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Patients with kidney stone disease are at higher risk for bone disease. Hypocitraturia is common in patients with kidney stone disease and a key risk factor for stone recurrence. In this retrospective cohort study, we sought to determine whether hypocitraturia is also a risk factor for incident bone disease in patients with kidney stone disease. We used nationwide data from the Veterans Health Administration and identified 9025 patients with kidney stone disease who had a 24‐hour urine citrate measurement between 2007 and 2015. We examined clinical characteristics of patients by level of 24‐hour urine citrate excretion (<200, 200–400, and >400 mg/d) and the time to osteoporosis or fracture according to 24‐hour urine citrate excretion level. Almost one in five veterans with kidney stone disease and a 24‐hour urine citrate measurement had severe hypocitraturia, defined as <200 mg/d. Patients with severe hypocitraturia were at risk for osteoporosis or fracture (hazard ratio [HR] = 1.23; confidence interval [CI] 1.03–1.48), but after adjustment for demographic factors, comorbid conditions, and laboratory abnormalities associated with hypocitraturia, the association was no longer statistically significant (HR = 1.18; CI 0.98–1.43). Our results in a predominantly male cohort suggest a modest association between hypocitraturia and osteoporosis or fracture; there are likely to be other explanations for the potent association between kidney stone disease and diminished bone health. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

Context: Primary hyperparathyroidism (PHPT) is associated with an increased risk of kidney stones. Few studies account for PHPT severity or stone risk when comparing stone events after parathyroidectomy vs nonoperative management. Objective: Compare the incidence of kidney stone events in PHPT patients treated with parathyroidectomy vs nonoperative management. Design: Longitudinal cohort study with propensity score inverse probability weighting and multivariable Cox proportional hazards regression. Setting: Veterans Health Administration integrated health care system. Patients: A total of 44 978 patients with > 2 years follow-up after PHPT diagnosis (2000-2018); 5244 patients (11.7%) were treated with parathyroidectomy. Main outcomes measure: Clinically significant kidney stone event. Results: The cohort had a mean age of 66.0 years, was 87.8% male, and 66.4% White. Patients treated with parathyroidectomy had higher mean serum calcium (11.2 vs 10.8mg/dL) and were more likely to have a history of kidney stone events. Among patients with baseline history of kidney stones, the unadjusted incidence of = 1 kidney stone event was 30.5% in patients managed with parathyroidectomy (mean follow-up, 5.6 years) compared with 18.0% in those managed nonoperatively (mean follow-up, 5.0 years). Patients treated with parathyroidectomy had a higher adjusted hazard of recurrent kidney stone events (hazard ratio [HR], 1.98; 95% CI, 1.56-2.51); however, this association declined over time (parathyroidectomy × time: HR, 0.80; 95% CI, 0.73-0.87). Conclusion: In this predominantly male cohort with PHPT, patients treated with parathyroidectomy continued to be at higher risk of kidney stone events in the immediate years after treatment than patients managed nonoperatively, although the adjusted risk of stone events declined with time, suggesting a benefit to surgical treatment. [ABSTRACT FROM AUTHOR]

Introduction and Objective: Ureteroscopy (URS) and percutaneous nephrolithotomy (PCNL) are standard treatments for intermediate-size (15–20 mm) kidney stones but differ in their postoperative recovery, stone-free rates, and complication risks. We aimed to evaluate what affects patient treatment preferences. Methods: Patients with urinary stone disease completed a choice-based conjoint analysis exercise assessing four treatment attributes associated with URS and PCNL. A sensitivity analysis using a market simulator was performed, and the relative importance of each attribute was calculated. Differences in treatment preferences by demographic subgroup were assessed. Results: A total of 58 patients completed the conjoint analysis exercise. Stone-free rate was the most important treatment attribute, while the length of hospital stay and cosmesis were less important. Overall, sensitivity analysis based on market simulation scenarios predicted an almost equal preference for URS (52.4%) compared with PCNL (47.6%) for treatment of an intermediate-size stone. Older patients (>65 years old) expressed their stronger preferences for lower infection rates and shorter hospital stays, and were more likely to prefer URS (67.2%, 95% confidence interval [CI]: 52% to 82.5%) compared with younger patients (20–34 years old) (20.3%, 95% CI: 0% to 41.5%) who preferred higher procedure success rates and fewer repeat procedures. Conclusion: Conjoint analysis predicts nearly equal patient preference for URS or PCNL for the treatment of intermediate-size kidney stones. Older patients prefer the lower urinary tract infection risk and shorter hospital stay associated with URS, while younger patients prefer higher stone-free rates associated with PCNL. These results can help guide urologists in counseling patients and improve the shared decision-making process. [ABSTRACT FROM AUTHOR]

Objective: The American Urological Association guidelines recommend 24-hour urine testing in patients with urinary stone disease to decrease the risk of stone recurrence; however, national practice patterns for 24-hour urine testing are not well characterized. Our objective is to determine the prevalence of 24-hour urine testing in patients with urinary stone disease in the Veterans Health Administration and examine patient-specific and facility-level factors associated with 24-hour urine testing. Identifying variations in clinical practice can inform future quality improvement efforts in the management of urinary stone disease in integrated healthcare systems. Materials and methods: We accessed national Veterans Health Administration data through the Corporate Data Warehouse (CDW), hosted by the Veterans Affairs Informatics and Computing Infrastructure (VINCI), to identify patients with urinary stone disease. We defined stone formers as Veterans with one inpatient ICD-9 code for kidney or ureteral stones, two or more outpatient ICD-9 codes for kidney or ureteral stones, or one or more CPT codes for kidney or ureteral stone procedures from 2007 through 2013. We defined a 24-hour urine test as a 24-hour collection for calcium, oxalate, citrate or sulfate. We used multivariable regression to assess demographic, geographic, and selected clinical factors associated with 24-hour urine testing. Results: We identified 130,489 Veterans with urinary stone disease; 19,288 (14.8%) underwent 24-hour urine testing. Patients who completed 24-hour urine testing were younger, had fewer comorbidities, and were more likely to be White. Utilization of 24-hour urine testing varied widely by geography and facility, the latter ranging from 1 to 40%. Conclusions: Fewer than one in six patients with urinary stone disease complete 24-hour urine testing in the Veterans Health Administration. In addition, utilization of 24-hour urine testing varies widely by facility identifying a target area for improvement in the care of patients with urinary stone disease. Future efforts to increase utilization of 24-hour urine testing and improve clinician awareness of targeted approaches to stone prevention may be warranted to reduce the morbidity and cost of urinary stone disease. [ABSTRACT FROM AUTHOR]

Purpose: Surgery for upper tract urinary stone disease is often reserved for symptomatic patients and those whose stone does not spontaneously pass after a trial of passage. Our objective was to determine whether payer type or race/ethnicity is associated with the timeliness of kidney stone surgery. Materials and Methods: A population-based cohort study was conducted using the California Office of Statewide Health Planning and Development dataset from 2010 to 2012. We identified patients who were discharged from an emergency department (ED) with a stone diagnosis and who subsequently underwent a stone surgery. Primary outcome was time from ED discharge to urinary stone surgery in days. Secondary outcomes included potential harms resulting from delayed stone surgery. Results: Over the study period, 15,193 patients met the inclusion criteria. Median time from ED discharge to stone surgery was 28 days. On multivariable analysis patients with Medicaid, Medicare, and self-pay coverage experienced adjusted mean increases of 46%, 42%, and 60% in time to surgery, respectively, when compared with those with private insurance. In addition, patients of Black and Hispanic race/ethnicity, respectively, experienced adjusted mean increases of 36% and 20% in time to surgery relative to their White counterparts. Before a stone surgery, underinsured patients were more likely to revisit an ED three or more times, undergo two or more CT imaging studies, and receive upper urinary tract decompression. Conclusions: Underinsured and minority patients are more likely to experience a longer time to stone surgery after presenting to an ED and experience potential harm from this delay. [ABSTRACT FROM AUTHOR]

Objectives: We sought to validate the use of crowdsourced surgical video assessment in the evaluation of urology residents performing flexible ureteroscopic laser lithotripsy. Methods: We collected video feeds from 30 intrarenal ureteroscopic laser lithotripsy cases where residents, postgraduate year (PGY) two through six, handled the ureteroscope. The video feeds were annotated to represent overall performance and to contain parts of the procedure being scored. Videos were submitted to a commercially available surgical video evaluation platform (Crowd-Sourced Assessment of Technical Skills). We used a validated ureteroscopic laser lithotripsy global assessment tool that was modified to include only those domains that could be evaluated on the captured video. Videos were evaluated by crowd workers recruited using Amazon's Mechanical Turk platform as well as five endourology-trained experts. Mean scores were calculated and intraclass correlation coefficients (ICCs) were computed for the expert domain and total scores. ICCs were estimated using a linear mixed-effects model. Spearman rank correlation coefficients were calculated as a measure of the strength of the relationships between the crowd mean and expert average scores. Results: A total of 30 videos were reviewed 2488 times by 487 crowd workers and five expert endourologists. ICCs between expert raters were all below accepted levels of correlation (0.30), with the overall score having an ICC of <0.001. For individual domains, the crowd scores did not correlate with expert scores, except for the stone retrieval domain (0.60 p = 0.015). In addition, crowdsourced scores had a negative correlation with the PGY level (0.44, p = 0.019). Conclusions: There is poor agreement between experts and poor correlation between expert and crowd scores when evaluating video feeds of ureteroscopic laser lithotripsy. The use of an intraoperative video of ureteroscopy with laser lithotripsy for assessment of resident trainee skills does not appear reliable. This is further supported by the lack of correlation between crowd scores and advancing PGY level. [ABSTRACT FROM AUTHOR]

We have developed the Peralta Stone Extraction System to increase the safety of ureteral stone extraction. The device combines a nitinol stone basket and low-pressure balloon into a single device. After visualization, the stone is captured in the tipless nitinol basket and enveloped by a low-pressure balloon. We tested the performance of device prototypes in a porcine model using stone mimics with diameters ranging from 4.2 to 6.2 mm. Stones extracted with the device required less force when compared with stones in a standard ureteral stone basket. The force reduction was most pronounced for stones greater than 4.2mm in diameter, and when traversing a ureteral stenosis model. In conclusion, a combination stone basket and balloon device may provide a new and safer way to extract ureteral stones. [ABSTRACT FROM AUTHOR]

Objectives: The American Southeast has been labeled the 'Stone Belt' due to its relatively high burden of urinary stone disease, presumed to be related to its higher temperatures. However, other regions with high temperatures (e.g., the Southwest) do not have the same disease prevalence as the southeast. We seek to explore the association of stone disease to other climate-associated factors beyond temperature, including precipitation and temperature variation. Methods: We identified all patients who underwent a surgical procedure for urinary stone disease from the California Office of Statewide Health Planning and Development (OSHPD) databases (2010-2012). Climate data obtained from the National Oceanic and Atmospheric Administration (NOAA) were compared to population adjusted county operative stone burden, controlling for patient and county demographic data as potential confounders. Results: A total of 63,994 unique patients underwent stone procedures in California between 2010 and 2012. Multivariate modeling revealed that higher precipitation (0.019 average increase in surgeries per 1000 persons per inch, p < 0.01) and higher mean temperature (0.029 average increase in surgeries per 1000 persons per degree, p < 0.01) were both independently associated with an increased operative stone disease burden. Controlling for county-level patient factors did not change these observed effects. Conclusions: In the state of California, higher precipitation and higher mean temperature are associated with increased rates of stone surgery. Our results appear to agree with the larger trends seen throughout the United States where the areas of highest stone prevalence have warm wet climates and not warm arid climates. [ABSTRACT FROM AUTHOR]

Study Type – Diagnostic (exploratory cohort) Level of Evidence 2b OBJECTIVE To prospectively determine the accuracy of 14-, 18- and 20-G core needle biopsies to render the appropriate histological diagnosis of solid, enhancing renal masses, using a controlled, ex-vivo biopsy technique. PATIENTS AND METHODS From March 2007 to September 2007, 31 patients undergoing partial or radical nephrectomy were randomly selected for biopsy. After extirpative surgery, three ex-vivo biopsies were taken from each lesion with 14-, 18- and 20-G biopsy needles. One experienced genitourinary pathologist, unaware of patient identifiers and final pathology results, determined the biopsy histology and tumour grade, based on standard haematoxylin and eosin (H&E) techniques and immunohistochemistry. RESULTS The final pathological evaluation classified 21 masses (68%) as clear cell renal cell carcinoma (RCC), three (10%) as papillary RCC, three (10%) as chromophobe RCC, three (10%) as oncocytoma and one (3%) as a benign lymphoid infiltrate. The biopsy histology correlated with the final pathology in 29/31 cases (94%) with the 14-G, 30/31 cases (97%) with the 18-G and 25/31 cases (81%) with the 20-G needles. In two cases chromophobe RCC was misdiagnosed with oncocytoma, and vice versa. CONCLUSION In this study a minimum of an 18-G biopsy needle was the most accurate in determining the histological diagnosis. Clear cell and papillary RCCs were accurately diagnosed on biopsy using an 18-G, whereas oncocytoma and chromophobe RCC were difficult to differentiate using standard H&E techniques and immunohistochemistry. [ABSTRACT FROM AUTHOR]

The article reflects two prevalent diseases including diabetes and kidney stone disease. It mentions that the National Health and Nutrition Examination Survey by National Center for Health Statistics, which is a part of the Centers for Disease Control and Prevention (NHANES 2007-2010) found prevalence of kidney stones to be an 8.8 percent. It informs that studies in the U.S. population have shown increase in type 2 diabetes mellitus (T2DM), obesity, and the metabolic syndrome.

Abstract: Background: External shock wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PNL) have been the standard of care for the treatment of intrarenal calculi. Objective: We sought to determine the safety and efficacy of flexible ureteroscopy and holmium laser lithotripsy for the treatment of multiple intrarenal calculi and further stratify the efficacy by stone burden less than and greater than 20mm. Design, setting, and participants: Patients with multiple unilateral renal calculi treated between 2000 and 2006 at a single tertiary academic center were retrospectively evaluated. Intervention: All patients underwent retrograde flexible ureteroscopy and holmium laser lithotripsy. Measurements: Stone-free status was determined by ureteroscopy 15 d after the last procedure and was defined as the absence of stones in the kidney or residual fragments <1mm. A renal ultrasound was performed 30 d after the last treatment to confirm the absence of stones and hydronephrosis. Results and Limitations: Fifty-one patients were identified for a total of 161 intrarenal calculi with a mean stone size per patient of 6.6±3mm (range: 2–15). The mean number of stones per patient was 3.1±1 (range: 2–6). The mean number of primary procedures was 1.4±0.6 (range: 1–3). The overall stone-free rates after one and two procedures were 64.7% and 92.2%, respectively. The stone-free rates for patients with a stone burden greater than and less than 20mm were 85.1% and 100%, respectively. The overall complication rate was 13.6%; 97.6% of cases were performed as outpatient procedures. There are some limitations to this study, however: This is a retrospective review from a single institution, and our results are based on a relatively small sample size. Conclusions: For select patients with multiple intrarenal calculi, flexible ureteroscopy with holmium laser lithotripsy may represent an alternative therapy to ESWL or PNL, with acceptable efficacy and low morbidity. [Copyright &y& Elsevier]

Abstract: Background: The prevalence of kidney stone disease is rising along with increasing rates of obesity, type 2 diabetes mellitus (T2DM), and metabolic syndrome. Objective: To investigate the associations among the presence and severity of T2DM, glycemic control, and insulin resistance with kidney stone disease. Design, setting, and participants: We performed a cross-sectional analysis of all adult participants in the 2007–2010 National Health and Nutrition Examination Survey (NHANES). A history of kidney stone disease was obtained by self-report. T2DM was defined by self-reported history, T2DM-related medication usage, and reported diabetic comorbidity. Insulin resistance was estimated using fasting plasma insulin (FPI) levels and the homeostasis model assessment of insulin resistance (HOMA-IR) definition. We classified glycemic control using glycosylated hemoglobin A1c (HbA1c) and fasting plasma-glucose levels (FPG). Outcome measurements and statistical analysis: Odds ratios (OR) for having kidney stone disease were calculated for each individual measure of T2DM severity. Logistic regression models were fitted adjusting for age, sex, race/ethnicity, smoking history, and the Quételet index (body mass index), as well as laboratory values and components of metabolic syndrome. Results and limitations: Correlates of kidney stone disease included a self-reported history of T2DM (OR: 2.44; 95% confidence interval [CI], 1.84–3.25) and history of insulin use (OR: 3.31; 95% CI, 2.02–5.45). Persons with FPG levels 100–126mg/dl and >126mg/dl had increased odds of having kidney stone disease (OR 1.28; 95% CI, 0.95–1.72; and OR 2.29; 95% CI, 1.68–3.12, respectively). Corresponding results for persons with HbA1c 5.7–6.4% and ≥6.5% were OR 1.68 (95% CI, 1.17–2.42) and OR 2.82 (95% CI, 1.98–4.02), respectively. When adjusting for patient factors, a history of T2DM, the use of insulin, FPI, and HbA1c remained significantly associated with kidney stone disease. The cross-sectional design limits causal inference. Conclusions: Among persons with T2DM, more-severe disease is associated with a heightened risk of kidney stones. [Copyright &y& Elsevier]