INTRODUCTION Pentraxin3 (PTX3) play an important role in the inflammatory response, taking part in recognizing pathogens and damaged tissues. OBJECTIVES The aim of the study was to assess the relationship between PTX3 levels and all-cause and cardiovascular (CV) mortality in chronic kidney disease (CKD) patients during five-year observation period. PATIENTS AND METHODS The study comprised 78 patients (51 hemodialyzed, 27 predialysis). The examined parameters included PTX3, calcium, phosphate, iPTH, interleukin-6 (IL-6), fibroblast growth factor 23 (FGF-23), osteopontin (OPN), osteoprotegerin (OPG), osteocalcin (OC), osteopontin (OPN), osteoprotegerin (OPG), osteocalcin, tumor necrosis factor receptor II (TNF-R II), transforming growth factor-β (TGF-β), hepatocyte growth factor (HGF), stromal cell-derived factor α (SDF1α), and thrombomodulin (TM). In a subgroup of 45 patients, fragments of radial artery obtained during creation of hemodialysis access were stained for calcifications. In 51 patients, ultrasonography was performed to assess intima-media thickness (CCA-IMT). RESULTS Median serum concentration of PTX3 was 1.43 (0.74-2.50) ng/ml. Higher concentrations of fibrinogen, CRP, IL-6, TNF-R II, TGFβ1, HGF, OPN, OPG, FGF-23, TM, SDF1α, lower albumin and uric acid levels were observed in patients with PTX3 above the median. During follow-up, 27 patients (35%) died, including 25 due to CV causes. In contrast to CRP, baseline PTX3 predicted CV mortality independently of classical CV risk factors. Also, PTX3 concentrations significantly predicted mortality after adjustment for age, baseline dialysis status, serum OPG and CRP, radial artery calcifications, and CCA-IMT. CONCLUSIONS We postulate that PTX3 might be an early marker of CV mortality in patients with advanced CKD yet before the increase of specific marker for systemic inflammation like hsCRP.

Macrophages have established roles supporting bone formation. Despite their professional phagocytic nature, the role of macrophage phagocytosis in bone homeostasis is not well understood. Interestingly, apoptosis is a pivotal feature of cellular regulation and the primary fate of osteoblasts is apoptosis. Efferocytosis (phagocytosis of apoptotic cells) is a key physiologic process for the homeostasis of many tissues, and is associated with expression of osteoinductive factors. To test effects of macrophage depletion and compromised phagocytosis on bone, 16-week-old male C57BL/6J mice were treated with trabectedin-a chemotherapeutic with established anti-macrophage effects. Trabectedin treatment reduced F4/80+ and CD68+ macrophages in the bone marrow as assessed by flow cytometry, osteal macrophages near the bone surface, and macrophage viability in vitro. Trabectedin treatment significantly reduced marrow gene expression of key phagocytic factors (Mfge8, Mrc1), and macrophages from treated mice had a reduced ability to phagocytose apoptotic mimicry beads. Macrophages cultured in vitro and treated with trabectedin displayed reduced efferocytosis of apoptotic osteoblasts. Moreover, efferocytosis increased macrophage osteoinductive TGF-β production and this increase was inhibited by trabectedin. Long-term (6-week) treatment of 16-week-old C57BL/6J mice with trabectedin significantly reduced trabecular BV/TV and cortical BMD. Although trabectedin reduced osteoclast numbers in vitro, osteoclast surface in vivo was not altered. Trabectedin treatment reduced serum P1NP as well as MS/BS and BFR/BS, and inhibited mineralization and Runx2 gene expression of osteoblast cultures. Finally, intermittent PTH 1-34 (iPTH) treatment was administered in combination with trabectedin, and iPTH increased trabecular bone volume fraction (BV/TV) in trabectedin-treated mice. Collectively, the data support a model whereby trabectedin significantly reduces bone mass due to compromised macrophages and efferocytosis, but also due to direct effects on osteoblasts. This data has immediate clinical relevance in light of increasing use of trabectedin in oncology. © 2017 American Society for Bone and Mineral Research.

OBJECTIVE

To examine the prevalence and risk factors for hypercalcemia among non-dialysis chronic kidney disease (CKD) patients with mineral and bone disorder (MBD).

METHODS

A retrospective cohort study was conducted in Singapore General Hospital, involving all CKD stage 4 and 5 pre-dialysis patients who were on treatment for MBD in June 2016. Each patient was followed up for 1 year and screened for hypercalcemia episodes. Mild, moderate and severe hypercalcemia were defined as corrected calcium of 2.47-3.00, 3.01-3.50 and ≥ 3.51 mmol/l respectively. Patients who were on dialysis, post-renal transplant, post-parathyroidectomy or had no calcium levels taken during the study period were excluded. Details related to patients' clinical information and hypercalcemia episodes were collected. Multivariate logistic regression analysis was performed to evaluate risk factors for hypercalcemia.

RESULTS

Of 557 patients, 75 (13.4%) patients developed hypercalcemia. There were 120 (97.6%) mild and 3 (2.4%) moderate hypercalcemia episodes. The daily elemental calcium intake from phosphate binders and usage of vitamin D analogues did not differ between patients with and without hypercalcemia (p>> 0.05). After adjusting for covariates, lower baseline iPTH level [odds ratio (OR) 0.96, 95% CI 0.93-0.99], history of hypercalcemia in past 1 year (OR 11.11, 95% CI 3.36-36.75) and immobility (OR 3.34, 95% CI 1.34-8.40) were associated with increased hypercalcemia risk.

CONCLUSIONS

Hypercalcemia affects a significant proportion of pre-dialysis patients with MBD. More studies should be undertaken to evaluate other risk factors associated with hypercalcemia.

Intermittent parathyroid hormone (iPTH) treatment induces bone anabolic effects that result in the recovery of osteoporotic bone loss. Human PTH is usually given to osteoporotic patients because it induces osteoblastogenesis. However, the mechanism by which PTH stimulates the expansion of stromal cell populations and their maturation toward the osteoblastic cell lineage has not be elucidated. Mouse genetic lineage tracing revealed that iPTH treatment induced osteoblastic differentiation of bone marrow (BM) mesenchymal stem and progenitor cells (MSPCs), which carried the leptin receptor (LepR)-Cre. Although these findings suggested that part of the PTH-induced bone anabolic action is exerted because of osteoblastic commitment of MSPCs, little is known about the in vivo mechanistic details of these processes. Here, we showed that LepR⁺ MSPCs differentiated into type I collagen (Col1)⁺ mature osteoblasts in response to iPTH treatment. Along with osteoblastogenesis, the number of Col1⁺ mature osteoblasts increased around the bone surface, although most of them were characterized as quiescent cells. However, the number of LepR-Cre-marked lineage cells in a proliferative state also increased in the vicinity of bone tissue after iPTH treatment. The expression levels of SP7/osterix (Osx) and Col1, which are markers for osteoblasts, were also increased in the LepR⁺ MSPCs population in response to iPTH treatment. In contrast, the expression levels of Cebpb, Pparg, and Zfp467, which are adipocyte markers, decreased in this population. Consistent with these results, iPTH treatment inhibited 5-fluorouracil- or ovariectomy (OVX)-induced LepR⁺ MSPC-derived adipogenesis in BM and increased LepR⁺ MSPC-derived osteoblasts, even under the adipocyte-induced conditions. Treatment of OVX rats with iPTH significantly affected the osteoporotic bone tissue and expansion of the BM adipose tissue. These results indicated that iPTH treatment induced transient proliferation of the LepR⁺ MSPCs and skewed their lineage differentiation from adipocytes toward osteoblasts, resulting in an expanded, quiescent, and mature osteoblast population. © 2019 American Society for Bone and Mineral Research.

Mineral and bone disorders frequently cause cardiovascular complications and mortality in hemodialysis patients, but few observational studies of Japanese patients have investigated this matter. A retrospective cohort study of 99 patients (53 males, 46 females; mean age: 65 +/- 12 year; 38% with diabetes mellitus) on maintenance hemodialysis in our dialysis center was conducted. Mean serum Ca, P and intact parathyroid hormone (iPTH) levels were 9.2 +/- 0.9 mg/dL, 6.1 +/- 1.7 mg/dL, and 233 +/- 333 pg/mL, respectively. The cutoff values for each of these three parameter were defined according to the target ranges recommended by the Japanese Society for Dialysis Therapy (JSDT) guidelines (Ca: 8.4-10.0 mg/dL; P: 3.5-6.0 mg/dL; iPTH: 60-180 pg/mL). During a 45-month follow up, patients with all parameters outside the target ranges showed the highest incidence of cardiovascular events and all-cause deaths (16.6 and 29.2 per 1000 person-years, respectively). The relative risks of cardiovascular events and all-cause deaths were analyzed by multivariate Cox regression models. The hazard ratio (HR) for cardiovascular events was significantly lower for patients who achieved serum Ca and P objectives compared with others (HR: 2.12; 95% CI: 1.04-4.34; P < 0.05), and similar differences were observed for all-cause deaths (HR: 3.10; 95% CI: 1.13-8.53; P < 0.05). However, the relationship between iPTH levels and each of the endpoints was less pronounced. The results of this study provide support for the JSDT guidelines, which give priority to the control of serum Ca and P levels over the control of parathyroid function.

BACKGROUND

Poor medication adherence is a frequent cause of treatment failure but is difficult to diagnose. In this study we have evaluated the impact of measuring adherence to cinacalcet-HCl and phosphate binders in dialysis patients with uncontrolled secondary hyperparathyroidism.

METHODS

7 chronic dialysis patients with iPTH-levels>>= 300 pg/ml despite treatment with>>= 60 mg cinacalcet-HCl were included. Medication adherence was measured using the "Medication Events Monitoring System" during 3 months, followed by another 3-month period without monitoring. The adherence results were monthly discussed with the patients, as well as strategies to improve them.

RESULTS

During monitoring, the percentage of prescribed doses taken was higher for cinacalcet-HCl (87.4%) and sevelamer (86.3%) than for calcium acetate (76.1%), as was the taking adherence (81.9% vs. 57.3% vs. 49.1%) but not the percentage of drug holidays (12.3% vs. 4.5% vs. 3.6%). Mean PO4 levels (from 2.24 +/- 0.6 mmol/l to 1.73 +/- 0.41 mmol/l; p = 0.14) and Ca++ x PO4 product (4.73 +/- 1.43 to 3.41 +/- 1.04 mmol2/l2; p = 0.12) improved and iPTH-level improved significantly from 916 +/- 618 pg/ml to 442 +/- 326 pg/ml (p = 0.04), without any change in medication. However, as drug monitoring was interrupted, all laboratory parameters worsened again.

CONCLUSIONS

Assessment of drug adherence helped to document episodes of non-compliance and helped to avoid seemingly necessary dose increases.

OBJECTIVE

Uremic hyperparathyroidism (UHPT) has been shown to contribute to the development and progression of chronic kidney disease-mineral bone disorder. UHPT is frequently observed in chronic dialysis patients, and patients with UHPT are associated with increased risk of all-cause and cardiovascular mortality. Cinacalcet is a novel agent that increases sensitivity to the calcium-sensing receptor and is approved for control of UHPT. Nevertheless, cinacalcet is costly and information regarding efficacy of low-dose cinacalcet on UHPT is limited.

METHODS

We conducted a retrospective study to evaluate treatment with either low-dose calcitriol combined with low-dose cinacalcet (25 mg) (d-cinacalcet) or calcitriol alone (VitD) in dialysis patients with moderate to severe UHPT. A total of 81 dialysis patients were enrolled (40 subjects in d-cinacalcet group and 41 subjects in VitD group). Demographic data including age, gender, duration on dialysis and biochemical data were reviewed and recorded.

RESULTS

At the end of the study, the intact parathyroid hormone (iPTH) levels of the d-cinacalcet group declined significantly (from 1166.0 ± 469.3 pg/mL to 679.8 ± 421.6 pg/mL, p < 0.0001), while there was no significant change in the VitD group. Significant decrease of serum calcium (Ca: 9.9 ± 0.6 mg/dL vs. 9.6 ± 0.8 mg/dL, p = 0.002), phosphorus (P: 5.9 ± 1.3 mg/dL vs. 4.9 ± 0.9 mg/dL, p < 0.0001) and calcium phosphate product (Ca × P: 58.7 ± 15.0 mg2/dL2 vs. 46.9 ± 8.9 mg2/dL2, p < 0.0001) were observed in the d-cinacalcet group. In addition, the subjects in the d-cinacalcet group had a greater proportion to achieve Kidney Disease Outcomes Quality Initiative (KDOQI)-recommended biochemical targets than the subjects in the VitD group (Ca: 48% vs. 24%; P: 78% vs. 32%; Ca × P: 85% vs. 37%; iPTH: 15% vs. 0%).

CONCLUSIONS

We conclude that combination therapy of low-dose cinacalcet and calcitriol is more effective than calcitriol alone as a treatment for moderate and severe UHPT in chronic dialysis patients. Furthermore, this therapy is associated with improvement in hyperphosphatemia and hypercalcemia.

Secondary hyperparathyroidism (SHPT) is a common complication in chronic renal disease. Osteoprotegerin (OPG), an extracellular cytokine receptor secreted by osteoblasts, can promote bone formation by inhibiting the function of osteoclasts. Hemodialysis (HD) patients have elevated serum OPG levels. OPG secretion can be suppressed with high parathyroid hormone (PTH) levels. HD patients with refractory SHPT can benefit from parathyroidectomy (PTX) treatment, but the changes of serum OPG, bone turnover markers and bone mineral density (BMD) following PTX in HD patients remain unclear. In this study, patients on maintenance HD who received PTX for refractory SHPT (n = 28) were prospectively followed for 1 year. Serum intact PTH (iPTH), alkaline phosphatase (Alk-P), and OPG were measured serially; BMD was measured pre-PTX and at 1 year after PTX. After PTX, serum iPTH levels reduced profoundly. Serum Alk-P levels increased rapidly, peaking at 2 weeks post-PTX, while serum OPG levels gradually increased at 2 weeks after PTX and peaked at 2 months. BMD improved in both femoral neck (FN; cancellous and cortical bone) and lumbar spine (LS; cancellous bone). Higher baseline iPTH levels were associated with greater FN and LS BMD improvements at one year after PTX. The increment of serum OPG was correlated with the increase in LS BMD, implying that inhibition of osteoclastic bone resorption may improve BMD within the first year after PTX. These findings suggest that PTX removes the suppressive effects of high PTH on OPG secretion, resulting in the increased serum OPG levels that may contribute to BMD improvement.

BACKGROUND

To identify differences between the effects of calcitriol and the calcitriol analogue, maxacalcitol, on parathyroid hormone (PTH) and bone metabolisms, we conducted a randomized prospective multicentre study on patients on chronic haemodialysis.

METHODS

We randomly assigned 91 patients with secondary hyperparathyroidism [intact PTH (iPTH)>> or =150 pg/ml] to have either calcitriol (47 patients) or maxacalcitol (44 patients) therapy, for 12 months after a 1 month control period. Serum electrolytes, bone alkaline phosphatase (bAP), iPTH, total PTH and PTH(1-84) (whole PTH) levels were measured periodically. The first end point was a serum iPTH of <150 pg/ml, the second was the iPTH levels obtained.

RESULTS

Treatment was discontinued for various reasons in nine patients in each group, but no serious side effects were observed in either group. The numbers of cases reaching the first end point were not significantly different between the two groups. Serum calcium concentration was significantly higher in the maxacalcitol than the calcitriol group during early treatment, but not at the end of treatment. Throughout the treatment period there were no significant differences between the two groups in serum iPTH, inorganic phosphate, the product of the serum calcium and inorganic phosphorus concentrations, bAP, or the ratio of whole PTH to total PTH minus whole PTH. Nor were the changes in these parameters significantly different between the two groups comparing the patients with moderate to severe hyperparathyroidism (basal iPTH>> or =500 pg/ml).

CONCLUSIONS

Calcitriol and maxacalcitol are equally effective on PTH and bone metabolism.

BACKGROUND

The relationship between parathyroid function, an important determinant of bone turnover, and bone mineral density (BMD) in patients with chronic kidney disease is not fully understood. We wanted to analyze the association between BMD and parathyroid function in hemodialysis patients in details.

METHODS

In a cross-sectional design, data from 270 patients (age 55 ± 15 years, 60% men, all Caucasian) on maintenance hemodialysis were analyzed. All patients underwent dual energy X-ray absorptiometry of the lumbar spine (LS), femoral neck (FN) and distal radius (DR). In addition to routine laboratory tests, blood samples were collected for iPTH, serum markers of bone metabolism (alkaline phosphatase, type I collagen crosslinked-C-telopeptide) and 25OH vitamin D.

RESULTS

Based on Z-scores, bone mineral density was moderately reduced only at the femoral neck in the total cohort. The average Z-score of the "low PTH" group (iPTH < 100 pg/ml) was not different from the Z-score of patients with iPTH in the "target range" (100-300 pg/ml) at any measurement site. While iPTH was negatively correlated with BMD at all measurement sites in patients with iPTH>> 100 pg/ml (rho = -0.255, -0.278 and -0.251 for LS, FN and DR, respectively, P < 0.001 for all), BMD was independent of iPTH in patients with iPTH < 100 pg/ml. Furthermore, iPTH was not associated with serum markers of bone metabolism, but these markers were negatively correlated with BMD in the "low PTH" group.

CONCLUSIONS

Low PTH levels are not associated with low BMD in patients with end-stage kidney disease. Furthermore, bone metabolism seems to be independent of iPTH in patients with relative hypoparathyroidism likely reflecting skeletal resistance to PTH.

BACKGROUND

Both fetuin-A and hyperparathyroidism play crucial roles in vascular calcification (VC) and bone metabolism. However, the correlation between secondary hyperparathyroidism (SHPT), parathyroidectomy (PTX) and fetuin-A levels in dialysis patients has not yet been studied.

METHODS

For this study, we included 27 consecutive dialysis patients with severe SHPT who underwent total PTX with autotransplantation over a period of 2 years (from Oct 2006 to Sep 2008). Serum ionized calcium (iCa), phosphorus (Pi), bone-specific alkaline phosphatase (bAP), intact parathyroid hormone (iPTH), and fetuin-A were checked basally and 2, 7, 14, 30, and 60 days after PTX.

RESULTS

Two days after PTX, the iPTH, serum iCa, and Pi concentrations significantly decreased. Serum bAP levels gradually increased after PTX, peaked after 14 days (p < 0.05), and then gradually decreased. Serum fetuin-A levels significantly increased during the first 7 days after PTX, peaked 14 days after PTX (0.21 ± 0.05 vs. 0.35 ± 0.07 mg/ml, p < 0.05), and then remained at a stable level 60 days after PTX. There were significant correlations between percentage increase in serum fetuin-A levels and percentage decrease in serum iPTH levels 2 days and 7 days after PTX (r = 0.526, p < 0.01; r = 0.403, p < 0.05, respectively) and correlations between percentage increase in serum fetuin-A levels and percentage decrease in serum iCa levels 30 and 60 days after PTX (r = 0.449, p < 0.05; r = 0.474, p < 0.05, respectively).

CONCLUSIONS

Serum fetuin-A significantly increased after PTX in uremic patients with SHPT. The percentage increase in serum fetuin-A after PTX was closely correlated with the percentage decrease in serum iPTH levels immediately after PTX, and with the percentage decrease in serum iCa levels in the later stage after PTX. Further investigations are necessary to further understand the regulation of fetuin-A in dialysis patients with sSHPT.

BACKGROUND

Low bone mass is common in end-stage renal disease patients, especially those undergoing hemodialysis. It can lead to serious bone health problems such as fragility fractures. The purpose of this study is to investigate the risk factors of low bone mass in the hemodialysis patients.

METHODS

Sixty-three subjects on hemodialysis for at least 6 months were recruited from a single center for this cross-sectional study. We collected data by questionnaire survey and medical records review. All subjects underwent a bone mineral density (BMD) assay with dual-energy x-ray absorptiometry at the lumbar spine and right hip. Data were statistically analyzed by means of descriptive analysis, independent t test and one way analysis of variance for continuous variables, Pearson product-moment correlation to explore the correlated factors of BMD, and stepwise multiple linear regression to identify the predictors of low bone mass.

RESULTS

Using WHO criteria as a cutoff point, fifty-one subjects (81%) had a T-score lower than -1, of them 8 subjects (13%) had osteoporosis with the femoral neck most commonly affected. Regarding risk factors, age, serum alkaline phosphatase (ALP) level, and intact parathyroid hormone (iPTH) level had significant negative correlations with the femoral neck and lumbar spine BMD. On the other hand, serum albumin level, effective exercise time, and body weight (BW) had significant positive correlations with the femoral neck and lumbar spine BMD. Age, effective exercise time, and serum albumin level significantly predicted the femoral neck BMD (R(2) x 0.25), whereas BW and the ALP level significantly predicted the lumbar spine BMD (R(2) x 0.20).

CONCLUSIONS

This study showed that advanced age, low BW, low serum albumin level, and high ALP and iPTH levels were associated with a low bone mass in the hemodialysis patients. We suggest that regular monitoring of the femoral neck BMD, maintaining an adequate serum albumin level and BW, and undertaking an exercise program are important to improve bone health in the patients undergoing hemodialysis.

BACKGROUND

A persistent hyperphosphataemia represents one of the most important factors in the development of secondary hyperparathyroidism (sHPTH). The present prospective study was designed in order to test the hypothesis that a higher body mass index (BMI) may predispose to a larger body burden of phosphate (P), influencing by that way the severity of sHPTH.

METHODS

Histological studies were performed on 168 parathyroid glands of 42 consecutive adult Caucasian haemodialysis patients (20 males and 22 females) referred for first parathyroidectomy (PTx): each parathyroid gland was graded as 0, when only or mainly diffuse hyperplasia was found, or as 1, when only or mainly nodular hyperplasia was found. Thus, parathyroid histology was scored on a 5-point scale: 0 = diffuse hyperplasia in the four glands; 1 = nodular hyperplasia in one gland; 2 = nodular hyperplasia in two glands; 3 = nodular hyperplasia in three glands; 4 = nodular hyperplasia in the four glands. For sake of simplicity, the three less severe histological gradings, i.e. scores 0-2 were grouped together and indicated as score group 2.

RESULTS

The distribution of the patients was the following: 28.6% were in the score group 2, 23.8% in the score group 3 and 47.6% in the score group 4 (20 patients, 14 of whom were females). The output of the one-way ANOVA with the histological scores as grouping variable and age, dialysis duration, BMI and pre-PTx serum iPTH, alkaline phosphatase (ALP), calcium (Ca) and P as predictors showed that only BMI was different among the three histological scores (P = 0.001). By stratifying the analysis by gender, the relationship between BMI and histological scores was confirmed only in females (P = 0.006). The stratification of the entire cohort into two groups according to the cut-off value of BMI = 25 kg/m(2) showed that: (i) score 4 was more prevalent in the high-BMI group and score 2 in the normal-BMI group (P = 0.01); (ii) female gender was more represented in the high-BMI group (12 out of 18 patients, P = 0.04); and (iii) the pre-PTx serum P levels were significantly higher in the high-BMI group (P = 0.008). The output of the linear multiple regression analysis with pre-PTx serum P as dependent variable and BMI, pre-PTx serum ALP and Ca as independent variables (selected according to the statistical significance in the bivariate correlations) showed that only serum Ca and BMI were statistically significant predictors of serum P levels.

CONCLUSIONS

A high BMI and female gender are associated with an increased risk of nodular hyperplasia of parathyroid glands in adult Caucasian haemodialysis patients. The two risk factors, above all if combined in the same patient, appear to predispose to a larger body burden of P, increasing by that way the severity of sHPTH.

BACKGROUND

The incidence of diabetic nephropathy (DN) increases year by year. However, clinical characteristics of DN patients on maintenance hemodialysis (MHD) were rarely reported in China. The purpose of this study was to examine the clinical characteristics of the DN patients on MHD in Anhui Province, Eastern China.

METHODS

The clinical data of MHD patients in the hemodialysis centers of 26 hospitals in Anhui Province from January 1, 2014, to March 31, 2014, were examined. The differences between DN patients and non-DN patients were compared regarding vascular access, nutritional status, mineral and bone disorder, and other indexes.

RESULTS

Among the selected 2768 adult MHD patients, 427 had DN. The incidence of hypertension, coronary heart disease, and cerebral thrombus in DN patients was 94.1%, 21.5%, and 15.0%, respectively, which were higher than those in non-DN patients (P < 0.001). Category of vascular access for hemodialysis in DN patients was arteriovenous fistula (AVF) (87.4% [373/427]) and tunneled cuffed catheter (TCC) (11.2% [48/427]). The percentage of AVF was significantly lower than that of non-DN patients (P < 0.001), and percentage of TCC was significantly higher than that of non-DN patients (P < 0.001). Hemoglobin achievement rate in DN patients was 32.0%. The incidence of hypoalbuminemia was 24.7%, significantly higher than that in non-DN patients (P < 0.001). The achievement rate of the target range in mineral values was 55.9% in corrected serum calcium level, 30.1% in serum phosphorus level, and 49.3% in intact parathyroid hormone (iPTH) level in DN patients. Compared with non-DN patients, the achievement rate of serum phosphorus was significantly higher in DN patients.

CONCLUSIONS

DN patients on MHD in Anhui province exhibited different clinical characteristics compared to non-DN hemodialysis patients. They presented higher percentage in TCC use and cardiovascular complication, lower serum albumin and iPTH levels than those in non-DN patients.

One of the factors involved in accelerated atherosclerosis in hemodialysis patients is dyslipidemia. In this study we considered factors involved in intensification of dyslipidemia in hemodialysis patients. This study was done on 36 maintenance hemodialysis patients. Serum lipoprotein (a), Triglyceride, Cholesterol, HDL-C,LDL-C and also serum Intact parathormone(iPTH), Calcium, Phosphorus, Magnesium were measured. In statistical analysis there was not any correlation between serum lipids and iPTH. There was not correlation between serum calcium with serum lipids (p>> 0.05). There was not correlation between CaxP product with serum lipids (p>> 0.05). There was a positive correlation between serum Magnesium and Lipoprotein(a) (P < 0.05) and also positive correlation between serum magnesium with triglyceride level (P < 0.05) was seen too. Magnesium doesn't increase the lipoprotein synthesis. It may involve in the regulation of some enzymes responsible for lipoprotein synthesis. Correlation of serum magnesium with serum triglycerides can be due to changes in hepatic triglyceride metabolism. Lipoprotein(a) is a non traditional factor of premature atherosclerosis, its association with serum magnesium needs more attention in hemodialysis patients.

Heart rate variability (HRV) is a non-invasive method used for the assessement of autonomic modulation of heart rate. Decreased HRV is an indicator of increased cardiovascular risk. The aim of this study was to evaluate the relationship between the heart rate variability and left ventricular hypertrophy and native parathormone (iPTH) serum concentration in patients with chronic renal failure (crf) treated by hemodialysis. 24-hours ECG recording with time domain HRV evaluation, resting, transthoracic echocardiography (ECHO), were measured in 59 crf patients and in 30 healthy volunteers. Creatinine, urea, total protein, albumin, electrolytes, hemoglobin, hematocrite and iPTH serum concentration as well as body mass index (BMI) were assessed in all patients. All crf patients had decreased lower values of HRV. The correlations between SDNN, pNN50, rMSSD and parameters of LVH and with PTH serum level indicated the disturbances of the autonomic function in chronic renal patients. Left ventricular hypertrophy (LVH) in all crf patients was observed. The correlations between iPTH serum level and parameters of LVH suggest the role of PTH in the development of uremic cardiomyopathy.

Vitamin D derivatives correct high bone remodeling by decreasing plasma iPTH concentration in uremic patients with secondary hyperparathyroidism. However, without bone biopsy, plasma iPTH alone might not provide sufficient information regarding vitamin D-induced bone changes. Plasma bone-specific alkaline phosphatase (bAP) seems more sensitive than iPTH in assessing the degree of bone remodeling. We prospectively studied the evolution of iPTH and bAP in 14 adult hemodialysis patients treated for 1 year by i.v. alfacalcidol pulses. The mean total alfacalcidol dose was 0.08 +/- 0.02 g/kg/week. Ten patients completed the study, 2 patients had to be parathyroidectomized before week 24 because of hypercalcemia and uncontrolled hyperphosphatemia, and 2 other patients died before week 36. Mean iPTH levels diminished from 826 +/- 300 pg/ml (range 507 - 1,500 pg/ml) at baseline to 436 +/- 371 pg/ml (range 18 - 1,095 pg/ml) after 52 weeks of treatment (48% of decrease). Only 2 patients normalized plasma iPTH levels while 8/10 normalized bAP. Five patients remained with plasma iPTH concentrations higher than 5-fold the normal value. In contrast, plasma bAP levels declined from 47.6 +/- 32.2 ng/ml (range 15.4 - 130.0 ng/ml) at baseline to 17.8 +/- 9.9 ng/ml (range 8.0 +/- 38.0 ng/ml) at week 52 (63% of decrease). Bone histomorphometry was available in 6 patients after 15.8 +/- 5.1 months of alfacalcidol treatment. None of them met the criteria of adynamic bone disease as they had increased bone resorption and marrow bone fibrosis. Bone formation rate was normal in 2 patients and unmeasurable in the other 4. Two patients showed signs of osteomalacia. In conclusion, alfacalcidol preferentially reduced bone formation rate rather than the other histological parameters of secondary hyperparathyroidism. It reduced plasma bAP more efficiently than iPTH.

In long-term haemodialysis patients suffering from secondary hyperparathyroidism Se iPTH could be suppressed by an intravenous calcitriol therapy. As the Se iPTH level became reduced, lower doses of Rh-EPO were already sufficient for the maintenance of the target haematocrit, while in two patients not requiring Rh-EPO treatment an improvement of their moderate anaemia could be observed. These data corroborate the view that calcitriol is an effective drug in secondary hyperparathyroidism. The results suggest that in the improvement of renal anaemia of dialysed patients the reduction of the Se-PTH level also plays a role.

In addition to renal osteodystrophy, postmenopausal women on hemodialysis are at high risk for osteoporosis. Recent studies reported the effects of raloxifene, a selective estrogen receptor modulator for osteoporosis, in postmenopausal women. The present study evaluated the efficacy of raloxifene and its effects on bone mineral metabolism in postmenopausal Japanese patients on dialysis. In a prospective, multicentre study, 17 postmenopausal women on chronic hemodialysis with severe osteoporosis (bone mineral density [BMD]≤2 SD by bone densitometry) were treated with 60 mg/day raloxifene hydrochloride for 12 months. The study also included 10 age-matched control women. Vitamin D and calcium salts were not changed during the study. Intact parathyroid hormone (iPTH), serum calcium and phosphorus, and bone resorption marker (NTx) were measured, and BMD were determined by DEXA, at 0, 6, and 12 months after administration of raloxifene. The mean lumbar spine BMD at baseline was similar in the two groups. Raloxifene therapy (for 12 months) improved lumbar spine BMD (by 2.6%) in 53% of the patients, while 70% of the control group showed a reduction in BMD (by 4.0%). Raloxifene significantly decreased serum calcium and increased iPTH. Our results suggested that raloxifene improved trabecular BMD in postmenopausal Japanese women on hemodialysis. The effects of raloxifene on serum calcium and serum iPTH level suggest it improves bone resorption. Vitamin D and/or calcium salts should be added to raloxifene treatment to avoid secondary hyperparathyroidism.

BACKGROUND

Parathyroidectomy (PTx) is recommended in patients affected by secondary hyperparathyroidism (2HPT) of chronic kidney disease-mineral bone disorders (CKD-MBD), resistant to medical treatment. Analyzing total parathyroidectomy with muscular or subcutaneous autoimplantation (TPai) outcomes in hemodialysis (HD) 2HPT patients, and monitoring intact parathyroid hormone (iPTH) levels, we evaluated long-term functional results of subcutaneous parathyroid glandular tissue autoimplantation.

METHODS

40 HD 2HPT patients, resistant to medical treatment, and awaiting for renal transplantation, underwent total parathyroidectomy with subcutaneous autoimplantation of 9-12 fragments of not nodular hyperplasia parathyroid tissue in not dominant forearm. iPTH were analyzed 24 h, and 3-6-12-24 months after surgery. The 1.08-6.99 pmol/L range was taken as reference of normal iPTH level based on which eu- (1.08-6.99), hypo- (<1.08), aparathyroidism (0) and persistence or relapse (>6.99) of disease were determined.

RESULTS

In every case PTai determined an extraordinary improvement of quality of life, associated with a notable reduction of iPTH serum level. Immediate normalization of iPTH was achieved in 50% of cases; hypoparathyroidism in 25% of cases and persistence of disease in 25% were observed. Long term follow-up showed a reduction of hypoparathyroidism and an increase of relapse rate up to 20%. Grafting resection was never performed.

CONCLUSIONS

Subcutaneous autotrasplantation is a very simple and fast surgical technique. Nevertheless, similar success and recurrence rates were reported following muscular or subcutaneous grafting, as confirmed in our experience.

CONCLUSIONS

Subcutaneous grafting was effective as muscular implantation, with comparable functional results, but avoiding its potential complications.

OBJECTIVE

Refractory hyperparathyroidism is a state of parathyroid hyperfunction and hypercalcaemia in uraemic patients with previous secondary hyperplasia. We studied histopathological features and p53 expression in 49 parathyroid glands of uraemic patients (n = 21) with refractory hyperparathyroidism in order to investigate whether p53 abnormalities could be present in parathyroid hyperplasias of chronic renal failure.

RESULTS

Nodular hyperplasia was found in 77.5% of the glands (n = 38). The proportion of oxyphil cells and acinar cell arrangements was higher in nodular hyperplasia than in diffuse hyperplastic glands P < 0.001). Duration of renal disease and haemodialysis treatment tended to be longer in patients with nodular hyperplasia. There was no correlation between serum intact PTH (iPTH), calcium and hyperplasia pattern. A trend for a higher glandular mass was found in nodular type hyperplasia (1.88 +/- 2.13 g) than in diffuse type hyperplasia (0.87 +/- 1.28 g; P = 0.06). Nuclear p53 immunoreactivity was shown in 55% of the hyperplastic glands, whereas it was not detected in 12 normal parathyroid glands used as controls. p53 staining was present in c. 82% of the diffuse hyperplastic glands and in 47% of the nodular hyperplastic glands (P = 0.08).

CONCLUSIONS

Nodular type hyperplasia was the predominant histopathological pattern in uraemic patients with refractory hyperparathyroidism in our study. Nodular hyperplastic glands characteristically had higher percentage of oxyphil cells, acinar cell arrangements and mass than diffuse hyperplastic glands. A high prevalence of p53 protein expression was found in hyperplastic glands of uraemic patients. Our results suggest that p53 abnormalities might be involved in the pathogenesis of parathyroid hyperplasia in chronic renal failure.

Purpose. Secondary hyperparathyroidism with nodular hyperplasia is resistant to medical therapies. Cinacalcet is an effective treatment for severe secondary hyperparathyroidism. This multicentre retrospective study was designed to determine the long-term efficacy of cinacalcet in patients with nodular hyperplasia, the advanced type of parathyroid hyperplasia. Subjects and methods. The study subjects were 20 haemodialysis patients with secondary hyperparathyroidism. Patients with ultrasonographically confirmed large parathyroid glands (volume >0.5 cm(3)) were considered to have nodular hyperplasia (n = 8). Cinacalcet was started at the dose of 25 mg/day and titrated up to 100 mg/day to achieve the target intact-parathyroid hormone (iPTH) level of <250 pg/ml. Serum iPTH, corrected calcium, serum phosphorus, calcium × phosphorus product were measured and compared over the 48-week period of treatment with cinacalcet in all 20 patients and over 120 weeks in 6 of the patients (2 with nodular hyperplasia and 4 with non-nodular hyperplasia). We also examined the achievement rate of K/DOQI guideline treatment targets. The dosages of vitamin D preparation, sevelamer hydrochloride and calcium- containing phosphate binder were adjusted for the above target values. Results. iPTH levels were significantly lower at 48 weeks in both groups. However, corrected calcium levels, serum phosphorus levels and calcium phosphorus products were within the target values in the non-nodular hyperplasia group (n = 12), while the target value could not be achieved in the nodular hyperplasia group. In the long-term follow-up group, the levels of iPTH, corrected calcium, serum phosphorus and calcium × phosphorus products were significantly higher in nodular hyperplasia than in non-nodular hyperplasia. Conclusion. Our study suggests that cinacalcet lacks long-term efficacy in nodular hyperplasia, especially for controlling serum calcium and phosphorus levels.

BACKGROUND

Cytosolic free calcium ([Ca(2+)](i)) is an important second messenger during stimulation in a wide variety of cells, including polymorphonuclear leukocytes (PMNs). Its mobilization in PMNs is altered in various diseases such as atherosclerosis and ageing. In chronic haemodialysis (HD) patients, both atherosclerosis and accelerated ageing are well known. Therefore [Ca(2+)](i) in resting PMNs of HD patients was determined along with certain parameters which might affect it, such as recombinant human erythropoietin (rHuEpo) treatment, calcium-phosphate balance, and biocompatibility of dialysis membranes.

METHODS

PMNs were separated by density centrifugation and [Ca(2+)](i) was determined by spectrofluorimetry using Quin 2/AM fluorescent dye. Laboratory parameters were determined by standard methods in clinical chemistry.

RESULTS

It was found that [Ca(2+)](i) in resting PMNs of HD patients not undergoing rHuEpo therapy was higher than that of controls. After 12-weeks of rHuEpo therapy, [Ca(2+)](i) decreased to near normal level. The role of erythropoiesis in normalization of [Ca(2+)](i) in resting PMNs was supported by PMN [Ca(2+)](i) which was elevated in patients who had low haemoglobin (<100 g/l) or haematocrit (<0.30) values. In some patients, including those receiving rHuEpo treatment, [Ca(2+)](i) remained high, suggesting a role for other parameters in increasing [Ca(2+)](i). One possible parameter might be the disturbed calcium-phosphate metabolism of chronic renal failure, because we found a strong correlation between [Ca(2+)](i) and plasma iPTH levels in HD patients (r=0.743, P<0.001). [Ca(2+)](i) was also elevated in PMNs of those patients who had either low plasma calcium or high plasma phosphate levels. PMN [Ca(2+)](i) of HD patients correlated positively with the duration of HD (r=0.671, P<0.001). However, there was no correlation between [Ca(2+)](i) and patient age. The dialysis procedure itself also transiently increased PMN [Ca(2+)](i) HD patients, independently of the type of dialysis membrane.

CONCLUSIONS

PMN [Ca(2+)](i) is modulated by various parameters in HD patients, including the degree of anaemia, disturbances of calcium metabolism, and duration of dialysis treatment. The elevated [Ca(2+)](i) of resting PMNs might contribute to altered functions in these cells.

OBJECTIVE

The objective of the study was to determine the situation concerning mineral metabolism and bone disease in hemodialysis (HD) patients living in the community of Valencia (Spain), as well as the clinical practices for bone disease control in relation to the laboratory targets recommended in the National Kidney Foundation Dialysis Outcomes Quality Initiative (K/DOQI) guidelines.

METHODS

In December 2003, a cross-sectional study was performed including 2392 patients (1485 males and 907 females) from 43 different centers in the council of Valencia (the entire HD population). Mean age was 65.8 +/- 14 yrs. Cut-off levels for the study of calcium, phosphorus, calcium-phosphorus product (Ca x P) and parathyroid hormone (PTH) were performed following the recommendations of the K/DOQI guidelines.

RESULTS

The mean values for calcium were 9.57 +/- 0.7 mg/dL, phosphorus 4.97 +/- 1.5 mg/dL, intact PTH (iPTH) 297 +/- 353 pg/mL, Ca x P 47.5 +/- 15 mg2/dL2. Hypocalcemia (<8.4 mg/dL) was present in 5% of patients, whereas 17.8% of patients presented hypercalcemia (>10.2 mg/dL), 60.3% of whom received vitamin D. Hypophosphoremia (<3.5 mg/dL) was present in 16% of patients, and 29% of patients presented hyperphosphoremia (>5.5 mg/dL). Ca x P was <55 mg2/dL2 in 73% of patients. Thirty one percent of patients presented secondary hyperparathyroidism (HPTH >300 pg/mL), being severe in 12% (>600 pg/mL); 43% of patients presented iPTH <150 pg/mL. Only 7.3% of patients achieved the four recommendations provided in the K/DOQI guidelines. Vitamin D treatment was administered in 48% of patients.

CONCLUSIONS

The population undergoing dialysis in the community of Valencia achieved targets based on the clinical recommendations of the K/DOQI guidelines as follows: 45% of patients achieved targets for calcium, 55% for phosphorus, 73% for Ca x P and 26% for iPTH levels. Surprisingly, only 7.3% of patients achieved all four targets.