Parathyroid Hormone

Objective  To determine the effects of menopause on bone-related variables in Indonesian women and to compare them with corresponding data in Caucasian Australian women.Design  A study of bone-related variables in women aged 45–55 years in Jakarta compared with corresponding historical data from Caucasian Australian women.Measurements  Dietary intakes, bone mineral density (BMD) and calcium-related variables in blood and urine.Results  Dietary calcium, phosphorus and protein intakes were significantly lower in the women from Jakarta than in those from Adelaide (all P < 0·001), probably because of lower milk consumption, but energy intake was similar in the two cities. Indonesian women were shorter and lighter than Australian women (P < 0·001) but had a comparable body mass index (BMI). The Indonesians also had a lower spinal BMD than the Australians but this was accounted for by the differences in height and weight between the two populations. The differences in serum and urinary calcium and phosphate and serum alkaline phosphatase across the menopause were comparable in Indonesian and Australian women but creatinine excretion was 25% lower in Jakarta than in Adelaide (P < 0·001) and this was probably sufficient to account for higher ratios of some urinary solutes to urinary creatinine in the Indonesians. Serum 25-hydroxyvitamin D (25OHD) levels were significantly lower (P < 0·001) and serum PTH levels significantly higher (P = 0·0045) in Jakarta than in Adelaide.Conclusions  The differences in bone-related biochemical variables across the menopause were similar in the two populations, but calcium and protein intake and urine creatinine were lower in Indonesian than in Australian women. Serum 25OHD was lower and PTH higher in the Indonesian women, probably because of their darker skin, their practice of avoiding direct sunlight and the heavy atmospheric pollution in Jakarta.

Abstract: Minimally invasive parathyroidectomy is an accepted treatment option for primary hyperparathyroidism. The need for intraoperative parathyroid hormone assays (iPTH) to confirm adenoma removal remains controversial. We studied minimally invasive radio-...

Amyloid deposits are common in various tissues as a consequence of misfolded proteins. However, secretory protein and peptides are often stored in membrane coated granules as functional amyloids. In this article, we present a detailed characterization of in vitro generated amyloid fibrils from human parathyroid hormone (hPTH(1-84)). Fully mature fibrils could be obtained after a short lag phase within less than one hour at 65°C. These fibrils showed all characteristic of a cross-β structure. Protease cleavage combined with mass spectrometry identified the central region of the peptide hormone involved in the fibril core formation. EGCG, an inhibitor of amyloid fibril formation, showed binding to residues in the peptide monomers corresponding to the later fibril core and thus explaining the inhibition of the fibril growth. Conformational and dynamic studies by solid-state NMR further corroborated the cross-β core of the fibrils, but also identified highly mobile segments with a rando...

The aim of the present study was to evaluate the effect of hemodialysis and renal failure on serum bone markers. Serum total alkaline phosphatase (TAP), procollagen type I aminoterminal propeptide (PINP), and Β-carboxyterminal telopeptide of type I collagen (Β-CTX), as well as intact parathyroid hormone (iPTH), creatinine, and total protein were measured in 14 patients with endstage renal disease (ESRD) before and at 1, 2, and 4 h during a hemodialysis session, and at the same sampling interval in 6 renal transplant recipients. The results were compared to those obtained in 20 healthy adults. All patients showed increased baseline mean values of PINP, Β-CTX, and iPTH. Β-CTX differed significantly between hemodialysis patients and renal transplant recipients. TAP and Β-CTX were the only markers which correlated with iPTH (P ≪ 0.05) and creatinine values (P ≪ 0.001), respectively. Renal transplant recipients did not show significant variations in the evolution of mean values of bone markers throughout the study, whereas, during the dialysis period, all the bone markers analyzed in the study showed a significant change. The change differed depending on the marker considered: Β-CTX showed a significant decrease at the end of the session, TAP increased at this time and, although PINP showed an initial increase during hemodialysis, no significant changes were observed at the end of the session. We conclude that bone markers are significantly influenced by hemodialysis, especially serum TAP and Β-CTX. ESRD is associated with an increase in these bone markers, in some cases related to iPTH values and in others to glomerular function. These findings should be taken into account when evaluating bone markers in these patients.

The Mayo Clinic was one of the first institutions to develop an in-house rapid parathyroid hormone (PTH) assay that used homegrown antibodies to monitor plasma PTH levels during parathyroidectomy. This PTH assay is economical, but it requires highly trained technologists and an experienced laboratory director and it is difficult to perform in the operating suite. We sought a fully automated

Summary  Vitamin D deficiency is associated with increased fracture risk. The observational study aimed to investigate vitamin D status and supplementation in ambulatory patients. Only 20% of patients had optimal serum 25-hydroxyvitamin D [25(OH)D] levels. Commonly recommended dosages were insufficient to achieve clinically relevant increase of 25(OH)D levels. Higher dosages were safe and effective under clinical practice conditions. Introduction  Vitamin D deficiency

The epidemiological and clinical profiles of primary hyperparathyroidism (PHPT) have changed markedly over the past few decades. PHPT is now one of the most frequent endocrine disorders in clinical practice, with prevalence increasing with age. The clinical presentation of PHPT has progressively shifted from the classic form, with kidney stones, overt bone disease, and marked hypercalcemia, to a nearly or completely asymptomatic disease. Finally a fruste form of PHPT, normocalcemic hyperparathyroidism (NCPHPT), is increasingly encountered with its diagnostic and therapeutic challenges. The general consensus is that most patients with symptomatic PHPT, if surgery is not contraindicated owing to comorbidities, should be referred for parathyroidectomy (PTX), which remains the only curative treatment. On the other hand, the indication for PTX in asymptomatic and often clinically stable patients still remains controversial. Emerging evidence supports PTX even in asymptomatic patients owi...

Parathyroid hormone (PTH) measurement in serum or plasma is a necessary tool for the exploration of calcium/phosphorus disorders, and is widely used as a surrogate marker to assess skeletal and mineral disorders associated with chronic kidney disease (CKD), referred to as CKD-bone mineral disorders (CKD-BMD). CKD currently affects &gt;10% of the adult population in the United States and represents a major health issue worldwide. Disturbances in mineral metabolism and fractures in CKD patients are associated with increased morbidity and mortality. Appropriate identification and management of CKD-BMD is therefore critical to improving clinical outcome. Recent increases in understanding of the complex pathophysiology of CKD, which involves calcium, phosphorus and magnesium balance, and is also influenced by vitamin D status and fibroblast growth factor (FGF) 23 production, should facilitate such improvement. Development of evidence-based recommendations about how best to use PTH is lim...

In this paper, two cases with mucolipidosis type II (I-cell disease) (proven in one presenting newborn and presumed in an elder deceased brother) are presented. These infants showed severe skeletal changes with diffuse periosteal new bone formation in long bones and ribs, marked osteopenia, and resorption of scapula, clavicula, and mandible. There was also irregular demineralization of metaphyses of long

Background: Abnormalities in calcium and vitamin D metabolism are observed early after gastric bypass, whereas clinical or biochemical evidence of metabolic bone disease might not be detected until many years after the procedure. The aim of the present study was to evaluate the impact of bariatric surgery on bone metabolism determined on the basis of postoperative laboratory changes in calcium, phosphorus, magnesium, alkaline phosphatase and parathormone (PTH) levels. Methods: 110 patients submitted to Roux-en-Y gastric bypass (RYGBP) were followed after surgery, and the following parameters were determined: intact PTH molecule (PTHi; chemiluminescence), alkaline phosphatase (colorimetric method), ionic calcium (selective electrode), phosphorus and magnesium (colorimetric method). Results: Elevated serum PTHi levels were observed in 29% of the patients and hypocalcemia in 0.9% from the 3rd postoperative month and afterwards (3 to 80 months after surgery). Conclusion: There is a need for careful evaluation of bone metabolism and for routine calcium replacement after RYGBP.

Deflazacort was substituted for Prednisone (based on the equivalence 1 mg Prednisone equals 1.2 mg Deflazacort), during maintenance glucocorticoid therapy in 9 children, 5 with renal diseases and 4 with connective tissue or immunoproliferative disorders. Six patients received 0.26–0.35 mg/kg body weight (B.W.)/day and 3 0.48–1.2 mg/kg B.W. on alternate days, for 10–16 months. Except for a child with chronic juvenile arthritis, who was also unresponsive to Prednisone, the therapeutic effects of Deflazacort were excellent. Steroid side effects present in 8 patients decreased or disappeared. Plasma Ca, P, Mg, creatinine, alkaline phosphatase, iPTH(1-34), urinary excretion of Ca, cAMP, and TRP remained normal. Plasma iPTH(1-84) remained normal in 5 children; in the other 4 patients it increased from normal to slightly elevated values. On Deflazacort, plasma calcidiol concentrations were within the normal range in 6/8 patients prescribed daily doses of vitamin D2 (1,600–2,400 IU) or calcidiol (20 μg). Plasma 1,25(OH)2D levels monitored in 5 children were also normal. The osteoporosis, evaluated on the tibial cortico-diaphyseal ratio and the trabecular aspect of bone radiograms, present in 5 patients, persisted in 1 and improved in the others. On Deflazacort, statural growth proceeded normally in all subjects, with a modest acceleration of growth velocity in 3 children. These results seem encouraging for extending clinical trials with Deflazacort to the active phase of pediatric diseases requiring glucocorticoid.

Background: Primary hyperparathyroidism (PHPT) is a common clinical endocrine disorder. It is the most common
cause of hypercalcemia in the outpatient setting. This review presents a brief summary of the new trends of presentation,
diagnosis and management PHPT.
Data Sources: PubMed (National Library of Medicine) articles, and Memorial Library archives of the University of
Wisconsin System.
Conclusions: PHPT occurs at any age, but it is most commonly seen in people over the age of 50 years and
postmenopausal women. The current presentation of PHPT shifts from the classical symptomatic form to the
asymptomatic form; however, parathyroidectomy is still the treatment of choice for both symptomatic and asymptomatic
forms. In the past, bilateral neck exploration and intraoperative identification of all 4 parathyroid glands was the
standard of treatment, nevertheless, nowadays, with the introduction of the preoperative and intraoperative localization
techniques, the minimally invasive parathyroidectomy has evolved.

Aluminum toxicity is the presumed cause of aluminum-associated osteomalacia. In animal models, osteomalacia has been produced after a prolonged course of aluminum. In the present study, rats with renal failure received 20 mg intraperitoneal aluminum during a 2 day period. This model allows sequential observations in the development of osteomalacia. Rats were sacrificed and studied 5, 12, 25, and 40 days after aluminum administration. No differences were observed in serum calcium, phosphorus, or creatinine as a consequence of aluminum administration. Compared with control rats, parathyroid hormone was decreased at 12 and 25 days. A direct correlation was present between plasma and bone aluminum at 12 days (r = 0.92, p < 0.01), 25 days (r = 0.85, p < 0.005), and 40 days (r = 0.88, p < 0.001) but not 5 days after aluminum administration. Plasma aluminum peaked at 5 days (727 ± 89 μg/liter, mean ± SEM) and bone aluminum at 40 days (273 ± 40 μg/g). Aluminum had profound effect on bone histology. At 5 days there was a decrease in osteoblast surface and osteoid surface; at 12 days osteoblast surface and osteoid surface returned to normal but osteoclast surface decreased. Subsequently there was a progressive increase in osteoid surface and osteoid volume. Bone formation rate measured at 12, 25, and 40 days was decreased at these intervals.In conclusion, (1) high plasma aluminum may be directly toxic to the osteoblast; (2) progressive osteoid accumulation is secondary to matrix (osteoid) deposition, which exceeds the depressed bone formation rate; (3) the progressive decrease in plasma aluminum and increase in bone aluminum suggest that bone has a high affinity for aluminum but may have a relatively slow rate of uptake at any given time; (4) aluminum may directly decrease parathyroid hormone; (5) the correlation between plasma and bone aluminum suggest an exchange is present; and (6) aluminum toxicity may independently affect the osteoblast and bone mineralization.

BackgroundVitamin D insufficiency may increase the risk for cardio metabolic disturbances in patients with primary hyperparathyroidism (PHPT).ObjectiveTo analyze the vitamin D status and indices of the metabolic syndrome in PHPT patients and the effect of vitamin D supplementation after parathyroid adenomectomy (PTX).Design and methodsDouble-blinded, randomized clinical trial (ClinicalTrials.gov Identifier: NCT00982722) performed at Karolinska University Hospital, Sweden, April 2008 to November 2011. One hundred and fifty consecutive patients with PHPT (119 women) were randomized after PTX, 75 to oral treatment with calcium carbonate 1000 mg daily and 75 to calcium carbonate 1000 mg and cholecalciferol 1600 IU daily over 12 months. Changes in metabolic profile and ambulatory blood pressure (BP) were analyzed. Main outcome measures were changes in metabolic factors, BP, and body composition.ResultsThe 25-hydroxyvitamin D (25-OH-D)-level was &lt;50 nmol/l in 76% of the patients before...