The medical and surgical management of kidney stones is one of the most common functions of the urologist. Management choices are often nuanced, involving the decision to embark on one surgical plan among several options. As the wider medical community critically evaluates the care we provide to an increasingly diverse population, it will be important to examine patient outcomes with a particular focus on ensuring equitable care. This review examines the influence of social parameters on the care of kidney stone patients. The dearth of literature in this area warrants rigorous studies on the relationship between race as well as socioeconomic status and the management of kidney stone disease.

Introduction: American Urological Association (AUA) guidelines recommend percutaneous nephrolithotomy (PCNL) for total stone burden greater than 20 mm, yet it is unclear if the number of stones affects adherence to this guideline. We aim to assess the impact of stone multiplicity on the choice of ureteroscopy (URS) vs PCNL as a first-line therapy for patients with high burden (>20 mm), and examine whether the AUA guideline-discordant care impacts patient outcomes. Materials and Methods: Data were collected from the Registry for Stones of the Kidney and Ureter (ReSKU) database, a prospectively collected registry of patients with stone disease. Multivariate logistic regression (MLR) was used to estimate the association between stone multiplicity and the decision to perform URS for high stone burden (>20 mm) patients. MLR was further used to estimate the association between performing URS and the following outcomes: stone-free rate, need for a second operation, and complications. Postoperative hospital stay was compared between patients receiving URS vs PCNL using Student's t-test. Results: One hundred twenty-five patients were included in this analysis. For patients with total stone burden exceeding 20 mm, those with more than three stones had roughly nine times the likelihood of undergoing URS over PCNL compared with patients with a single stone (adjusted odds ratio 9.21, confidence interval [95% CI] 2.55-40.58, p = 0.001). Stone-free rates, Clavien-Dindo scores, and frequency of second-look operations did not differ significantly between URS and PCNL patients. URS patients were discharged an average of 1.26 days earlier than patients who received PCNL (95% CI 0.72-1.81, p < 0.001). Discussion: Stone multiplicity strongly predicts which patients with stone burden >20 mm will undergo URS and who will undergo PCNL. These deviations from AUA guidelines do not appear to worsen patient outcomes. These results suggest that careful consideration of each patient may warrant deviation from guidelines.

OBJECTIVE: To determine social factors associated with advanced stone disease (defined as unilateral stone burden >2 cm) at time of presentation to a regional stone referral center. Little is known about social determinants of urolithiasis. We hypothesize that socioeconomic factors impact kidney stone severity at intake to referral centers. METHODS: A retrospective review of the prospectively collected data from the Registry for Stones of the Kidney and Ureter from 2015 to 2018 was conducted to evaluate patient characteristics predictive of having a large (>2 cm) unilateral kidney stone. Data on patient age, gender, body mass index, diabetes, race, language, education level, infection, distance, income, referring regional urologist density, American Society of Anesthesiologists score, and stone analysis were evaluated. RESULTS: Complete imaging and patient variable data was present in 650 of 1142 patients including 197 patients with unilateral stone burden >2 cm. On multivariate analysis, obesity, lower education level, increased distance from the referral center, and symptoms of infection predicted for unilateral stone burden greater than 2 cm. Among 191 patients with stone analysis data present, stone type, income, and urologist density predicted for unilateral stone burden greater than 2 cm. CONCLUSION: In addition to known biological risk factors, patients with lower education levels and from regions of lower mean income were found to be more likely to present to our tertiary care center with stone burden greater than 2 cm. More research is needed to elucidate the social and societal determinants of advanced stone disease and the impact this has on population costs for stone treatment.

Introduction: American Urological Association (AUA) guidelines recommend percutaneous nephrolithotomy (PCNL) for total stone burden greater than 20 mm, yet it is unclear if the number of stones affects adherence to this guideline. We aim to assess the impact of stone multiplicity on the choice of ureteroscopy (URS) vs PCNL as a first-line therapy for patients with high burden (>20 mm), and examine whether the AUA guideline-discordant care impacts patient outcomes. Materials and Methods: Data were collected from the Registry for Stones of the Kidney and Ureter (ReSKU) database, a prospectively collected registry of patients with stone disease. Multivariate logistic regression (MLR) was used to estimate the association between stone multiplicity and the decision to perform URS for high stone burden (>20 mm) patients. MLR was further used to estimate the association between performing URS and the following outcomes: stone-free rate, need for a second operation, and complications. Postoperative hospital stay was compared between patients receiving URS vs PCNL using Student's t-test. Results: One hundred twenty-five patients were included in this analysis. For patients with total stone burden exceeding 20 mm, those with more than three stones had roughly nine times the likelihood of undergoing URS over PCNL compared with patients with a single stone (adjusted odds ratio 9.21, confidence interval [95% CI] 2.55-40.58, p = 0.001). Stone-free rates, Clavien-Dindo scores, and frequency of second-look operations did not differ significantly between URS and PCNL patients. URS patients were discharged an average of 1.26 days earlier than patients who received PCNL (95% CI 0.72-1.81, p < 0.001). Discussion: Stone multiplicity strongly predicts which patients with stone burden >20 mm will undergo URS and who will undergo PCNL. These deviations from AUA guidelines do not appear to worsen patient outcomes. These results suggest that careful consideration of each patient may warrant deviation from guidelines.

OBJECTIVES:To compare clinical outcomes in patients who underwent percutaneous nephrolithotomy (PCNL) with renal tract dilatation performed under fluoroscopic guidance vs renal tract dilatation with ultrasound guidance. PATIENTS AND METHODS:We conducted a prospective observational cohort study, enrolling successive patients undergoing PCNL between July 2015 and March 2018. Included in this retrospective analysis were cases where the renal puncture was successfully obtained with ultrasound guidance. Cases were then grouped according to whether fluoroscopy was used to guide renal tract dilatation or not. All statistical analyses were performed using Stata version 15.1 including univariate (Fisher's exact test, Welch's t-test) and multivariate analyses (binomial logistic regression, ordinal logistic regression, and linear regression). RESULTS:A total of 176 patients underwent PCNL with successful ultrasonography-guided renal puncture, of whom 38 and 138 underwent renal tract dilatation with fluoroscopic vs ultrasound guidance, respectively. There were no statistically significant differences in patient age, gender, body mass index (BMI), preoperative hydronephrosis, stone burden, procedure laterality, number of dilated tracts, and calyceal puncture location between the two groups. Among ultrasound tract dilatations, a higher proportion of patients were placed in the modified dorsal lithotomy position as opposed to prone, and a significantly shorter operating time was observed. Only modified dorsal lithotomy position remained statistically significant after multivariate regression. There were no statistically significant differences in postoperative stone clearance, complication rate, or intra-operative estimated blood loss. A 5-unit increase in a patient's BMI was associated with 30% greater odds of increasingly severe Clavien-Dindo complications. A 5-mm decrease in the preoperative stone burden was associated with 20% greater odds of stone-free status. No variables predicted estimated blood loss with statistical significance. CONCLUSIONS:Renal tract dilatation can be safely performed in the absence of fluoroscopic guidance. Compared to using fluoroscopy, the present study demonstrated that ultrasonography-guided dilatations can be safely performed without higher complication or bleeding rates. This can be done using a variety of surgical positions, and future studies centred on improving dilatation techniques could be of impactful clinical value.

Introduction and Objectives: Lack of access to urologic specialists is approaching crisis levels as the number of urologists is decreasing, while the demand for urologic care is increasing. The financial implications of this have not been explored. The objective of this study is to examine the impact of access and other patient factors on cost to treat urolithiasis. We hypothesized that markers of poor access would associate with higher costs of surgical encounters for patients presenting with urolithiasis. Methods: A retrospective review of prospectively collected data from the Registry for Stones of the Kidney and Ureter (ReSKU) from September 2015 to July 2018 was conducted to investigate characteristics of surgical patients treated for urinary stone disease. Univariate analysis was performed using the Welch two-sample t-test. Multivariate analysis was performed using logistic regression. Statistical analysis was performed in R version 3.5. Results: When taking into account age, delayed presentation, procedure type, stone size >20 mm, American Society of Anesthesiologists (ASA) code, gender, race, income, distance, urologist density, body mass index, diabetes, infection, education, language, insurance, and stone complexity, patients undergoing percutaneous nephrolithotomy procedure (p < 0.001; odds ratio [OR] 12.9, confidence interval [CI] 4.05-48.5), urologist density in the bottom quartile (p = 0.014; OR 4.66, CI 1.40-16.9), diabetes (p = 0.018; OR 4.38, CI 1.32-15.6), and infection (p = 0.007; OR 4.51, CI 1.55-14.0) were the only variables statistically significant for association with top quartile of total cost. Conclusions: Surgical encounter costs are largely dictated by patient clinical factors, but low regional urologist density appears to independently predicted for high-cost stone surgery. Increasing patients' access to a urologist may prove to be financially beneficial in the longitudinal reduction in health care costs for stone disease.

Focal adhesion kinase (FAK) is an important mediator of extracellular matrix-integrin mechano-signal transduction that regulates cell motility, survival, and proliferation. As such, FAK is being investigated as a potential therapeutic target for malignant and fibrotic diseases, and numerous clinical trials of FAK inhibitors are underway. The function of FAK in nonmalignant, nonmotile epithelial cells is not well understood. We previously showed that hepatocytes demonstrated activated FAK near stiff collagen tracts in fibrotic livers. In this study, we examined the role of liver epithelial FAK by inducing fibrotic liver disease in mice with liver epithelial FAK deficiency. We found that mice that lacked FAK in liver epithelial cells developed more severe liver injury and worse fibrosis as compared with controls. Increased fibrosis in liver epithelial FAK-deficient mice was linked to the activation of several profibrotic pathways, including the hedgehog/smoothened pathway. FAK-deficient hepatocytes produced increased Indian hedgehog in a manner dependent on matrix stiffness. Furthermore, expression of the hedgehog receptor, smoothened, was increased in macrophages and biliary cells of hepatocyte-specific FAK-deficient fibrotic livers. These results indicate that liver epithelial FAK has important regulatory roles in the response to liver injury and progression of fibrosis.

Objective

To determine if limited food access census tracts and food swamp census tracts are associated with increased risk for repeat kidney stone surgery. And to elucidate the relationship between community-level food retail environment relative to community-level income on repeat stone surgery over time.

Methods

Data were abstracted from the University of California, San Francisco Information Commons. Adult patients were included if they underwent at least one urologic stone procedure. Census tracts from available geographical data were mapped using Food Access Research Atlas data from the United States Department of Agriculture Economic Research Service. Kaplan-Meier curves were employed to illustrate time to a second surgical procedure over 5 years, and log-rank tests were used to test for statistically significant differences. A multivariate Cox regression model was used to generate hazard ratios for undergoing second surgery by group.

Results

A total of 1496 patients were included in this analysis. Repeat stone surgery occurred in 324 patients. Kaplan-Meier curves demonstrated a statistically significant difference in curves depicting patients living in low income census tracts (LICTs) vs those not living in LICTs (P <.001). On Cox regression models, patients in LICTs had significantly higher risk of undergoing repeat surgery (P = .011). Patients from limited food access census tracts and food swamp census tracts did not have a significantly higher adjusted risk of undergoing second surgery (P = .11 and P = .88, respectively).

Conclusion

Income more so than food access associates with increased risk of repeat kidney stone surgery. Further research is needed to explore the interaction between low socioeconomic status and kidney stone outcomes.

Objective

To determine social factors associated with advanced stone disease (defined as unilateral stone burden >2 cm) at time of presentation to a regional stone referral center. Little is known about social determinants of urolithiasis. We hypothesize that socioeconomic factors impact kidney stone severity at intake to referral centers.

Methods

A retrospective review of the prospectively collected data from the Registry for Stones of the Kidney and Ureter from 2015 to 2018 was conducted to evaluate patient characteristics predictive of having a large (>2 cm) unilateral kidney stone. Data on patient age, gender, body mass index, diabetes, race, language, education level, infection, distance, income, referring regional urologist density, American Society of Anesthesiologists score, and stone analysis were evaluated.

Results

Complete imaging and patient variable data was present in 650 of 1142 patients including 197 patients with unilateral stone burden >2 cm. On multivariate analysis, obesity, lower education level, increased distance from the referral center, and symptoms of infection predicted for unilateral stone burden greater than 2 cm. Among 191 patients with stone analysis data present, stone type, income, and urologist density predicted for unilateral stone burden greater than 2 cm.

Conclusion

In addition to known biological risk factors, patients with lower education levels and from regions of lower mean income were found to be more likely to present to our tertiary care center with stone burden greater than 2 cm. More research is needed to elucidate the social and societal determinants of advanced stone disease and the impact this has on population costs for stone treatment.

Objective

To further elucidate the relationship between low socioeconomic status (SES) and larger, more complex stones requiring staged surgical interventions. Specifically, we aimed to determine if underinsurance (Medicaid, Medicare, and self-pay insurance types) is associated with multiple surgeries within 1 year.

Methods

We performed a retrospective longitudinal analysis of prospectively collected data from the California statewide Department of Health Care Access and Information (HCAI) dataset. We included adult patients who had their first recorded kidney stone encounter between 2009 and 2018 and underwent at least 1 urologic stone procedure. We followed these patients within the dataset for one year after their initial surgery to assess for factors predicting multiple surgical treatments for stones.

Results

A total of 156,319 adults were included in the study. The proportions of individuals in private insurance, Medicaid, Medicare and self-pay/indigent groups differed by the presence or absence of additional surgeries (64.0%, 13.5%, 19.4%, and 0.1%, vs 70.3%, 10.1%, 16.6%, and 0.1%, respectively). Compared to private insurance, Medicaid (1.46 [1.40-1.53] P < .001) and Medicare (1.15 [1.10-1.20] P < .001) insurance types were associated with significantly greater odds of multiple surgeries, whereas no significant association was seen in the self-pay/indigent insurance type (1.35 [0.83-2.19], P = 1.0).

Conclusion

In a statewide, California database from 2009 to 2018, underinsured adults had higher odds of undergoing a second procedure for kidney stones within 1 year of initial surgical treatment. This study adds to the expanding body of literature linking suboptimal healthcare access and disparate outcomes for kidney stone patients.