Calcium-phosphate Product Research Articles

Efficacy and safety of paricalcitol in patients undergoing hemodialysis: a meta-analysis.

BackgroundThe elevated calcium and phosphorus levels in patients undergoing hemodialysis may increase the risk of all-cause mortality. Paricalcitol, as a new vitamin D receptor activator (VDRA), seemed to be effective in reducing the calcium and phosphorus levels.ObjectivesThe aim of this study was to compare the efficacy and safety of paricalcitol with other VDRAs in patients undergoing hemodialysis.MethodsPubMed, Embase, and Web of Science database were systematically reviewed.Selection criteriaStudies that focused on the use of paricalcitol for hemodialysis patients were eligible for inclusion.Data collection and analysisTwo independent investigators performed the literature search, data extraction, and assessment of methodological quality. The outcomes were expressed with standard mean difference (SMD), HR, or risk ratio (RR) with 95% CI.ResultsThirteen studies involving 112,695 patients were included in this meta-analysis. Among these studies, four studies were cohort studies and nine studies were randomized controlled trials (RCTs). For cohort studies, they were regarded as being of high quality; for RCTs, only one was classified as being at low risk of bias; and the remaining eight studies were at being unclear risk of bias. Compared with other VDRAs, paricalcitol significantly improved the overall survival (HR =0.86, 95% CI: 0.80, 0.92; P<0.001) and reduced the intact parathyroid hormone (iPTH) (SMD =−0.53, 95% CI: −0.90, −0.17; P=0.004). Paricalcitol offered similar effect with other VDRAs in the control of calcium (SMD =0.32, 95% CI: −0.04, 0.67; P=0.078) and phosphorus (SMD =0.06, 95% CI: −0.26, 0.37; P=0.727) levels. However, the serum change in calcium phosphate product was greater in the paricalcitol group than in the other VDRA group (SMD =2.13, 95% CI: 0.19, 4.07; P=0.031). There was no significant difference in the incidence of adverse events between the two groups (RR =1.02, 95% CI: 0.93, 1.12; P=0.674).ConclusionParicalcitol was crucial in reducing the mortality in patients undergoing hemodialysis. Moreover, both paricalcitol and other VDRAs were effective in control of the serum iPTH, calcium, and phosphorus levels. Given the potential limitations in this study, more prospective large-scale, well-conducted RCTs are needed to confirm these findings.

Magnesium but not nicotinamide prevents vascular calcification in experimental uraemia.

Optimal phosphate control is an unmet need in chronic kidney disease (CKD). High serum phosphate increases calcification burden and is associated with mortality and cardiovascular disease in CKD. Nicotinamide (NA) alone or in combination with calcium-free phosphate binders might be a strategy to reduce phosphate levels and calcification and thus impact cardiovascular disease in CKD. We studied the effect of NA alone and in combination with magnesium carbonate (MgCO3) as a potential novel treatment strategy. CKD was induced in dilute brown non-agouti/2 mice by subtotal nephrectomy followed by a high-phosphate diet (HP) and 7 weeks of treatment with NA, MgCO3 or their combination. Control mice underwent subtotal nephrectomy and received an HP or underwent sham surgery and received standard chow plus NA. CKD mice showed increased serum fibroblast growth factor 23 and calcium-phosphate product that was normalized by all treatment regimes. NA alone increased soft tissue and vascular calcification, whereas any treatment with MgCO3 significantly reduced calcification severity in CKD. While MgCO3 supplementation alone resulted in decreased calcification severity, it resulted in increased intestinal expression of the phosphate transporters type II sodium-dependent phosphate transporter 1 (Pit-1). Combined therapy of MgCO3 and NA reduced tissue calcification and normalized expression levels of intestinal phosphate transporter proteins. In conclusion, the data indicate that NA increases while MgCO3 reduces ectopic calcification severity. Augmented expression of intestinal phosphate transporters by MgCO3 treatment was abolished by the addition of NA. However, the clinical relevance of the latter remains to be explored. Importantly, the data suggest no benefit of NA regarding treatment of calcification in addition to MgCO3.

Elevated admission serum calcium phosphate product as an independent risk factor for acute kidney injury in hospitalized patients

ABSTRACTBackground: Increased serum calcium-phosphate product (CaP) can result in acute kidney injury (AKI) due to tubular and interstitial calcium phosphate deposits. CaP of > 55 mg2/dL2 is also associated with systemic calcification. However, the risk of AKI development among hospitalized patients with different admission calcium-phosphate product levels remains unclear.Methods: All adult hospitalized patients who had both admission serum calcium and phosphate levels available from 2009 through 2013 were enrolled. Admission CaP was categorized based on its distribution into six groups (<22, 22- < 27, 27- < 32, 32- < 37, 37- < 42 and ≥42 mg2/dL2). The odds ratio (OR) of in-hospital mortality by admission CaP, using the CaP category of < 22 mg2/dL2 as the reference group, was obtained by logistic regression analysis.Results: After excluding patients with end-stage renal disease, without serum creatinine measurement, and those who presented with AKI at the time of admission, a total of 9,864 patients were studied. In-hospital AKI occurred in 1,478 patients (15.0%). The incidence of AKI among patients with admission CaP < 22, 22 to < 27, 27 to < 32, 32 to < 37, 37 to < 42, and ≥42 mg2/dL2 was 11.1%, 12.4%, 14.9%, 15.2%, 17.5%, and 19.9%, respectively. After adjusting for potential confounders, a CaP ≥37 mg2/dL2 was associated with an increased risk of developing AKI with OR of 1.53 (CI 1.19–1.96) and 1.63 (CI 1.25–2.14) in patients with admission CaP 37- < 42 and ≥42, respectively. Subgroup analysis based on eGFR consistently demonstrated that CaP ≥37 mg2/dL2 was associated with an increased risk of developing AKI in both chronic kidney disease (CKD) and non-CKD patients.Conclusion: Elevated admission CaP was independently associated with an increased risk for in-hospital AKI.

Dialysis vintage and risk factors of hyperparathyroidism in hemodialysis patients

Objective The objective of this study was to study the risk factors of hyperparathyroidism based on hemodialysis vintage (duration in months or years that hemodialysis patients spend on dialysis). Background Hyperparathyroidism is associated with high risk of fractures, cardiovascular morbidity, and death; therefore, it is important to identify risk factors predicting or influencing parathyroid gland secretion. Patients and methods Patients were divided into two groups: short dialysis vintage ( Results Short dialysis vintage patients with PTH more than 300 pg/ml have higher alkaline phosphatase (147.9 ± 101.4 vs. 102.1 ± 89.18; P = 0.009), phosphorus (5.913 ± 1.621 vs. 5.044 ± 1.387; P = 0.048), calcium phosphate product (49.60 ± 13.45 vs. 42.35 ± 13.61; P = 0.04), and serum creatinine (10.8 ± 3.353 vs. 8.96 ± 2.311; P = 0.005 for predialysis serum creatinine and 4.987 ± 1.364 vs. 4.035 ± 1.426; P = 0.007 for postdialysis serum creatinine) compared with nonhigh PTH group. Long dialysis vintage patients with PTH more than 300 pg/ml have higher alkaline phosphatase (222.1 ± 184.7 vs. 99 ± 29.47; P = 0.024), lower serum sodium (137.3 ± 2.8 vs. 141.4 ± 2.937; P = 0.004), and lower mean arterial blood pressure (81.42 ± 14.65 vs. 96.38 ± 12.87; P = 0.019) compared with nonhigh PTH group. Conclusion Serum alkaline phosphatase, phosphorus, calcium phosphate product, and serum creatinine were found to be associated with hyperparathyroidism in short hemodialysis vintage patients (

Prevalence and pattern of chronic kidney disease-mineral bone disorders among hemodialysis patients in kano, northwest nigeria.

Introduction:Mineral and bone disorders (MBD) are among the important complications of chronic kidney disease (CKD) including end-stage renal disease. In addition to the higher rate of all-cause and cardiovascular-related mortality, MBD is also a cause of significant morbidity in CKD patients.Materials and Methods:This is a cross-sectional study of all consenting patients on hemodialysis at Aminu Kano Teaching Hospital, between December 2011 and June 2012. With the aid of an interviewer-administered questionnaire, the demographic profile and clinical features of the patients were obtained. After a general physical examination, blood sample was taken for the determination of calcium, phosphate, intact parathyroid hormone, 25 hydroxy (25[OH]) Vitamin D3, packed cell volume, serum creatinine, and potassium.Results:Forty-eight patients on maintenance hemodialysis were recruited for the study, 39 (81.3%) were male and 9 (18.8%) were female. The age range was 40–59 years, with a mean of 45.96 ± 13.7 years. Chronic glomerulonephritis was the predominant cause of CKD (25%). Hyperphosphatemia was noted in 19 (39.5%) of the patients, whereas 22 (46%) had hypocalcemia. In 26 (54.1%) of the patients, the calcium-phosphate product was >4.55 mmol2/L2. We found that 58% of the patients had CKD-MBD, of which 15 (31%) had secondary hyperparathyroidism, whereas 13 (27%) had features suggestive of adynamic bone disease. None of the patient had normal serum 25(OH) Vitamin D3 (mean: 43.79 ± 21 ng/ml).Conclusion:CKD-MBD is common among patients on hemodialysis in our center. Screening for CKD-MBD and appropriate use of phosphate binder and Vitamin D when indicated are highly recommended.

Relationship Between SCUBE1 Levels and Echocardiography and Electrocardiography Findings and Epicardial Adipose Tissue/Carotid Intima-Media Thickness in Patients Receiving Renal Replacement Therapy.

In patients with advanced-stage chronic kidney disease, renal insufficiency, arterial stiffness, and vascular calcification are strong predictors of cardiovascular risk. Signal peptide-CUB-EGF-like protein-1 (SCUBE1) levels increase during platelet activation and acute ischemic events. Here, we evaluated associations between SCUBE1 levels and electrocardiographic/echocardiographic findings, epicardial adipose tissue thickness, and carotid intimamedia thickness in patients with chronic kidney disease. Our study included 21 renal transplant recipients, 20 peritoneal dialysis patients, 20 hemodialysis patients, 20 predialysis patients with glomerular filtration rate < 30 mL/min, and 16 healthy volunteers. We found no differences in SCUBE1 levels between patient groups and healthy volunteers, regardless of history of diabetes mellitus, myocardial infarction, cerebrovascular events, and hypertension. SCUBE1 levels correlated with C-reactive protein in renal transplant recipients; magnesium in peritoneal dialysis patients; erythrocyte sedimentation rate in predialysis patients; and parathyroid hormone, platelet count, calcium-phosphate product, and calcium in hemo dialysis patients. No associations were shown between SCUBE1 levels and electrocardiographic/echocardiographic findings. Elevated C-reactive protein in predialysis patients was associated with cardiac valvular pathologies. In hemodialysis patients, SCUBE1 levels increased after hemodialysis (P = .007). Levels were higher in healthy individuals with normal echocardiography and predialysis patients with left ventricular diastolic dysfunction. Positive correlations were found between carotid intima-media thickness and SCUBE1 levels in dialysis patients (P < .05), but no study groups showed correlations regarding epicardial adipose tissue thickness. Hemodialysis may contribute to cardiovascular events because of increased SCUBE1 levels after hemodialysis; however, no association was shown between SCUBE1 and electrocardiography/echocardiography findings. We found no correlations between epicardial adipose tissue thickness and SCUBE1 levels, and levels were significantly higher in healthy patients and in predialysis patients without left ventricular diastolic dysfunction. However, correlations were shown between SCUBE1 levels and carotid intima-media thickness and secondary hyperparathyroidism markers, indicating associations with atherosclerosis and bone mineral disease in dialysis patients.

Factors associated with carotid intima-media thickness in patients on maintenance hemodialysis.

PurposeThe aim of this study was to analyze the association of the carotid intima-media thickness (CIMT) with various parameters in patients on maintenance hemodialysis (mHD).MethodsA cross-sectional study was conducted, enrolling 68 subjects (41 men, 27 women) on mHD in the Hemodialysis Unit, Sanglah Hospital, Denpasar, Indonesia. CIMT was measured with B-mode ultrasonography using a USG Sonoace 8000 and a 7.5 MHz linear transducer.ResultsCIMT was higher in subjects with cardiovascular disease (CVD) compared with those without CVD (0.6494 vs 0.7288 mm; P=0.026), and in men compared with women (0.7056 vs 0.6141 mm; P=0.003). CIMT was correlated with age (R=0.607; P<0.001), plasma albumin (R=−0.291, P=0.016), serum phosphate (R=−0.294, P=0.015), calcium-phosphate product (R=−0.284, P=0.011), and plasma high-sensitivity C-reactive protein (R=0.279, P=0.030). However, after multiple linear regression testing, only age consistently had a role in determining the CIMT value (β=0.452, P<0.001).ConclusionSubjects with CVD have higher CIMT than those without CVD and men had higher CIMT than women. In addition, older age, higher high-sensitivity C-reactive protein, and lower albumin, phosphate, and calcium-phosphate product levels were correlated with higher CIMT. Age was the most important marker for CIMT in subjects on mHD.

Serum sclerostin as a potential novel biomarker for heart valve calcification in patients with chronic kidney disease.

To explore the correlation between change in sclerostin level and heart valve calcification in patients with chronic kidney disease (CKD) in stages 3-5, as well as the possible underlying mechanism, which could provide a clinical reference for the diagnosis and treatment of cardiovascular disease (CVD). 110 patients were divided into a healthy control group and three groups of patients with CKD stages 3, 4, and 5 according to CKD staging guidelines. Scr, BUN, AKP, TC, TG, HDL, LDL, Ca, Pi, and CRP were measured, and calcium-phosphate product (Ca×Pi) calculated. ELISA was used to measure the sclerostin level, and the estimated glomerular filtration rate (eGFR) was calculated by MDRD. Heart valve calcification was measured by a physician in the Cardiac Department of our hospital. The correlations between sclerostin-level change and heart valve calcification, as well as each index in CKD patients in stages 3-5, were analyzed. Compared with the healthy control group, the serum Ca in CKD stage-3, stage-4, and stage-5 groups (p < 0.05) was reduced, and PTH was increased (p < 0.05). Blood Pi and Ca×Pi in the stage-4 and stage-5 groups were increased (p < 0.05). The serum sclerostin level increased with renal hypofunction in stage-3 CKD patients, and was significantly increased compared with that of the control group, reaching the highest level in the terminal stage (p < 0.01). Pearson correlation analysis indicated that serum sclerostin was negatively correlated with eGFR (r = -0.91, p < 0.001) and blood Ca (r= -0.271, p < 0.001), and positively correlated with SCr (r = 0.608, p < 0.001), blood Pi level (r = 0.295, p < 0.001), PTH (r = 0.334, p < 0.001), and Ca×Pi (r = 0.275, p < 0.001). The rate of heart valve calcification in the CKD patients in stage 5 was relatively high (11/30, 36.67%), and significantly higher than that in healthy controls (1/20, 5%; p < 0.01). Logistic regression analysis of heart valve calcification indicated that sclerostin was a risk factor for heart valve calcification in CKD patients in stages 3-5. The sclerostin level gradually increased with renal hypofunction in CKD patients in stages 3-5, and the increase in serum sclerostin level in the CKD patients occurred earlier than the change in Pi and Ca×Pi. The risk of heart valve calcification in stage-5 CKD patients was significantly increased. Sclerostin is an independent risk factor for heart valve calcification in CKD patients.

Calcium phosphate product level as a predictor for arteriovenous fistula re-operations in patients with chronic renal failure.

There is an increased calcium phosphate product level causing the formation of calcification in the arterial wall and thus decreased quality of fistula in patients with chronic renal failure. The purpose of our study is to verify the relationship between arteriovenous fistula re-operation and high calcium phosphate product level. Seventy-nine consecutive patients with chronic renal failure between April 2016 and February 2018 were included in the study. Patients having calcium phosphate product level ≥50mg2/dl2 were defined as group 1, whereas those having <50mg2/dl2 were defined as group 2. Primary outcome of interest was the need for re-operation during the follow-up and to determine the risk factors for re-operation. To determine independent predictors for re-operation, multivariate logistic regression model was used. The rates of redo and tredo operation were significantly higher in group 1 compared to group 2 ( p = 0.01 and 0.04). In multivariate analysis, phosphate (OR: 1.84, 95% CI: 1.00-3.40, p = 0.05) and triglyceride (OR: 1.01, 95% CI: 1.00-1.02, p = 0.04) levels for redo operation and calcium phosphate product level (OR: 1.11, 95% CI: 1.01-1.22, p = 0.03) for tredo operation were found to be independent predictors. High calcium phosphate product level leads to increased risk of arteriovenous fistula re-operation by causing arterial stiffness in this patient group. Additionally, these re-operations place additional burden on morbidity and cost efficacy. Thus, we recommend keeping the calcium phosphate product level at the optimal level in these patients to avoid both the risk of arteriovenous fistula re-operation and the other cardiovascular problems.

Scanning electron microscopy for blood micro-crystals in aortic stenosis patients.

BackgroundMicro-crystals of calcium phosphate have been detected on the aortic valve of patients with aortic stenosis using scanning electron microscopy. It is not known whether crystalisation is specific to heart valve tissue or a general blood-derived process.MethodsTo this end we modified the method to determine whether calcium phosphate micro-crystals were present in the blood of patients with aortic stenosis. The method was first validated by adding synthetic calcium phosphate hydroxyapatite micro-crystals to healthy volunteer blood samples and determining the lower limit of detection. Then the method was used to examine the blood of 63 patients with echocardiographically confirmed aortic stenosis and 69 unaffected controls undergoing echocardiography for other reasons. Serum calcium and phosphate were measured and the calcium phosphate product compared in cases and controls.ResultsIn the validation study, synthetic hydroxyapatite micro-crystals were identified down to a lower concentration limit of 0.008mg/mL. In the experimental study no particles were identified in any patient, with or without aortic stenosis, even though serum calcium phosphate was higher in cases compared with controls 2.6mmol/L (2.58–2.77) versus 2.47mmol/L (2.36–2.57), p = 0.005 for the difference.ConclusionThe results of our study confirm a positive association between serum calcium phosphate and aortic stenosis, but indicate that the calcium phosphate particles found in valve tissue do not precipitate freely in the blood.

The importance of fetuin-A in vascular calcification in children with chronic kidney disease.

The status of the cardiovascular (CV) system in children with chronic kidney disease (CKD) is significantly influenced by increasing stiffness of the arterial wall. This largely depends on the shortage of local and systemic inhibitors of soft tissue calcification. The aim of the study was to evaluate the role of fetuin-A in conjunction with other factors in the progressive hardening of the vascular wall in these children. We examined serum fetuin-A concentrations in relation to renal function, dialysis modality, and other clinical and biochemical markers promoting vascular calcification. Twenty children on peritoneal dialysis (PD), 20 on hemodialysis (HD), 36 treated conservatively, and 26 healthy subjects were enrolled into a cross-sectional study. In all children, fetuin-A and numerous clinical and biochemical parameters were measured. The fetuin-A concentration was significantly lower in children on hemodialysis (HD) vs children on peritoneal dialysis (PD), conservatively treated subjects, and the control group. In sick children, fetuinA concentration negatively correlated with dialysis vintage, PWV/ht, phosphate concentration, calcium phosphate product (CaxP), cumulative doses of calcium, and vitamin D3. In the whole study population, fetuin-A negatively correlated with blood pressure (BP), pulse wave velocity indexed to height (PWV/ht), intact parathyroid hormone (iPTH), high sensitivity C-reactive protein (hsCRP), and cholesterol concentrations. In children with CKD, the decreased concentration of fetuin-A is related to other vascular calcification risk factors. Serum fetuin-A concentration may play a role in the identification of vascular disease risk factors in this population.

Economic Recovery of Calcium Phosphates From Swine Lagoon Sludge Using Quick Wash Process and Geotextile Filtration

To maintain the waste treatment capacity of anaerobic swine lagoons, excessive accumulation of sludge in the bottom of the lagoon is traditionally removed by dredging and pumping followed by dewatering prior to land application. A widespread and low-cost method of dewatering this lagoon sludge in U.S. farms is the use of geotextile bag filtration. Because of typically high phosphorus (P) contents in lagoon sludge, the dewatered sludge is eventually hauled to distant fields to reduce the environmental risk of excess P in land nearby the lagoon. The inclusion of a P recovery approach, called Quick Wash (QW), along with the geotextile bag technology could eliminate or reduce hauling costs of dewatered sludge and produce a valuable P product for use as fertilizer. The QW process uses a novel combination of acid, base, and organic polyelectrolytes to selectively extract and recover P from manure solids. The objective of this study was to evaluate the potential advantage and technical feasibility of combining the QW process and geotextile dewatering in a system to extract and recover P from lagoon sludge. Laboratory tests results showed that the amount of recoverable P from lagoon sludge depends on the pH level obtained by acidification. The highest release of P in solution, 83% of total initial P, was obtained when the lagoon sludge was acidified to pH 3. The amount of P recovered as a precipitate with lime addition at pH 10 was about 79% of the initial total P in the sludge. A mass flow balance confirmed that about 20% of the total P remained in the dewatered sludge solids. The effluent contained extremely low soluble P concentrations. The calcium phosphate product was identified as amorphous calcium phosphate (ACP) with very low heavy metal content. The recovered ACP had P grades (33.2 to 35.5 % P2O5), higher than rock phosphate, with the advantage that there is no need for additional chemical processing for its use as fertilizer. Results of this study support the technical feasibility of using the QW process in combination with geotextile bag filtration for the economic recovery of P from anaerobic swine lagoons.

Anti-cytomegalovirus IgG antibody titer is positively associated with advanced T cell differentiation and coronary artery disease in end-stage renal disease

BackgroundAccumulating evidence indicates that persistent human cytomegalovirus (HCMV) infection is associated with several health-related adverse outcomes including atherosclerosis and premature mortality in individuals with normal renal function. Patients with end-stage renal disease (ESRD) exhibit impaired immune function and thus may face higher risk of HCMV-related adverse outcomes. Whether the level of anti-HCMV immune response may be associated with the prognosis of hemodialysis patients is unknown.ResultsAmong 412 of the immunity in ESRD study (iESRD study) participants, 408 were HCMV seropositive and were analyzed. Compared to 57 healthy individuals, ESRD patients had higher levels of anti-HCMV IgG. In a multivariate-adjusted logistic regression model, the log level of anti-HCMV IgG was independently associated with prevalent coronary artery disease (OR = 1.93, 95% CI = 1.2~ 3.2, p = 0.01) after adjusting for age, sex, hemoglobin, diabetes, calcium phosphate product and high sensitivity C-reactive protein. Levels of anti-HCMV IgG also positively correlated with both the percentage and absolute number of terminally differentiated CD8+ and CD4+ CD45RA+ CCR7- TEMRA cells, indicating that immunosenescence may participate in the development of coronary artery disease.ConclusionThis is the first study showing that the magnitude of anti-HCMV humoral immune response positively correlates with T cell immunosenescence and coronary artery disease in ESRD patients. The impact of persistent HCMV infection should be further investigated in this special patient population.

Predictors of Renal Function and Calcifications in Primary Hyperparathyroidism: A Nested Case-Control Study.

Some patients with primary hyperparathyroidism (PHPT) develop renal calcifications. Investigation of urinary and nonurinary risk factors are essential. We aimed to study the prevalence and potential biochemical predictors of renal calcifications. Nested case-control study. University hospital. We identified 792 patients with PHPT from 2005 to 2015. We used biochemical data to validate the diagnosis of PHPT. The prevalence of renal calcifications defined as nephrolithiasis or nephrocalcinosis assessed by a routine CT scan at the time of diagnosis. A total of 792 patients with PHPT were identified among whom 617 patients (78%) had a CT scan preformed. We found a prevalence of renal calcifications of 23%, equally frequent between sexes. A total of 76 patients (12%) had nephrolithiasis and 75 patients (12%) had nephrocalcinosis where 7 patients (1%) had both nephrolithiasis and nephrocalcinosis. Compared with patients without renal calcifications, patients with renal calcifications had significantly higher levels of ionized calcium, parathyroid hormone, and 24-hour calcium excretion (Pall < 0.01). Patients with nephrocalcinosis had higher plasma levels of phosphate and a higher calcium-phosphate product compared with patients with nephrolithiasis (Pall < 0.05). Impaired renal function (estimated glomerular filtration rate <60 mL/min) was observed in 12% of patients. However, no differences in renal function were observed between those with and without renal calcifications. Renal calcifications are frequent in patients with PHPT and are associated with the severity of the disease. Impaired renal function is also common in PHPT, but renal function was not associated with renal calcifications.

Secondary hyperparathyroidism among Nigerians with chronic kidney disease.

Secondary hyperparathyroidism (SHPT) is a manifestation of chronic kidney disease mineral bone disorder (CKD-MBD). SHPT is common in patients with chronic kidney disease (CKD) and is associated with significant morbidity and mortality. A cross- sectional descriptive study involving 230 patients with CKD. The mean age of the study population was 44.17±15.24 years. The median intact parathyroid hormone and alkaline phosphatase levels were 96pg/ml (range 4-953pg/ml) and 88 iu/l (range 10-800 iu/l) respectively. The mean (with standard deviation) calcium, serum phosphate, calcium phosphate product and haemoglobin levels were 2.22±0.29mmol/l, 1.8±0.62mmol/l, 3.94±1.42mmol2/l2 and 9.90±1.87g/dl respectively. Majority of patients had advanced CKD with 70.3% of patients in stage G5. The prevalence rates of SHPT, hypocalcaemia, hyperphosphataemia, elevated alkaline phosphatase and elevated calcium phosphate product were 55.2%, 34.8%, 66.1%, 42.2% and 25.2% respectively.Univariate analysis revealed that SHPT was associated with hypocalcaemia, hyperphosphataemia, elevated alkaline phosphatase, proteinuria, anaemia, hypertension, left ventricular hypertrophy and stage of kidney disease; being worse with advancing kidney disease. Independently associated with SHPT were hypocalcaemia (OR=4.84), hyperphosphataemia (OR=3.06), and elevated alkaline phosphatase (OR=2.04). The prevalence of SHPT in CKD is high, occurs early and is independently associated with hypocalcaemia, hyperphosphataemia and elevated alkaline phosphatase. The prevalence of SHPT also increases with worsening renal function.

Interaction of calcium, phosphorus and natural organic matter in electrochemical recovery of phosphate

To address the issues of eutrophication and the potential risk of phosphorus (P) shortage, it is essential to remove and recover P from P-containing streams to close this nutrient cycle. Electrochemical induced calcium phosphate (CaP) precipitation was shown to be an efficient method for P recovery. However, the influence of natural organic matter (NOM) is not known for this treatment. In this paper, the behavior of NOM and its effect on CaP precipitation was studied. In contrast to studies where NOM hindered CaP precipitation, results show that the interaction of NOM with CaP improves the removal of P, independent of the types of NOM. The P removal at the average increased from 43.8 ± 4.9% to 58.5 ± 1.2% in the presence of 1.0 mg L−1 NOM. Based on the yellow color of the CaP product, NOM is co-precipitated. The bulk solution pH with and without buffers has totally different effects on the precipitation process. Without buffer, CaP precipitates on the cathode surface in a wide pH range (pH 4.0–10.0). However, the precipitation process is completely inhibited when the bulk solution is buffered at pH 4.0 and 6.0. This is probably due to neutralization of OH− by the buffers. Regardless of the presence or absence of NOM and solution pH, the recovered products are mainly amorphous CaP unless the electrolysis time was increased to seven days with 4.0 A m−2, in which crystalline CaP formed. These findings advance our understanding on the interaction of Ca, P and NOM species for the application of electrochemical method for P recovery from real wastewater.

Postmenopausal Calcium and Vitamin D Supplements Controversy: Do They Increase Cardiovascular Risk?

Calcium and vitamin D are prescribed in women with osteopenia-osteoporosis to prevent fractures. These bone events increase morbidity and mortality justifying therapy to prevent bone loss. These elderly patients also have cardiovascular risk factors, atherosclerosis and vascular calcifications. Multiple trials demonstrated a relationship between the latter, coronary events and cardiovascular mortality. In these patients, ectopic tissue mineralization may worsen cardiovascular outcome. Calcium intake correlates neither with serum calcium, vascular calcification nor cardiovascular events. However serum calcium-phosphate product is related to vascular calcification and outcome. The main cause for vascular calcification is systemic inflammation and local atherosclerotic process with specific interactions between macrophages and smooth muscle cells. This review examines calcium intake, serum calcium concentration, systemic and vascular inflammation, the mechanisms of vascular calcification and their impact on cardiovascular outcome.

CALCIDIOL IN CHILDREN WITH CHRONIC KIDNEY DISEASE STAGES 2–5

Vitamin D deficiency is characteristic for patients with chronic kidney disease (CKD). THE AIM: to study the prevalence of deficits of calcidiol in children with CKD, and to establish correlations with parathyroid hormone and other markers of bone mineral metabolism in children. PATIENTS AND METHODS. In the period from September 2015 to December 2016 we examined of calcidiol in 53 boys and 32 girls with CKD stages 2-5. The average age of the patients was 11.3+4,7 years. RESULTS. 92.5% of cases in children with CKD revealed a low level of calcidiol. Of them, 30.6% of children were in deficit of vitamin D. The incidence of vitamin D deficiency correlated with a decrease in glomerular filtration rate (r = 0.31; p&lt;0.05). We identified an inverse relationship between calcidiol levels and serum parathyroid hormone, and calcium-phosphorous product (r= -0,29, and r= -0,31; p&gt;&lt;0.05, respectively). Predictors of vitamin D deficiency may be hypoalbuminemia and hyperphosphaturia. CONCLUSION. Determination of vitamin D in children with CKD is extremely important for timely correction and prevention of the development of secondary hyperparathyroidism. Just started the correction of bone and mineral metabolism will improve the quality of life for children with CKD and prevent the development of such complications of hyperparathyroidism as bone deformation and vessels calcification. Keywords: CKD, vitamin D, parathyroid hormone, calcium x phosphorous product&gt;&lt; 0.05). We identified an inverse relationship between calcidiol levels and serum parathyroid hormone, and calcium-phosphorous product (r= -0,29, and r= -0,31; p&lt; 0.05, respectively). Predictors of vitamin D deficiency may be hypoalbuminemia and hyperphosphaturia. CONCLUSION. Determination of vitamin D in children with CKD is extremely important for timely correction and prevention of the development of secondary hyperparathyroidism. Just started the correction of bone and mineral metabolism will improve the quality of life for children with CKD and prevent the development of such complications of hyperparathyroidism as bone deformation and vessels calcification.

Effects of education on low-phosphate diet and phosphate binder intake to control serum phosphate among maintenance hemodialysis patients: A randomized controlled trial.

BackgroundFor phosphate control, patient education is essential due to the limited clearance of phosphate by dialysis. However, well-designed randomized controlled trials about dietary and phosphate binder education have been scarce.MethodsWe enrolled maintenance hemodialysis patients and randomized them into an education group (n = 48) or a control group (n = 22). We assessed the patients’ drug compliance and their knowledge about the phosphate binder using a questionnaire.ResultsThe primary goal was to increase the number of patients who reached a calcium-phosphorus product of lower than 55. In the education group, 36 (75.0%) patients achieved the primary goal, as compared with 16 (72.7%) in the control group (P = 0.430). The education increased the proportion of patients who properly took the phosphate binder (22.9% vs. 3.5%, P = 0.087), but not to statistical significance. Education did not affect the amount of dietary phosphate intake per body weight (education vs. control: −1.18 ± 3.54 vs. −0.88 ± 2.04 mg/kg, P = 0.851). However, the dietary phosphate-to-protein ratio tended to be lower in the education group (−0.64 ± 2.04 vs. 0.65 ± 3.55, P = 0.193). The education on phosphate restriction affected neither the Patient-Generated Subjective Global Assessment score (0.17 ± 4.58 vs. −0.86 ± 3.86, P = 0.363) nor the level of dietary protein intake (−0.03 ± 0.33 vs. −0.09 ± 0.18, P = 0.569).ConclusionEducation did not affect the calcium-phosphate product. Education on the proper timing of phosphate binder intake and the dietary phosphate-to-protein ratio showed marginal efficacy.

Efficacy and safety of long-term management of patients with chronic post-surgical hypoparathyroidism.

To evaluate adherence to European Society of Endocrinology guidelines and risk of renal complications in patients with chronic post-operative hypoparathyroidism (PO-HypoPT) treated with calcium and activated vitamin D metabolites. We evaluated 90 adult patients (68 females and 22 males) with chronic (3years) PO-HypoPT. Total albumin-corrected (Alb-Ca) and ionized serum calcium, phosphate, creatinine, PTH, and 24-h urinary calcium were measured; renal ultrasound was also performed. Healthy hospital employers (n = 142) were used as control. Complete data were available in 82 patients. Twenty-eight (34.1%) met four targets (Alb-Ca, phosphate, calcium phosphate product and 24-h urinary calcium), 36 (43.9%) three, 17 (20.7%) two, and 1 (1.2%) one. Thirteen (14.4%) had Alb-Ca value below and 18 (20.0%) above the target range and 54.9% 24-h urinary calcium above the upper normal limit. Seven (7.7%) has increased serum phosphate and none an increased calcium phosphate product. Eleven (12.2%) patients had eGFR < 60mL/min×1.73m2. Nephrolithiasis was present in 27 (30%) patients. Compared with the controls, patients had lower Alb-Ca (8.9 ± 0.5 vs. 9.5 ± 0.3mg/dL, P 0.0001) and a higher rate of kidney stones, mostly asymptomatic [27/90 (30%) vs 7/142 (5%), P < 0.0001, odd ratio 8.2 (3.4-19.9)]. Fifty-seven patients had ≥ four serum Ca2+ determinations during follow-up. Forty (70.2) patients had values within the target range in > 50% of cases, 18 in > 75%, and only 2 in 100%. Two patients never had values in the target range. Treatment of chronic PO-HypoPT with calcium and activated vitamin D metabolites is suboptimal and associated with an increased risk of renal complications.