Intact Parathyroid Hormone Values Research Articles

Predicting tumor volume in primary hyperparathyroidism from preoperative clinical data.

Primary hyperparathyroidism (PHPT) is an endocrine disorder that is treated surgically, and some correlation between the size of the responsible lesion and preoperative clinical data is assumed. The purpose of this study was to predict tumor volume of the lesion responsible for PHPT from preoperative clinical data. Participants comprised patients with surgically treated PHPT who underwent initial surgery in our department between January 2000 and December 2021. The volume of parathyroid gland removed was used as the primary outcome and associations with preoperative clinical data were assessed by multivariable analysis. A positive correlation was identified between parathyroid tumor volume and both preoperative intact parathyroid hormone (PTH) (Spearman's r = 0.503) and calcium values (Spearman's r = 0.338). Data for intact PTH value and tumor volume were logarithmically transformed (ln-PTH = log-transformed intact PTH value; ln-volume = log-transformed tumor volume). Multiple regression analysis revealed male sex, ln-PTH and calcium values as significant predictors of ln-volume, with standardized regression coefficients of 0.213 (95% confidence interval [CI] 0.103-0.323), 0.5018 (95%CI 0.4442-0559) and 0.322 (95%CI 0.0339-0.149), respectively. The adjusted R2 for this model is 0.320. Preoperative serum intact PTH value is associated with tumor volume of the lesion responsible for PHPT. A rough estimation of the tumor size would provide responsible physicians with opportunities to add further imaging tests or plan appropriate surgical strategies.

Different types of hip fragility fractures have different values of 25-hydroxyvitamin D and parathyroid hormone

BackgroundVitamin D insufficiency/deficiency is related to fragility fracture. In most previous studies, there was no assessment of vitamin D deficiency status separately for hip fracture types. The first aim is to evaluate vitamin D and parathyroid hormone (PTH) status in patients with hip fracture. The second objective is to determine whether there are differences in vitamin D and PTH between the femoral neck fracture and the femoral metaphyseal fracture group. Methods62 men and 248 women with fragility hip fractures were enrolled. 25-hydroxyviamin D [25(OH)D] and intact PTH (iPTH) values were evaluated, and femoral neck bone mineral density (BMD) was measured on the uninjured side. Vertebral fractures (VFs) were assessed using radiographs of the thoracic and lumbar spine. We examined the relationships of 25(OH)D value with the number of prevalent VFs, T-score of femoral neck, and iPTH level. These analyses were also performed, neck fracture and trochanteric fracture separately. ResultsMean age was 85 years. The mean 25(OH)D was 11.2 (range, 4.0–26.1) ng/ml, whereas the mean iPTH value was 48.9 pg/ml (range, 9–429 pg/ml). The mean number of VFs was 1.5 (range, 0–11), and the mean T-score was −3.3 (range, −5.2 to −0.5). There was a weak correlation between the 25(OH)D value and the number of VFs. There was a weak but significant correlation between 25(OH)D and iPTH values. In the patients with trochanteric fractures, 25(OH)D value was significantly lower and iPTH value was significantly higher than those with neck fractures. There was a significant correlation between the 25(OH)D value and number of the VFs, 25(OH)D, and iPTH values only in trochanteric fractures. ConclusionsVitamin D deficiency was severe and PTH levels were higher in the trochanteric fractures. Both vitamin D deficiency and high PTH levels were suggested to have association with bone fragility.

Analysis of intraoperative laboratory measurements and imaging techniques such as Tc-99m-MIBI SPECT/CT, 18F-fluorocholine PET/CT and ultrasound in patients operated with prediagnosis of parathyroid adenoma.

The aim of this study is to determine accurately the localization of the adenoma with the imaging methods in the patients, who are planned to be operated on with prediagnosis of parathyroid adenoma. In our study, the files of the patients who were considered to have parathyroid adenoma and underwent operation between 2012 and 2020 with the methods such as Tc99m-MIBI SPECT/CT, 18F-fluorocholine PET/CT, and ultrasound, and biochemical examinations were examined retrospectively. In this study, 31 (18.2%) male and 139 (81.8%) female adult patients were included. The sensitivities of localization methods were 82.6% for ultrasound and 78.4% for scintigraphy. Adenoma was localised in the right place in 14 of 15 (93.3%) patients with the 18F-fluorocholine PET/CT method. A statistically significant correlation was found between the sensitivity of scintigraphy, the gland weights (p: 0.002), and phosphor values (p: 0.039). A statistically significant improvement was observed in the intact PTH value (p: 0.001) 15min after the removal of adenoma. A statistically significant improvement was observed in the serum PTH value (p: 0.001), the serum phosphorus value (p: 0.001), and the serum calcium (p: 0.001) in the first 3months after the operation. Determining localization accurately for the patients enables performing operations with minimally invasive surgery successfully in a shorter time. Also, fewer complications and faster recovery are seen in the patients. It was concluded that studying intraoperative intact PTH and using 18F-fluorocholine PET/CT method for localization give more accurate results for localization and allow having more successful operation outcomes.

Intact parathyroid hormone value on the first postoperative day following total thyroidectomy as a predictor of permanent hypoparathyroidism: a retrospective analysis on 426 consecutive patients.

Hypoparathyroidism represents a common complication following total thyroidectomy. To date, there is still no reliable and immediate postoperative parameter to establish which patients with postsurgical hypoparathyroidism will develop permanent hypoparathyroidism. The main purpose of the present study was to assess whether the intact parathyroid hormone (iPTH) value on the first postoperative day is a good predictor of permanent hypoparathyroidism. Patients undergoing thyroidectomy in our unit between March 2018 and January 2020 were analysed. According to the iPTH value on the first postoperative day and on the basis of the detection threshold of the iPTH test used, patients were divided into two groups: Group A (iPTH ≥ 4.6 pg/mL) and Group B (iPTH < 4.6 pg/mL, undetectable). In total 426 patients were included: 364 in Group A and 62 in Group B. Permanent hypoparathyroidism occurred in 3 (0.82%) patients from Group A and in 26 (41.94%) from Group B (p < 0.001). When iPTH levels were < 4.6 pg/mL on the first postoperative day the sensitivity for the prediction of permanent hypoparathyroidism was 89.66%, the specificity was 90.93%, the positive predictive value (PPV) was 41.94%, the negative predicitive value (NPV) was 99.18% and the accuracy was 90.85%. An iPTH value < 4.6 pg/mL on the first postoperative day following total thyroidectomy has proven to be a good parameter for early identification of patients at high risk for permanent hypoparathyroidism. Moreover, we want to underline that in our experience no patient with an iPTH level > 6.5 pg/mL developed this complication.

SAT-354 Isolated Hypoparathyroidism: A Rare Initial Manifestation of Hereditary Hemochromatosis (HH)

Background:We present a case of hypoparathyroidism diagnosed in a patient as initial manifestation of hereditary hemochromatosis. As per our literature search, it is very rarely reported as an isolated abnormality in HH.Case:A 27 year old male with history of seizure disorder, well controlled on Oxcarbazepine, referred for evaluation of chronic hypocalcemia. His PMH includes cerebral palsy, with good functional capacity and mild cognitive impairment. He denied muscle spasm, perioral numbness, bone pain, muscle weakness or fracture. He was taking calcium carbonate 600mg bid and vitamin D 50,000 IU q2monthly.There was no family history of any Ca disorders. Physical exam was unremarkable.Laboratory evaluation revealed Ca levels ranging from 7.6 to 8.5mg/dl with intact PTH values ranging from 11 to 22pg/ml. His ionized calcium was also low. Patient’s 24 hr urinary Ca was 122mg/24hrs. In this case, he did initially have hypomagnesemia and vitamin d deficiency, which could potentially explain low calcium. But even after supplementing Vitamin D and Mg, patient’s Ca remained low. His kidney function was normal. Hemoglobin was in range of 14-15g/dl. To further evaluate the cause of hypoparathyroidism, iron saturation and iron levels were also sent. His iron saturation % was high at 89% with iron level of 286 ug/dl. His ferritin was 224 ng/ml and TIBC was 265 ug/dl. A sample was sent for genetic analysis to rule out hemochromatosis. Homozygous mutations in C282Y gene were found. A diagnosis of hereditary hemochromatosis was made. His other entire hormonal axis was intact. In this case, patient’s hypoparathyroidism is likely an initial manifestation of his HH.Discussion:Hereditary Hemochromatosis (HH) is a genetic disease characterized by an excessive (unregulated) entry of iron into the bloodstream with increased iron deposition in the parenchymal cells of a variety of organs leading to their failure. A defect in the hemochromatosis gene (HFE) is the most common form of HH, also known as the classic form or type 1 HH, where the principal mutation is represented by a substitution of tyrosine for cysteine at position 282 of the HFE gene (C282Y) as seen in our case. According to the genetic forms, the clinical manifestation usually ranges from simple biochemical abnormalities to severe organ damage and disease such as liver cirrhosis, arthritis, DM, cardiomyopathy and hypogonadism.There are reports of hypoparathyroidism from iron overload seen in thalassemia patients and patients who receive long term blood transfusions. In our literature review, this is the first documented case of HH initially manifesting as hypoparathyroidism. As HH is not uncommon in Caucasians, the work up for hemochromatosis as a possible cause of endocrinopathies should be kept in the differential diagnosis. It will help in early diagnosis & treatment which can reverse the effects of the disease leading to better outcomes.

Mental Effects of Excess Parathyroid Hormone in Hemodialysis Patients: A Possible Role for Parathyroid 2 Hormone Receptor?

Depression as measured by the kidney disease quality of life (KDQOL) form is known to be an independent risk factor for mortality dialysis patients. Excess parathyroid hormone (PTH) has long been associated with neuropsychiatric disturbances. Those psychiatric complications are currently attributed to hypercalcemia with very little evidence; however, with the discovery of the parathyroid hormone 2 receptor (PTH2R) in the brain which can be activated by PTH, PTH2R might indicate a direct effect of PTH. As secondary and tertiary hyperparathyroidism is common in dialysis patients where the serum calcium is low or normal, we chose to investigate a possible relationship between PTH levels and depression in dialysis patients. This was a matched pair observational study with 10 patients with intact PTH values above 1000 pg/mL who were matched with 10 patients who had PTH values less than 400 pg/mL for the presence of diabetes, years on dialysis, duration of dialysis time, Kt/V, hemoglobin, and 25 OH vitamin D levels, as well as intravenous iron and erythropoietin administration. The Kidney Disease Quality of Life questionnaire (KDQOL-36) scores and patient Health Questionnaire scores were analyzed during that time. All variables underwent tests for normality and matched pair t-test. All subscales of the KDQOL-36 were worse in the high PTH group with the effect on daily life reaching P = 0.01 and the burden of disease and symptoms both reaching P = 0.02. PTH and PTH2R may be appropriate targets for investigations to improve the quality of life in hemodialysis patients.

Measurement of intact parathormone after one hour of total thyroidectomy: a predictor of symptomatic hypocalcemia

Background: Hypocalcemia is one of the most common complications of thyroidectomy. Hence, parathyroid hormone (PTH) measurement can be used to predict patients at risk for developing significant postoperative hypocalcaemia after thyroidectomy. The present study was conducted with the objective to find out whether there is any correlation between intact PTH value and patients developing symptoms of hypocalcemia after total thyroidectomy and to determine the threshold value of 1 hour post total thyroidectomy (intact PTH level) that can identify those at high risk for developing symptomatic hypocalcemia.Methods: Study involved determination of serum calcium, creatinine and albumin preoperatively, serum intact PTH, 1 hour after completion of total thyroidectomy (i.e. after the closure of skin incision), and serum calcium levels 6, 24 and 48 hours postoperatively. Clinical findings suggestive of hypocalcaemia were also watched for and recorded. Symptomatic signs and/or symptoms were recorded. The patients were followed up for 3 days post operatively and the lowest recorded serum calcium was taken into account. The results were tabulated and entered in Microsoft excel and analysed with spss 17 statistical software.Results: 26% of the study population developed hypocalcemia. Intact PTH was found to be lower in patients who developed symptoms of hypocalcemia. There was a statisticantly significant correlation between the two groups. A one-hour Intact PTH value of 14 pg/ml was found to have high sensitivity (92.3%) and specificity (91.9%).Conclusions: Hypocalcemia is the most common complication after total thyroidectomy. Intact PTH measurement one hour after total thyroidectomy can be used to predict the patients who will develop hypocalcemia after total thyroidectomy. Therefore, patients having low one-hour intact PTH value could be started on calcium supplementation and those having high PTH could be safely discharged early.

Treatment of Persistent Hypercalcemia and Hyperparathyroidism With Cinacalcet After Successful Kidney Transplantation

IntroductionHypercalcemia caused by persistent hyperparathyroidism after successful kidney transplantation (KT) is a common problem and may negatively affect graft function, bone metabolism and the cardiovascular system. Cinacalcet is a novel, available tool to control hypercalcemia after KT. The aim of the study was to examine the efficacy of cinacalcet in lowering calcium in KT recipients with persistent hypercalcemia owing to hyperparathyroidism. MethodsIn this retrospective observational study, we analyzed 30 patients with persistent hypercalcemia >10.8 mg/dL. All patients in the study were started on cinacalcet at different points after KT, with the mean time of 43 ± 37 months. The initial dose of 30 mg/d was adapted progressively based on serum calcium levels. ResultsDuring the observation period, graft function in all patients was stable (estimated glomerular filtration rate [Chronic Kidney Disease Epidemiology Collaboration formula] 64 ± 25 mL/min/1.73 m2). The mean baseline calcemia was 11.9 ± 0.7 mg/dL, the intact parathyroid hormone value was 490 ± 228 pg/mL and phosphorus concentration was 2.2 ± 0.5 mg/dL. Treatment with cinacalcet resulted in a significant decrease in serum calcium level (mean, 9.9 ± 0.7 mg/dL; P < .001), a reduction in intact parathyroid hormone level (308 ± 199 pg/dL; P < .001), and an increase in phosphorus concentration (mean, 2.8 ± 0.6 mg/dL; P < .001). In 5 females, gastrointestinal side effects were observed, requiring withdrawal of cinacalcet in 1 case. ConclusionsCinacalcet administered after KT seems to be an effective option for the management of persistent hypercalcemia owing to hyperparathyroidism with satisfactory tolerability and may be considered as a therapeutic alternative to surgical parathyroidectomy or as a bridging therapy to parathyroidectomy.

Low parathyroid hormone levels after parathyroidectomy reduce cardiovascular mortality in chronic hemodialysis patients.

The aim of the study is to elucidate whether parathyroid hormone (PTH) levels after parathyroidectomy affect the prognosis of patients with secondary hyperparathyroidism. Two hundred and ninety-five patients, who underwent PTx without autotransplantation from July 1998 to December 2011, were divided into the low (n=148) and high (n=147) PTH groups, using the median value of each mean value of intact PTH after surgery (16.6pg/mL). After observation for 5.00years, we evaluated demographic factors, influences of postoperative mineral metabolism, magnitude of uremia, and vitamin D receptor activators on their prognosis, with the multivariate Cox proportional hazard model. While overall survival rates in the high and low PTH groups were 54.9 and 74.2%, respectively (P=0.1500), cardiovascular survival rates were 71.6 and 94.4%, respectively (P=0.0256). The hazard ratio for cardiovascular mortality in the high PTH group (≥16.6pg/mL) was 3.132 (P=0.0470), and those in groups with the median age more than 59years and with cardiovascular disease were 2.654 (P=0.0589) and 3.377 (P=0.0317), respectively. The intact PTH level 6days after surgery and the mean postoperative intact PTH value showed a strong correlation (Spearman ρ=0.9007, P<0.0001, y=0.4725x+30.395, R 2=0.51798). The present study suggests that maintaining low PTH levels after parathyroidectomy reduces cardiovascular mortality and improves the prognosis. Total parathyroidectomy (more than 4 glands) without autotransplantation seems to be one of the treatment options for managing severe secondary hyperparathyroidism.

Dietary calcium intake influences the relationship between serum 25-hydroxyvitamin D3 (25OHD) concentration and parathyroid hormone (PTH) concentration

ObjectivesTo investigate whether dietary calcium intake will modify the relationship between serum 25-hydroxyvitamin D3 (25OHD) with intact serum parathyroid hormone (PTH) concentrations in apparently healthy Indian adolescents.Study designCross-sectional study.Setting and...

Serum Magnesium and Mortality in Hemodialysis Patients in the United States: A Cohort Study

Low serum magnesium levels in patients with kidney disease have been linked to increased mortality. This study investigated whether similar associations existed in maintenance hemodialysis (HD) patients. Cohort study. All Fresenius Medical Care North America in-center HD patients with available serum magnesium measurements were studied. The initial exploratory study in 21,534 HD patients evaluated associations among serum magnesium level, dialysate magnesium concentration, and mortality from April 2007 through June 2008. The follow-up study in 27,544 HD patients evaluated associations between serum magnesium levels and mortality over 1 year (January through December 2008). The primary predictor was serum magnesium level, with adjustment for case-mix (age, sex, race, diabetes, and dialysis vintage and additionally for follow-up study: body surface area and vascular access) and laboratory variables (albumin, hemoglobin, phosphorus, equilibrated Kt/V, potassium, calcium, and intact parathyroid hormone values). Primary outcome variable was 1-year mortality risk, evaluated using Cox proportional hazards models. Among 21,534 HD patients in the exploratory study, there were 3,682 deaths. Higher dialysate magnesium level was associated with higher serum magnesium level (R=0.22; P<0.001). Patients with the lowest serum magnesium levels (<1.30 mEq/L) were at highest risk for death (HR, 1.63; 95% CI, 1.30-1.96; reference serum magnesium, 1.60-<1.90 mEq/L). Among 27,544 HD patients in the follow-up study, there were 4,531 deaths. In Cox proportional hazards models, there was a linear decline in death risk from the lowest to the highest serum magnesium category, with the best survival at serum magnesium levels≥ 2.50 mEq/L (HR, 0.68; 95% CI, 0.56-0.82). However, risk estimates were attenuated with case-mix and lab adjustment. This pattern was consistent within diabetes subgroups and for cardiovascular or noncardiovascular causes of death. Observational study with cross-sectional serum magnesium measurements and no information for oral magnesium intake. Elevated serum magnesium levels > 2.10 mEq/L were associated with better survival than low serum magnesium levels< 1.30 mEq/L in HD patients. Prospective studies may determine whether manipulation of low serum magnesium levels affects survival.

Effect of Switching to Nocturnal Thrice‐Weekly Hemodialysis on Clinical and Laboratory Parameters: Our Experience

Long or frequent hemodialysis schedules are reported to improve clinical outcomes. We report here our experience with an in-center, nocturnal, thrice-weekly hemodialysis program. We retrospectively analyzed the effect of switching 10 patients (8 male, age 45 ± 11 years, renal replacement therapy vintage 12 ± 8 years) from regular, 4-5 h, thrice-weekly hemodialysis to 8 h nocturnal, in-center hemodialysis as regards dialysis efficiency, chronic kidney disease-metabolic and bone disease (CKD-MBD) parameters, blood pressure, and anemia. With more intense dialysis, the mean predialysis creatinine and urea decreased significantly (1092 ± 195 vs. 961 ± 154 μmol/L, P < 0.01 and 30.8 ± 4.6 vs. 25.5 ± 2.9 mmol/L, P < 0.01), while the decrease in potassium was insignificant (5.9 ± 0.7 vs. 5.6 ± 0.5 mmol/L), but in 3/10 patients, dialysate potassium was increased. Three months after starting nocturnal hemodialysis, no significant influence on pre-dialysis blood pressure was observed (143/80 vs. 140/80 mmHg), but antihypertensive medications were reduced in two patients. The mean dry weight reduced (74 ± 12 to 72 ± 12 kg) and the mean ultrafiltration increased insignificantly (3123 ± 1174 to 3434 ± 1341 mL). Serum calcium was stable, while phosphate reduced insignificantly (1.5 ± 0.5 to 1.2 ± 0.2 mmol/L), but 6/10 patients were able to discontinue phosphate binders, the dose was reduced in one, and phosphate was added to dialysate in 3/10 patients. Intact parathyroid hormone values were within the target range, except in patients post-parathyroidectomy. There were no differences in hemoglobin (121 ± 6 vs. 122 ± 8 g/L), and the mean epoetin dose decreased insignificantly (5950 ± 3947 vs. 5250 ± 4238 IU/week). To conclude, improved phosphate and potassium control and reduction in phosphate binders were observed after switching to nocturnal hemodialysis. There was an insignificant reduction of epoetin dose and antihypertensive medications.

A case report of disabling bone pain after long-term kidney transplantation

A 77-year-old man, who received a renal transplant 13 years before for IgA glomerulonephritis, was referred after he developed bilateral mid-tibial aching pain that did not improve with simple analgesia. He had recently been changed from low-dose cyclosporine to tacrolimus, but the pain did not improve when this was reversed. He had a history of focal prostatic adenocarcinoma, cryptococcal lung infection, osteoporosis treated with alendronate for 2 years and multiple squamous cell carcinomas, including one requiring left neck dissection and radiotherapy. Upon physical examination, he had gouty tophi and marked bilateral tibial tenderness but had no other clinical findings. Laboratory investigations included an elevated intact parathyroid hormone value of 7.9 pmol/L (1.6 to 6.9), bone specific alkaline phosphatase of 22 µg/L (3.7 to 20.9), urinary deoxypyridinoline/creatinine ratio of 7.2 nmol/mmol (2.5 to 5.4) and C-reactive protein. Chest X-ray and tibial X-rays were normal, but there was marrow oedema and a prominent periosteal reaction on magnetic resonance imaging. A radionuclide bone scan showed increased symmetrical, linear uptake in both tibiae and the left femur, and uptake was also noted in both clinically asymptomatic humeri. Tibial bone biopsy disclosed small deposits of poorly differentiated metastatic cancer and a follow-up chest CT revealed a lung lesion. It was concluded that the bone pain and periostitis was caused by primary lung cancer with metastatic disease to bone, and an associated hypertrophic osteoarthropathy.

Quels marqueurs osseux chez les patients hémodialysés : phosphatases alcalines osseuses ou ß-CrossLaps ?

BackgroundBone turnover (BT) abnormalities are frequently observed in patients with chronic kidney disease. Bone biopsy remains the gold standard for diagnosis; however, its invasive nature has led to its decreased utilisation. The serum parathyroid hormone (PTH) level is not a reliable bone marker (BM) for BT assessment. The latest international recommendations suggest the use of total alkaline phosphatase (t-ALP) or bone-specific alkaline phosphatase (b-ALP), but not ß-CrossLaps (CTX). We compared b-ALP, t-ALP, and CTX levels in patients on haemodialysis (HD). MethodsAll HD patients at a single institution following a standard 3×4 to 3×5hours schedule were included in the study, provided they were free from liver disease. Serum intact PTH, t-ALP, b-ALP, and CTX values were compared at baseline and after 18months of treatment. A kinetic study was performed for pre- and postdialysis CTX values over a 2-week period. We described the longitudinal evolution of these BMs in two typical patients. ResultsA total of 98 patients on HD (46% female) were evaluated. The mean age was 69.8±11years and the mean duration of dialysis was 54.4±61months. At baseline, CTX (2.1±1μg/L) correlated well with b-ALP (18±11μg/L; r=0.64; P<0.001) and PTH (221±165pg/mL; r=0.62; P<0.001). The changes in these values at 18months were also correlated (ΔCTX compared with Δb-ALP: r=0.51; P<0.001; Δb-ALP compared with ΔPTH: r=0.37, P<0.01). b-ALP and t-ALP (245±132U/L) were closely correlated (r=0.78), as was their variation over 18months (r=0.67), but t-ALP did not correlate with PTH, and correlated poorly with CTX (r=0.38). The CTX reduction ratio during standard dialysis was approximately 70 to 75% over each session, although predialysis values remained stable. ConclusionIn HD patients, mean CTX values are five times higher than the normal range. CTX appears to be an alternative to b-ALP for assessing BT. b-ALP remains the standard BM, despite being expensive, infrequently available in many laboratories, and not useful for patients with liver disease.

Intermittent Dosing of Cinacalcet is also Effective in Treating Secondary Hyperparathyroidism in Hemodialysis Patients

Background: The calcimimetic, cinacalcet hydrochloride acting on the calcium-sensing receptors is being used quite often in the management of secondary hyperparathyroidism (SHPT). It is given in daily dose of 30-180 mg but there have not been enough comparative trials with intermittent dosing schedule. Aim: To evaluate effectiveness of daily cinacalcet hydrochloride dose and its 3 weekly doses in reducing serum intact PTH levels and relative concentrations of calcium and phosphorous in patients with end stage renal diseases (ESRD) with SHPT on maintenance hemodialysis (HD). Material and methods: Chronic kidney disease (CKD) patients (n=29) who were receiving daily dose (OD) of cinacalcet for SHPT for I year were shifted to an intermittent dosing regimen of cinacalcet at the end of each hemodialysis session (HD), 3 times per week (study patients). After taking baseline measurements of PTH, its monthly assessment along with serum calcium, phosphorous and alkaline phosphatase level estimations at 1, 3, 6, 9 and 12 months were then compared with the baseline levels. Results: Overall the mean intact PTH value was 174.2 + 16.8 pg/ml at the end of one year treatment prior to the study, while receiving a mean dose of 83.7 ± 11 mg cinacalcet OD. This controlled value of PTH did not show any statistically significant difference over the next 12 months when the study patients were given intermittent dosing (3/ week) at the end of each hemodialysis session. Similarly the calcium values did not change to a significant level in the study subjects, although the serum phosphorus showed a significant rise at the end of the study period (p=0.003). Conclusion: Cinacalcet effectively controls parathyroid hormone levels and uncontrolled secondary hyperparathyroidism both when given daily and intermittently (3/week). Frequent monitoring and adequate replacement with calcium and vitamin D sterols prevent hypocalcemia with cinacalcet therapy. Thus intermittent dosing of cinacalcet is an excellent cost-effective therapeutic option in HD patients with SHPT. In addition, it improves drug compliance.

High prevalence of vitamin D deficiency among healthy Saudi Arabian men: relationship to bone mineral density, parathyroid hormone, bone turnover markers, and lifestyle factors

In this cross-sectional study, the prevalence of vitamin D deficiency [serum 25-hydroxyvitamin D (25(OH)D) <50 nmol/L] was 87.8% among Saudi Arabian men. There was a linear inverse relationship between serum 25(OH)D and intact parathyroid hormone (PTH) levels, but without a threshold of 25(OH)D at which intact PTH values plateaued. Vitamin D insufficiency and/or deficiency has now reached epidemic proportions and has been linked to low bone mineral density (BMD), some lifestyle factors, and obesity in adults. This relationship is not well documented in Saudi Arabian men. This study examines the relationship between vitamin D status, intact parathyroid hormone (intact PTH), and lifestyle factors among Saudi Arabian men. This cross-sectional study involved 834 men aged 20-74 years living in Jeddah area who were randomly selected and medically examined. Men had their BMD (lumbar spine (L1-L4) and neck femur), 25(OH)D, intact PTH, and other parameters measured according to detailed inclusion criteria. Deficiency (25(OH)D<50 nmol/L) and insufficiency (≥50-75 nmol/L) were present in 87.8% and 9.7%, respectively. Deficiency was common among older and obese men with no education and sedentary lifestyle sampled during summer and spring. Serum 25(OH)D showed an inverse linear relationship with intact PTH, but there was no threshold of serum 25(OH)D at which PTH levels plateaued. There was a positive correlation between BMD values at both lumbar spine (L1-L4) (P < 0.023) and neck femur (P < 0.036) and serum 25(OH)D levels, respectively. Functionally significant vitamin D deficiency affects BMD and bone turnover markers among Saudi Arabian men and is largely attributed to older age, obesity, sedentary lifestyle, no education, poor exposure to sunlight, smoking, and poor dietary vitamin D supplementation. The data suggest that an increase in PTH cannot be used as a marker for vitamin D deficiency.

Vitamin D status and bone health in healthy Thai elderly women

Objective The prevalence of hypovitaminosis D varies in different countries. Therefore, the current study was designed to assess vitamin D status and bone health in elderly women in Thailand, which is situated near the equator. Methods This cross-sectional study was performed in 446 healthy women aged 60–97 y. Results Serum 25-hydroxyvitamin D (25(OH)D) was 67.6 ± 15.7 (mean ± SD) nmol/L. Daily calcium intake was 309.5 ± 147.2 mg/d. Serum 25(OH)D levels tended to decline with bone mineral density (BMD) status. Based on functional health-based reference values, plasma-intact parathyroid hormone began to rise below serum 25(OH)D level 70 nmol/L and increase significantly when serum 25(OH)D was ≤60 nmol/L. Thirty-two percent of elderly women had 25(OH)D insufficiency (≤60nmol/L). There was no trend toward a decrease in the concentration of serum 25(OH)D with age ( r = −0.078, P = 0.10) and no significant inverse relationship with plasma intact parathyroid hormone values ( r = −0.079, P = 0.097). However, a positive relationship was observed between serum 25(OH)D level and femoral neck BMD ( r = 0.156, P = 0.001) but not lumbar spine L 2-L 4 BMD ( r = 0.093, P = 0.050). In addition, BMD at the femoral neck but not lumbar spine of the vitamin D insufficiency group was significantly lower than that of the vitamin D sufficiency group. Conclusion The optimum level of serum 25(OH) value in Thai elderly women should be higher than 70 nmol/L. Vitamin D insufficiency is observed in one-third of elderly women in Bangkok.

Calcium-Corrected Intact PTH: A Clinically Useful Parameter for Quantifying Parathyroid Function in Patients Undergoing Hemodialysis

Background/Aims: Serum parathyroid hormone (PTH) concentration provides a rough index of the severity of secondary hyperparathyroidism (SHPT) due to chronic renal failure. Since serum PTH inversely related to calcium (Ca) level, we attempted to create a new index based on the relationship. Methods: Our subjects were 70 patients undergoing maintenance hemodialysis (HD) in a single facility. Using multiple pairs of serum Ca corrected for albumin (cCa) and intact PTH (iPTH) values drawn simultaneously, we determined the steepest slope of cCa-iPTH relationship for each individual patient to get a line closely resembling the cCa-PTH sigmoidal curve. Results: Based on the slopes, the following equation was obtained: iPTH2 = iPTH1 + (cCa1 – cCa2) × (43 + 0.47 × iPTH1), where the PTH values at any 2 arbitrary values of cCa1 and cCa2 were assumed to be iPTH1 and iPTH2, respectively. When ‘corrected PTH’ is defined as the predicted value of iPTH at cCa = 9.0 mg/dl, its correlation was better than iPTH with the total volume of the parathyroid glands estimated by ultrasonography. Similar results were found in 30 parathyroidectomized patients at other facilities. Conclusion: ‘Corrected PTH’ may represent a useful parameter for assessing the severity of SHPT from single determinations of cCa and iPTH drawn at the same time.

Minimally invasive surgery for primary hyperparathyroidism with or without intraoperative parathyroid hormone monitoring

We analyzed the utility of intraoperative parathyroid hormone (IOPTH) monitoring in minimally invasive surgery for primary hyperparathyroidism (pHPT). The subjects were the 167 consecutive patients with pHPT performed initial operation with or without IOPTH between January 2000 and December 2006. Patients were divided into 2 groups. A group who underwent surgery without IOPTH monitoring (Group 1; n=87), and a group who underwent surgery with IOPTH monitoring (Group 2; n=80), in which IOPTH was measured at 5, 10, 15 minutes after excision of the abnormal parathyroid gland. Criterion for evaluation as a cure was a drop in intact PTH level of 50% or more from the preoperative baseline value. The overall cure rate in Group 1 was 93.1%. An enlarged parathyroid gland that was consistent with the results of a preoperative imaging study was found in 84 patients (96.6%). The overall cure rate in Group 2 was 97.5%. In 7 of the patients, there was no drop of 50% or more at any of the 3 points in time measured. Two of these patients were found to have had double adenomas, one on each side, during the initial surgery. Three others were eucalcemic and had normal intact PTH values after surgery, and the remaining 2 patients had persistent disease. Although preoperative localization studies are accurate and essential, IOPTH monitoring improves the cure rate of minimally invasive parathyroidectomy. IOPTH monitoring is a valuable adjunct to achieve adequate intraoperative decision-making, recognizing and resecting additional image-negative hyperfunctioning lesions.

Adherence to K/DOQI Bone Metabolism Guidelines

Guidelines for the treatment of patients with chronic kidney disease recommend laboratory testing of markers of bone metabolism, including intact parathyroid hormone, calcium, and phosphorus. The authors sought to evaluate the concordance of contemporary clinical practice with treatment recommendations. Trends were evaluated (2002 to 2005) in testing for bone metabolism in patients with chronic kidney disease, and the relation between bone metabolism markers, severity of chronic kidney disease, and cardiovascular hospitalizations were examined. Retrospective cohort. Large United States health-maintenance organization. Chronic kidney disease. Little variation was found in testing rates over time. Testing frequency was positively correlated with severity of kidney disease, referral to nephrology, and test type (annual testing was most likely for intact parathyroid hormone, and least likely for calcium). Patients with higher intact parathyroid hormone values had a greater risk of cardiovascular-related hospitalization; after adjusting for potential confounders, those with an intact parathyroid hormone value of 200 and greater had a relative risk of 2.16 (95% confidence interval, 1.09 to 4.29). This study supports the hypothesized association between disorders of bone metabolism and cardiovascular disease, but it does not address whether increased testing for disorders of bone metabolism will improve outcomes for patients with chronic kidney disease. Nor does our analysis imply that controlling parathyroid hormone will prevent cardiovascular hospitalizations. Future studies should more fully explore those critical clinical questions.