[Prevalence of histological types of bone disease in a hemodialysis center limiting the oral intake of aluminum hydroxide]. / Prévalence des variétés histologiques d'ostéopathie dans un centre d'hémodialyse limitant la prise orale de l'hydroxyde d'aluminium.

UNLABELLED: To assess the prevalence of histologic bone disease in our center where Al(OH)3 intake is restricted, we reviewed 42 bone biopsies performed between 1975 and 1985 in patients dialyzed more than 29 months. Bone biopsies were performed systematically (2/3 of the cases) or because of a mild hypercalcemia (1/3 of the cases). Seventeen of these patients had been dialyzed before 1978 with softened water moderately contaminated by aluminum. Fifteen had always been dialyzed with reverse osmosis treated water and 10 had been exclusively treated by hemofiltration. The prevalence of osteitis fibrosa was 76%, that of osteomalacia null and that of adynamic bone disease 24% (but only 9.5% with positive Aluminon staining). When the 17 patients dialyzed with aluminum contaminated water before 1978 were excluded, only one patient among 25 had an aluminum adynamic bone disease (4%). This low prevalence can probably be explained by the restricted intake of Al(OH)3 thanks to the systematic administration of Ca CO3 and in a few cases of Mg (OH). The adynamic bone disease group has lower serum concentration of PTH and shorter duration on dialysis whereas the serum levels of calcium, phosphorus, magnesium and aluminum and daily dose of Ca CO3, Mg (OH)2 and Al(OH)3 do not differ. The frequency of the positivity of aluminum staining is not statistically different in the 2 groups. In 4 cases, adynamic bone disease without aluminum or iron intoxications is found, associated with a relative hypoparathyroidism. It is not explained by previous parathyroidectomy, diabetes or steroid therapy. CONCLUSIONS: 1) Restriction of aluminum intake and dialysis with reverse osmosis treated water lead to a low prevalence of aluminum bone disease. 2) A new bone disease in uremia is described: the idiopathic adynamic bone disease associated with a relative hypoparathyroidism.

Prevention of osteitis fibrosa, aluminium bone disease and soft-tissue calcification in dialysis patients: a long-term comparison of moderate doses of oral calcium +/- Mg(OH)2 vs Al(OH)3 +/- 1 alpha OH vitamin D3.

Since 1980, moderately large doses of oral calcium (80 +/- 35 mmol/day as CaCO3 +/- calcium polystyrene sulphonate), in association if necessary with Mg(OH)2 (2.5 +/- 1 g/day), with a reduction in the dialysate Mg concentrations from 0.75 to 0.375 mmol/24 h, have replaced A1(OH)3 as phosphate binders in our centre. A1(OH)3 was previously given to our haemodialysis patients in association with small doses of Ca CO3 (less than or equal to 3 g/day) and if necessary with 1 alpha OH vitamin D3. To compare the long-term efficacy of this new approach with the former one in the prevention of renal osteodystrophy and soft-tissue calcification, 32 current patients were selected on the basis of at least 24 months of treatment in our centre and availability of a yearly bone survey (profile of lumbar spine and anteroposterior view of the pelvis, shoulders and hands). A group of 30 patients treated before 1980 were then selected on the same criteria and matched for age, sex, and duration on dialysis. Linear calcifications of the anterior and posterior walls of the aorta in front of L2, L3, L4 and on the lateral walls of the iliac and femoral arteries were measured and the para-articular calcifications and subperiosteal resorptions of the hands evaluated. The initial extent and the subsequent increase of the ocular and para-articular calcification were comparable in the two groups. Plasma alkaline phosphatase was stable in the normal range in both groups, as was plasma concentration of calcium. Plasma phosphate was slightly elevated (1.7 mmol/l) but stable and comparable in the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Disappearance of aluminic bone disease in a long term asymptomatic dialysis population restricting A1(OH)3 intake: emergence of an idiopathic adynamic bone disease not related to aluminum.

In dialysis centers using reverse osmosis-treated water but not restricting A1(OH)3 administration, a high prevalence of histological aluminum bone disease has been reported. To assess whether this is also the case in our center where A1(OH)3 intake has always been restricted and even completely given up after 1980 thanks to high doses of CaCO3, we reviewed 42 bone biopsies performed between 1975 and 1985 in patients dialyzed for a mean duration of 56 months. Seventeen of these patients had been dialyzed before 1978 with softened water moderately contamined by aluminum, 15 had always been dialyzed with reverse osmosis-treated water and 10 had been exclusively treated by hemofiltration. The prevalence of aluminum bone disease in the whole population was 9.5% (4 patients) and consisted only of adynamic bone disease, osteomalacia being totally absent. When the patients dialyzed with aluminum-contaminated water were excluded as well as 1 diabetic patient who had taken A1(OH)3 for 1.5 years the prevalence of aluminum bone disease was null in this population. When the whole population is considered the prevalence of the other types of bone disease was 76% for osteitis fibrosa and 14.5% for a non-aluminic adynamic bone disease (6 cases). These latter cases differed from the osteitis fibrosa group only by a relative hypoparathyroidism not explained by higher plasma concentrations and higher oral cumulative doses of calcium, magnesium and aluminum or by lower plasma concentrations of phosphate and bicarbonate. None had previous parathyroidectomy, one had an unsuccessful transplantation and one was diabetic. Iron overload was excluded by negative Perls staining.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of vascular calcinosis risk factors in patients on chronic hemodialysis: lack of influence of calcium carbonate.

UNLABELLED: Linear calcifications of the abdominal aorta and of the iliac and femoral arteries were measured yearly for 3 years on X rays of 24 patients on chronic hemodialysis taking variable amounts of calcium carbonate and Al(OH)3 but no pharmacological doses of vitamin D or 1 alpha-hydroxylated vitamin D derivatives. The speed of their extension appeared exponential and covariant with the male sex, age only for men and, independently of these two factors, with diastolic blood pressure and blood triglycerides. Plasma concentrations of calcium, phosphate and glucose were covariant with the extension of calcinosis only at a borderline level. The doses of calcium carbonate and the levels of plasma alkaline phosphatase were not at all covariant. CONCLUSIONS: (1) The effect of high doses of calcium carbonate is possibly harmful only when supraphysiological levels of plasma calcium are induced, whereas plasma phosphate is not adequately decreased. The doses of calcium carbonate per se have no deleterious effect (2). Since alkaline phosphatase is not covariant with the extension of calcinosis, the degree of hyperparathyroidism per se does not seem to play a causative role in vascular calcinosis (3). The main risk factors of vascular calcinosis are: age, the male sex, diastolic blood pressure and blood triglycerides.

Magnesium hydroxide as a complementary aluminium-free phosphate binder to moderate doses of oral calcium in uraemic patients on chronic haemodialysis: lack of deleterious effect on bone mineralisation.

To control hyperphosphataemia without hyperaluminaemia, A1(OH)3, which was given in addition to high doses of oral calcium, was replaced by Mg(OH)2 for 6 months in 20 haemodialysed patients and for 20 months in 12. The treatment during the control period was 110 +/- 91 mmol/day of oral calcium element given as CaCO3 and/or Calcium Sorbisterit and 1.05 +/- 1.47 g/day of A1(OH)3. Haemodialysis treatment was 4 h, thrice weekly. To prevent hypermagnesaemia, dialysate magnesium was decreased from 0.75 mmol/l to 0.375 mmol/l. After a control period of 3 months, Mg(OH)2 was given at a mean dose of 2.6 +/- 2 g/day and oral calcium supplements were decreased to 76 mmol/day. Two subsequent bone histomorphometry studies were performed at 8 month intervals in four patients and at 20 month intervals in seven patients. The results show a good control of plasma calcium (mean +/- SD: 2.43 +/- 0.1 mumol/l); phosphate (1.76 +/- 0.4 to 1.66 +/- 0.3 mmol/l); aluminum (1.3 +/- 0.1 mumol/l to 0.6 +/- 0.1 mumol/l); alkaline phosphatase (135 +/- 65 to 125 +/- 40 IU); and PTH fragments (PTH C terminal decreased from 260 +/- 214 to 185 +/- 182 pg/ml, PTH medium from 4185 +/- 5113 to 2270 +/- 4880 pg/ml). Plasma magnesium increased from 0.96 +/- 0.2 to 1.54 +/- 0.2 mmol/l. Bone histomorphometry shows no change in mineralisation, and a borderline decrease of resorption parameters. The main side-effects are (1) diarrhoea, which was well controlled by transient treatment with karaya gum, and (2) an increased need for potassium binders.(ABSTRACT TRUNCATED AT 250 WORDS)

1 alpha(OH) vitamin D3 increases plasma aluminum in hemodialized patients taking AI(OH)3.

1 alpha(OH) vitamin D3 at the dose of 6 micrograms per week was given for 4 weeks to 16 stable patients on chronic hemodialysis with a low dialysate aluminum while taking a constant dose of Al(OH)3. A significant increase of their plasma aluminum was observed from 1.2 +/- .25 mumol/l before 1 alpha(OH)D3 to 1.7 +/- .35 during the second fortnight of 1 alpha(OH)D3 administration and this increase surprisingly was maintained at 1.71 +/- .3 up to 6 weeks after 1 alpha(OH)D3 discontinuation. Increases in plasma calcium and decreases in plasma PTH were observed during 1 alpha(OH)D3 administration and these changes were correlated to the changes in plasma aluminum. It is concluded that the increase in plasma aluminum observed with 1 alpha(OH)D3 and after its discontinuation is either due to body aluminum burden redistribution or to increased aluminum intestinal absorption whatever the mechanism is, this effect should lead to close monitoring of plasma aluminum in uremic patients taking 1 alpha OH vitamin D3.