Serum iPTH Concentrations Research Articles

Longitudinal study on the change trend of serum alkaline phosphatase and its possible influencing factors in peritoneal dialysis patients

The aim of the study was to analyze the change trend of serum ALP over time and identify factors influencing its levels in peritoneal dialysis patients. Then to investigate the impact of serum ALP changes on calcium and phosphorus metabolism in single peritoneal dialysis center utilizing repeated measurement data. A retrospective cohort study was conducted with a total follow-up duration of 30 months. Serum ALP and other biomarkers, including calcium (Ca), phosphorus (P), 25(OH)D, intact parathyroid hormone (iPTH), albumin(ALB), and hemoglobin(Hb) were measured every 3 months. The generalized estimation equation (GEE) was utilized to analyze the change trend of serum ALP over time, and to assess whether there were differences in changes over time between different genders and different primary disease groups. Additionally, factors influencing serum ALP levels were analyzed, and the impact of serum ALP changes on calcium and phosphorus metabolism was also explored. A total of 34 patients were included in the study. Serum ALP and other indicators were measured repeatedly, with a maximum of 8 times and a minimum of 4 times. The median of serum ALP values at all measurement times for all selected patients was 89 U/L. The GEE analysis revealed that serum ALP gradually increased with time, and patients in diabetes group increased faster than those in non-diabetes group. A positive correlation was observed between serum ALP and dialysis duration, also between serum ALP and hemoglobin. However, variations in serum ALP did not significantly affect serum corrected calcium, phosphorus, or iPTH concentrations. The serum ALP levels of peritoneal dialysis patients increase gradually over time, and the concentrations are influenced by dialysis duration. The changes in serum ALP values do not have a significant impact on serum calcium, phosphorus, and iPTH levels.

Association between baseline intact parathyroid hormone levels, COVID-19 severity, and long-term outcomes in patients undergoing hemodialysis: A multicenter retrospective study

The COVID-19 pandemic poses unique challenges for vulnerable populations, including patients undergoing maintenance hemodialysis (HD). This study explores the relationship between baseline intact parathyroid hormone (iPTH) levels and COVID-19 severity, post-acute hospitalization, and mortality rates in HD patients.
 Methods. A multicenter retrospective cohort study was conducted across multiple centers, encompassing 142 patients undergoing HD treatment in three regions of Ukraine. The study spanned from March 2020 to May 2022. Baseline iPTH levels, demographic characteristics, and relevant clinical indicators were systematically recorded. Key endpoints included the severity of COVID-19, post-acute hospitalization, and mortality rates.
 Results. Of the initially eligible 165 patients, 23 were excluded, resulting in a final cohort of 142 patients. During the acute phase of COVID-19, distinct patterns emerged in terms of hospitalization rates, oxygen support requirements, and mortality. Lower iPTH levels were significantly associated with severe COVID-19-associated pneumonia (p < 0.0001). A 20-month follow-up revealed a significant association between serum iPTH concentration <174 pg/mL and increased rates of post-acute COVID-19 hospitalization [HR 6.3 (95% CI 2.9; 13.7)] and all-cause mortality [HR 34.3 (95% CI 6.9; 74.5)].
 Conclusion. This multicenter retrospective study suggests potential links between baseline iPTH levels and COVID-19 outcomes in patients undergoing HD. Serum iPTH concentration ≤174 pg/mL was significantly associated with increased post-acute hospitalization and mortality rate in our patient cohort. The findings emphasize the need for further research to elucidate underlying mechanisms and establish the prognostic value of iPTH in this specific patient population.

Radiofrequency ablation for patients with recurrent or persistent secondary hyperparathyroidism after parathyroidectomy: initial experience.

Reoperation for recurrent or persistent secondary hyperparathyroidism (SHPT) after parathyroidectomy is challenging due to surgical scars and postoperative adhesions. Therefore, there is an increasing need to develop a new minimally invasive therapy. To analyze the efficacy of ultrasound (US)-guided radiofrequency ablation (RFA) in patients with recurrent or persistent SHPT after parathyroidectomy. From March 2013 to January 2022, 20 enlarged parathyroid glands in 10 patients with recurrent or persistent SHPT were treated with US-guided RFA. The levels of serum intact parathyroid hormone (iPTH), calcium (Ca), phosphorus (P), and alkaline phosphatase (ALP), as well as clinical symptoms, were compared before and after RFA. The ablation procedure-related complications were also evaluated. The target range for iPTH levels was approximately 2-9 times the upper limit of normal (130-585 pg/mL). The mean follow-up time was 49.6 ± 34.5 months (range from 6 to101 months). The levels of serum iPTH, Ca, and P decreased significantly one day post-ablation. Six months after RFA, 70% of patients reached the targets for iPTH, and 50% of patients reached targets at the end of follow-up. Two patients underwent repeat ablation at 9 months and 6 years after RFA, respectively, due to persistently elevated iPTH levels, and both had serum iPTH concentrations in the recommended range at the recent follow-up visit. The patients' clinical symptoms significantly improved after ablation. Major complications after RFA included hoarseness (2/10) and permanent hypoparathyroidism (1/10). Severe hypocalcemia occurred in four patients (4/10) after ablation. US-guided percutaneous RFA for recurrent or persistent SHPT is safe, efficacious, and repeatable, and can significantly improve hyperparathyroidism-related symptoms.

Predictors of early postoperative hypocalcemia in patients with secondary hyperparathyroidism undergoing total parathyroidectomy.

ObjectiveTo summarize the clinical features of secondary hyperparathyroidism (SHPT) in patients with chronic renal failure and to explore the predictive factors of postoperative hypocalcemia after total parathyroidectomy in these patients.MethodsThe clinical data of 87 patients admitted to Guangdong Electric Power Hospital from May 2013 to February 2020 were reviewed. All patients underwent total parathyroid resection and sternocleidomastoid microtransplantation. Age, sex, and the serum calcium, phosphorus, alkaline phosphatase (ALP), and intact parathyroid hormone (iPTH) concentrations were analyzed as predictive factors of postoperative hypocalcemia.ResultsBone pain was the most common clinical manifestation in this study population, and all 87 patients experienced relief from their clinical symptoms after the surgical procedure. Age and the preoperative serum calcium, ALP, and iPTH concentrations were determined to be early predictive factors of postoperative hypocalcemia.ConclusionsAge and the preoperative calcium, ALP, and iPTH concentrations are independent risk factors for postoperative hypocalcemia in patients with SHPT and renal disease who undergo total parathyroidectomy with sternocleidomastoid microtransplantation. These factors can help identify high-risk patients who can be managed by a multidisciplinary team to improve graft survival and quality of life.

Seasonal variation of serum 25-hydroxyvitamin D and parameters of bone and mineral disorder in dialysis patients.

Vitamin D deficiency is common among dialysis patients and may impact blood concentrations of calcium, phosphorus, intact parathyroid hormone (iPTH), and alkaline phosphatase (ALP). Seasonal variation of serum 25-hydroxyvitamin D [25(OH)D] concentrations has been well established for the general population; however, less is known about circannual variation in 25(OH)D as well as other parameters of mineral and bone disorder among dialysis patients. Based on 57,500 serum 25(OH)D measurements collected over two years from January 2009 to December 2010 among 25,025 dialysis patients, we evaluated the circannual variations in serum concentrations of 25(OH)D, calcium, phosphorus, iPTH, and ALP by a linear regression model with a cosinor function for the time period (month). We adjusted for potential confounders including case-mix variables, and ultraviolet index. Serum 25(OH)D concentrations showed significant circannual variation and mean serum 25(OH)D was 3.2 ng/mL higher in summer than in winter. Furthermore, 25(OH)D concentration increased steadily by 1.3 ng/mL per year. While serum calcium concentrations showed statistically significant but clinically negligible seasonal variation (0.02 mg/dL in peak-trough difference), serum phosphorus did not follow such a pattern. Serum iPTH concentrations also showed a modest seasonal variation with 9% higher values in winter than in summer. Concordantly, ALP concentrations in the winter were 2% higher than in the summer time. Seasonal variation of 25(OH)D was greater in male (vs. female), African-American (vs. non-African-American), and younger (vs. older) dialysis patients. Serum 25(OH)D and iPTH concentrations show seasonal variation among dialysis patients while the variation in other parameters of mineral and bone disorder was clinically irrelevant, if any. Serum 25(OH)D also showed a gradual increase over time. Clinicians and researchers should be aware of these changes when interpreting laboratory results in dialysis patients.

Hypocalcemia-based prediction of hungry bone syndrome after parathyroidectomy in hemodialysis patients with refractory secondary hyperparathyroidism.

ObjectiveThis study was performed to explore the risk factors for hungry bone syndrome (HBS) and establish prediction equations for calcium supplementation after parathyroidectomy in hemodialysis patients with secondary hyperparathyroidism.MethodsWe retrospectively analyzed data from 252 hemodialysis patients undergoing successful total parathyroidectomy with autotransplantation. HBS was defined according to a minimum postoperative serum corrected calcium (PcCa) concentration of <2.0 mmol/L. Independent predictors of HBS were analyzed, and prediction equations for HBS were derived accordingly.Results The incidence of HBS was 71.4%. The serum corrected calcium and preoperative serum alkaline phosphatase (ALP) concentrations were independent predictors of HBS. The preoperative serum ALP, intact parathyroid hormone (iPTH), and hemoglobin concentrations were independent factors influencing the average descending velocity of the PcCa concentration before calcium supplementation (PcCa-V), intravenous calcium supplement holding time (IVCa-T), and intravenous calcium supplement dosage (IVCa), while the serum ALP and iPTH concentrations were independent predictors of the oral calcium supplement dosage (OCa). Four prediction equations for PcCa-V, IVCa-T, IVCa, and OCa were established.ConclusionsEstablishment of prediction equations for HBS may contribute to a new individualized therapy for patients with HBS.

Impact of Altered Mineral Metabolism on Pathological Cardiac Remodeling in Elevated Fibroblast Growth Factor 23.

Clinical and experimental studies indicate a possible link between high serum levels of fibroblast growth factor 23 (FGF23), phosphate, and parathyroid hormone (PTH), deficiency of active vitamin D (1,25D) and klotho with the development of pathological cardiac remodeling, i.e., left ventricular hypertrophy and myocardial fibrosis, but a causal link has not been established so far. Here, we investigated the cardiac phenotype in klotho hypomorphic (kl/kl) mice and Hyp mice, two mouse models of elevated FGF23 levels and klotho deficiency, but differing in parameters of mineral metabolism, by using histology, quantitative real-time PCR, immunoblot analysis, and serum and urine biochemistry. Additionally, the specific impact of calcium, phosphate, PTH, and 1,25D on hypertrophic growth of isolated neonatal rat cardiac myocytes was investigated in vitro. Kl/kl mice displayed high serum Fgf23 levels, increased relative heart weight, enhanced cross-sectional area of individual cardiac myocytes, activated cardiac Fgf23/Fgf receptor (Fgfr) 4/calcineurin/nuclear factor of activated T cell (NFAT) signaling, and induction of pro-hypertrophic NFAT target genes including Rcan1, bMHC, brain natriuretic peptide (BNP), and atrial natriuretic peptide (ANP) as compared to corresponding wild-type (WT) mice. Investigation of fibrosis-related molecules characteristic for pathological cardiac remodeling processes demonstrated ERK1/2 activation and enhanced expression of Tgf-β1, collagen I, and Mmp2 in kl/kl mice than in WT mice. In contrast, despite significantly elevation of serum and cardiac Fgf23, and reduced renal klotho expression, Hyp mice showed no signs of pathological cardiac remodeling. Kl/kl mice showed enhanced serum calcium and phosphate levels, while Hyp mice showed unchanged serum calcium levels, lower serum phosphate, and elevated serum iPTH concentrations compared to corresponding WT mice. In cultured cardiac myocytes, treatment with both calcium or phosphate significantly upregulated endogenous Fgf23 mRNA expression and stimulated hypertrophic cell growth and expression of pro-hypertrophic genes. The treatment with PTH induced hypertrophic cell growth only, and stimulation with 1,25D had no significant effects. In conclusion, our data indicate that Hyp mice, in contrast to kl/kl mice appear to be protected from pathological cardiac remodeling during conditions of high FGF23 levels and klotho deficiency, which may be due, at least in part, to differences in mineral metabolism alterations, i.e., hypophosphatemia and lack of hypercalcemia.

MIBI scintigraphy of parathyroid adenomas: correlation with biochemical and histological markers

ABSTRACTPurpose: In this study, we tested the hypothesis that MIBI-positive and MIBI-negative adenomas of parathyroid glands (APGs) have distinct biochemical and histological markers that could help differentiate MIBI-positive from MIBI-negative APGs. Patients and methods: 40 patients with 41 APGs were included in the study. Patients were enrolled in the study after MIBI scintigraphy examinations had been carried out. Biochemical analyses included serum levels of calcium (Ca), intact parathyroid hormone (iPTH), and 25-hydroxyvitamin D3 (25-OH-D3). All patients had neck ultrasound and MIBI examinations. After surgical resection the APGs were examined histologically. Results: In each of 39 patients one APG could be confirmed by histology, and in one patient, two contralateral APGs were identified. MIBI studies were positive in 73 % and negative in 27 % of the APGs. False-positive cases were not observed. MIBI-negative APGs were only present in patients with iPTH values below 150 pg/ml. In 82 % of MIBI negative studies oxyphilic cells were absent, and this cell type was present in only 18 % of MIBI negative cases (p < 0.001). Regarding cysts within the APGs, no differences were demonstrated between MIBI positive or negative studies (p = 0.32). Fat cells were seen in none of the MIBI -negative studies and in only 3 % of MIBI positive studies (p = 0.08). Conclusions: For APGs, MIBI positivity correlates with serum iPTH concentration. The absence of oxyphilic cells with large numbers of mitochondria in APGs contributes to MIBI negativity, probably because of the reduced binding sites for the radiotracer.

A Vitamin D-Calcium-Fortified Yogurt Drink Decreased Serum PTH but did not Affect Osteocalcin in Subjects with Type 2 Diabetes.

There is sparse evidence of the effect of vitamin D on bone biomarkers in diabetic patients, and therefore, in a randomized clinical trial, we evaluated the effects of the daily intake of vitamin D, either with or without extra calcium, on selected bone biomarkers. Ninety women and men aged 30 - 50 years old with type 2 diabetes were randomly divided into three groups in a double-blind manner. Group 1 (PD), the control group, received a plain yogurt drink. Groups 2 (DD) and 3 (CDD) received 1000 IU vitamin D3, and 1000 IU vitamin D3 plus 500 mg calcium, respectively, via drinking two 250 mL bottles a day of a fortified yogurt drink for twelve weeks. Anthropometric and biochemical assessments were made, including 25(OH), intact parathyroid hormone (iPTH), osteocalcin, and calcium. Although the time and time × group interaction effects on the bone biomarkers were not statistically significant, there was a modest decrease in iPTH concentrations in both DD and CDD groups over twelve weeks. The subgroups with initial vitamin D deficiency/insufficiency in the CDD group had greater and significant decrease in serum iPTH concentrations after twelve weeks of treatment compared to the PD group (- 9.0 ± 21.2 v.s 8.6 ± 21.8 pg/mL, p = 0.042). The improvement in vitamin D status following the daily intake of fortified doogh for twelve weeks was accompanied by a decrement in iPTH, mostly in those subjects with poor initial vitamin D status.

Effect of low-calcium dialysate on low-turnover renal osteodystrophy in elderly patients with maintenance hemodialysis

Objective To study the effects of low-calcium dialysate on the calcium-phosphorus metabolism, parathyroid function and vascular calcifications in elderly patients with low turnover renal osteodystrophy undergoing maintenance hemodialysis (MHD). Methods 80 MHD elderly patients (aged≥60 years) who were in stable condition over 6 months and with two consecutive serum intact parathyroid hormone (iPTH) <100 ng/L were observed for 12 months and randomly classified into the control group (calcium 1.50 mmol/L of dialysate, n=40) and the treatment group (calcium 1.25 mmol/L of dialysate, n=40). The changes of serum iPTH, calcium, phosphorus, calcium and phosphorus product and other indicators as well as related adverse reactions were observed and recorded before and 1, 3, 6 and 12 months after treatment. In addition, the intima-media thickness (IMT) of carotid artery and abdominal aorta calcification score (AACS) were measured in the patients before and 6 and 12 months after treatment. Results In the treatment group, serum corrected calcium, phosphorus, and calcium-phosphate product began to decline after 1 month and a further decline at 3 months later, and serum iPTH level was significantly increased after 1 month and gradually increased at 3 months later. The above markers were stabilized after 6 months of treatment, and there were significant differences in the changes of the above markers before and after treatment (all P 0.05). Conclusions The low calcium dialysate (1.25 mmol/L) can prominently control the levels of serum calcium, phosphorus and calcium-phosphorus product, effectively improve the over-suppressed parathyroid function and vascular calcifications, and has a good security in elderly MHD patients with serum iPTH concentration <100 ng/L. Key words: Kidney failure, chronic; Hemodia filtration; Parathyroid hormone; Hemodialysis solutions

Fibroblast growth factor 23 (FGF23) and early chronic kidney disease in the elderly

Better biomarkers of CKD reflecting responses to decreased glomerular filtration rate (GFR) are needed. We determined the value of estimated GFR (eGFR) as a threshold for the increase of plasma cFGF23 (C-terminal) and intact fibroblast growth factor-23 (iFGF23) (intact) concentrations in the course of chronic kidney disease (CKD) and compared this eGFR value with values related to increased serum intact parathyroid hormone (iPTH) or phosphorus concentrations in an elderly population. We measured plasma iFGF23, cFGF23, serum phosphorus, calcium, albumin, creatinine, urea, cystatin C, iPTH and vitamin 25-OH-D3 in 3780 population-based study participants aged ≥ 65 years. Serum phosphorus concentrations hardly increased until mean eGFR reached 47.3 ± 4.7 mL/min/1.73 m(2) but then increased exponentially. Similarly, both iPTH and iFGF23 increased slightly in early CKD but then increased exponentially when eGFR reached 55.0 ± 4.2 mL/min/1.73 m(2) for iPTH and 51.6 ± 5.7 mL/min/1.73 m(2) for iFGF23. The departure point for exponential increases in cFGF23 preceded those for iPTH and iFGF23 and occurred at a mean eGFR of 57.7 ± 7.8 mL/min/1.73 m(2). The prevalence of increased iFGF23 occurred at a remarkably higher eGFR value than that of cFGF23 across the CKD stages. The increase in cFGF23 preceded both the increase in iPTH and iFGF23 as eGFR declined. Increased plasma iFGF23 level did not precede the rise in serum iPTH concentrations and did not occur before stage-3 CKD in elderly persons. However, cFGF23 was not an early marker of CKD in the elderly subjects.

Spectral Doppler Analysis of Parathyroid Adenoma: Correlation Between Resistive Index and Serum Parathyroid Hormone Concentration

The purpose of this study was to evaluate the correlation between spectral wave analyses by measuring the resistive index and serum intact parathyroid hormone (iPTH) concentration in primary hyperparathyroidism. From March 2008 to April 2012, 46 consecutively registered patients underwent color and spectral Doppler ultrasonography for determination of vascularity and vascular resistance of parathyroid adenoma. The color Doppler sonographic findings were compared with methoxyisobutylisonitrile (MIBI) scintigraphic findings, serum iPTH concentration, and the volume of the gland. The mean resistive index in parathyroid adenoma was 0.69 ± 0.12. The study showed a strong negative relation between resistive index and serum iPTH concentration. There was a significant negative relation between the volume of the gland and the resistive index. There is a relation between degree of perfusion in parathyroid adenoma and serum iPTH concentration. Resistive index may be an objective alternative parameter for determining the vascularity of adenoma for monitoring of response to alcohol ablation therapy and medical management.

Effectiveness of an i-PTH Measurement in Predicting Post Thyroidectomy Hypocalcemia: Prospective Controlled Study

PurposeHypocalcemia is the most common complication after total thyroidectomy. The purpose of this study was to determine whether measurement of intact parathyroid hormone (i-PTH) level in thyroidectomy patients could predict hypocalcemia.Materials and MethodsWe performed a prospective study of patients undergoing total thyroidectomy. Serum concentration of i-PTH, total calcium (Ca), ionized calcium (Ca2+), phosphate (P), magnesium (Mg), and albumin were measured preoperatively and at 0 hour, 6 hours, 12 hours, 24 hours, 48 hours, and 72 hours postoperatively.Results108 patients were recruited to the study. A total of 50 patients (46%) experienced hypocalcemia. The serum i-PTH concentration was linearly related to the time of measurement, while concentrations of P, Mg, albumin, Ca, and Ca2+ were not. We compared odds ratios, and found that the concentration of i-PTH at 6 hours post operation was the most closely related to the occurrence of hypocalcemic symptom. On ROC analysis using i-PTH level at 6 hours, an i-PTH level of 10.6 mg/dL was found to maximize both sensitivity and specificity at the same time point.ConclusionWe found that i-PTH was a predictor of hypocalcemia, and that the earliest predictor of hypocalcemic symptoms was an i-PTH concentration lower than 10.6 mg/dL obtained 6 hours after total thyroidectomy.

Optimal Serum Concentration of 25-Hydroxyvitamin D for Bone Health in Older Korean Adults

Optimal vitamin D concentrations for bone health have not been determined in the Korean population. The aim of this study was to define serum 25-hydroxyvitamin D (25[OH]D) concentrations that indicate insufficiency among older Korean adults as measured by serum intact parathyroid hormone (iPTH) concentrations and bone mineral density (BMD). We analyzed data from the Fourth Korea National Health and Nutrition Examination Survey (KNHANES IV-3), which was conducted in Korea in 2009. We enrolled 1,451 men and 1,870 women aged 49 years and above. After adjusting for variables that could potentially affect serum 25(OH)D concentrations, we found that serum iPTH concentrations began to increase at serum 25(OH)D concentrations below 12.1 ng/mL (30.2 nmol/L). In addition, total-femur BMD increased until serum 25(OH)D concentrations dropped below 20.4 ng/mL (50.9 nmol/L); no significant changes were observed thereafter. Assuming that serum 25(OH)D concentrations below 12.1 and 20.4 ng/mL represent vitamin D insufficiency, the prevalences of vitamin D insufficiency were 8.7 and 50.4 % in men and 17.9 and 66.3 % in women, respectively. Serum 25(OH)D cutoff values of 12.1 ng/mL (OR = 1.26) and 20.4 ng/mL (OR = 1.54) were associated with osteoporosis (P < 0.01); osteoporosis was not associated with a 25(OH)D cutoff value of 30 ng/mL (75.0 nmol/L). In conclusion, serum 25(OH)D concentrations of 20 ng/mL might be sufficient for bone health in older Korean adults.

Cinacalcet Treatment for Stable Kidney Transplantation Patients With Hypercalcemia due to Persistent Secondary Hyperparathyroidism: A Long-term Follow-up

BackgroundCinacalcet is an effective treatment for hypercalcemia due to persistent hyperparathyroidism (HPT) in patients who have undergone kidney transplantation (KT). Few data are available about their long-term follow-up. ObjectiveWe aimed to evaluate the long-term efficacy of cinacalcet in functioning stable KT subjects with hypercalcemia secondary to persistent HPT. Material and MethodsTwenty-three patients (6 men) with a stable KT showed persistent hypercalcemia (>12 months) secondary to HPT (parathyroid hormone by radioimmunoassay [iPTH] > 150 pg/mL). The mean age was 54 ± 13 years. Time after KT to beginning cinacalcet treatment was 36.5 ± 37.9 (range 12 to 172) months. Initial cinacalcet doses were 30 mg/d. Median follow-up was 53 ± 7.4 months (range 42 to 60 months). We determined serum calcium, phosphorus, alkaline phosphatase, iPTH, creatinine, and immunosuppressant concentrations at baseline as well as 3, 6, and 12 months and after every 6 months thereafter. ResultsInitial serum calcium was 11 ± 0.65 mg/dL and mean calcium during treatment, 10.25 ± 0.81 mg/dL (P < .001). Initial serum phosphorus was 2.8 ± 0.58 mg/dL and mean value serum phosphorus during the treatment period, 3.13 ± 0.6 mg/dL (P = 0.015). Initial iPTH was 260 ± 132 pg/mL and during the treatment period; 237 ± 131 pg/mL (P = ns). There was no change in renal function nor in immunosuppressant blood levels. Doses of cinacalcet at the end of the follow-up were 40.4 ± 18.9 mg/d. ConclusionCinacalcet was effective for long-term control of hypercalcemia related to persistent HPT for patients with stable KT.

A 12-week double-blind randomized clinical trial of vitamin D3supplementation on body fat mass in healthy overweight and obese women

BackgroundVitamin D concentrations are linked to body composition indices, particularly body fat mass. Relationships between hypovitaminosis D and obesity, described by both BMI and waist circumference, have been mentioned. We have investigated the effect of a 12-week vitamin D3 supplementation on anthropometric indices in healthy overweight and obese women.MethodsIn a double-blind, randomized, placebo-controlled, parallel-group trial, seventy-seven participants (age 38±8.1 years, BMI 29.8±4.1 kg/m2) were randomly allocated into two groups: vitamin D (25 μg per day as cholecalciferol) and placebo (25 μg per day as lactose) for 12 weeks. Body weight, height, waist, hip, fat mass, 25(OH) D, iPTH, and dietary intakes were measured before and after the intervention.ResultsSerum 25(OH)D significantly increased in the vitamin D group compared to the placebo group (38.2±32.7 nmol/L vs. 4.6±14.8 nmol/L; P<0.001) and serum iPTH concentrations were decreased by vitamin D3 supplementation (-0.26±0.57 pmol/L vs. 0.27±0.56 pmol/L; P<0.001). Supplementation with vitamin D3 caused a statistically significant decrease in body fat mass in the vitamin D group compared to the placebo group (-2.7±2.1 kg vs. -0.47±2.1 kg; P<0.001). However, body weight and waist circumference did not change significantly in both groups. A significant reverse correlation between changes in serum 25(OH) D concentrations and body fat mass was observed (r = -0.319, P = 0.005).ConclusionAmong healthy overweight and obese women, increasing 25(OH) D concentrations by vitamin D3 supplementation led to body fat mass reduction.This trial is registered at clinicaltrials.gov as NCT01344161.

Parathyroidectomy for the attainment of NKF-K/DOQI™ and KDIGO recommended values for bone and mineral metabolism in dialysis patients with uncontrollable secondary hyperparathyroidism

The National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF-K/DOQI™) 2003 and Kidney Disease: Improving Global Outcomes (KDIGO) 2009 have established guidelines for the treatement of secondary hyperparathyroidism. This study evaluated the impact of parathyroidectomy to achieve recommended values for parathyroid hormone, calcium, phosphorus and CaxPO(4) product in dialysis patients with severe secondary hyperparathyroidism that is resistant to medical treatment. This study included 43 consecutive patients who underwent parathyroidectomy for a severe form of secondary hyperparathyroidism (SHPT) that is unresponsive to medical treatment. The serum iPTH, calcium and phosphorus levels were measured prior to surgery, every morning after surgery for 5days and on the first, sixth and eighth postoperative months. Following parathyroidectomy, a significant decline in iPTH values was observed in all patients; however, after the 8-month study period, only one of these patients achieved a serum iPTH concentration within the K/DOQI recommended target range. Unlike iPTH, targeting for calcium, phosphorus and CaxPO(4) at the last follow-up were 55.8%, 60.5% and 93%, respectively. These values indicated a significant improvement in comparison to preoperative percentages. In regards to the KDIGO recommended guidelines, the iPTH levels did not significantly change at the end of our study compared to preoperative values; however, calcium levels significantly declined and phosphorus levels significantly improved compared to preoperative values. Although the majority of patients fail to reach recommended iPTH values, parathyroidectomy remains a valuable tool to attain these NKF-K/DOQI recommendations for serum calcium, phosphorus and CaxPO(4) in dialysis patients with secondary hyperparathyroidism resistant to medical therapy. Parathyroidectomy was shown to be an inadequate intervention for achieving KDIGO recommendations.

Treatment of Hyperparathyroidism With Cinacalcet in Kidney Transplant Recipients

Background After successful kidney transplantation, hyperparathyroidism can persist in 10%–50% of patients and can harmfully affect bone metabolism. Calcimimetic cinacalcet is a new treatment option in the management of persistent hyperparathyroidism in these patients. Methods This prospective, clinical study of 11 patients included those who had a serum intact parathyroid hormone (iPTH) concentration >65 ng/L, a serum creatinine concentration was <200 μmol/L, stable kidney graft function, and were >1 year since transplantation. Patients were not treated with drugs other than calcitriol that could influence bone metabolism. During the 6-month observation period, in which the stability of measured parameters was determined, and in the 12-month treatment period (cinacalcet 30 mg/d), we followed serum concentrations of calcium, phosphate, iPTH, creatinine, vitamin 25OH D 3, bone-specific alkaline phosphatase (ALP), osteocalcin, collagen degradation fragments (CTX), urinary calcium excretion, and bone mineral density (BMD). Results During the treatment period, the serum calcium concentration decreased significantly (from 2.50 ± 0.12 to 2.32 ± 0.12 mmol/L; P < .01). Serum iPTH concentration decreased significantly (from 247 [range, 199–362] at time 0 to 198 [range, 165–233] ng/L after 1 month of treatment; P < .05), but increased slightly thereafter. After 6 months of treatment, the serum concentration of ALP and CTX increased significantly, but decreased thereafter. There were no significant changes in the other parameters assessed. Renal function remained stable during the treatment period. The BMD of the lumbar spine, hip, and forearm did not change during the 12 months of treatment. Conclusion Cinacalcet was effective in treating posttransplant hyperparathyroidism, resulting in decreased calcemia and transient decreased iPTH. ALP and CTX transiently increased during therapy, but other markers of bone metabolism remained unchanged. Twelve months of cinacalcet treatment did not result in a change in BMD. Cinacalcet seems to be a safe drug with no negative effect on renal function.

A haemodialysis patient with back pain: brown tumour as a cause of spinal cord compression under cinacalcet therapy.

A 43-year-old haemodialysis patient was admitted to hospital because of paroxysmal pain in the upper abdominal region radiating to the back. Laboratory tests showed severe hyperparathyroidism [intact parathyroid hormone (iPTH) 69 pmol/L; reference range: 1.3–6.8 pmol/L], hypercalcaemia (2.79 mmol/L), hyperphosphataemia (1.6 mmol/L) and elevated serum total alkaline phosphatase (200 U/L). After developing a disturbed sensation and paraesthesia in both feet, epidural compression of the spinal cord was suspected. Magnetic resonance imaging showed a tumour that severely compressed the myelum of the thoracic spine. Histological investigation revealed a brown tumour or osteoclastoma, an erosive bony lesion caused by increased osteoclastic activity and peritrabecular fibrosis. A brown tumour is a benign tumour that is a rare complication of severe renal hyperparathyroidism. The brown tumour developed despite a 1-year treatment of the patient with cinacalcet, which, however, did not result in a major decrease in serum iPTH concentration (from 110 to 69 pmol/L: 37% reduction). Urgent decompressive neurosurgery and subtotal parathyroidectomy resulted in a complete recovery.

The Effects of Regular Tanning Bed Use and Increased Vitamin D Status on Serum Markers of Bone Turnover in Healthy Adult Women

Background Vitamin D is a key nutrient in bone health and the vitamin D status of individuals with regular exposure to solar or artificial ultraviolet B (UVB) radiation is generally superior to those with limited exposure. Objective By means of a cross-sectional, observational design, explore the association of serum 25-hydroxy vitamin D (25(OH)D) concentrations and biochemical markers of bone turnover across a spectrum of vitamin D status by comparing women who regularly use tanning beds with women of minimal UVB exposure. Methods A total of 69 healthy women, ages 25–82 y, were recruited. Serum concentrations of 25(OH)D, intact parathyroid hormone (iPTH), leptin, bone-specific alkaline phosphatase (BAP), osteocalcin (OC), and C-terminal telopeptides of Type I collagen (CTx) were measured. Results There were no significant differences in age, height, weight, BMI and dietary intakes between groups. Serum 25(OH)D concentrations were significantly higher in tanners (n = 20) compared with non-tanners (n = 49) (p &lt; 0.0001). Serum iPTH concentrations were lower in tanners than in non-tanners (p &lt; 0.0001) and were negatively correlated with serum 25(OH)D concentrations (r = –4571, p &lt; 0.0001). Of the bone turnover markers, only serum OC concentrations were lower in tanners compared with non-tanners (p = 0.0002). After adjusting for age and menopausal status, osteocalcin was negatively correlated (r = –0.0178; p = 0.04) with 25(OH)D and positively correlated with iPTH (r = 0.035; p = 0.05). Conclusions Our results show healthy women with regular UVB exposure via tanning beds have significantly greater vitamin D status and lower serum osteocalcin concentrations than those without and that there is a significant inverse relationship between serum serum 25(OH)D and osteocalcin concentrations which appears to be PTH-dependent.