Hyperparathyroidism prevention

Determine if the patient requires medical intervention to prevent the development of or treatment for secondary hyperparathyroidism. 

Calcium should be ingested in adequate amounts to prevent secondary hyperparathyroidism and bone destruction. Although calcium increases BMD, fracture prevention is minimal. It should be combined with vitamin D and osteoporosis medications when needed. 

Zemplar (paricalcitol) injection is a synthetically manufactured selective vitamin D receptor activator (SVDRA) indicated for the prevention and treatment of secondary hyperparathyroidism associated with chronic kidney disease (CKD) stage 5. The U.S. Food Drug Administration (FDA) approved a capsule form of Zemplar for development to satisfy a need for an oral formulation. The objective of study M04-693 was to assess the bioequivalencies of several dosage strengths of paricalcitol capsules under fasting conditions. 

Paricalcitol is a synthetically manufactured analogue of calcitriol. It is indicated for the prevention and treatment of secondary hyperparathyroidism in chronic kidney disease. Cinacalcet, a drug that acts as a calcimimetic, can be added if the effects on PTH levels are isufficient. 

Q9 The hypercalcaemia which occurs in hyperparathyroidism may be reduced by administration of a loop diuretic such as furosemide, which helps calcium excretion. Bisphosphonates, which prevent bone resorption and so reduce calcium release from bone, can be used to treat hypercalcaemia associated with malignancies. Calcitonin may also be useful in treating the hypercalcaemia associated with cancer, as it reduces calcium levels both by attenuating its renal reabsorption and by increasing calcium deposition in bone. 

The U.S./Canadian report (Institute of Medicine, 1997) discussed requirements only in terms of bone density and maintenance of a plasma concentration of calcitriol above that associated with elevated parathyroid hormone and alkaline phosphatase. Vieth (1999) noted that intakes above 5 /xg per day are required to prevent osteoporosis (Section 3.4.3) and secondary hyperparathyroidism, and suggested that normal sunlight exposure may provide the... 

Hyperparathyroidism and aluminium hydroxide lead to aluminium-related bone disease however, total parathyroidectomy does not lead to failure of aluminium mobilization after renal transplantation. This man had satisfactory graft function, and the aluminium excretion that was achieved by deferoxamine suggests that the renal transplant was not the limiting factor for the mobihzation of aluminium. The most likely explanation was that he developed adynamic bone through a combination of vitamin D deficiency, hypoparathyroidism, and aluminium deposition. Vitamin D supplementation failed to prevent the osteodystrophy on its own. When aluminium chelation therapy was used, bone healing occurred and his symptoms improved. 

Of 19 chronic hemodialysis patients taking a combination of alfacalcidol and calcitriol for 12 months, six had increased bone resorption, six had reduced bone resorption, and seven had no change. Histologically documented aggravation of hyperparathyroidism was associated with a statistically significant increase in plasma concentrations of phosphate and parathyroid hormone. The administration of vitamin D analogues may therefore be either beneficial or noxious depending on whether or not induced hyperphosphatemia is adequately prevented (55). 

Intermediate concentrations are seen in low-turnover adynamic (aplastic) disease and early osteitis fibrosa. Considerable overlap in intact PTH concentrations is apparent among the various forms of renal osteodystrophy. In dialysis patients, cut-points ( decision levels ) of less than 100 or 150 pg/mL and greater than 250 to 300 pg/mL have been suggested for distinguishing patients with low-turnover and high-turnover bone disease, respectively. A reasonable therapeutic goal for intact PTH (first generation) concentrations is two to four times the upper limit of the reference interval to prevent parathyroid-suppressed, adynamic, and hyperparathyroid bone diseases. ... 

Although the Institute of Medicine recommends 400 units daily if under 71 years old and 600 units daily if 71 years or older, many prescribers recommend higher doses since Institute of Medicine-recommended doses do not prevent hyperparathyroidism in everyone, which requires attaining 25(OH) vitamin D concentrations of 30 to 40 ng/mL. The relationship between intake and 25(OH) vitamin D concentration is curvilinear. Vitamin D 400 units produced average 25(OH) vitamin D concentrations of 18 ng/mL. Vitamin D 1000 units per day for more than 3 months produced 25(OH) vitamin D concentrations of at least 30 ng/mL in 35% of subjects (range among all patients, 16 to 40 ng/mL), and 4000 units of vitamin D daily produced these concentrations in 88% of subjects (range, 28 to 50 ng/mL). Vitamin D... 

The administration of hydroxylated vitamin D metabolites may prevent the development of secondary hyperparathyroidism. There is a risk of hypercalcaemia with this treatment. Dietary restriction of protein, to reduce the formation of nitrogenous waste products, may give symptomatic improvement. A negative nitrogen... 

Other trials have shown an increased risk of falls and fractures with annual oral administration of high doses of vitamin D. Therefore, supplementation with more frequent, lower doses is preferred. Yet the optimal dosing schedule is unknown and needs further investigation. In order to treat age-associated secondary hyperparathyroidism and to prevent osteoporotic fractures, a daily dose of 1000-1200 mg calcium and 800 lU vitamin D is recommended in elderly or individuals on chronic glucocorticoid therapy. 

The true secondary hyperparathyroidism of chronic renal failure (CRF) has been extremely difficult to treat by clinicians because of high Pi and PTH concentrations in this condition. Traditional treatment includes the use of binders (chemical) to prevent Pi absorption from the small intestine. In recent years, a calcium-sensing receptor (CaR) in the parathyroid... 

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