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Several studies have reported associations between vascular calcifications and urinary stone disease (USD). However, results have been inconsistent and the majority of studies did not report on race/ethnicity. We examined the association between vascular calcifications and USD in a large, racially/ethnically diverse patient population. We identified 672 USD cases and 672 controls (i.e., patients without a history of USD) from patients who underwent non-contrast CT imaging at Montefiore Medical Center in Bronx, New York between 2004 and 2013. Controls were matched to cases on age, sex and race/ethnicity. The non-contrast CT imaging was used to measure abdominal aortic calcification (AAC) and calculate the AAC severity score. Logistic regression models were used to examine associations of AAC presence and severity score with risks of USD and stone types. Cases and controls had similar AAC prevalence (45.2% vs. 44.8%, p = 0.87), and AAC severity score (median 10 vs. 9.3, p = 0.47). The presence of AAC (OR = 0.98, 95% CI 0.78–1.23; p = 0.86) or AAC severity score were not associated with risk of USD: ORs of 0.96, 0.87, 1.07 and 1.03 for increasing AAC quartiles (p-trend = 0.54). There were also no associations in the stratified analyses by race/ethnicity or by sex. However, when USD patients were stratified by stone type, brushite/apatite stone formers had an inverse association with the lowest quartile of AAC severity score (OR = 0.35, 95% CI 0.11–0.84, p = 0.04) in comparison to patients without AAC. Overall, we found no association between vascular calcifications and risk of urinary stone disease in this large, hospital-based, case–control study. [ABSTRACT FROM AUTHOR]

Antibiotics can alter the gut microbiome (GMB), which may be associated with stone disease. We sought to determine the effect that antibiotics have on the GMB, urine ion excretion and stone formation in genetic hypercalciuric stone-forming (GHS) rats. 116th generation GHS rats were fed a fixed amount of a normal calcium (1.2%) and phosphate (0.65%) diet, and divided into three groups (n = 10): control (CTL) diet, or supplemented with ciprofloxacin (Cipro, 5 mg/day) or Bactrim (250 mg/day). Urine and fecal pellets were collected over 6, 12 and 18 weeks. Fecal DNA was amplified across the 16S rRNA V4 region. At 18 weeks, kidney stone formation was visualized by Faxitron and blindly assessed by three investigators. After 18 weeks, urine calcium and oxalate decreased with Bactrim compared to CTL and Cipro. Urine pH increased with Bactrim compared to CTL and Cipro. Urine citrate increased with Cipro compared to CTL and decreased by half with Bactrim. Calcification increased with Bactrim compared to CTL and Cipro. Increased microbial diversity correlated with decreased urinary oxalate in all animals (R = − 0.46, p = 0.006). A potential microbial network emerged as significantly associated with shifts in urinary pH. Bactrim and Cipro differentially altered the GMB of GHS rats. The Bactrim group experienced a decrease in urine calcium, increased CaP supersaturation and increased calcification. The GMB is likely a contributing factor to changes in urine chemistry, supersaturation and stone risk. Further investigation is required to fully understand the association between antibiotics, the GMB and kidney stone formation. [ABSTRACT FROM AUTHOR]

To determine whether patients with ureteral stones received different standard of care in the emergency department (ED) according to various sociodemographic factors. We conducted a retrospective study of patients presenting to EDs in a large tertiary-care hospital in the Bronx, New York with a diagnosis of ureteral stones. Electronic chart review was used to assess each patient's ED course and to gather socio-demographic information. The primary outcomes of interest were administration of pain medication, prescription of alpha-1 antagonists to facilitate stone passage, and whether or not patients received CT scan or ultrasound. Associations of these outcomes with age categories, sex, race/ethnicity, BMI category, socioeconomic status and insurance status were examined using multivariate logistic regression models. 1200 patients were included in this analysis of which 616 (51%) were women. A large proportion of patients were minorities: 40% Hispanic, 15% non-Hispanic Black, and 20% other/multiracial. Patients aged 55–64 years and those 65 or older were less likely to receive pain medication compared to patients < 35 years (OR = 0.48, 95% CI 0.27–0.86, p = 0.01 and OR = 0.46, 95% CI 0.21–1.00, p = 0.05, respectively). Women were less likely than men to undergo any form of diagnostic imaging (OR = 0.52, 95% CI 0.35–0.76, p = 0.001). Similarly, patients in the lowest quintile of SES received less imaging than patients in the highest SES group (OR = 0.50, 95% CI 0.27–0.90, p = 0.02). Finally, women were less likely to receive alpha blockade compared to men (OR = 0.68, 95% CI 0.49–0.92, p = 0.014). Multiple disparities exist among patients presenting to the emergency department for ureteral stones. [ABSTRACT FROM AUTHOR]

To compare renal functional outcomes in patients with and without chronic kidney disease (CKD) to identify predictors of change in renal function after percutaneous nephrolithotomy (PCNL). We reviewed patients who underwent PCNL by a single surgeon over 3.5 years. Patients' pre- and post-operative Glomerular Filtration Rate (GFR) was calculated. Baseline GFR < 60 ml/min/1.73 m2 (stage ≥ 3 CKD) defined our CKD cohort. Patients' baseline renal function, comorbidities, stone parameters, and intra-operative variables were analyzed to determine the relationship with post-operative renal function after PCNL by multivariate analysis. 202 patients were analyzed. Mean follow-up time was 16 months. At baseline, 163 (80.7%) patients were free of CKD and 39 (19.3%) had CKD. Patients without CKD had an overall decrease in GFR from 105.6 to 103.3 ml/min/1.73 m2 (p = 0.494). 14/163 (8.6%) non-CKD patients experienced a significant decline in renal function after PCNL; 7/163 (4.3%) developed de novo CKD and 7 had a ≥ 30% decline in GFR. Patients with CKD had an overall increase in mean GFR post-operatively, from 47.3 to 54.0 ml/min/m2 (p = 0.067). Two in this cohort (5.1%) experienced a > 30% decline in renal function post-operatively. Age, gender, African American race, presence of comorbidities and pre-operative CKD were not significant predictors of renal function post-operatively on multivariate analysis. PCNL in this cohort appears GFR neutral in the setting of baseline CKD. CKD was not predictive of renal functional decline after PCNL. Given that stone disease carries a high recurrence rate and that CKD is associated with stone formers, further investigation into predictors of renal function change after PCNL is warranted. [ABSTRACT FROM AUTHOR]

Purpose of Review: With recent advances in sequencing technologies and increasing research into the gut microbiome (GMB), studies have revealed associations between the GMB and urinary stone disease (USD). We sought to determine whether the evidence pointed towards a few specific gut bacteria or the broader GMB network is seemingly responsible for this relationship. Recent Findings: Initially, Oxalobacter formigenes (OF) was pursued as the main link between GMB and USD given its ability to degrade oxalate in the gut. However, the latest studies consistently suggest that the entire GMB is much more likely to be involved in handling oxalate absorption and other risk factors for urinary stone formation, rather than just a few microbiota. Summary: The GMB has complex networks that are likely involved in the pathophysiology of USD, although the causal mechanisms remain unclear. With increasing interest and research, potential modalities that act on the GMB may help to prevent incidence of USD. [ABSTRACT FROM AUTHOR]