Urinary Calcium Concentrations Research Articles

Upper urolithiasis in cats with chronic kidney disease: prevalence and investigation of serum and urinary calcium concentrations.

This study aimed to define the prevalence of upper urolithiasis in cats with chronic kidney disease (CKD) in a referral population, and to compare urinary calcium:creatinine ratio (UCa:Cr), and total and ionised calcium between cats with CKD with and without upper urolithiasis. The medical records of cats diagnosed with CKD were reviewed for signalment, body weight, diet and prevalence of upper urolithiasis. Cats with preserved urine samples were further classified into two groups: urolithiasis group (upper urolithiasis identified by abdominal ultrasonography) and control group (CKD of unknown origin). Serum biochemical analysis, CKD stage, blood gas analysis, urine specific gravity and UCa:Cr were compared between groups using a two-sample t-test or Mann-Whitney U-test for continuous variable and a χ2 test or Fisher's exact test for categorical variables. Multivariable binary logistic regression analysis was used to identify risk factors. Among the 140 cats with CKD, the prevalence of upper urolithiasis was 73%. Fifty cats (5, 29 and 16 cats with CKD stages 1, 2 and 3, respectively) with urine samples met the inclusion criteria and were included in the analysis. Among cats with CKD, being purebred (odds ratio [OR] = 81.56; P = 0.03) and being fed dry food only (OR = 25.06; P = 0.001) were identified as independent upper urolithiasis risk factors; those with upper urolithiasis were more likely to be exclusively fed with urine-acidifying food (P <0.001) and have increased serum ionised calcium (iCa) (P = 0.044), fractional excretion of calcium (P = 0.45) and UCa:Cr (P = 0.005) than cats with CKD without upper urolithiasis. Cats with CKD that were purebred, fed dry food and fed urine-acidifying food only often had upper urolithiasis. A higher UCa:Cr may be a result of increased serum iCa and may cause upper urolithiasis.

Multicenter retro-prospective observational study on chronic hypoparathyroidism and rhPTH (1–84) treatment

PurposeThe main purpose of this study was to investigate the effects of 12 months of rhPTH (1–84) (Natpar®) treatment in a cohort of patients selected according to the indications of hypoparathyroidism guidelines. The use of recombinant human PTH (1–84) [rhPTH (1–84)] is approved as hormonal replacement therapy in patients with hypoparathyroidism not adequately controlled with conventional therapy.MethodsIt is a multicenter, observational, retro-prospective, open label study. Eleven Italian Endocrinological centers, members of Hypoparathyroidism Working Group of the Italian Society of Endocrinology (HypoparaNET) were involved. Main outcome measures were serum and urinary calcium and phosphate concentration, calcium-phosphate product, renal function, oral calcium and vitamin D doses, and clinical manifestations.ResultsFourteen adult subjects, affected by chronic hypoparathyroidism, were treated with rhPTH (1–84) for 12 months. At 12 months of rhPTH (1–84) treatment, 61.5% of patients discontinued calcium supplement and 69.2% calcitriol. Mean albumin-adjusted total serum calcium levels quickly normalized after initiation of rhPTH (1–84) treatment compared to baseline (p = 0.009), remaining in the normal range until 12 months. Rare hypo-hypercalcemia episodes were reported. Renal function was maintained normal and no renal complications were reported. Serum and urinary phosphate and urinary calcium were maintained in the normal range. Mean phosphatemia levels linearly decreased from 3 months up to 12 months compared to baseline (p = 0.014). No severe adverse events were described.ConclusionsBiochemical and clinical results confirm the efficacy and safety of rhPTH (1–84) therapy, which represents an important option for hypoparathyroid patients unresponsive to conventional therapy.

Urine uromodulin and angiotensin converting enzyme inhibitors: is there a relationship?

BACKGROUND. Uromodulin (UMO) is a multifunctional glycoprotein expressed in epithelial cells of the thick ascending part of the loop of Henle. Currently, enough information has been accumulated about the participation of this glycoprotein in a number of important physiological and pathological processes. THE AIM: to evaluate the relationship between the level of urine uromodulin (Umo) and the intake of angiotensin converting enzyme (ACE) inhibitors in chronic kidney disease. PATIENTS AND METHODS. 96 patients aged 43.6±15.4 years were examined. (M:W = 46:50). The presence of kidney disease in all cases is confirmed morphologically. The main criterion for the inclusion of patients in the study was the presence of CKD C1-C3. The exclusion criteria were age over 70 years, the presence of diabetes mellitus, immunosuppressive therapy at the time of examination, taking diuretics. Umo concentrations in blood serum (SUmo) and urine (UUmo) were measured by enzyme immunoassay. Serum and urinary concentrations of creatinine, potassium, sodium, chlorine, calcium, and inorganic phosphorus, as well as protein levels in urine, were also determined. The glomerular filtration rate (eGFR) was calculated using the formula CKD-EPI. The values of daily excretion, clearance, and fractional excretion were calculated for all ions. RESULTS. The patients were divided into two groups: group 1 – 20 people who did not take ACE inhibitors; group 2 – 78 people who took ACE inhibitors. The content of Umo in urine correlated in the first group with the value of systolic and diastolic blood pressure and serum Umo. In the second group, associations of the concentration of Umo in urine with age, eGFR, the excreted fraction of sodium and chlorine, and serum Umo were noted. CONCLUSION. The data obtained suggest that the nephroprotective properties of ACE inhibitors are broader than is commonly thought. Our data allow us to talk about their protective effect at the level of the tubular apparatus. The authors believe that the information currently available is quite sufficient to discuss the need to introduce the definitions of SUmo and UUmo into real clinical practice.

Effects of vitamin D with or without calcium on pathological ossification: A retrospective clinical study.

Vitamin D protects against the development and severity of several rheumatic diseases. However, the effect of vitamin D on the pathological ossification associated with rheumatic diseases remains unknown. The present retrospective study analyzed the clinical outcomes of vitamin D without calcium compared with vitamin D with calcium on pathological ossification in joints and ligaments. Data were collected from patients who were diagnosed with osteoarthritis, rheumatoid arthritis or spondylarthritis, and the presence of pathological ossification in joints or ligaments was confirmed by X-ray, computed tomography or magnetic resonance imaging examination. A total of 2,965 patients aged 18-75 years old were included, among who, 1,725 were included in the vitamin D alone group and 1,240 in the vitamin D with calcium group. Vitamin D was administered intramuscularly (300,000 IU) once every 7-10 days, 4-6 times in total. Patients who ingested an oral calcium supplement (1,000 mg/day; ≥5 days/week) were considered the vitamin D with calcium group. The clinical outcome was evaluated based on the imaging changes of pathological ossification, which were classified as alleviation, aggravation and unchanged. The bone mineral density (BMD) was determined, and the calcium concentration in the serum and urine was measured. The results revealed that vitamin D alone alleviated pathological ossification, while vitamin D combined with calcium aggravated pathological ossification in the majority of patients (P<0.0001) independent of disease type and patient age. BMD measurements demonstrated a decreasing trend in the vitamin D alone group, whereas they exhibited an increasing trend in the vitamin D combined with calcium group. The urine calcium concentration increased after vitamin D treatment alone. Therefore, it was concluded that vitamin D exerted both pro-resorptive and anti-resorptive actions on pathological ossification. The bidirectional action of vitamin D on bone metabolism may depend on exogenous calcium supplementation.

Estimating 24-hour urinary excretion using spot urine measurements in kidney stone formers.

ABSTRACTBackgroundOne limitation of the use of 24-hour collection is impracticality. We analysed the performance of spot urine measurements to estimate 24-hour excretion in patients with kidney stones.MethodsA total of 74 adult patients from two centres performed a 24-hour urine collection. A sample of the last micturition was sent for spot urine analysis. Twenty patients were asked to collect two additional spot urine samples, one before dinner and the other after dinner. Urinary concentrations of creatinine, calcium, oxalate, uric acid, citrate and magnesium were measured in the 24-hour and each of the spot urine samples. Four approaches were used to estimate 24-hour urinary excretion, multiplying the ratio of the spot urinary analyte to creatinine concentration by (i) measured 24-hour urinary creatinine excretion (Prediction 1), (ii) estimated 24-hour urinary creatinine excretion (Prediction 2), (iii) assumed 1-g 24-hour urinary creatinine excretion (Prediction 3) or (iv) assumed 1.5-g 24-hour urinary creatinine excretion (Prediction 4). For each parameter we computed Lin's concordance correlation coefficients (CCCs), Bland–Altman plots and 95% limits of agreement.ResultsThe performance of estimates obtained with Prediction 1 and Prediction 2 was similar, except for citrate and uric acid, for which Prediction 2 performed worse. Both approaches performed moderately well: citrate CCC {0.82 [95% confidence interval (CI) 0.75–0.90]}, oxalate [0.66 (95% CI 0.55–0.78)], magnesium [0.66 (95% CI 0.54–0.77)], calcium [0.63 (95% CI 0.50–0.75)] and uric acid [0.52 (95% CI 0.36–0.68)]. The performance of Predictions 3 and 4 was worse.ConclusionsAlthough spot urine samples may hold promise for clinical and population-based research, at present they have limited utility in clinical practice. Measuring or estimating 24-hour creatinine, rather than assuming a given creatinine excretion, will be necessary in future studies of spot urine samples.

Protective Effects of Total Flavonoids from Lysimachia christinae on Calcium Oxalate-Induced Oxidative Stress in a Renal Cell Line and Renal Tissue.

Oxidative stress (OS) in renal tubular epithelial cells (RTECs) is induced by calcium oxalate (CaOx) stones and plays an important role in the pathology of CaOx nephrolithiasis. The nuclear factor-E2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway is an important endogenous antioxidant pathway. Flavonoids are compounds with 2-phenylchromone as the basic mother nucleus and are natural antioxidant components of Lysimachia christinae. Our previous studies demonstrated that the total flavonoids from L. christinae (TFL) reduced calcium and oxalic acid concentrations in urine, thus inhibiting CaOx stone formation. We also showed that TFL can reduce OS in renal tissue. However, whether TFL inhibit the formation of CaOx stones through the Nrf2/ARE pathway requires further investigation. Here, we found that TFL protected against injury to a renal cell line and renal tissue, reduced CaOx-induced OS in renal tissue, and reduced CaOx crystal formation. In addition, TFL significantly increased nuclear Nrf2 and the expression of the downstream antioxidant genes heme oxygenase 1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO-1). Furthermore, TFL increased superoxide dismutase (SOD) activity and decreased the malondialdehyde (MDA) content, thereby alleviating OS in RTECs. Silencing Nrf2 expression blocked the protective effect of TFL on CaOx-induced OS. Taken together, our findings indicate that TFL reduce CaOx-induced OS in renal tissue by activating the Nrf2/ARE pathway.

Increased Water Viscosity Enhances Water Intake and Reduces Risk of Calcium Oxalate Stone Formation in Cats.

Simple SummaryIncreasing water intake and decreasing urine concentration are recommended for cats that form stony concretions in the bladder or urinary tract. The purpose of this study is to determine if water with increased viscosity results in increased water intake in cats by taking advantage of the unique anatomy of the cat’s tongue. Cats delicately dip their tongue into water, pull their tongues back up to their mouths, and capture the water that follows. Lapping occurs by fluid adhesion to the dorsal part of the tongue’s tip and by lifting a liquid column through the tongue’s upward motion before jaw closure. Cats have the ability to balance gravity and water surface tension to ingest the maximum amount of water per lap. This observation led us to question whether changing the properties of water in a way that allows cats to lift more water per lap is possible. Increasing the viscosity of water was accomplished with 1% methylcellulose, an ingredient that is palatable to cats. Cats consuming 1% methylcellulose water had increased water intake (25% and 21% higher at 28 and 56 days, respectively), and increased water intake reduces the risk for calcium oxalate stone formation. The benefit of giving cats viscous water is that they can increase water consumption without having to change their natural drinking behavior. The purpose of this study is to determine if water with increased viscosity results in increased water intake, thus lowering the risk of urolithiasis in cats. Twelve healthy adult cats were fed pre-trial standard dry maintenance food for 1 week and then randomized into two groups for the study phase. The cats continued to receive the same food but were provided either control (deionized) water or viscous (1% methylcellulose) water for two months and then switched to the other water type for two months in a cross-over study design with repeated measures. Complete blood counts, serum chemistry profiles, and urinalysis were performed at the initiation of the study and again at 1, 2, 3, and 4 months. Daily water consumption and energy intake for each cat were recorded. Body weights were assessed weekly. Cats consuming 1% methylcellulose water with increased viscosity had increased water intake (p < 0.001; 25% and 21% higher at 28 and 56 days, respectively). Increased consumption of water resulted in lower urine specific gravity (p = 0.04), serum creatinine (p = 0.02), and blood urea nitrogen (p = 0.002) concentrations (without changing serum albumin, glucose, and calcium concentrations or serum osmolality) and decreased urine calcium concentration (p = 0.01) compared with cats consuming control water. In addition, the increased water intake increased (p = 0.05) resistance to oxalate crystal formation.

Fructus Ligustri Lucidi aqueous extract promotes calcium balance and short-chain fatty acids production in ovariectomized rats

Ethnopharmacological relevanceFructus Ligustri Lucidi (FLL) is an edible herb with anti-osteoporotic activity, yet whether and how the aqueous extract of this herb affect calcium metabolism in preservation of bone quality remain unclear. Aim of the studyTo investigate the effects of FLL aqueous extract on calcium balance and short-chain fatty acids (SCFAs) production in ovariectomized (OVX) rats. Materials and methodsOVX rats were daily and orally administrated with FLL aqueous extract (3.5 g/kg) for 14 weeks. The levels of N-terminal propeptide of type I collagen (PINP) and C-terminal telopeptide of type I collagen (CTx-I) in rat serum were evaluated by ELISA assays. The concentration of calcium in serum, urine, and feces were determined by biochemical assays. Bone quality was determined by Micro-CT, a three-point bending assay, and Fourier Transform Infrared (FTIR) Spectrometry. The expressions of Calbindin D28K and Calcium-sensing receptor (CaSR) in kidney as well as the Vitamin D receptor (VDR), the transient receptor potential vanilloid receptor 6 (TRPV6), Calbindin D9k in the duodenum were measured by immunohistochemistry, western blotting, or real-time PCR. The short-chain fatty acids (SCFAs) levels in the feces of the cecum were tested by gas chromatograghy. ResultsThe administration of FLL to OVX rats resulted in a significant improvement in bone mineral density and biomechanical strength as well as in maintaining bone microstructures and material quality. Meanwhile, the decreased levels of PINP and increased levels of CTx-I in OVX rats were restored by FLL treatment. Additionally, FLL treatment increased calcium absorption, upregulated VDR, TRPV6, Calbindin D9k expressions in the duodenum, Calbindin D28K in kidney, and down-regulated CaSR expression in the kidney, as well as enhanced SCFAs levels in the feces of OVX rats. ConclusionsFLL aqueous extract may preserve bone quality through regulation of the calcium balance and intestinal SCFAs production in OVX rats. This offers translational value of FLL into osteoporosis clinical trial.

Acromegaly and non\u2010parathyroid hormone\u2010dependent hypercalcemia: a case report and literature review

BackgroundHypercalcemia associated with acromegaly is mostly parathyroid hormone (PTH)-dependent, being caused by parathyroid hyperplasia or adenoma, which are common in individuals with multiple endocrine adenomatosis-1 (MEN-1). The rare occurrence of non-PTH-dependent hypercalcemia associated with acromegaly is attributable to complex factors involving increased intestinal calcium absorption, enhanced bone calcium release, and reduced urinary calcium elimination. Although patients with acromegaly often have mild hyperphosphatemia and hypercalciuria, clinically significant hypercalcemia is extremely rare.Case presentationHere we present a case of non-PTH-dependent hypercalcemia associated with a growth hormone- (GH) and prolactin- (PRL) co-secreting pituitary macroadenoma. A 37-year-old Chinese man presented with a 6-year history of increasing ring and shoe sizes and was referred to the West China Hospital of Sichuan University for treatment of acromegaly. Pituitary magnetic resonance imaging (MRI) showed a 2.0 × 1.7 × 1.9 cm macroadenoma. Laboratory examinations revealed high serum concentrations of GH and PRL with mild hypercalcemia, hyperphosphatemia, hypercalciuria, inhibited PTH concentration, and increased bone turnover markers. Administration of cabergoline together with somatostatin resulted in sharp decreases in his GH, PRL, and serum and urinary calcium concentrations. These values were further reduced 5 months later and his PTH and bone turnover markers gradually returned to within the normal range.ConclusionsMild hyperphosphatemia and hypercalciuria are common in individuals with acromegaly and deserve attention because they may contribute to osteoporosis and urolithiasis. However, overt hypercalcemia is rare in such individuals. It is usually attributable to a coexisting parathyroid hyperplasia or adenoma, rarely being non-PTH-dependent. In such cases, the hypercalcemia is attributable to excessive PRL and hypogonadism and reverses with remission of acromegaly.

Switching from conventional therapy to burosumab injection has the potential to prevent nephrocalcinosis in patients with X-linked hypophosphatemic rickets.

X-linked hypophosphatemic rickets (XLH) is a congenital fibroblast growth factor (FGF)23-related metabolic bone disease that is treated with active vitamin D and phosphate as conventional therapies. Complications of these therapies include nephrocalcinosis (NC) caused by excessive urine calcium and phosphate concentrations. Recently, an anti-FGF23 antibody, burosumab, was developed and reported to be effective in poorly-controlled or severe XLH patients. This study aimed to reveal the impact of switching treatments in relatively well-controlled XLH children with the Rickets Severity Scale less than 2.0. The effects of the two treatments in eight relatively well-controlled XLH children with a mean age of 10.4 ± 1.9 years were compared retrospectively for the same treatment duration (31 ± 11 months) before and after the baseline. Actual doses of alfacalcidol and phosphate as conventional therapy were 150.9 ± 43.9 ng/kg and 27.5 ± 6.3 mg/kg per day, respectively. Renal echography revealed spotty NC in 8/8 patients, but no aggravation of NC was detected by switching treatments. Switching treatments increased TmP/GFR (p=0.002) and %TRP (p<0.001), and improved the high urine calcium/creatinine ratio to the normal range (p<0.001) although both treatments controlled disease markers equally. Additionally, low intact parathyroid hormone during conventional therapy was increased within the normal range by switching treatments. Our results suggest that a high dose of alfacalcidol was needed to control the disease, but it caused hypercalciuria and NC. We concluded that switching treatments in relatively well-controlled XLH children improved renal phosphate reabsorption and decreased urine calcium extraction, and may have the potential to prevent NC.

The effect of urine acidification on calcium oxalate relative supersaturation in cats.

There is an apparent reciprocal relationship between magnesium ammonium phosphate (MAP, struvite) and calcium oxalate (CaOx) urolithiasis incidence rate in cats. The number of struvite uroliths submitted for analysis over the past 35 years has been decreasing, with an increase in CaOx urolith submissions. Commercial diets aimed to dissolve struvite uroliths are typically acidified, and it has been suggested that dietary acidification increases urinary calcium excretion and the risk of CaOx crystallization. The objective of this study was to assess the effect of urine acidification on the relative supersaturation (RSS) of CaOx in cats, as a representation of crystallization risk. Four diets were extruded to contain identical nutrient contents, but with gradual acidification (0, 0.6, 1.3 and 1.9% sodium bisulphate substituted sodium chloride in diets A, B, C and D respectively). Thirteen adult cats were fed each diet sequentially for a minimum of 10 days. Average urine pH was 6.4, 6.2, 6.0 and 5.9 on diets A, B, C and D respectively (p < 0.0001). Struvite RSS decreased on diets inducing more acidic urine pH (p < 0.0001). Urinary calcium excretion and concentration increased with diets inducing lower urine pH (p < 0.0001), but oxalate excretion and concentration decreased (p < 0.001). CaOx RSS was not different between diets (p = 0.63). These results suggest that a lower diet base excess and resulting urine pH to support struvite dissolution do not increase the risk for CaOx crystallization in the range of urine pH representative of most commercial feline diets. Long‐term studies are needed to confirm this.

Characteristics of calcium homeostasis in patients with different degrees of arterial hypertension

Background: Calcium is the most common cation in the human body. An abnormal distribution of intracellular and extracellular ionized Ca plays a significant role in the formation of arterial hypertension. The purpose of the study is to analyze the fractional composition of calcium in blood serum and urinary calcium excretion in patients with hypertension, as well as to identify the features of the distribution of these. Material and methods: The study included 80 patients. The population of the study consisted of 60 patients with various degrees of hypertension (38 women and 22 men) aged from 65 to 74 years old and the control group composed of 20 patients (12 men and 8 women) in the same age group without signs of hypertension. The patients with clinically expressed coronary heart disease requiring specific therapy, heart defects, impaired liver function and impaired kidney function were excluded from this study. Patients were divided into three groups, according to the World Health Organization (WHO) classification of arterial hypertension. Indicators of calcium concentration in blood and urine were determined using test kits for determining calcium with glyoxal bis-2 hydroxyanil from LACHEMA. To determine the ionized calcium, a standard technique of ion-selective electrode was used. Results and conclusion: In patients with arterial hypertension, a redistribution of the calcium pool in the blood is noted due to a decrease in the concentration of ionized calcium and an increase in the bound calcium, depending on the severity of the disease. An increase in urinary calcium excretion in patients with arterial hypertension is characteristic of moderate and severe forms of arterial hypertension, which given the age of patients, may be one of the causes of osteoporosis. The increase in the level of intracellular calcium with the progression of arterial hypertension is an example of pathophysiological reactions that occur at the body level, the result of which can be not only banal muscle constriction but also a violation of the synthesis and production of biologically active substances that regulate blood pressure.

Hypercalciuria in Sarcoidosis: A Specific Biomarker With Clinical Utility.

Background: Changes in calcium metabolism are quite common in sarcoidosis: hypercalciuria is linked to a persistent clinical phenotype and more active disease. No data is yet available on the specificity of parameters of calcium metabolism as biomarkers for distinguishing different chronic interstitial lung diseases (ILD). Here we assessed calcium metabolism in an Italian population of sarcoidosis patients, which included a group with stage IV fibrotic disease, and compared the results with those of idiopathic pulmonary fibrosis (IPF) and chronic hypersensitivity pneumonitis (cHP) patients.Population and Methods: We recruited sarcoidosis, IPF and cHP patients retrospectively. All patients were diagnosed through multidisciplinary discussion and were monitored at the Regional ILD Referral Centre in Siena. Clinical, radiological, functional, immunological and laboratory parameters were collected and entered in an electronic database for data analysis.Results: A total of 305 patients (237 sarcoidosis, 40 IPF and 28 cHP) were enrolled. Sarcoidosis patients included a predominance of females and were significantly younger than IPF and cHP patients (p < 0.0001 for both). In the sarcoidosis population, 17 patients (7.2%) showed radiological evidence of lung fibrosis, according the Scadding classification; fibrotic disease was also confirmed by CT scan. Concerning calcium metabolism, sarcoidosis patients showed significantly higher serum and urinary concentrations of calcium than IPF and cHP patients (p = 0.0004 and p < 0.0001, respectively). These findings were also confirmed when comparing groups with fibrotic sarcoidosis, IPF and cHP (p = 0.0237 and p = 0.0138). According to receiver operating characteristics (ROC) curve analysis, urinary calcium showed better diagnostic accuracy than serum calcium in discriminating sarcoid and non-sarcoid lung fibrosis (AUC 0.7658 vs. 0.6205; p = 0.0026 vs. p = 0.1820).Discussion: Our results confirmed that changes in calcium metabolism, particularly hypercalciuria, occur in a substantial percentage of patients with sarcoidosis. Higher serum and urinary concentrations of calcium were found than in IPF and cHP; the same results were observed when the comparison was limited to patients with fibrotic sarcoidosis, supporting the hypothesis that dysregulation of calcium metabolism may be a special feature of sarcoid granulomas. Hypercalciuria distinguished fibrotic sarcoidosis from IPF and cHP, suggesting that assessment of calcium metabolism may be useful in the diagnostic pathway of ILDs.

Dynamics of Restoration of Functional State of the Kidney Parenchyma and Normalization of Main Risk Factors of Calcium-oxalate Nephrolithiasis in Urine on the Background of Using Complex Metaphylaxis

The objective: to investigate the dynamics of restoration of the functional state of the renal parenchyma by levels of N-acetyl-β-D-glucosaminidase (NAG) activity in urine and normalization of the main risk factors of calcium-oxalate nephrolithiasis (Ca-Ox NL) – by concentrations of calcium, oxalic and uric acids in urine on the background of application of complex metaphylaxis within a year after stone removal.Materials and methods. 45 patients with Ca-Ox NL before and after the removal of concrements in 1, 3, 6 and 12 months on the background of the use of complex metaphylaxis were examined. The activity of the conditionally renospecific enzyme NAG and concentration of calcium, oxalic and uric acids were analyzed. The personification of metaphylactic measures was performed depending on the characteristics of the risk factors for the development of Ca-Ox NL: the combination of hyperoxaluria with hyperuricemia and hyperuricuria, the combination of hyperoxaluria with hyperuricemia, the presence of significant hyperoxaluria on the background of normouricemia and normouricuria and also depending on hypercalciuria. The control group consisted of 28 practically healthy persons with normal analysis of urine and free of renal diseases.Results. In patients with NL before the removal of the stone, the activity of NAG, calcium, oxalic and uric acid concentrations probably exceeded the control data. In the dynamics of observation there is a gradual decrease in urinary NAG activity, calcium, oxalic and uric acid concentrations. NAG activity and uric acid concentration did not differ from the data in the control group after 12 months, calcium – after 3 months, oxalic acid concentration after 6 months.Conclusion. Restoration of the functional state of tubular nephrotheoia and normalization of concentrations of the main risk factors for the development of Ca-Ox NL on the background of complex metaphylaxis was achieved in almost 95 % of cases. The obtained results can be used to correct and optimize the treatment tactics of patients with Ca-Ox NL after removal of the calculus during the year.

Proof-of-concept study: Evaluation of plasma and urinary electrolytes as markers of response to L-asparaginase therapy in dogs with high-grade lymphoma.

Response to chemotherapy is one of the most important prognostic factors in dogs with lymphoma. The objective of this feasibility study was to evaluate if clinical responses to a specific cytotoxic agent (L-asparaginase) could be anticipated by measuring analyte concentrations in plasma and urine concentrations of lymphoma-bearing dogs. We hypothesized that potassium and phosphate concentrations in plasma and urine would be higher in dogs that completely responded to therapy. Plasma and urine samples of dogs with lymphoma were obtained before 12 and 24hours after intramuscular L-asparaginase injections. Peripheral lymph node volumes were evaluated according to the Veterinary Cooperative Oncology Group standardized criteria. Plasma and urine electrolyte, calcium, phosphate, creatinine, urea, total protein, and albumin concentrations were measured, and the fractional excretions of each electrolyte were calculated. Statistical analyses compared complete vs partial responders using a linear regression model. Contrast analyses were also performed to differentiate the mean of each group, with adjustments made with the Benjamini-Hochberg procedure. Fourteen dogs were included, eight with complete responses, and six with partial responses. Plasma phosphate concentrations were significantly higher at 12hours (P=.0003) and 24hours (P=.009) after complete responses to therapy. This study demonstrates the potential use of plasma and urine analyte monitoring after chemotherapy induction. Plasma phosphate measurements represent a potential indicator of early responses to L-asparaginase therapy. Larger population studies are warranted to confirm these preliminary results.

Race, Ancestry, and Vitamin D Metabolism: The Multi-Ethnic Study of Atherosclerosis.

A comprehensive characterization of racial/ethnic variations in vitamin D metabolism markers may improve our understanding of differences in bone and mineral homeostasis and the risk of vitamin D-related diseases. Describe racial/ethnic differences in vitamin D metabolism markers and their associations with genetic ancestry. In a cross-sectional study within the Multi-Ethnic Study of Atherosclerosis (MESA), we compared a comprehensive panel of vitamin D metabolism markers across self-reported racial/ethnic groups of Black (N = 1759), White (N = 2507), Chinese (N = 788), and Hispanic (N = 1411). We evaluated associations of proportion African and European ancestry with this panel of markers in Black and Hispanic participants using ancestry informative markers. Latent class analysis evaluated associations between patterns of vitamin D measurements with race/ethnicity. Compared with Black participants, White participants had significantly higher serum concentrations of 25-hydroxyvitamin D and fibroblast growth factor-23; lower concentrations of parathyroid hormone and 1,25-dihydroxyvitamin D; circulating vitamin D metabolite ratios suggesting lower CYP27B1 and higher CYP24A1 activity; higher urinary concentrations of calcium and phosphorus with higher urinary fractional excretion of phosphorus; and differences in vitamin D binding globulin haplotypes. Higher percent European ancestry was associated with higher 25-hydroxyvitamin D and lower parathyroid hormone concentrations among Black and Hispanic participants. Latent classes defined by vitamin D measurements reflected these patterns and differed significantly by race/ethnicity and ancestry. Markers of vitamin D metabolism vary significantly by race/ethnicity, may serve to maintain bone and mineral homeostasis across ranges of 25-hydroxyvitamin D production, and be attributable, at least partly, to genetic ancestry.

Sensing of electrolytes in urine using a miniaturized paper-based device

Analyzing electrolytes in urine, such as sodium, potassium, calcium, chloride, and nitrite, has significant diagnostic value in detecting various conditions, such as kidney disorder, urinary stone disease, urinary tract infection, and cystic fibrosis. Ideally, by regularly monitoring these ions with the convenience of dipsticks and portable tools, such as cellphones, informed decision making is possible to control the consumption of these ions. Here, we report a paper-based sensor for measuring the concentration of sodium, potassium, calcium, chloride, and nitrite in urine, accurately quantified using a smartphone-enabled platform. By testing the device with both Tris buffer and artificial urine containing a wide range of electrolyte concentrations, we demonstrate that the proposed device can be used for detecting potassium, calcium, chloride, and nitrite within the whole physiological range of concentrations, and for binary quantification of sodium concentration.

Calcium Deficiency in Diet Decreases the Magnesium Content in Bone and Affects Femur Physicochemical Properties in Growing Rats.

This study evaluates the effect of three calcium levels in the diet (normal, moderate, and severe calcium depletion) on bone metabolism of male Wistar rats during their growth period. Bone mineral density (BMD) and femur length were determined in vivo during the growth stage using a single X-ray transmission system. The apparent calcium absorption was calculated in the rat adolescent and adulthood stages. At the end of the experiment, calcium concentrations in serum and urine were analyzed. The bones were evaluated postmortem to corroborate in vivo analyses. Microstructural properties of cortical and trabecular tissues of femurs bones were assessed using scanning electron microscopy. Bone mineral contents (Mg, Ca, P, and K) were quantified by inductively coupled plasma. Severe calcium depletion in the diets in the development stage affects the bone quality parameters such as bone mineral density and mineral content. Moreover, it was found thinner cortical and trabecular bone areas. Additionally, it was found that severe calcium depletion increased the apparent absorption of calcium as a defense mechanism, but with the decrease of the BMD peak, and the thickness of cortical bone as well as trabecular bone porosity. The severe calcium depletion increased the efficiency of apparent absorption calcium as a defense mechanism, but, even so, decreases the BMD peak as well as the thickness of cortical bone and trabecular bone porosity.

Efek Antikalkuli Ekstrak Etanol Herba Seledri (Apium graveolens L.) terhadap Tikus yang Diinduksi Hidroksiprolin

The investigation efforts of an alternative treatment of the kidney stone disease by utilizing Indonesian native plants have still continued both for treatment and prevention. This study aims to strengthen the scientific evidence of the activity of celery as an anticalculi by in vivo assessment using hydroxyprolineinduced rat method. The white male wistar rats used in this study were intraperitoneally induced by hydroxyproline in order to form kidney stones, the celery extract preparations were then given at a dose of 50, 100, and 200 mg/kg of body weight orally for 5 days and observed following parameters: concentration of filtrate urinary calcium, concentration of urinary sediment calcium, as well as kidney to body weight ratio. The results showed that the concentration of filtrate urinary calcium in the test group at a dose of 200 mg/ kg body weight was significantly higher than those of negative control group, whereas the other test groups were not significantly different with the negative control group. The similar result was also shown on the parameter of calcium concentration in the urine sediment, while the ratio of kidney to body weight showed significant differences between all test groups and the negative control group. It can be concluded that the ethanol extract of the herb celery has an anticalculi activity in rats at a dose of 200 mg/kg of body weight.

PSIII-36 Increased viscosity enhances water intake and reduces risk of calcium oxalate stone formation in cats

Abstract The control of liquid intake in cats is especially of interest as there is a significant risk of urinary tract stone formation due to their high urinary solute density. Calcium oxalate stone formation is not easily mitigated by dietary manipulation. This study investigated if increasing water viscosity (282 vs 2.9 centipoise; means throughout are viscous water followed by control cats) improved voluntary intake of water and calcium oxalate stone risk. Twelve cats (7 neutered males, 5 spayed females) from 3 to 8 years of age with an average weight 4.7 kg were monitored for 4 months. Each cat spent 2 months consuming viscous water and two months consuming normal water in a crossover design. Water consumption was measured through loss of weight from each pet’s water bowl with an additional bowl of the consumed viscosity placed in the room for evaporative loss measurements. A urine calcium oxalate titrimetric test (COT) was performed to evaluate the risk of calcium oxalate stone formation. In brief, the [Ca+2]/(added Oxalate-2) ratio is calculated (per liter). An increasing index value denotes samples at greater risk of calcium oxalate crystallization. The ratio represents the concentration of ionized calcium and the amount of oxalate that is added to initiate crystallization. The results showed that cats drinking viscous water had a significant increase in water consumption (79.9 vs 65.6 grams P = 0.014). There was a reduction in urine specific gravity (1.042 vs 1.052 P = 0.016), fractional excretion of calcium (0.197 vs 0.280 P = 0.036), urinary calcium concentration (49.8 vs 61.8 ppm P &amp;lt; 0.01) and in stone risk as measured by COT (35.5 vs 82.4 P = 0.029). In conclusion, these data show that there is an increased intake of water when cats are offered water with increased viscosity and increased viscosity was associated with an improvement in measurements of oxalate stone risk.