Label-free detection of kidney stones urine combined with SERS and multivariate statistical algorithm.

Kidney stones are a common urological disease with an increasing incidence worldwide. Traditional diagnostic methods for kidney stones are relatively complex and time-consuming, thus necessitating the development of a quicker and simpler diagnostic approach. This study investigates the clinical screening of kidney stones using Surface-Enhanced Raman Scattering (SERS) technology combined with multivariate statistical algorithms, comparing the classification performance of three algorithms (PCA-LDA, PCA-LR, PCA-SVM). Urine samples from 32 kidney stone patients, 30 patients with other urinary stones, and 36 healthy individuals were analyzed. SERS spectra data were collected in the range of 450-1800 cm-1 and analyzed. The results showed that the PCA-SVM algorithm had the highest classification accuracy, with 92.9 % for distinguishing kidney stone patients from healthy individuals and 92 % for distinguishing kidney stone patients from those with other urinary stones. In comparison, the classification accuracy of PCA-LR and PCA-LDA was slightly lower. The findings indicate that SERS combined with PCA-SVM demonstrates excellent performance in the clinical screening of kidney stones and has potential for practical clinical application. Future research can further optimize SERS technology and algorithms to enhance their stability and accuracy, and expand the sample size to verify their applicability across different populations. Overall, this study provides a new method for the rapid diagnosis of kidney stones, which is expected to play an important role in clinical diagnostics.

Retroperitoneal vs transperitoneal laparoscopic pyelolithotomy; a single surgeon's experience.

OBJECTIVE: To compare the outcomes of transperitoneal and retroperitoneal laparoscopic pyelolithotomy procedures. METHODS: A total of 104 consecutive laparoscopic pyelolithotomy surgeries performed by a single surgeon on patients with staghorn or renal pelvic calculi larger than 20 mm were evaluated. Intraoperative and postoperative clinical parameters from two groups, transperitoneal (TLPL) (N = 55) and retroperitoneal (RLPL) (N = 49), were compared. The surgeon performed TLPL for the first five years and then switched to the RLPL approach for the next five years. RESULTS: There were no significant differences in general demographic variables and stone size (26.55 vs. 24.73 mm, P = 0.8). Operation time and change in serum creatinine levels did not significantly differ between the two approaches. However, patients who underwent TLPL had longer hospital stays than RLPL (3.23 ± 1.21 vs. 2.36 ± 1.10 days, P = 0.0001). Additionally, TLPL was associated with a greater drop in hemoglobin levels (1.53 ± 1.04 vs. 1.17 ± 0.68, P = 0.04), higher rates of postoperative fever (12.7% vs. 0.0%, P = 0.01). CONCLUSIONS: The retroperitoneal approach in laparoscopic pyelolithotomy for large renal pelvic stones resulted in fewer postoperative fevers, reduced hemoglobin drops, and shorter hospital stays than the transperitoneal approach. However, the stone-free rates were similar for both groups.

The Role of the Gut Microbiome in Kidney Stone Disease.

Microbiome dysbiosis is closely related to the etiology of kidney stone disease (KSD) and influences a multitude of pathways. Due to our knowledge gaps on this topic, it is still unclear if microbiome interventions can be translated to demonstrate clinical efficacy. Current evidence suggests that the enhancement of butyrate-producing pathways should be the next step for KSD research. While we are not yet at a point where we can make clinical recommendations for KSD, there are many simple dietary or supplement-based approaches that could be applied in the future for prophylaxis or treatment of KSD.

Proteome-wide mendelian randomization identifies therapeutic targets for nephrolithiasis.

Kidney Stone Disease (KSD) constitutes a multifaceted disorder, emerging from a confluence of environmental and genetic determinants, and is characterized by a high frequency of occurrence and recurrence. Our objective is to elucidate potential causative proteins and identify prospective pharmacological targets within the context of KSD. This investigation harnessed the unparalleled breadth of plasma protein and KSD pooled genome-wide association study (GWAS) data, sourced from the United Kingdom Biobank Pharma Proteomics Project (UKBPPP) and the FinnGen database version R10. Through Mendelian randomization analysis, proteins exhibiting a causal influence on KSD were pinpointed. Subsequent co-localization analyses affirmed the stability of these findings, while enrichment analyses evaluated their potential for pharmacological intervention. Culminating the study, a phenome-wide association study (PheWAS) was executed, encompassing all phenotypes (2408 phenotypes) catalogued in the FinnGen database version R10. Our MR analysis identified a significant association between elevated plasma levels of proteins FKBPL, ITIH3, and SERPINC1 and increased risk of KSD based on genetic predictors. Conversely, proteins CACYBP, DAG1, ITIH1, and SEMA6C showed a protective effect against KSD, documented with statistical significance (PFDR<0.05). Co-localization analysis confirmed these seven proteins share genetic variants with KSD, signaling a shared genetic basis (PPH3 + PPH4 > 0.8). Enrichment analysis revealed key pathways including hyaluronan metabolism, collagen-rich extracellular matrix, and serine-type endopeptidase inhibition. Additionally, our PheWAS connected the associated proteins with 356 distinct diseases (PFDR<0.05), highlighting intricate disease interrelations. In conclusion, our research elucidated a causal nexus between seven plasma proteins and KSD, enriching our grasp of prospective therapeutic targets.

Biology of calcium homeostasis regulation in intestine and kidney.

Calcium (Ca2+) is an essential divalent cation involved in many bodily functions including bone composition, cell growth and division, blood clotting, and muscle contraction. The bone, intestine, and kidneys are important to the maintenance of Ca2+ homeostasis. Ninety-nine percent of body Ca2+ is stored in the skeleton as hydroxyapatite. The small, and to a lesser extent the large intestine absorbs Ca2+ from the diet. Once in the circulation, Ca2+ is filtered by the glomerulus and the majority, >95%, is reabsorbed along the nephron. The remainder is excreted in the urine. Two general (re)absorptive pathways contribute to the vectorial transport of Ca2+ across renal and intestinal epithelia: 1) a paracellular pathway, which is reliant on claudins in the tight junction of epithelium and the electrochemical gradient and 2) a transcellular pathway, which requires different influx, intracellular buffering/shuttling and basolateral efflux mechanisms, to actively transport Ca2+ across the epithelial cell. Blood Ca2+ levels are maintained by hormones including parathyroid hormone, 1,25-dihydroxyvitamin D3, fibroblast growth factor 23 and through effects of Ca2+-sensing receptor (CaSR) signaling. Disruption of Ca2+ homeostasis can result in altered blood Ca2+ levels and/or hypercalciuria, the latter is a phenomenon closely linked to the formation of kidney stones. Genetic alterations affecting renal Ca2+ handling can cause hypercalciuria, an area of expanding investigation. This review explores the molecular mechanisms governing Ca2+ homeostasis by the intestine and kidneys and discusses clinical aspects of genetic disorders associated with Ca2+-based kidney stone disease.

Corrigendum: Association between weight-adjusted waist index and kidney stones: a propensity score matching study.

[This corrects the article DOI: 10.3389/fendo.2024.1266761.].

Application of warning biopsies in percutaneous nephrolithotomy.

Background: At present, few articles on percutaneous nephrolithotomy (PCNL) for renal calculi and renal pelvic tumors detected by intraoperative biopsy exist, which has provided limited guidance for clinical practice. In this article, we aimed to further study the relationship between renal calculi and renal pelvic tumors. Methods: We retrospectively analyzed the medical records of patients with abnormal mucosal biopsy results who underwent PCNL for kidney stones in the Urology Department of Peking University People's Hospital from January 2011 to November 2021. Results: In total, 2,801 patients underwent PCNL for kidney stones, of whom 69 underwent intraoperative mucosal biopsy. Biopsy results indicated that 8 cases were malignant (11.60%), and 61 cases were benign (88.40%). All malignant cases were renal pelvic carcinoma. Seven were urothelial carcinoma, and one of these was urothelial carcinoma with squamous differentiation. Only one was squamous cell carcinoma. The preoperative information of patients with a malignant mucosa biopsy was analyzed. To provide clinical guidance, an early warning biopsy system was established based on the abnormal mucosa found during the operation. We found that PCNL should be considered if the following risk factors are associated with stones: advanced age, long history of kidney stones, severe hydronephrosis, urinary tract infection, multiple or staghorn stones. Conclusions: Early warning information should be established for patients with kidney stones based on preoperative clinical characteristics and intraoperative mucous membrane observations. An early warning biopsy should be performed for patients with possible tumors to detect tumors in a timely manner and provide early treatment to improve patient prognosis.

Alcohol Intake and Prevalent Kidney Stone: The National Health and Nutrition Examination Survey 2007-2018.

The association of alcohol intake with kidney stone disease (KSD) is not clear based on current clinical evidence. We examined the National Health and Nutrition Examination Survey (NHANES) 2007-2018 and used logistic regression analyses to determine the independent association between alcohol intake and prevalent KSD. In total, 29,684 participants were eligible for the final analysis, including 2840 prevalent stone formers (SFs). The mean alcohol intake was 37.0 ± 2.4 g/day among SFs compared to 42.7 ± 0.9 among non-SFs (p = 0.04). Beer [odds ratio (OR) = 0.76, 95% CI: 0.61-0.94, p = 0.01] and wine (OR = 0.75, 95% CI: 0.59-0.96, p = 0.03) intakes were strongly associated with lower odds of prevalent KSD, while liquor intake had no association. Furthermore, the effects of beer and wine intakes on stone formation were dose-dependent. The OR for comparing participants drinking 1-14 g/day of beer to non-drinkers was 1.41 (95%CI: 0.97-2.05, p = 0.07), that of >14-≤28 g/day of beer to non-drinkers was 0.65 (95% CI: 0.42-1.00, p = 0.05), that of >28-≤56 g/day of beer to non-drinkers was 0.60 (95% CI: 0.39-0.93, p = 0.02), and that of >56 g/day of beer to non-drinkers was 0.34 (95% CI: 0.20-0.57, p < 0.001). Interestingly, the effect of wine intake was only significant among participants drinking moderate amounts (>14-28 g/day), with an OR of 0.54 (95% CI: 0.36-0.81, p = 0.003) compared to non-drinkers, but this effect was lost when comparing low-level (1-14 g/day) and heavy (>28 g/day) wine drinkers to non-drinkers. These effects were consistent in spline models. This study suggests that both moderate to heavy beer intake and moderate wine intake are associated with a reduced risk of KSD. Future prospective studies are needed to clarify the causal relationship.

Influence of Dietary Heritage in a Restricted Geographic Area and Role of Food Additives on Risk of Recurrent Kidney Stone.

Dietary factors may be implicated in the formation of kidney stones and should be closely monitored. To achieve this aim, patients are routinely assessed by means of generic dietary recall, a tool widely used by authors in a range of extensive patient populations to record food intake; the findings obtained, however, may be skewed due to dietary variations and underestimation of the effect of food additives. Fifty Frequent Kidney Stone Formers (FKSFs, mean age: 54.3 ± 13.9 years) with normal kidney function, absence of comorbidities, and reliable compliance were selected from a total of 68 patients' resident in Sardinia, an Italian island where genetic admixtures have been relatively rare for generations. The study, conducted from 1 January 2020 to 31 December 2023, was aimed at assessing nutritional values based on the meticulous recording of food quantities, quality, and potential modifications related to food preparation. Patients were selected during an initial clinical check-up and all efforts made to ensure they were capable of reliably recording all food and drinks consumed. A seven-day food diary was provided in which food and drink intake and their impact on 24 h urine output was recorded. The following parameters were measured in both foods and urine output: citrates, oxalates, calcium, phosphorous, uric acid, proteins and nitrogen compounds, magnesium, sulfates, potassium, carbohydrates, free fatty acids. Study outcomes established the presence of hypocitraturia, hyperoxaluria, hypercalciuria, and moderately high levels of nitrogen compounds. Univariate analysis followed by multivariate analysis for further confirmation were performed and the following observations made. Citrate intake correlated with citraturia but did not promote oxaluria; calcium intake promoted onset of sulfaturia, azoturia, and ammoniuria, whilst magnesium correlated with magnesiuria but not with oxaluria, calciuria, phosphaturia, and azoturia; sulfate intake elicited onset of azoturia but not kaliuresis; potassium intake promoted oxaluria and protein intake resulted in onset of ammoniuria and azoturia. (A) The chemical composition of urine based on dietary intake is hard to predict without taking into account the presence of dietary and urinary interferents; (B) the geographic isolation of patients studied underlines the importance of epigenetics in maintaining a traditional dietary heritage. (C) Moreover, the widespread use of food additives should consistently be taken into account to ensure a correct diagnosis of FKSF and set up a valid treatment plan.

Defining physicochemical properties of urinary proteins that determine their inhibitory activities against calcium oxalate kidney stone formation.

We have recently reported a set of urinary proteins that inhibited calcium oxalate (CaOx) stone development. However, physicochemical properties that determine their inhibitory activities remained unknown. Herein, human urinary proteins were chromatographically fractionated into 15 fractions and subjected to various CaOx crystal assays and identification by nanoLC-ESI-Qq-TOF MS/MS. Their physicochemical properties and crystal inhibitory activities were subjected to Pearson correlation analysis. The data showed that almost all urinary protein fractions had crystal inhibitory activities. Up to 128 proteins were identified from each fraction. Crystallization inhibitory activity correlated with percentages of Ca2+-binding proteins, stable proteins, polar amino acids, alpha helix, beta turn, and random coil, but inversely correlated with number of Ox2--binding motifs/protein and percentage of unstable proteins. Crystal aggregation inhibitory activity correlated with percentage of stable proteins but inversely correlated with percentage of unstable proteins. Crystal adhesion inhibitory activity correlated with percentage of stable proteins and GRAVY, but inversely correlated with pI, instability index and percentages of unstable proteins and positively charged amino acids. However, there was no correlation between crystal growth inhibitory activity and any physicochemical properties. In summary, some physicochemical properties of urinary proteins can determine and may be able to predict their CaOx stone inhibitory activities.