is expected to lead to treatment advancements benefiting patients globally.

Assessment of Urinary Stone Chemical Compositions and Prevalence of Metabolic Disorders Among Urolithiasis Patients in Northern Sri Lanka: A Prospective Study.

Introduction Urolithiasis, a common urological disorder affecting the global population, demonstrates geographical diversity due to factors such as water quality, climate variations, health conditions, and dietary habits. This study, conducted in Northern Sri Lanka, examines urinary stone compositions and assesses the prevalence of metabolic disorders among urolithiasis patients. Methods This prospective cross-sectional study, conducted at Jaffna Teaching Hospital, Jaffna, Sri Lanka, from July 2022 to June 2023, focused on surgically treated urolithiasis patients. Institutional ethical clearance was obtained. Patient details and investigational findings were collected through questionnaires and data extraction forms. Stone analysis utilized Fourier transform infrared spectroscopy, and a detailed metabolic evaluation of a 24-hour urine collection sample was carried out. Results This study followed 153 surgically treated urolithiasis patients, primarily male (64.3%), with a mean age of 48.64. Ureteric colic (48.4%) was common, with kidney stones (45.8%) prevalent; 57.52% had recurrent stones. Diabetes mellitus (DM; 23.5%) was the top comorbidity. Calcium oxalate monohydrate (COM) stones (78.4%) were the most frequent, followed by uric acid (12.4%). COM predominated in the 40-59 age group. There was no significant gender-stone type association. A total of 86.9% had metabolic abnormalities, notably hypocitraturia (60.1%). Moreover, 23% had both hypocitraturia and hypomagnesuria. Some metabolic disorders showed gender differences, with a marginal age-metabolic disorder association (p < 0.061). Urine oxalate levels were normal, with higher variability in males. Conclusion Middle-aged males with urolithiasis commonly presented with ureteric colic and predominantly had COM stones. Recurrent stones were common, often accompanied by metabolic abnormalities such as hypocitraturia and hypomagnesuria, with DM as the primary comorbidity.

Baicalin attenuated oxidative stress and inflammation in ethylene glycol-induced urolithiasis in adult male SD rats.

AIMS: Baicalin is a flavonoid derived from the root of the medicinal plant Scutellaria baicalensis Georgi (S. baicalensis) and is known for its various pharmacological properties. This study aimed to investigate the impact of baicalin (BAI) on the occurrence of kidney calcium oxalate crystal formation induced by ethylene glycol in male SD rats. MAIN METHODS: A rat model of renal stones was created and various concentrations of baicalin were used for intervention. Samples of urine, blood, and kidney tissue were taken from the rats, and they were euthanized for biochemical and histopathological examinations. KEY FINDINGS: Our results show that baicalin treatment improved the weight loss induced by ethylene glycol (EG) and ammonium chloride (AC) in rats. Baicalin also reduced the formation of calcium oxalate crystals and protected kidney function in rats with urolithiasis. Furthermore, it lowered the level of malondialdehyde (MDA) and elevated the activity of antioxidant enzymes compared to the stone control group. Additionally, baicalin notably alleviated renal inflammation in rats with urolithiasis. SIGNIFICANCE: The present study attributed clinical evidence first time that claiming the significant antiurolithic effect of baicalin and could be a cost-effective candidate for the prevention and treatment of urolithiasis.

Effect of magnesium oxide or citrate supplements on metabolic risk factors in kidney stone formers with idiopathic hyperoxaluria: a randomized clinical trial.

Magnesium is one of the recommended treatments for calcium stone formers (CSFs) with hyperoxaluria. In this study, we compared the effect of magnesium oxide (MgO) or magnesium citrate (MgCit) with placebo on 24-hour urine (24-U) metabolites and the calcium oxalate supersaturation index (CaOx SS). In a randomized, double-blind, placebo-controlled clinical trial, 90 CSFs with idiopathic hyperoxaluria were recruited from a tertiary stone prevention clinic. Patients were randomly assigned into three groups: 120 mg MgO, 120 mg MgCit or placebo (supplements were taken three times per day, with meals). Finally, 76 patients were included in the final analysis. Analyses of 24-U were performed at baseline and after eight weeks. Study outcomes included changes in 24-U oxalate, magnesium, citrate, and CaOx SS. Dietary factors were controlled by 24-hour food recalls. Repeated measure ANOVA was used to compare the results. After the intervention, both MgO and MgCit supplements decreased 24-U oxalate excretion (-8.13±16.45 in the MgO group and -16.99±18.02 in the MgCit group) and CaOx SS compared to the placebo, with the effects of MgCit reaching statistical significance (p=0.011 and p=0.010, respectively). An increasing trend was observed for 24-U magnesium and citrate excretion without significant differences among groups. Interestingly, MgCit exhibited a significantly greater inhibitory effect on 24-U oxalate in patients with normal urine magnesium levels (p=0.021). Clinically, both MgO and MgCit reduced 24-U oxalate and CaOx SS compared to placebo. However, MgCit demonstrated a greater effect, especially in patients with normal urine magnesium levels.

Gut and Urinary Microbiota in Cats with Kidney Stones.

Upper urinary tract urolithiasis is an emerging disease in cats, with 98% of kidney stones composed of calcium oxalate. In humans, disturbances in the intestinal and urinary microbiota are suspected to contribute to the formation of calcium oxalate stones. We hypothesized that similar mechanisms may be at play in cats. This study examines the intestinal and urinary microbiota of nine cats with kidney stones compared to nine healthy cats before, during, and after treatment with the antibiotic cefovecin, a cephalosporin. Initially, cats with kidney stones displayed a less diverse intestinal microbiota. Antibiotic treatment reduced microbiota diversity in both groups. The absence of specific intestinal bacteria could lead to a loss of the functions these bacteria perform, such as oxalate degradation, which may contribute to the formation of calcium oxalate stones. This study confirms the presence of a distinct urobiome in cats with kidney stones, characterized by greater richness and diversity compared to healthy cats. These findings highlight the potential of microbiota modulation as a strategy to prevent renal lithiasis in cats.

Protective Role of Rosmarinic Acid in Experimental Urolithiasis: Understanding Its Impact on Renal Parameters.

This study aimed to assess the ability of rosmarinic acid (RA) to prevent kidney stone formation in an ethylene glycol and ammonium chloride (EG/AC) model. There was an increase in diuresis in the normotensive (NTRs) and hypertensive rats (SHRs) treated with hydrochlorothiazide (HCTZ) and exposed to EG/AC, while RA restored urine volume in NTRs. The EG/AC groups exhibited lower urine pH and electrolyte imbalance; these parameters were not affected by any of the treatments. Both HCTZ+EG/AC and RA+EG/AC reduced calcium oxalate crystal formation in NTR and SHR urine. Kidney tissue analysis revealed alterations in oxidative stress and inflammation parameters in all EG/AC-receiving groups, with RA enhancing antioxidant defenses in SHRs. Additionally, crystals were found in the kidney histology of all EG/AC-exposed groups, with reduced Bowman's capsule areas in NTRs and SHRs. The NTR VEH+EG/AC group showed intense renal damage, while the others maintained their structures, where treatments with HCTZ and RA were fundamental for kidney protection in the NTRs. Docking analysis showed that RA exhibited good binding affinity with matrix metalloproteinase-9, phosphoethanolamine cytidylyltransferase, and human glycolate oxidase enzymes. The data disclosed herein underscore the importance of further research to understand the underlying mechanisms better and validate the potential of RA for clinical use.

MAGNESIUM SUPPLEMENTATION INCREASES URINE MAGNESIUM AND CITRATE IN STONE FORMERS WITH HYPOMAGNESURIA.

OBJECTIVES: To compare the effects of magnesium repletion by a foods-alone approach or by magnesium supplementation on urinary magnesium and citrate excretion in patients with urine magnesium <70 mg/day. METHODS: We reviewed medical records of patients in our stone prevention practice who were advised to start a magnesium supplement (Sup), 250-500 mg/d, or increase dietary magnesium consumption. We included adults with 24h UMg <70 mg, those who received magnesium recommendations (corroborated by the dietitian's clinical notes), and those with a follow-up 24h urine collection ≤18 months. Urine results were assessed by group. RESULTS: Groups [No Sup (n=74) and Sup (n=56)] were not different for age, gender, stone history, malabsorption, or other clinical indices. All patients raised UMg (53 to 69 and 47 to 87 mg/d for No Sup and Sup, respectively); however, the increase was significantly higher in the Sup group. Moreover, while 88% of Sup patients achieved UMg ≥70 mg/d, only 58% in the No Sup group did so. Within-group increases in urine citrate were significant only in the Sup group. CONCLUSION: Among patients with low UMg, both higher consumption from foods and magnesium supplementation significantly increased UMg. However, those who supplemented were significantly more likely to reach or exceed UMg 70 mg/d and achieved higher mean UMg. The change in urine citrate was significant only among those in the Sup group.

The urinary microbiota composition and functionality of calcium oxalate stone formers.

Background: Accumulated evidences indicate that dysbiosis of the urinary microbiota is associated with kidney stone formation. In the present study, we aimed to investigate the urinary microbiota composition and functionality of patients with calcium oxalate stones and compare it with those of healthy individuals. Method: We collected bladder urine samples from 68 adult patients with calcium oxalate stones and 54 age-matched healthy controls by transurethral catheterization. 16S rRNA gene and shotgun sequencing were utilized to characterize the urinary microbiota and functionality associated with calcium oxalate stones. Results: After further exclusion, a total of 100 subjects was finally included and analyzed. The diversity of the urinary microbiota in calcium oxalate stone patients was not significantly different from that of healthy controls. However, the urinary microbiota structure of calcium oxalate stone formers significantly differed from that of healthy controls (PERMANOVA, r = 0.026, P = 0.019). Differential representation of bacteria (e.g., Bifidobacterium) and several enriched functional pathways (e.g., threonine biosynthesis) were identified in the urine of calcium oxalate stone patients. Conclusion: Our results showed significantly different urinary microbiota structure and several enriched functional pathways in calcium oxalate stone patients, which provide new insight into the pathogenesis of calcium oxalate stones.

Morphology and composition of calcium oxalate monohydrate phytoliths in the bark of Betula ermanii (stone birch): Case study from Sakhalin Island.

The morphology of calcium oxalate monohydrate precipitates (COM, Ca(C2O4)·H2O, P21/c, whewellite) occurring as crystals or intergrowths, as well as distribution of crystal-bearing idioblasts, have been studied for the first time in the bark of stone birch Betula ermanii from Sakhalin Island sampled in an area affected by mud volcanism and an unaffected typical forest environment taken for reference. The study addresses several issues (i) number and size of phytoliths and their distribution in different cell types; (ii) density of calcification in specific cells; (iii) habits of single crystals, twins, and complex intergrowths, as well as frequency of different morphologies and their relations. The trends of time-dependent morphological changes in separately analyzed crystals and intergrowths record the evolution of COM morphology from nuclei to mature grains. Of special interest are the nucleation sites and features of organic and inorganic seeds and nuclei for COM phytoliths. The precipitation process and crystal habits are mainly controlled by supersaturation, and it is thus important to constrain the Ca distribution patterns in different bark tissues. The B. ermanii samples were analyzed by several methods: scanning electron microscopy (SEM) for the distribution patterns and micromorphology of COM precipitates and bulk Ca content in bark; electron probe microanalysis (EPMA) for the mineral chemistry of COM precipitates; inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) for trace elements in bulk bark and wood. RESEARCH HIGHLIGHTS: The distribution and morphology of whewellite precipitates in the analyzed B. ermanii bark samples indicate that the aqueous solution was most strongly supersaturated with respect to the Ca(C2O4)·H2O solid phase at the parenchyma-sclerenchyma boundary, where most of the COM spherulites are localized and often coexist with large single crystals and contact COM twins.

Current Dietary and Medical Prevention of Renal Calcium Oxalate Stones.

Kidney stones refer to abnormal crystal formation that occurs in the kidney. Among a variety of components of kidney stones, calcium oxalate (CaOx) is the most common type. Despite many efforts to investigate the pathogenesis of CaOx stones, the pathogenesis remains an issue of debate. With high occurrence and recurrence, individuals with stone formation are prone to frequently consult a doctor and to be hospitalized, and the treatment of kidney stones poses a heavy burden on the patients. Concerns should be focused not only on treatment but also on prevention. Herein, we reviewed the studies on prevention methods of CaOx stones through diet, lifestyle, and medication extending until the current time frame. As hyperoxaluria is the most common metabolic disorder among CaOx stone formations, we also included several studies on the treatment and prevention of hyperoxaluria. Our objective was to outline the effective methods to prevent renal CaOx stone formation.

The optimal Holmium laser settings for disintegration of cystine and calcium oxalate monohydrate stones: In vitro study.

Objective: Disintegrating cystine and calcium oxalate monohydrate stones present a formidable challenge owing to their hardness and distinct composition. This study aimed to establish optimal laser settings for these hard stones lithotripsy. Patients and Methods: Cystine and calcium oxalate monohydrate stones were extracted from two patients. Two experiments were conducted in vitro by utilizing a 272 µm laser fiber with variable settings to disintegrate the cystine and calcium oxalate monohydrate stones. In the first experiment, energy was adjustable while frequency was constant, whereas the second experiment involved constant energy with adjustable frequency on each type of stone and each experiment was repeated three times to ensure robustness and reliability. Results: Our findings indicated that for cystine stones, use of higher total power with high energy and low frequency proved to be effective. Conversely, for calcium oxalate monohydrate stones, settings involving higher total power with low energy and high frequency demonstrated superior efficacy and safety. Conclusion: Holmium (Ho: YAG) laser settings with higher total power, high energy, and low frequency effectively disintegrate cystine stones despite increased heat, which was measured by a thermometer with a thermocouple. For calcium oxalate monohydrate stones, higher total power, high frequency, and low energy settings are recommended and safe.

Proton pump inhibitors use is associated with a higher prevalence of kidney stones: NHANES 2007-2018.

BACKGROUND: Proton pump inhibitors (PPIs) are widely used throughout the world as an effective gastrointestinal drug. Nevertheless, according to the existing literature, PPIs can reduce the excretion of magnesium, calcium and other components in urine, which may promote the formation of kidney stones. We used the National Health and Nutrition Examination Survey (NHANES) database to further investigate the association between the use of PPIs and the prevalence of kidney stones. METHODS: We performed a cross-sectional analysis using data from 2007 to 2018 NHANES. PPIs use information of 29,910 participants was obtained by using prescription medications in the preceding month, and kidney stones were presented by a standard questionnaire. Multiple regression analysis and stratified analysis were used to estimate the association between PPIs use and kidney stones after an adjustment for potential confounders. RESULTS: The multiple logistic regression indicated that the PPIs exposure group (P1) had a significantly higher risk of nephrolithiasis than the PPIs non-exposure group (P0) in Model 3 (OR 1.24, 95% CI 1.10-1.39, P < 0.001). The stratified analyses indicated there were significant statistical differences between PPIs use and kidney stones among females (OR 1.36, 95% CI 1.15-1.62, P < 0.001), non-Hispanic whites (OR 1.27, 95% CI 1.09-1.48, P = 0.002), individuals with an education level than 11th grade (OR 1.41, 95% CI 1.13-1.76, P = 0.002) and individuals with an annual family income of $0 to $19,999 (OR 1.32, 95% CI 1.06-1.65, P = 0.014) and $20,000 to $44,999 (OR 1.25, 95% CI 1.02-1.54, P = 0.033) in Model 3. CONCLUSIONS: Our study revealed that PPIs use is associated with a higher prevalence of kidney stones for the US population, primarily among women, non-Hispanic whites, individuals with low education levels and individuals with low household income levels. Further studies are required to confirm our findings.