Bailliere's clinical endocrinology and metabolism, 1988
Over the past decade important advances in our understanding of the pathophysiology and treatment... more Over the past decade important advances in our understanding of the pathophysiology and treatment of renal osteodystrophy have been made. In particular, the role of calcitriol deficiency in the genesis of hyperparathyroidism in early renal failure is now better understood. So too are the effects of aluminium on bone, and whereas the more florid aluminium related disease is now unusual the more subtle effects of aluminium are now being appreciated. There is still a major problem in the long-term treatment of hyperparathyroid bone disease. The reasons why parathyroid gland proliferation continues to occur on dialysis therapy require a better understanding of cellular events regulating hormone production and parathyroid cell replication. The case for early intervention with vitamin D is now strong but whether such an approach materially influences the long-term outcome is not yet established. Changes in the approach to treatment and in the modalities used for renal replacement therapy ...
1. The effects of three intravenous diphosphonates (etidronate, clodronate and aminohexane diphos... more 1. The effects of three intravenous diphosphonates (etidronate, clodronate and aminohexane diphosphonate) on phosphate homoeostasis were studied in 30 patients with Paget's disease of bone and in three patients with hypoparathyroidism. 2. In Paget's disease, all three diphosphonates induced significant increases in serum phosphate and renal tubular reabsorption of phosphate. This effect was most marked and persistent after etidronate, whereas in the clodronate- and aminohexane diphosphonate-treated patients the increases were less, of shorter duration and followed thereafter by significant decreases in serum phosphate and renal tubular reabsorption of phosphate. Unlike etidronate, both clodronate and aminohexane diphosphonate caused a significant reduction in serum and urinary calcium, with appropriate homoeostatic increases in immunoassayable parathyroid hormone. 3. Phosphaturic responses to infused parathyroid hormone were observed in two patients with etidronate-induced h...
Considerable confusion arises in defining osteomalacia in the presence of renal disease. There ar... more Considerable confusion arises in defining osteomalacia in the presence of renal disease. There are no radiographic or biochemical features which satisfactorily identify all patients with osteomalacia. Histological definitions need to distinguish increased amounts of osteoid due to defective mineralisation from that due to increased bone turnover, both of which may coexist in chronic renal failure. The pathogenesis of osteomalacia in renal failure is multifactorial and not always due to defective metabolism of vitamin D. Deficient production of 25-hydroxyvitamin D may occur because of nutritional privation or urinary losses in the nephrotic syndrome, but these are rare causes of osteomalacia in patients on haemodialysis treatment. It is not clear to what extent defective production of calcitriol, characteristic of end-stage chronic renal failure is causally related to osteomalacia, in part due to uncertainties as to whether vitamin D acts directly on bone to promote mineralisation or...
1. We studied the acute effects of intranasal and subcutaneous calcitonin in 40 patients with act... more 1. We studied the acute effects of intranasal and subcutaneous calcitonin in 40 patients with active Paget's disease of bone. Patients received a single dose of either 400 units of calcitonin delivered as a nasal spray, or 1, 10 or 100 units of subcutaneous calcitonin, or placebo. 2. Subcutaneous salmon calcitonin, administered at doses of 1, 10 and 100 units to nine patients with Paget's disease of bone, induced a dose-dependent fall in the serum calcium. This calcium-lowering effect was not seen with a second group of nine patients receiving placebo. 3. The lower doses of calcitonin had significant effects, and these were more pronounced in patients with lower rates of bone turnover. 4. Four hundred units of calcitonin administered as a nasal spray induced effects qualitatively similar to those seen with subcutaneous calcitonin, with an efficacy equivalent to approximately 30 units of subcutaneous calcitonin. 5. We conclude that the bioequivalence of calcitonin given by in...
5053 Background: Survival of men with testicular cancer is long due to successful therapeutic int... more 5053 Background: Survival of men with testicular cancer is long due to successful therapeutic intervention, which usually includes orchidectomy. Therefore, we studied the prevalence of osteoporosis in a single center cohort of long term survivors of germ cell cancer. Methods: In a cross-sectional study design, we studied 186 male patients with a mean age of 39.6 years (range 18.1–66.8), who were treated between 1977 and 2006 for germ cell cancer. 181 (97.3%) patients underwent an unilateral, 3 (1.6%) a bilateral orchidectomy and in 2 (1.1%) patients no orchidectomy but retroperitoneal or mediastinal tumor biopsy was performed to confirm the diagnosis. 141 (75.8%) patients received cisplatin-based combination chemotherapy for metastases or primary extra-gonadal tumor at a mean age of 29.4 years (range 14.2- 62.6). Between 2003 and 2006, bone mineral density (BMD) was measured at the lumbar spine and femoral neck by DXA and Z-scores calculated. Vertebral deformities were evaluated by ...
Nederlands tijdschrift voor geneeskunde, Jan 21, 2006
The management of osteoporosis has been dominated by the use of antiresorptive agents, such as bi... more The management of osteoporosis has been dominated by the use of antiresorptive agents, such as bisphosphonates and raloxifene, which have been shown to effectively reduce the risk of osteoporotic fractures. Teriparatide, a recombinant human parathyroid hormone, has recently become available. It has an altogether different action. Teriparatide is an anabolic agent that primarily stimulates bone formation. This leads to an increase in bone volume and the bone structure and microarchitecture is restored by an increase in trabecular thickness and an increase in the number of connections between trabeculae. Clinically relevant studies on teriparatide in postmenopausal women and in men have shown that it significantly lowers the risk of fracture. Teriparatide should not be combined with bisphosphonates. There are no clear recommendations on the order of treatment with teriparatide and bisphosphonates. The high costs ofteriparatide have slowed the trajectory from registration to reimbursem...
A patient with an untreated carcinoma of the prostate was admitted with dehydration, stupor and a... more A patient with an untreated carcinoma of the prostate was admitted with dehydration, stupor and a surprisingly deep hypocalcaemia. The severe hypocalcaemia was largely attributed to extensive osteoblastic activity due to widespread skeletal metastases although contributing factors to the severity of the hypocalcaemia were a relative vitamin D deficiency, hypomagnesaemia and renal impairment, preventing the mounting of an adequate homeostatic response. There was significant clinical and biochemical improvement after antitumour treatment using androgen deprivation, and supplementation with calcium and vitamin D.
Bailliere's clinical endocrinology and metabolism, 1988
Over the past decade important advances in our understanding of the pathophysiology and treatment... more Over the past decade important advances in our understanding of the pathophysiology and treatment of renal osteodystrophy have been made. In particular, the role of calcitriol deficiency in the genesis of hyperparathyroidism in early renal failure is now better understood. So too are the effects of aluminium on bone, and whereas the more florid aluminium related disease is now unusual the more subtle effects of aluminium are now being appreciated. There is still a major problem in the long-term treatment of hyperparathyroid bone disease. The reasons why parathyroid gland proliferation continues to occur on dialysis therapy require a better understanding of cellular events regulating hormone production and parathyroid cell replication. The case for early intervention with vitamin D is now strong but whether such an approach materially influences the long-term outcome is not yet established. Changes in the approach to treatment and in the modalities used for renal replacement therapy ...
1. The effects of three intravenous diphosphonates (etidronate, clodronate and aminohexane diphos... more 1. The effects of three intravenous diphosphonates (etidronate, clodronate and aminohexane diphosphonate) on phosphate homoeostasis were studied in 30 patients with Paget's disease of bone and in three patients with hypoparathyroidism. 2. In Paget's disease, all three diphosphonates induced significant increases in serum phosphate and renal tubular reabsorption of phosphate. This effect was most marked and persistent after etidronate, whereas in the clodronate- and aminohexane diphosphonate-treated patients the increases were less, of shorter duration and followed thereafter by significant decreases in serum phosphate and renal tubular reabsorption of phosphate. Unlike etidronate, both clodronate and aminohexane diphosphonate caused a significant reduction in serum and urinary calcium, with appropriate homoeostatic increases in immunoassayable parathyroid hormone. 3. Phosphaturic responses to infused parathyroid hormone were observed in two patients with etidronate-induced h...
Considerable confusion arises in defining osteomalacia in the presence of renal disease. There ar... more Considerable confusion arises in defining osteomalacia in the presence of renal disease. There are no radiographic or biochemical features which satisfactorily identify all patients with osteomalacia. Histological definitions need to distinguish increased amounts of osteoid due to defective mineralisation from that due to increased bone turnover, both of which may coexist in chronic renal failure. The pathogenesis of osteomalacia in renal failure is multifactorial and not always due to defective metabolism of vitamin D. Deficient production of 25-hydroxyvitamin D may occur because of nutritional privation or urinary losses in the nephrotic syndrome, but these are rare causes of osteomalacia in patients on haemodialysis treatment. It is not clear to what extent defective production of calcitriol, characteristic of end-stage chronic renal failure is causally related to osteomalacia, in part due to uncertainties as to whether vitamin D acts directly on bone to promote mineralisation or...
1. We studied the acute effects of intranasal and subcutaneous calcitonin in 40 patients with act... more 1. We studied the acute effects of intranasal and subcutaneous calcitonin in 40 patients with active Paget's disease of bone. Patients received a single dose of either 400 units of calcitonin delivered as a nasal spray, or 1, 10 or 100 units of subcutaneous calcitonin, or placebo. 2. Subcutaneous salmon calcitonin, administered at doses of 1, 10 and 100 units to nine patients with Paget's disease of bone, induced a dose-dependent fall in the serum calcium. This calcium-lowering effect was not seen with a second group of nine patients receiving placebo. 3. The lower doses of calcitonin had significant effects, and these were more pronounced in patients with lower rates of bone turnover. 4. Four hundred units of calcitonin administered as a nasal spray induced effects qualitatively similar to those seen with subcutaneous calcitonin, with an efficacy equivalent to approximately 30 units of subcutaneous calcitonin. 5. We conclude that the bioequivalence of calcitonin given by in...
5053 Background: Survival of men with testicular cancer is long due to successful therapeutic int... more 5053 Background: Survival of men with testicular cancer is long due to successful therapeutic intervention, which usually includes orchidectomy. Therefore, we studied the prevalence of osteoporosis in a single center cohort of long term survivors of germ cell cancer. Methods: In a cross-sectional study design, we studied 186 male patients with a mean age of 39.6 years (range 18.1–66.8), who were treated between 1977 and 2006 for germ cell cancer. 181 (97.3%) patients underwent an unilateral, 3 (1.6%) a bilateral orchidectomy and in 2 (1.1%) patients no orchidectomy but retroperitoneal or mediastinal tumor biopsy was performed to confirm the diagnosis. 141 (75.8%) patients received cisplatin-based combination chemotherapy for metastases or primary extra-gonadal tumor at a mean age of 29.4 years (range 14.2- 62.6). Between 2003 and 2006, bone mineral density (BMD) was measured at the lumbar spine and femoral neck by DXA and Z-scores calculated. Vertebral deformities were evaluated by ...
Nederlands tijdschrift voor geneeskunde, Jan 21, 2006
The management of osteoporosis has been dominated by the use of antiresorptive agents, such as bi... more The management of osteoporosis has been dominated by the use of antiresorptive agents, such as bisphosphonates and raloxifene, which have been shown to effectively reduce the risk of osteoporotic fractures. Teriparatide, a recombinant human parathyroid hormone, has recently become available. It has an altogether different action. Teriparatide is an anabolic agent that primarily stimulates bone formation. This leads to an increase in bone volume and the bone structure and microarchitecture is restored by an increase in trabecular thickness and an increase in the number of connections between trabeculae. Clinically relevant studies on teriparatide in postmenopausal women and in men have shown that it significantly lowers the risk of fracture. Teriparatide should not be combined with bisphosphonates. There are no clear recommendations on the order of treatment with teriparatide and bisphosphonates. The high costs ofteriparatide have slowed the trajectory from registration to reimbursem...
A patient with an untreated carcinoma of the prostate was admitted with dehydration, stupor and a... more A patient with an untreated carcinoma of the prostate was admitted with dehydration, stupor and a surprisingly deep hypocalcaemia. The severe hypocalcaemia was largely attributed to extensive osteoblastic activity due to widespread skeletal metastases although contributing factors to the severity of the hypocalcaemia were a relative vitamin D deficiency, hypomagnesaemia and renal impairment, preventing the mounting of an adequate homeostatic response. There was significant clinical and biochemical improvement after antitumour treatment using androgen deprivation, and supplementation with calcium and vitamin D.
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