Use of Cinacalcet for the Management of Primary Hyperparathyroidism in Pregnancy.

Primary hyperparathyroidism in pregnancy is uncommon. Consequently, there are no randomized controlled studies that address treatment of primary hyperparathyroidism in pregnancy, and the efficacy and safety of medical management with cinacalcet in this setting is unknown. We report a case of a 28-year-old woman with primary hyperparathyroidism and hypercalcemia that worsened during her third trimester of pregnancy. Cinacalcet led to achievement of normocalcemia, allowing the delay of parathyroidectomy until after delivery of the baby. We also review the published literature on cinacalcet use in the management of primary hyperparathyroidism during pregnancy. Cinacalcet is typically reserved for pregnant patients with severe and symptomatic hypercalcemia, primarily serving as a last resort to delay parathyroidectomy until either the second trimester or the postpartum period.

Patient Characteristics, Management, and Outcomes in a Novel Cohort of Primary Hyperparathyroidism.

Context: Primary hyperparathyroidism (PHPT) increases the risk of bone loss, debilitating fractures, kidney stones, impaired renal function, and neurocognitive symptoms. Studies describing the natural history of PHPT have been limited to small samples, single institutions, or specific populations. Objective: We assessed the natural history of PHPT through a large, diverse national cohort from an electronic health record dataset representing more than 100 million patients. Methods: The TriNetX database was queried for adult patients with PHPT. We extracted demographics, comorbidities, and longitudinal biochemistries. Primary outcomes included major osteoporotic fracture (MOF) and chronic kidney disease (CKD). Outcomes were stratified by treatment strategy (surgical parathyroidectomy [PTX] vs nonsurgical) and age. Results: Among 50 958 patients with PHPT, 26.5% were treated surgically at a median of 0.3 years postdiagnosis. At diagnosis, median age was 65 years, 74.0% were female, and median calcium level was 10.9 mg/dL. Black and older patients underwent PTX less frequently than White and younger patients. MOF 10-year incidence was 5.20% (PTX) and 7.91% (nonsurgical), with median 1.7-year delay with PTX compared to nonsurgical. PTX-associated MOF absolute risk reduction was 0.83% (age < 65 years) and 3.33% (age ≥ 65 years). CKD 10-year incidence was 21.2% (PTX) and 33.6% (nonsurgical), with median 1.9-year delay with PTX. PTX-associated CKD absolute risk reduction was 12.2% (age < 65 years) and 9.5% (age ≥ 65 years). Conclusion: We report 1 of the largest, representative, population-based natural histories of PHPT with different management strategies. A minority of patients underwent PTX, especially in older age. Patients managed surgically had lower incidence of fracture and CKD, and older patients experienced differential benefit.

Using structured problem solving to promote fluid consumption in the prevention of urinary stones with hydration (PUSH) trial.

BACKGROUND: Structured Problem Solving (SPS) is a patient-centered approach to promoting behavior change that relies on productive collaboration between coaches and participants and reinforces participant autonomy. We aimed to describe the design, implementation, and assessment of SPS in the multicenter Prevention of Urinary Stones with Hydration (PUSH) randomized trial. METHODS: In the PUSH trial, individuals with a history of urinary stone disease and low urine output were randomized to control versus a multicomponent intervention including SPS that was designed to promote fluid consumption and thereby prevent recurrent stones. We provide details specifically about training and fidelity assessment of the SPS coaches. We report on implementation experiences related to SPS during the initial conduct of the trial. RESULTS: With training and fidelity assessment, coaches in the PUSH trial applied SPS to help participants overcome barriers to fluid consumption. In some cases, coaches faced implementation barriers such as variable participant engagement that required tailoring their work with specific participants. The coaches also faced challenges including balancing rapport with problem solving, and role clarity for the coaches. CONCLUSIONS: We adapted SPS to the setting of kidney stone prevention and overcame challenges in implementation, such as variable patient engagement. Tools from the PUSH trial may be useful to apply to other health behavior change settings in nephrology and other areas of clinical care. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT03244189.

Patients' Experiences With the Removal of a Ureteral Stent: Insights From In-depth Interviews With Participants in the USDRN STENTS Qualitative Cohort Study.

OBJECTIVE: To describe the experiences of patients undergoing stent removal in the USDRN Study to Enhance Understanding of Stent-Associated Symptoms (STENTS), a prospective, observational cohort study of patients with short-term ureteral stent placement post-ureteroscopy. METHODS: We conducted a qualitative descriptive study using in-depth interviews. Participants reflected on (1) painful or bothersome aspects of stent removal, (2) symptoms immediately after removal, and (3) symptoms in the days following removal. Interviews were audio-recorded, transcribed, and analyzed using applied thematic analysis. RESULTS: The 38 participants interviewed were aged 13-77 years, 55% female, and 95% White. Interviews were conducted 7-30 days after stent removal. Almost all participants (n = 31) described that they experienced either pain or discomfort during stent removal, but for most (n = 25) pain was of short duration. Many participants (n = 21) described anticipatory anxiety related to the procedure, and several (n = 11) discussed discomfort arising from lack of privacy or feeling exposed. Interactions with medical providers often helped put participants at ease, but also increased discomfort for some. Following stent removal, several participants described lingering pain and/or urinary symptoms, but these largely resolved within 24 hours. A few participants described symptoms persisting for more than a day post stent removal. CONCLUSION: These findings on patients' experiences during and shortly after ureteral stent removal, particularly the psychological distress they experienced, identify opportunities for improvement in patient care. Clear communication from providers about what to expect with the removal procedure, and the possibility of delayed pain, may help patients adapt to discomfort.

The Patient Voice: Stent Experiences After Ureteroscopy-Insights from In-Depth Interviews with Participants in the USDRN STENTS Nested Qualitative Cohort Study.

Purpose: Ureteral stents are commonly used after ureteroscopy and cause significant discomfort, yet qualitative perspectives on patients' stent experiences remain unknown. We describe psychological, functional, and interpersonal effects of post-ureteroscopy stents and whether additional patient-reported assessments may be needed. Materials and Methods: Using a qualitative descriptive study design, we conducted in-depth interviews with a nested cohort of participants in the STudy to Enhance uNderstanding of sTent-associated Symptoms (STENTS). Participants shared their symptoms with a post-ureteroscopy stent and described symptom bother and impact on daily activities. All interviews were audio-recorded, transcribed, and analyzed using applied thematic analysis. During analysis, participants' experiences with interference in daily activities were categorized into three groups based on their impact: minimal, moderate, and substantial. Results: All 39 participants experienced pain, although descriptions varied and differentiated between feelings of pain vs discomfort. Almost all experienced urinary symptoms. Only a few reported other physical symptoms, although several psychological aspects were identified. In the areas of sleep, mood, life enjoyment, work, exercise, activities of daily living, driving, childcare, and leisure/social activities, the stent had little impact on daily living among participants placed in the minimal group (n = 12) and far greater impact for participants in the substantial group (n = 8). For patients in the moderate group (n = 19), some daily activities were moderately or substantially affected, whereas other activities were minimally affected. Conclusions: Counseling to better prepare patients for the impact of stent-associated symptoms may help mitigate symptom burden. While existing instruments adequately cover most symptoms, additional assessments for other domains, particularly psychological factors, may be needed.

Risk Factors for Increased Stent-associated Symptoms Following Ureteroscopy for Urinary Stones: Results From STENTS.

PURPOSE: The STudy to Enhance uNderstanding of sTent-associated Symptoms sought to identify risk factors for pain and urinary symptoms, as well as how these symptoms interfere with daily activities after ureteroscopy for stone treatment. MATERIALS AND METHODS: This prospective observational cohort study enrolled patients aged ≥12 years undergoing ureteroscopy with ureteral stent for stone treatment at 4 clinical centers. Participants reported symptoms at baseline; on postoperative days 1, 3, 5; at stent removal; and day 30 post-stent removal. Outcomes of pain intensity, pain interference, urinary symptoms, and bother were captured with multiple instruments. Multivariable analyses using mixed-effects linear regression models were identified characteristics associated with increased stent-associated symptoms. RESULTS: A total of 424 participants were enrolled. Mean age was 49 years (SD 17); 47% were female. Participants experienced a marked increase in stent-associated symptoms on postoperative day 1. While pain intensity decreased ∼50% from postoperative day 1 to postoperative day 5, interference due to pain remained persistently elevated. In multivariable analysis, older age was associated with lower pain intensity (P = .004). Having chronic pain conditions (P < .001), prior severe stent pain (P = .021), and depressive symptoms at baseline (P < .001) were each associated with higher pain intensity. Neither sex, stone location, ureteral access sheath use, nor stent characteristics were drivers of stent-associated symptoms. CONCLUSIONS: In this multicenter cohort, interference persisted even as pain intensity decreased. Patient factors (eg, age, depression) rather than surgical factors were associated with symptom intensity. These findings provide a foundation for patient-centered care and highlight potential targets for efforts to mitigate the burden of stent-associated symptoms.

Type 4 renal tubular acidosis and uric acid nephrolithiasis: two faces of the same coin?

PURPOSE OF REVIEW: The present review summarizes findings of recent studies examining the epidemiology, pathophysiology, and treatment of type 4 renal tubular acidosis (RTA) and uric acid nephrolithiasis, two conditions characterized by an abnormally acidic urine. RECENT FINDINGS: Both type 4 RTA and uric acid nephrolithiasis disproportionately occur in patients with type 2 diabetes and/or chronic kidney disease. Biochemically, both conditions are associated with reduced renal ammonium excretion resulting in impaired urinary buffering and low urine pH. Reduced ammoniagenesis is postulated to result from hyperkalemia in type 4 RTA and from insulin resistance and fat accumulation in the renal proximal tubule in uric acid nephrolithiasis. The typical biochemical findings of hyperkalemia and systemic acidosis of type 4 RTA are rarely reported in uric acid stone formers. Additional clinical differences between the two conditions include findings of higher urinary uric acid excretion and consequent urinary uric acid supersaturation in uric acid stone formers but not in type 4 RTA. SUMMARY: Type 4 RTA and uric acid nephrolithiasis share several epidemiological, clinical, and biochemical features. Although both conditions may be manifestations of diabetes mellitus and thus have a large at-risk population, the means to the shared biochemical finding of overly acidic urine are different. This difference in pathophysiology may explain the dissimilarity in the prevalence of kidney stone formation.

Bone health outcomes in post-lung transplant patients with cystic fibrosis.

BACKGROUND: Osteoporosis is a common comorbidity in patients with cystic fibrosis (CF). Although lung transplantation (LTx) improves quality of life of CF patients, there is little research examining long-term bone health outcomes following LTx in these patients. METHODS: Data were collected on 59 patients who underwent LTx between 2006 and 2019, including 30 with CF and 29 without CF. We compared baseline characteristics, long-term bone mineral density (BMD) trends, and fracture incidence between the two patient populations, and examined factors associated with post-LTx fractures in CF patients. RESULTS: Compared with non-CF patients, patients with CF were younger, had lower body mass index, and lower baseline BMD Z-scores at the lumbar spine, femoral neck, and total hip (all p<0.001). BMD at all sites declined in both groups in the first year post-LTx. In subsequent years, CF patients exhibited better BMD recovery relative to pre-transplantation, but continued to have lower BMD post-LTx. Post-transplant fractures occurred in 30% and 34% of CF and non-CF patients, respectively. CF patients who developed fractures after LTx had significantly lower BMD and lower pre-transplantation percent predicted forced expiratory volume in one second (FEV1%). CONCLUSIONS: Although CF patients exhibit better BMD recovery following LTx compared to their non-CF counterparts, CF patients start with significantly lower pre-LTx BMD and experience a similarly high rate of post-LTx fractures. These findings highlight the unique contribution of the CF disease process to bone health, as well as a clear need for better prevention and treatment of osteoporosis in CF patients before and after LTx.

Evaluation of an association between RANKL and OPG with bone disease in people with cystic fibrosis.

BACKGROUND: As people with Cystic Fibrosis (CF) live longer, extra-pulmonary complications such as CF-related bone disease (CFBD) are becoming increasingly important. The etiology of CFBD is poorly understood but is likely multifactorial. Bones undergo continuous remodeling via pathways including RANK (receptor activator of NF-κB)/sRANKL (soluble ligand)/OPG (osteoprotegerin). We sought to examine the association between sRANKL (stimulant of osteoclastogenesis) and OPG levels (inhibitor of osteoclast formation) and CFBD to investigate their potential utility as biomarkers of bone turnover in people with CF. METHODS: We evaluated sRANKL and OPG in plasma from people with CF and healthy controls (HC) and compared levels in those with CF to bone mineral density results. We used univariable and multivariable analysis to account for factors that may impact sRANKL and OPG. RESULTS: We found a higher median [IQR] sRANKL 10,896pg/mL [5,781-24,243] CF; 2,406pg.mL [659.50-5,042] HC; p= 0.0009), lower OPG 56.68pg/mL [36.28-124.70] CF; 583.20pg/mL [421.30-675.10] HC; p < 0.0001), and higher RANKL/OPG in people with CF no BD than in HC (p < 0.0001). Furthermore, we found a higher RANKL/OPG ratio 407.50pg/mL [214.40-602.60] CFBD; 177.70pg/mL [131.50-239.70] CF no BD; p = 0.007) in people with CFBD versus CF without bone disease. This difference persisted after adjusting for variables thought to impact bone health. CONCLUSIONS: The current screening recommendations of imaging for CFBD may miss important markers of bone turnover such as the RANKL/OPG ratio. These findings support the investigation of therapies that modulate the RANK/RANKL/OPG pathway as potential therapeutic targets for bone disease in CF.

Alkali Citrate Content of Common Over-the-Counter and Medical Food Supplements.

Objective: Potassium citrate effectively decreases kidney stone recurrence, but it is costly and associated with side effects. While several over-the-counter supplements and medical foods purport to provide sufficient citrate to prevent recurrent stones, corroborating data on their actual citrate content is limited. Materials and Methods: Nine common nonprescription products were purchased online. Reported citrate content was obtained from packaging, promotional materials, or ingredient labels. Using a single serving of each product, actual citrate, sodium, potassium, calcium, magnesium, and oxalate content was measured using spectrophotometry and chromatography. Total alkali citrate, cost, and amounts of each component per 10 mEq of alkali citrate were also calculated. Results: Nearly all products contained more citrate than advertised, except for Litholyte® powder, Litholyte® Coffee, and Horbäach® potassium citrate. Per serving, Moonstone® powder, LithoBalance™, and KSP tabs™ contained the most citrate (means of 63.9, 33.5, and 26.9 mEq, respectively). Moonstone and LithoBalance had the greatest discrepancy between total citrate and alkali citrate (15.7 and 11.8 mEq per serving, respectively). NOW® potassium citrate was least expensive ($0.04/10 mEq alkali citrate). KSP tabs delivered the most daily sodium (mean 158 mg/10 mEq alkali citrate, Litholyte Coffee provided the most potassium (mean of 13 mEq/10 mEq alkali citrate), and Kidney COP® provided the most calcium (mean 147 mg/10 mEq alkali citrate). Conclusion: Some common over-the-counter products contain sufficient alkali to potentially promote a citraturic response; Moonstone provides the most alkali citrate, but at a higher cost than other products. Sodium, potassium, and calcium from these products must also be considered in daily consumption.

Romosozumab-aqqg in the Treatment of Osteoporosis in a Patient With Hypophosphatasia.

Hypophosphatasia is a rare, inherited condition that causes osteomalacia and recurrent fractures. Therapeutic options for osteoporosis in patients with hypophosphatasia are limited because of concerns for a greater likelihood of atypical femoral fractures with antiresorptive agents. We report here the case of a patient with hypophosphatasia and osteoporosis who was treated with romosozumab-aqqg (Romo). An 81-year-old woman presented for management of osteoporosis with multiple fractures. She experienced a decline in bone mineral density over 20 years despite sequential osteoporosis treatment with oral bisphosphonates, hormone replacement therapy, teriparatide, and denosumab. Hypophosphatasia was suspected because of low serum alkaline phosphatase levels and was confirmed by genetic testing. After diagnosing hypophosphatasia, bone mineral density continued to decline and a trial of Romo was begun. After 1 year of Romo therapy, bone mineral density improved by 21%, and 10% at the lumbar spine and total hip, respectively. These changes were substantially greater than what she had experienced with prior teriparatide therapy. Blood alkaline phosphatase remained low on Romo. To our knowledge, this is the first report of a patient with hypophosphatasia and osteoporosis treated with Romo. In our patient, Romo did not significantly impact serum alkaline phosphatase, but improved bone mineral density significantly. In conclusion, Romo is a potential treatment option for osteoporosis in patients with hypophosphatasia for whom limited alternatives exist.

Preclinical and Clinical Evidence of Effect of Acid on Bone Health.

Acid can have ill effect on bone health in the absence of frank clinical acidosis but affecting the bone mioneral matrix and bone cells via complex pathways botyh ascute;y and chronically. While the reaction of bone to an acid load is conserved in evolution and is adaptive, the capacity can be overwhelmed resulting in dire consequences. The preclinical an clincl evidence of the acdi effect on bone is very convincing and the clinical evidence in both association and interventiopn studies are also quite credible, The adverse effects of acid on bone is underappreoicated, under-investigated, and the potential benefits of alkali therapy is not generrally known.

Associations of Obesity and Neighborhood Factors With Urinary Stone Parameters.

INTRODUCTION: Obesity is associated with kidney stone disease, but it is unknown whether this association differs by SES. This study assessed the extent to which obesity and neighborhood characteristics jointly contribute to urinary risk factors for kidney stone disease. METHODS: This was a retrospective analysis of adult patients with kidney stone disease evaluated with 24-hour urine collection (2001-2020). Neighborhood-level socioeconomic data were obtained for a principal component analysis, which identified 3 linearly independent factors. Associations between these factors and 24-hour urine measurements were assessed using linear regression as well as groupings of 24-hour urine results using multivariable logistic regression. Finally, multiplicative interactions were assessed testing effect modification by obesity, and analyses stratified by obesity were performed. Analyses were performed in 2021. RESULTS: In total, 1,264 patients met the study criteria. Factors retained on principal component analysis represented SES, family structure, and housing characteristics. On linear regression, there was a significant inverse correlation between SES and 24-hour urine sodium (p=0.0002). On multivariable logistic regression, obesity was associated with increased odds of multiple stone risk factors (OR=1.61; 95% CI=1.15, 2.26) and multiple dietary factors (OR=1.33; 95% CI=1.06, 1.67). No significant and consistent multiplicative interactions were observed between obesity and quartiles of neighborhood SES, family structure, or housing characteristics. CONCLUSIONS: Obesity was associated with the presence of multiple stone risk factors and multiple dietary factors; however, the strength and magnitude of these associations did not vary significantly by neighborhood SES, family structure, and housing characteristics.

Quality of life impact and recovery after ureteroscopy and stent insertion: insights from daily surveys in STENTS.

BACKGROUND: Our objective was to describe day-to-day evolution and variations in patient-reported stent-associated symptoms (SAS) in the STudy to Enhance uNderstanding of sTent-associated Symptoms (STENTS), a prospective multicenter observational cohort study, using multiple instruments with conceptual overlap in various domains. METHODS: In a nested cohort of the STENTS study, the initial 40 participants having unilateral ureteroscopy (URS) and stent placement underwent daily assessment of self-reported measures using the Brief Pain Inventory short form, Patient-Reported Outcome Measurement Information System measures for pain severity and pain interference, the Urinary Score of the Ureteral Stent Symptom Questionnaire, and Symptoms of Lower Urinary Tract Dysfunction Research Network Symptom Index. Pain intensity, pain interference, urinary symptoms, and bother were obtained preoperatively, daily until stent removal, and at postoperative day (POD) 30. RESULTS: The median age was 44 years (IQR 29,58), and 53% were female. The size of the dominant stone was 7.5 mm (IQR 5,11), and 50% were located in the kidney. There was consistency among instruments assessing similar concepts. Pain intensity and urinary symptoms increased from baseline to POD 1 with apparent peaks in the first 2 days, remained elevated with stent in situ, and varied widely among individuals. Interference due to pain, and bother due to urinary symptoms, likewise demonstrated high individual variability. CONCLUSIONS: This first study investigating daily SAS allows for a more in-depth look at the lived experience after URS and the impact on quality of life. Different instruments measuring pain intensity, pain interference, and urinary symptoms produced consistent assessments of patients' experiences. The overall daily stability of pain and urinary symptoms after URS was also marked by high patient-level variation, suggesting an opportunity to identify characteristics associated with severe SAS after URS.

Androgen Deprivation Therapy Differentially Impacts Bone and Muscle in the Short Term in Physically Active Men With Prostate Cancer.

Androgen deprivation therapy (ADT) is a cornerstone of advanced prostate cancer (PCa) therapy. Its use is associated with a loss of bone mineral density (BMD) and a greater risk of falls and osteoporotic fractures. In this prospective cohort study, we examined the impact of ADT on muscle and bone strength in men initiating ADT for PCa. Participants were evaluated at three time points: immediately before (week 0), and 6 and 24 weeks after ADT initiation. Study measures included fasting blood levels (for markers of muscle and bone metabolic activity), MRI and QCT imaging (for muscle fat content, and bone density and architecture), and validated clinical tests of muscle strength and gait. Sixteen men completed all study visits. At baseline and throughout the study, participants exercised a median of four times/week, but still experienced weight gain (+2.0 kg at week 24 versus week 0, p = 0.004). Biochemically, all men sustained dramatic early and persistent reductions in sex hormones post-ADT, along with a progressive and significant increase in serum C-telopeptide of type I collagen (CTX, +84% at week 24 versus week 0). There was a trend for rise in serum sclerostin (p = 0.09) and interleukin 6 (IL-6) (p = 0.08), but no significant change in serum myostatin (p = 0.99). Volumetric BMD by QCT declined significantly at the femoral neck (-3.7% at week 24 versus week 0), particularly at the trabecular compartment. On MRI, there were no significant changes in thigh muscle fat fraction. On physical testing, men developed weaker grip strength, but experienced no worsening in lower extremity and lumbar spine muscle strength, or on functional tests of gait. In conclusion, in physically active men, ADT for 24 weeks results in a significant increase in bone resorption and reduction in BMD, but nonsignificant changes in thigh muscle quality (on imaging) or strength and gait (on functional testing). © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Disparities in Kidney Stone Disease: A Scoping Review.

PURPOSE: We reviewed the available evidence regarding health disparities in kidney stone disease to identify knowledge gaps in this area. MATERIALS AND METHODS: A literature search was conducted using PubMed®, Embase® and Scopus® limited to articles published in English from 1971 to 2020. Articles were selected based on their relevance to disparities in kidney stone disease among adults in the United States. RESULTS: Several large epidemiological studies suggest disproportionate increases in incidence and prevalence of kidney stone disease among women as well as Black and Hispanic individuals in the United States, whereas other studies of comparable size do not report racial and ethnic demographics. Numerous articles describe disparities in imaging utilization, metabolic workup completion, analgesia, surgical intervention, stone burden at presentation, surgical complications, followup, and quality of life based on race, ethnicity, socioeconomic status and place of residence. Differences in urinary parameters based on race, ethnicity and socioeconomic status may be explained by both dietary and physiological factors. All articles assessed had substantial risk of selection bias and confounding. CONCLUSIONS: Health disparities are present in many aspects of kidney stone disease. Further research should focus not only on characterization of these disparities but also on interventions to reduce or eliminate them.

Impact of age and renal function on urine chemistry in patients with calcium oxalate kidney stones.

Nephrolithiasis is associated with an increased risk of chronic kidney disease, and its incidence varies with age. However, little is known on the combined impact of aging and declining renal function on urinary risk factors for calcium oxalate stone formation. A retrospective analysis was performed on 24-h urine collections from 993 calcium oxalate stone-forming patients. We first tested for interactions between age and creatinine clearance on various urinary determinants of calcium oxalate nephrolithiasis, and then examined their separate and combined effects in univariable and multivariable analyses adjusting for demographic and biochemical covariates. We identified significant interactions between age and creatinine clearance in predicting 24-h urine pH, calcium, and citrate. In view of the small number of stone formers with low creatinine clearance, we limited further regression analyses to patients with creatinine clearance ≥ 60 mL/min. In multivariable analyses, urine citrate, oxalate, and total volume were positively correlated with age, whereas urine pH, citrate, calcium, oxalate, total volume, and RSR of calcium oxalate all significantly decreased with lower creatinine clearance. A decrease in creatinine clearance from 120 to 60 mL/min was associated with clinically significant decreases in the daily excretion rate of citrate (by 188 mg/day), calcium (by 33 mg/day), and oxalate (by 4 mg/day), and in RSR calcium oxalate (by 1.84). Age and creatinine clearance are significant and independent predictors of several urinary determinants of calcium oxalate nephrolithiasis. The impacts of aging and declining renal function should be considered during the management of calcium oxalate stone-forming patients.