Mineral density and bone remodelling markers in patients with calcium lithiasis

Risk factors for the comorbidity of osteoporosis/osteopenia and kidney stones: a cross-sectional study

Low femoral neck bone mineral density (BMD) was associated with the increased risk of kidney stones. Low dietary magnesium intake and increased serum alkaline phosphatase were associated with the increased risk of low femoral neck BMD in kidney stone formers.

PURPOSE

To evaluate whether low femoral neck bone mineral density (BMD) was associated with a higher risk of kidney stones, and identify risk factors for the comorbidity of osteoporosis/osteopenia and kidney stones.

METHODS

We analyzed individuals aged ≥ 20 years from National Health and Nutrition Examination Survey 2007-2020 data. Osteoporosis/osteopenia is defined as any T-score < -1.0 of femoral neck, total femoral, and mean lumbar spine (L1-L4) BMD. Dietary intakes (sodium, potassium, magnesium, calcium, phosphorus, calcium/phosphorus, vitamin D (25OHD2+25OHD3)) and serum parameters (sodium, potassium, calcium, phosphorus, bicarbonate, vitamin D, alkaline phosphatase (ALP)) were screened for identifying risk factors for the comorbidity.

RESULTS

The prevalence of comorbidity of osteoporosis/osteopenia and kidney stones was 4.82%. Femoral neck BMD T-score was negatively associated with the prevalence of kidney stones (n=11,864). Dietary magnesium intake, serum phosphorus, and bicarbonate were negatively associated with the comorbidity prevalence, and serum ALP was positively associated with the comorbidity prevalence (n=6978). Additionally, there remain significant associations of dietary magnesium intake, serum ALP, and bicarbonate with not only femoral neck BMD T-score (n=11331), but also the prevalence of kidney stones (n=23,111) in general population. Furthermore, dietary magnesium intake was positively correlated to femoral neck BMD T-score in stone formers (SFs), while serum ALP was negatively correlated to femoral neck BMD T-score in SFs (n=1163).

CONCLUSION

Low femoral neck BMD was closely associated with an increased risk of kidney stones. Low magnesium intake and increased serum ALP were associated with the increased risk of the comorbidity, as well as indicative of low femoral neck BMD T-score in SFs, which offered a clue to further clarify the mechanism leading to paradoxical calcification of bone resorption and kidney stones, and had the potential to perform personalized diagnostic workup for low BMD in SFs.

The Reciprocal Relationship between Osteoporosis and Renal Stones

Previous studies have proposed an association between osteoporosis and renal stones. The current analyses intended to investigate the bidirectional relationship between osteoporosis and renal stones. The ≥40-year-old population in the National Health Insurance Service-Health Screening cohort (2002-2015) was analyzed. In study I, 67,811 patients with osteoporosis and 67,811 control I participants were matched. The hazard ratio (HR) of osteoporosis for renal stones was calculated using stratified Cox proportional hazard models. In study II, 25,261 patients with renal stones and 101,044 control II participants were matched. The HR of renal stones for osteoporosis was estimated using stratified Cox proportional hazard models. In study I, 3.4% (2276/67,811) of osteoporosis patients and 2.5% (1696/67,811) of control I participants had renal stones. Osteoporosis patients had a 1.36 times higher HR for renal stones than control I participants (95% confidence intervals [CI] = 1.28-1.45). In study II, 9.2% (2319/25,261) of renal stone patients and 7.6% (7658/101,044) of control II participants had osteoporosis. Renal stone patients had a 1.26 times higher HR for osteoporosis than control II participants (95% CI = 1.21-1.32). Adults with osteoporosis had a higher risk of renal stones. Moreover, adults with renal stones had a higher risk of osteoporosis.

Predictors of Bone Mineral Density in Kidney Stone Formers

Introduction

Nephrolithiasis is associated with an increased fracture risk, but predictors of bone mineral density (BMD) in stone formers (SFs) remain poorly defined.

Methods

We conducted a retrospective analysis in the Bern Kidney Stone Registry (BKSR), an observational cohort of kidney SFs. Inclusion criteria were age ≥18 years and ≥1 past stone episode. Participants with non–calcium (Ca)-containing kidney stones, a history of primary hyperparathyroidism or antiresorptive or anabolic bone treatment were excluded. Multivariable linear regression analyses were used to assess the association of blood and 24-hours urine parameters and stone composition with BMD at the lumbar spine and femoral neck.

Results

In the analysis, 504 participants were included, mean age was 46 years, and 76% were male. In multivariable analyses, fasting (β: −0.031; P = 0.042), postload (β: −0.059; P = 0.0028) and Δ postload − fasting (β: −0.053; P = 0.0029) urine Ca-to-creatinine ratios after 1 week of a sodium- and Ca- restricted diet and Ca oxalate dihydrate stone content (β: −0.042; P = 0.011) were negatively associated with z scores at the lumbar spine. At the femoral neck, alkaline phosphatase (β: −0.035; P = 0.0034) and parathyroid hormone (PTH) (β: −0.035; P = 0.0026) were negatively associated with z scores, whereas 24-hours urine Ca (β: 0.033; P = 0.0085), magnesium (β: 0.043; P = 3.5 × 10⁻⁴), and potassium (β: 0.032; P = 0.012) correlated positively with z scores at the femoral neck.

Conclusion

Our study reveals distinct predictors of BMD in SFs. Commonly available clinical parameters, such as kidney stone composition results, can be used to identify SFs at risk for low BMD.

Bisphosphonates and management of kidney stones and bone disease

PURPOSE OF REVIEW

Kidney stones are strongly associated with low bone density and bone fracture. Clinical management focuses on prevention of kidney stones and bone fracture. We reviewed literature of kidney stones and bone disease with a special focus on updates in therapeutic strategies. We will review the literature regarding dietary management, supplements, and medications and emphasize the recent studies on bisphosphonates and kidney stone management.

RECENT FINDINGS

Bisphosphonate medications are commonly used in management of low bone density. Previous studies showed that they reduce urinary calcium. A recent large prospective study found that bisphosphonates may reduce the risk of kidney stones in individuals who have low bone density. In addition to lowering urinary calcium, a recent study found that bisphosphonates may act as an inhibitor in the urinary space.

SUMMARY

There are multiple dietary and pharmacologic strategies that can be considered for kidney stones and bone disease, such as low salt and normal calcium diet, as well as thiazides, alkali, and bisphosphonate medications. Bisphosphonates may have an important role in reducing bone resorption and reducing overall risk of kidney stone and bone disease.

Oxalobacter formigenes reduce the risk of kidney stones in patients exposed to oral antibiotics: a case-control study

This is the first prospective study to investigate the association between kidney stones, bone mineral density, serum testosterone, colon cancer and O. formigenes colonization. 40 kidney stone patients and 85 controls were enrolled. O. formigenes colonization was established. BMD was examined from T- and Z-scores using dual energy absorptiometry. O. formigenes was found in 28 of 40 cases and 80 of 85 controls. BMD was significantly reduced in patients (p < 0.05). The evaluation revealed a significant association between lowered O. formigenes colonization and low testosterone. Urinary calcium and oxalates levels were greater in patient. Serum testosterone and urinary citrate concentrations was reduced in patients with a significant difference. Also an association between O. formigenes and colon cancer was noted. Absence of O. formigenes might stand for a pathogenic factor in calcium oxalate stone, low bone mineral density, low testosterone levels and also colon cancer, when antibiotics are prescribed generously.

Urolithiasis increases the risk of subsequent onset of osteoporosis

Urolithiasis and osteoporosis are two different pathological entities, but are both important public health issues in older patients. Moreover, the two diseases may share some similar pathogenesis pathway. Currently, few studies focus on the relationship between urolithiasis and osteoporosis. Furthermore, whether the common mobilities influence the long-term osteoporosis rate in urolithiasis patients has never been studied. In the present study, we used the Taiwan National Health Insurance Database (LHID 2000) compiled by the NHI from 1996 to 2013 to determine whether urolithiasis influenced long-term osteoporosis; controls were matched for age, sex, and other comorbidities (including hypertension, diabetes mellitus, dyslipidemia, liver disease, and cardiovascular disease). We included a total of 91,254 patients, including 22,575 patients with urolithiasis and 68,679 control patients. There was a significant difference between the incidence of osteoporosis between the urolithiasis and control groups (adjusted hazard ratio 1.34, 95% CI 1.19-1.79, p < 0.001) during the follow up. The incidence rate of osteoporosis during the follow-up period was 8.87 per 1000 person-years in the urolithiasis group and 6.37 per 1000 person-years in the control group. Based on our results, it is evident that urolithiasis significantly increases the subsequent osteoporosis rate. Though the clinical mechanisms are not fully understood, patients who have a history of urolithiasis may need regular follow-up assessment of bone marrow density.

Vitamin D metabolism in dogs with and without hypercalciuric calcium oxalate urolithiasis

Background

There are abnormalities in vitamin D metabolism in people with calcium nephrolithiasis, but limited data are available on vitamin D status in dogs with calcium oxalate (CaOx) urolithiasis.

Objective

To compare serum concentrations of vitamin D metabolites in dogs with and without hypercalciuric CaOx urolithiasis.

Animals

Thirty‐eight dogs with (n = 19) and without (n = 19) a history of CaOx urolithiasis and hypercalciuria.

Methods

Retrospective cross‐sectional study. Serum 25‐hydroxyvitamin D [25(OH)D], 1,25‐dihydroxyvitamin D [1,25(OH)₂D], and 24,25‐dihydroxyvitamin D [24,25(OH)₂D] were measured. The ratios of 25(OH)D/24,25(OH)₂D and 1,25(OH)₂D/25(OH)D were compared between cases and controls.

Results

There were no significant differences between cases and controls when comparing 25(OH)D, 24,25(OH)₂D, 1,25(OH)₂D, or 1,25(OH)₂D/25(OH)D. Cases had higher 25(OH)D/24,25(OH)₂D (median = 1.40, range = 0.98‐1.58) compared to controls (median = 1.16, range = 0.92‐2.75; P = .01). There was overlap in the ranges for 25(OH)D/24,25(OH)₂D between cases and controls, but 6 cases (32%) had ratios above the control dog range. There was a moderate positive correlation between the ratio of 25(OH)D/24,25(OH)₂D and urinary calcium‐to‐creatinine ratios (r = 0.40, 95% confidence interval = 0.10‐0.64; P = .01).

Conclusions and Clinical Importance

These data suggest that decreased conversion of 25(OH)D to 24,25(OH)₂D occurs in a subset of dogs with CaOx urolithiasis. Abnormalities in vitamin D metabolism might contribute to stone risk in dogs.

Bone resorption in dogs with calcium oxalate urolithiasis and idiopathic hypercalciuria

People with calcium oxalate (CaOx) urolithiasis and idiopathic hypercalciuria (IH) often have evidence of increased bone resorption, but bone turnover has not previously been investigated in dogs with these conditions. The aim of this study was to determine whether a marker of bone resorption, β-crosslaps, differs between dogs with CaOx urolithiasis and IH compared to controls. This retrospective, cross-sectional study used a canine specific ELISA to measure β-crosslaps concentrations in stored frozen serum samples from 20 dogs with CaOx urolithiasis and IH and 20 breed-, sex-, and age-matched stone-free controls (18 Miniature Schnauzers, 14 Bichons Frise, and 8 Shih Tzus). Dogs with CaOx urolithiasis and IH had lower β-crosslaps concentrations relative to controls (P = .0043), and β-crosslaps had a moderate negative correlation with urinary calcium-to-creatinine ratios (r = -0.44, P = .0044). Miniature Schnauzers had lower β-crosslaps concentrations than the other two breeds (P = .0035). The ELISA had acceptable intra-assay precision, but concentrations decreased when samples were repeatedly assayed over time. Assay recovery rates were also below acceptance criteria. In conclusion, Miniature Schnauzers, Bichons Frise, and Shih Tzus with CaOx urolithiasis and IH have evidence of decreased bone resorption compared to stone-free controls. This suggests that other causes of IH, such as intestinal hyperabsorption of calcium, underlie risk for CaOx urolithiasis in these breeds. Results should be confirmed in larger populations and with other β-crosslaps assays and additional biomarkers of bone turnover. The stability of canine serum β-crosslaps after freeze-thaw cycles and storage at various temperatures requires investigation.

Risk of renal stone formation in patients treated with luteinising hormone-releasing hormone analogues for prostate cancer: importance of bone metabolism and urine calcium

PURPOSE

To determine whether androgen blockade produces metabolic changes in urine and increases the risk of calculi after 1 year of treatment.

MATERIALS AND METHODS

The study included 38 patients, from the period April 2015 to June 2016, diagnosed with locally advanced prostate cancer or lymph node metastasis, and with an indication of androgen blockade. Androgen blockade was started with luteinising hormone-releasing hormone (LHRH) analogues, and a blood specimen, a fasting urine and 24-h urine were collected at the time of inclusion, and then at 1 year of follow-up. A study was performed at baseline and at 1 year with imaging tests. An analysis of the variables was performed with a p ≤ 0.05 considered as statistically significant.

RESULTS

The mean age of the patients included in the study was 72.26 ± 6.75 years. As regards the biochemistry parameters, an increase in osteocalcin (from 16.28 ± 9.48 to 25.56 ± 12.09 ng/ml; p = 0.001) and an increase in β-crosslaps (from 0.419 ± 0.177 to 0.743 ± 0.268 ng/ml; p = 0.0001) were observed. In the urinary parameters, a significant increase was observed in the fasting calcium/creatinine ratio (from 0.08 ± 0.06 to 0.13 ± 0.06; p = 0.002) and in the 24-h calcium renal excretion (from 117.69 ± 66.92 to 169.42 ± 107.18 mg; p = 0.0001). Calculi formation was observed in 12 of the 38 patients included (31.6%), with a mean size of 3.33 ± 1.31 mm.

CONCLUSION

Treatment with LHRH analogues, as well as increasing the appearance of metabolic syndrome and speeding up the loss bone mineral density, causes an increase in fasting urine calcium.

Bone-associated gene evolution and the origin of flight in birds

BACKGROUND

Bones have been subjected to considerable selective pressure throughout vertebrate evolution, such as occurred during the adaptations associated with the development of powered flight. Powered flight evolved independently in two extant clades of vertebrates, birds and bats. While this trait provided advantages such as in aerial foraging habits, escape from predators or long-distance travels, it also imposed great challenges, namely in the bone structure.

RESULTS

We performed comparative genomic analyses of 89 bone-associated genes from 47 avian genomes (including 45 new), 39 mammalian, and 20 reptilian genomes, and demonstrate that birds, after correcting for multiple testing, have an almost two-fold increase in the number of bone-associated genes with evidence of positive selection (~52.8 %) compared with mammals (~30.3 %). Most of the positive-selected genes in birds are linked with bone regulation and remodeling and thirteen have been linked with functional pathways relevant to powered flight, including bone metabolism, bone fusion, muscle development and hyperglycemia levels. Genes encoding proteins involved in bone resorption, such as TPP1, had a high number of sites under Darwinian selection in birds.

CONCLUSIONS

Patterns of positive selection observed in bird ossification genes suggest that there was a period of intense selective pressure to improve flight efficiency that was closely linked with constraints on body size.

Correlation of Osteoporosis and Calcium Urolithiasis in Adult Population

Introduction:

Scientific studies indicate that there is a correlation between decreased bone mineral density and the age of the patient, especially in post menopausal women.

Goal:

The aim of our study was to assess the connection between osteoporosis and the age of respondents, based on the DEXA findings in patients with calcium urolithiasis.

Material and methods:

The study was prospectively and conducted in University Clinical Center Banja Luka, at the Urology Clinic and Clinic of Internal Medicine. In this study the respondents were divided into two groups: experimental group–subjects with calcium urolithiasis and control group without calcium urolithiasis. The study included 240 patients, in both groups of 120 patients who were divided into three age groups: 20-40 years, 40-60 years and more than 60 years. In both groups of respondents was conducted determination of bone mineral density in L2-L4 vertebra lumbar spine and hip by DEXA method.

Results:

Observing the whole sample of the experimental group, according to age groups it can be noticed that DEXA results are at 72.5% normal, 27.5% below expected value, more in women within older subgroups, 20% show signs of osteopenia and osteoporosis in 7.5 %. Share of patients with osteoporosis is statistically different (p<0.05) only between sub-groups 20-40 years and over 60 years. Although appears absolute difference in the participation of patients with osteopenia by age groups, the differences are not statistically significant (p>0.05). The share of patients with normal DEXA values was significantly lower in the group over 60 years compared to the other two age groups (p<0.05). At age subgroups of the control group, the youngest group of respondents share with normal DEXA finding is 95% and among the oldest group (over 60 years) this share is much lower and is 60%, which represents a statistically significant difference, and confirms the relationship (p<0.01). Normal DEXA findings decreases with increasing years, the share of those who do not have normal findings is higher in the elderly population.

Conclusion:

Our study has just shown that in adult patients with calcium urolithiasis osteoporosis is more prevalent in older patients and more pronounced in patients with calcium urolithiasis in relation to the population without the same.

Low Oxalobacter Formigenes Colonization is Associated with Reduced Bone Mineral Density in Urinary Stone Forming Patients

Introduction

Lower bone mineral density (BMD) and reduced Oxalobacter formigenes colonization are common findings in urolithiasis patients. But none of the studies conducted investigated the relationship between decreased bone mineral density and reduced Oxalobacter colonization. Here we evaluated the relation between BMD and O. formigenes colonization in urolithiasis patients.

Materials and Methods

50 stone formers (48.9 ± 11.9 years) and 50 control (47.2 ± 13.4 years) adult male subjects were included in the study. Alterations in O. formigenes colonization were determined as absolute O. formigenes count from fecal samples by real time polymerase chain reaction using species specific primers. BMD was evaluated from t- and z- scores calculated by using dual energy absorptiometry in the total femoral neck and lumbar spine (L2-L4).

Results

Low BMD was observed in 18 (36%) urinary stone forming patients and in 7 (14%) control subjects in the lumbar area (p < 0.05). The mean O. formigenes count in stone formers and control subjects were 19,257 (5,791 ± 1,117.93) and 143,850 (2,815,725 ± 3,946,044.7) (p < 0.05) respectively. We observed a correlation between decreased lumbar BMD and O. formigenes colonization and testosterone levels in stone formers. Our results indicated that diminished O. formigenes colonization in the gut of urinary stone forming subjects was associated with reduced BMD.

Gender Representation of Osteoporosis in Patients with Urolithiasis

Introduction:

A great number of clinical studies has indicated that the patients with calcium urolithiasis have a reduced mineral bone density.

Aim:

The aim of our research was to establish representation of osteoporosis, by measuring mineral bone density using the DEXA method, in patients with calcium urolithiasis, by gender.

Material and methods:

The research was a prospective one, performed at the University Hospital of the Clinical Center of Banja Luka, at the Urology Clinic and Clinic for Endocrinology, Diabetes and Metabolic Diseases. The material in this research were the patients divided into two groups: a working group (the patients suffering from calcium urolithiasis) and a control group (the patients without calcium urolithiasis). One hundred and twenty (120) patients were included in both these groups, divided in three age subgroups: 20-40, 40-60 and over 60. The total working group consisted of 63 men (52.2%) and 57 (47.5%) women. In the control group, the number of women was 72 (60%) and 48 (40%) of men. Establishing of mineral bone density at L2-L4 of lumbal spine vertebrae and hip was done for the patients in both these groups, using DEXA method.

Results:

Analysis of mineral bone density using DEXA method in patients by gender of working and control groups has shown that osteoporosis and osteopenia in patients of the working group is significantly more present in women (14% and 22.8%) compared to men (1.6% and 17.5%). When compared by gender in the control group, osteoporosis was present a lot more in women (36.1%) compared to men (2.1%). When observed for the total sample of both the working and control group, there was a statistically significant difference (p<0,01) related to gender structure, where the share of women with osteoporosis/osteopenia was significantly higher (36.1%) compared to men (4.2%).

Conclusion:

Representation of osteoporosis in women with urolithiasis, particularly of older age, is very expressed and this is why prevention measures should start as soon as possible, so as to avoid severe complications of this illness.

The importance of urinary calcium in postmenopausal women with osteoporotic fracture

INTRODUCTION

Calcium stones are associated with osteoporosis and manifested mainly by elevated fasting urinary calcium/creatinine ratio. The objective of this study is to demonstrate the presence of abnormal metabolism of calcium and calciuria in women with osteoporotic fracture with no previously known renal lithiasis compared to women without osteoporosis and without renal lithiasis.

METHODS

In total, 87 women were included in the study. They were divided into two groups: Group 1 with 55 postmenopausal women with osteoporotic fracture and without renal lithiasis; and Group 2 with 32 postmenopausal women without osteoporosis and without history of renal lithiasis. The following parameters of phospho-calcium metabolism were analyzed: calciuria 24-hour, oxaluria 24-hour, uricosuria 24-hour, and citraturia 24-hour. The presence of hypercalciuria, hyperoxaluria, hyperuricosuria, and hypocitraturia was compared between groups. Statistical significance was set at p ≤ 0.05.

RESULTS

The mean age was 70.1 ± 13.8 in Group 1 and 56.7 ± 6.4 in Group 2 (p = 0.0001). Women in Group 1 had higher levels of serum alkaline phosphatase (p < 0.05) and fasting urinary calcium/creatinine ratio (p < 0.05). The percentage of patients with hypercalciuria in Group 1 (40%) was higher compared to Group 2 (18.8%) and statistically significant (p = 0.04). There were no statistically significant differences in the percentage of hyperoxaluria, hyperuricosuria, and hypocitraturia between groups. This study has its limitations including its cross-sectional nature at a unique centre and its low number of patients.

CONCLUSION

The determination of urinary calcium and fasting calcium/creatinine ratio in postmenopausal women with osteoporotic fracture without renal lithiasis may facilitate individualization of medical therapy and decreasing lithogenic risk.

Calcium nephrolithiasis and bone demineralization: pathophysiology, diagnosis, and medical management

PURPOSE OF REVIEW

To establish the relationship between calcium nephrolithiasis, bone densitometry scoring, and bone mineral density (BMD) loss according to bone turnover markers (BTMs) and urinary metabolites.

RECENT FINDINGS

Patients with recurrent calcium nephrolithiasis and idiopathic fasting hypercalciuria (urinary calcium/creatinine ratio >0.11) are more likely to have BMD loss that may lead to osteopenia or osteoporosis. In these patients, BTMs may be used as a surrogate for both bone health and stone recurrence. Suspect higher lithogenic states when calcium stone formers have serum beta-crosslaps (resorptive marker) greater than 0.311 ng/ml, serum osteocalcin (formative marker) greater than 13.2 ng/ml, and beta-crosslaps/osteocalcin ratio greater than 0.024.

SUMMARY

Patients with recurrent calcium nephrolithiasis and fasting hypercalciuria have a higher incidence of osteopenia and osteoporosis, measured by the dual-energy X-ray absorptiometry. These patients present not only with hypercalciuria and increased BTMs (mainly resorptive), but also up to 30% have hypocitraturia and increased urinary calcium/citrate ratio (>0.25). On the basis of these results, a diagnostic algorithm was created, classifying hypercalciurics according to their fasting calcium/creatinine and calcium/citrate ratio. Medical therapy for these patients is aimed at improving the dietary habits (normocalcemic, low salt, low animal protein diet), prescribing combinations of potassium citrate, thiazides, and bisphosphonates, and correcting bone and urinary abnormalities that may lower future skeletal and kidney stone risk.

Calcium and phosphorus metabolism and lithogenic factors in patients with osteoporotic fracture

OBJECTIVES

To demonstrate the attendance of mineral metabolism disorders and lithogenic factors in patients' urine with osteoporotic fracture without previously known stones

MATERIAL AND METHODS

67 patients with osteoporotic fractures surgically treated in trauma service are included. The area of the fracture site, fracture mechanism and the presence of osteoporosis were the factors taken into account to diagnose osteoporotic fracture. Mineral metabolism, calciuria, oxaluria, uricosuria and citraturia in 24hours urine were analyzed. The presence of abnormal calcium and phosphorus metabolism was proved comparing hypercalciuria patients with normocalciuria ones.

RESULTS

12 men and 55 women with mean age 68.8±14.5 years old were included. Mean Body Mass Index (BMI) was 27.4±4.1kg/m2. 42% of patients showed hypercalciuria, 34% hyperoxaluria, 34% hypocitraturia and 7% hyperuricosuria. Statistically significant differences were observed only in fasting calcium/creatinine ratio (0.17 vs. 0.08; P<.0001) when comparing patients with hypercalciuria with those with normocalciuria.

CONCLUSIONS

Patients with osteoporotic fractures show different lithogenic factors in urine, mainly hypercalciuria, always in fasting conditions.

Retrospective review of serum and urinary lithogenic risk factors in patients with osteoporosis and osteopenia

OBJECTIVE

To analyze differences in bone remodeling markers, lithogenic factors and bone densitometry among the 3 groups of patients (controls, patients with relapsing calcium renal lithiasis, and patients with loss of bone mineral density without lithiasis).

MATERIAL AND METHODS

This is a cross-sectional study including 203 patients who were divided in 3 groups: group 1 (controls), group 2 (patients with relapsing calcium renal lithiasis), and group 3 (patients with osteopenia and/or osteoporosis in the lumbar spine or hip). Bone densitometry, calcium-phosphorous and bone metabolism analysis, and analysis of lithogenic risk factors in fasting urine samples and 24-hour urine samples were performed. Statistical analysis was performed with SPSS 17.0. A P ≤.05 was considered statistically significant.

RESULTS

Patients in group 2 presented greater calcium excretion and a lower citrate excretion in 24-hour urine samples as compared with the other 2 groups. The proportion of hypercalciuria and hypocitraturia was higher in group 2. In addition, patients in group 2 presented a lower loss of bone mineral density as well as altered bone remodeling markers as compared with those in group 1. Patients in group 3 also presented alterations in urine calcium and citrate excretion with respect to the control group, with elevated fasting calcium and citrate levels and calcium-to-citrateratio.

CONCLUSION

Lithogenic risk factors are altered in patients with osteopenia and/or osteoporosis without renal lithiasis although to a lesser extent than patients with calcium renal lithiasis.

The importance of calciuria as lithogenic factors in patients with osteopenia/osteoporosis

PURPOSE

Recurrent kidney stones are associated with bone mineral density loss, altered bone remodeling markers, hypercalciuria and increased in fasting calcium/creatinine ratio. The objective was to determine biochemical alterations in urine in patients with osteopenia/osteoporosis without calcium kidney stones compared with patients with calcium kidney stones.

METHODS

This is a cross-sectional study including 142 patients who were divided in two groups: Group 1 (patients with recurrent calcium kidney stones) and Group 2 (patients with osteopenia/osteoporosis in the lumbar spine or hip). Analyses of bone mineral density, calcium-phosphorous and bone metabolism and lithogenic risk factors in fasting urine samples and 24-h urine samples were performed. Statistical analysis was carried out with SPSS 17.0. A p ≤ 0.05 was considered statistically significant.

RESULTS

Patients in Group 2 presented greater loss of bone mineral density and more elevated alkaline phosphatase, iPTH, phosphorous and β-crosslaps levels, as compared to patients in Group 1. However, Group 1 presented greater urine calcium, oxalate and uric acid and a higher proportion of hypocitraturia, hypercalciuria and hyperoxaluria, as compared to Group 2. Multivariate analysis revealed that advanced age and β-crosslaps levels are risk factors for bone mineral density loss, while low urinary calcium excretion was protective against bone demineralization.

CONCLUSION

Patients with osteopenia/osteoporosis without lithiasis present some urinary biochemical alterations. This would explain the lack of lithogenic activity, although low calcium excretion in 24-h urine samples is a protective factor against the loss of bone mineral density.

Incidence of osteoporosis in patients with urolithiasis

Introduction.

Clinical researches have shown an increased bone disintegration and lower bone mass in patients with calcium urolithiasis.

Goal.

The goal of our research was to establish the incidence of osteoporosis in adult patients with calcium urolithiasis, on the basis of measuring mineral bone density, using DEXA method, with a special reflection on age subgroups.

Material and methods.

Clinical research was prospective and it was implemented at the University Clinical Center of Banja Luka, at the Clinic for Endocrinology, Diabetes and Metabolic Diseases and at the Urology Clinic. Material in this research consisted of patients divided in two groups, a working and a control group. One hundred and twenty (120) patients were included in both these groups, divided in three age subgroups: 20-40, 40-60 and over 60. The working group consisted of the patients with calcium urolithiasis and the control group consisted of patients without calcium urolithiasis. Establishing of mineral bone density at L2-L4 of lumbal spine vertebrae and hip was done for the patients in both these groups, using DEXA method.

Results.

Analysis of mineral bone density using DEXA method in patients in age groups of working and control groups, as well as in the total sample of working and control groups, have shown that the patients of the working group, over 60, had a decreased mineral bone density (30% of osteopenia and 15% osteoporosis) significantly more expressed when compared to the other two age groups (12.5% in the subgroup 20-40 and 17.5% in the subgroup 40-60), which presents a statistically significant difference (p<0.05). In the control group, when taking into account age groups, osteopenia and osteoporosis were marked in 37.5% and 2.5% in the group of patients over 60, whereas in the youngest population, 5% of osteopenia was found, which presents a statistically significant difference (p<0.05). When observing the total sample of working and control group, there was a statistically significant difference in the working and control group (p<0.01); incidence of osteoporosis in the working group amounted to 7.5% and in the control group it was 0.8%.

Conclusion.

Urolithiasis and osteoporosis are two multifactorial diseases which are evidently reciprocal. This is why we suggest that educating the population about the risk factors for occurrence of these diseases as well as preventive measures that may contribute to their decrease should begin as early as possible.

Osteoporosis and the risk of symptomatic nephrolithiasis: a population-based 5-year follow-up study in Taiwan

This study estimates the risk of symptomatic nephrolithiasis within 5 years of newly diagnosed osteoporosis in a Taiwan population. This cohort study consisted of patients with a diagnosis of osteoporosis between Jan. 2003 and Dec. 2005 (N = 1634). Four age- and gender- matched patients for every patient in the study cohort were selected using random sampling as the comparison cohort (N = 6536). All patients were tracked for 5 years from the date of cohort entry to identify whether they developed symptomatic nephrolithiasis. Cox proportional hazard regressions were performed to evaluate the 5-year nephrolithiasis-free survival rates. During the 5-year follow-up period, 60 osteoporosis patients (3.7%) and 165 non- osteoporosis patients (2.5%) developed symptomatic nephrolithiasis. The adjusted HR of symptomatic nephrolithiasis was 1.38 times greater risk for patients with osteoporosis than for the comparison cohort (95% confidence interval (CI) 1.03-1.86; P < .05). Osteoporosis is very likely to be an independent risk factor for subsequent diagnosis of symptomatic nephrolithiasis.

Calcium renal lithiasis and bone mineral density. Importance of bone metabolism in urinary lithiasis

CONTEXT

Calcium Nephrolithiasis is a multifactorial disease; in its pathophysiology is involved various minerals and metabolic factors that may be altered, including bone and phosphor-calcium metabolism.

OBJECTIVE

To establish the scientific evidence and demonstrate the relationship between calcium nephrolithiasis and bone mineral density loss, through the use of bone turnover markers, serum and urinary metabolites.

EVIDENCE ACQUISITION

We performed a PubMed literature review using different MeSH Terms like "Nephrolithiasis", "Bone mineral density", "Urinary stones", "Calcium", Bone resorption" and "Bone formation", with different combinations. We only selected articles with abstracts in English or Spanish and discarded clinical cases and articles with inappropriate statistical study. A total of 40 articles were selected.

EVIDENCE SYNTHESIS

In different studies reviewed have been observed that patients with hypercalciuria have a higher bone mineral density loss with respect to normocalciuric. Among patients with calcium stones (normocalciuric or hypercalciuric), there is loss of bone mineral density, being more evident in patients with stones and hypercalciuria. This mineral density loss is marked and important in patients with recurrent calcium stones. Increased markers like fasting calcium/creatinine and β-CrossLaps are determinant of nephrolithiasis and mineral density loss in these patients.

CONCLUSION

We recommend perform markers of bone turnover and fasting calcium/creatinine in patients with recurrent calcium stones by the significant presence of bone mineral density loss, with a level of evidence III.

Association of severe calcium lithogenic activity and bone remodeling markers

OBJECTIVE

To establish cutoff points for markers of bone remodeling that allow for screening of patients at risk for serious lithogenic activity.

MATERIALS AND METHODS

We conducted a cross-sectional study with 182 patients (aged between 25 and 60 years) divided into 3 groups: group 1, 56 patients without lithiasis; group 2, 67 patients with light calcium lithiasis; and group 3, 59 patients with severe calcium lithiasis. The criteria for inclusion in and exclusion from the study were established, and light and severe lithogenic activity were defined. Metabolic variables in blood and urine, along with bone densitometry, were studied for the groups. Statistical analysis of the results and preparation of receiver operating characteristic curves to establish optimal cutoff points were performed.

RESULTS

The patients in group 3 showed the greatest bone mineral density loss and the highest values for markers of bone remodeling, together with increased 24-hour calciuria. Using the receiver operating characteristic curves developed and based on statistical significance (P = .0001), the following cutoff points for severe lithogenic activity, with a sensitivity between 75% and 85%, were established: β-crosslaps >0.331 ng/mL; osteocalcin >13.2 ng/mL; β-crosslaps/osteocalcin >0.024; 24-hour calciuria >306.6 mg; and fasting urine calcium/creatinine >0.105.

CONCLUSION

Patients with calcium lithiasis and elevated values for osteocalcin, β-crosslaps, β-crosslaps/osteocalcin, 24-hour calciuria, and fasting urine calcium/creatinine may present a high risk of severe lithogenic activity.

Association of bone mineral density with incidental renal stone in long-term survivors of childhood acute lymphoblastic leukemia

PURPOSE

Our objective was to evaluate the association between low bone mineral density (BMD) and incidental renal stones among long-term survivors of childhood acute lymphoblastic leukemia (ALL).

METHODS

Adult participants who were 10+ years from their childhood ALL diagnosis and members of the St. Jude Lifetime Cohort study were recruited between December 2007 and March 2011. During their risk-based medical evaluations, they underwent quantitative computed tomography (QCT) to evaluate BMD. Incidental renal stones were identified by radiologists' review of axial QCT source images. Demographic and dietary information were abstracted from health surveys and the Block Food Frequency questionnaire, respectively. The multivariable logistic regression model was used for analysis.

RESULTS

At a median of 26.1 years from diagnosis, BMD Z scores were ≤-2 in 34 of 662 (5.2 %) and renal stones detected in 73 of 662 (11 %) participants. Adjusted for age, renal radiation, dietary vitamin D, gender, and body mass index, when compared to those with BMD Z scores ≥0, the risk of renal stones was increased among those with BMD Z scores ≤-2 (odds ratio [OR], 2.92; 95 % confidence interval [CI] 1.14-7.48). Risk of renal stones significantly increased for older age (45-54 vs.18-24 years; OR, 3.70; 95 % CI 1.11-12.35) whereas the risk was higher but nonsignificant for >141.5 IU (sample median) daily intake of vitamin D (OR, 1.64; 95 % CI 0.98-2.75).

CONCLUSIONS AND IMPLICATIONS FOR CANCER SURVIVORS

Older ALL survivors with BMD Z scores ≤-2 are at risk for renal stones and should be counseled so that appropriate follow-up care can be provided for those among whom renal stones are detected.

Biochemical determinants of severe lithogenic activity in patients with idiopathic calcium nephrolithiasis

OBJECTIVE

To analyze the biochemical alterations in plasma and the urine determinants of severe lithogenic activity in patients with idiopathic calcium nephrolithiasis.

METHODS

We performed a cross-sectional study of 120 patients divided into 2 groups: group 1, 60 patients without nephrolithiasis; and group 2, 60 patients with severe and/or recurrent calcium nephrolithiasis. In all patients, a study of renal function, calcium metabolism, and bone remodeling markers, and a study of the lithogenic factors were performed in urine after fasting and in 24-hour urine samples.

RESULTS

We observed greater values for phosphorus in group 1 than in group 2 (P=.03). Also, we found greater values for intact parathyroid hormone (P=.01), osteocalcin (P=.000), and β-crosslaps (P=.000) in group 2 than in group 1. In the 24-hour urine samples, significant differences were found between groups 1 and 2 in calciuria (11.7 vs 17.4 mg/dL; P=.000), citraturia (50.6 vs 33.5 mg/dL; P=.002), calcium/creatinine quotient (0.14 vs 0.20; P=.001), calcium/citrate quotient (0.05 vs 0.13; P=.04), and calcium/creatinine quotient after fasting (0.09 vs 0.16; P=.000).

CONCLUSION

We consider the determinants of severe and/or recurrent calcium lithiasis to be hypercalciuria and hypocitraturia and a calcium/citrate quotient>0.06. As risk markers we can consider phosphatemia<2.9 mg/dL, phosphate/chlorine quotient>35, alkaline phosphatase>80 U/L, intact parathyroid hormone>60 pg/mL, osteocalcin>16 ng/mL, β-crosslaps>0.400 ng/mL, and β-crosslaps/osteocalcin quotient>0.028.