Biomedical subjects

C Edouard

Publications and source records attributed to C Edouard.

At least 19 recordsLinked to original sources

PubMed1991

[Bone involvement in primary oxalosis. Study of 20 cases].

The authors report 20 cases of primary oxalosis with bone involvement, late revealed in adults in 19 cases. They have studied the clinical, radiological and histological manifestations of this bone oxalosis. 19 cases had an end stage chronic renal failure, either treated by maintenance hemodialysis, or by renal (or liver-renal) graft. 17 patients complained of bone pain after starting hemodialysis; 3 had vertebral crush fractures, and 1 multiple spontaneous fractures. Diffuse bone sclerosis (with a homogeneous pattern on axial skeleton and a patchy appearance on the peripherical skeleton), bone translucency, subperiosteal phalangeal resorption were the main radiological symptoms. Oxalate crystals surrounded by a giant cells granuloma were always observed on bone biopsy (16 cases). Bone resorption was observed in 9 cases, hyperparathyroidism in 14 cases and osteomalacia in 7 cases. Hyperparathyroidism does'nt explain all the clinical and radiological manifestations (especially bone resorption). Bone resorption as other radiological and clinical manifestations can be found without hyperparathyroidism and can increase despite parathyroidectomy; so, bone resorption seems to be partly due to the granulomatous reaction around oxalate crystals rather than hyperparathyroidism.

Adolescent↗

PubMed1991

[A case of severe rarefaction osteopathy associated with tabes dorsalis].

The authors report the case of a 63 years old man who presented 13 years after a diagnosis of a tabes dorsalis, stress fractures of the lower limbs and Charcot's joints (knees). 7 years later, he had multiple stress fractures of the sacrum and pelvis and of the ribs following a minor trauma. Laboratory investigations revealed a major osteoporosis probably related to the neurochirurgical complications of the tabes dorsalis.

Fractures, Stress↗

PubMed1991

Iliac trabecular bone formation predicts radial trabecular bone density changes in type 1 osteoporosis.

In 28 patients with idiopathic or postmenopausal type 1 (spinal crush fracture) osteoporosis, resorption indices and dynamic measurements of trabecular bone formation based on in vivo tetracycline labeling in 7.5 mm transiliac biopsies have been compared with trends in radial cortical and trabecular bone density measured with computed tomography. Positive correlations were observed between trabecular bone density trends in the radius and indices of bone formation in the ilium. These were improved when one of the two resorption indices was included with a formation index in bivariate regressions. Marked interindividual variations in radial bone density trends were also seen in cortical bone. These correlated poorly with trends in trabecular bone. Weak negative relationships between cortical bone trends and indices relating to bone formation and resorption were observed, but a positive association was seen with single-labeled surfaces on iliac trabeculae. If, as has been suggested, there are periodic variations in bone formation, the results suggest that axial and peripheral trabecular bone density trends are synchronized in osteoporosis, perhaps in response to systemic factors, such as circulating hormones.

Aged↗

PubMed1991

hPTH 1-34 treatment of osteoporosis with added hormone replacement therapy: biochemical, kinetic and histological responses.

Twelve patients with vertebral fracture osteoporosis were recruited into a trial of treatment with hPTH 1-34 by daily injection for 1 year combined (from the 5th month) with an anti-resorptive agent (oestrogen, n = 9; nandrolone, n = 3). Treatment outcomes were monitored by biochemical and radiotracer measurements together with histomorphometry of transiliac biopsies before and at the end of treatment following double in vivo pre-labelling with demethylchlortetracycline. Indices of whole body bone formation, obtained from the analysis of 85Sr data, showed substantial increases (P less than 0.005) for all three indices measured) while biochemical (hydroxyproline) and kinetic measurements of bone resorption showed modest and equivocal changes only. As a result calcium balance improved. Gastrointestinal calcium absorption showed a tendency to improve, while urine calcium decreased; but these changes were statistically not significant except for radiocalcium absorption in the oestrogen treated subgroup. Histomorphometry revealed substantial increases in cancellous bone volume as reported previously with hPTH 1-34 given alone. However, iliac (as distinct from whole body) indices related to bone formation and resorption appeared to have returned towards pre-treatment values by the time of the second biopsy under the influence of the anti-resorptive agent given with the hPTH 1-34. It is confirmed that hPTH 1-34 therapy can increase iliac cancellous bone mass (as well as spinal cancellous bone mass as reported earlier) without a long-term increment in whole body bone resorption, providing the hPTH is combined with an anti-resorptive agent.

Aged↗

PubMed1991

The relationship between serum vitamin D concentrations and in vivo tetracycline labeling of osteoid in crush fracture osteoporosis.

Twenty of 22 consecutive British patients with crush fracture osteoporosis had transiliac bone biopsies following double in vivo tetracycline labeling synchronized with the collection of serum for the measurement of vitamin D metabolites. A significant but direct (rather than inverse) relationship was found between 25-hydroxyvitamin D (calcidiol) levels and the fraction of cancellous surfaces covered with osteoid not taking either tetracycline label (r = 0.53, P less than 0.02). There was no correlation with 1,25-dihydroxyvitamin D levels. No patient had frankly thickened osteoid seams although 3 had reduced but measurable calcidiol levels. These results make it unlikely that the majority of patients with osteoporosis who have osteoid of normal thickness but reduced uptake of tetracycline have a mineralization defect secondary to vitamin D deficiency. The pathophysiological significance of unlabeled osteoid in osteoporosis requires further investigation.

Aged↗

PubMed1990

Comparison between radial bone mineral density measured by single photon absorptiometry and histomorphometric bone mass parameters measured on iliac crest biopsies.

Bone mineral density (BMD) measured by single photon absorptiometry (SPA) with a Moolsgard 1100 device on the distal and proximal part of the radius was compared with histomorphometric parameters measured on iliac crest biopsies in 37 patients suffering from various bone disorders. In the whole population, a good correlation was observed between the cancellous bone volume (Cn-BV/TV) measured on iliac crest biopsies and BMD from both the proximal part of the radius (r = 0.76, p less than 0.001) and the distal part of the radius (r = 0.73, p less than 0.001). Significant, although weaker correlations, were also found between the cortical width and the BMD from the distal part (r = 0.37, p less than 0.001) and the proximal part (r = 0.44, p less than 0.001) of the radius. In the 14 untreated osteoporotic patients, only a significant Spearman correlation was observed between the iliac Cn-BV/TV and the proximal radial BMD (r' = 0.69, p less than 0.05). It is thus not clear, whether radial proximal BMD correctly indicates cortical bone density in osteoporotic patients or not. The large internal variability of each of the two investigated methods and the small group of osteoporotic patients might explain the lack of correlation between the two methods in this group.

Absorptiometry, Photon↗

PubMed1988

Skeletal blood flow, iliac histomorphometry, and strontium kinetics in osteoporosis: a relationship between blood flow and corrected apposition rate.

In 20 untreated patients with idiopathic or postmenopausal osteoporosis, kinetic studies of skeletal blood flow (using 18F) and bone turnover (using 85Sr) were combined with dynamic histomorphometry performed on transiliac biopsies taken within 6 weeks of each other. In 8 patients the combined studies were repeated after treatment. A further 5 patients were studied only while receiving treatment. As expected, skeletal blood flow measured by 18F correlated with an index of 85Sr uptake into the exchangeable pools of bone. Additionally and independently, skeletal blood flow correlated with an index of the work rate of the osteoblasts in each multicellular unit of bone (the corrected apposition rate of Parfitt). These correlations were statistically significant in both the untreated patients (P less than 0.05) and the whole group (P less than 0.001). Further indices related to bone turnover at the level of the skeleton as a whole were significantly associated with skeletal blood flow only in the combined group.

Aged↗

PubMed1987

Intravenous disodium etidronate therapy in Paget's disease of bone and hypercalcemia of malignancy. Effects on biochemical parameters and bone histomorphometry.

Nineteen patients with Paget's disease and four patients with hypercalcemia of malignancy underwent hypocalcemic therapy with etidronate disodium (etidronate) administered intravenously. The dosage for patients with Paget's disease was 4.3 mg/kg/day, infused on each of seven consecutive days. Nine of the 19 patients also received oral etidronate 5 mg/kg/day for three months after administration of intravenous therapy. Etidronate administered orally sustained the decreases in urinary hydroxyproline produced by the infusions, whereas levels returned to pretreatment values in most patients receiving only the intravenously administered drug. Serum alkaline phosphatase levels were not reduced in the 10 patients receiving only intravenously administered etidronate, but they declined by approximately 50 percent in the nine patients who received the additional orally administered etidronate. Transiliac-crest bone biopsy specimens obtained three months after intravenous therapy revealed a regular lamellar structure, compared with the characteristic woven pattern of pagetic bone. In all four patients with hypercalcemia of malignancy, normocalcemia was achieved by the 10th day of treatment using a dosage of 4.3 mg/kg/day. Oral etidronate therapy was beneficial in maintaining normocalcemia.

Bone and Bones↗

PubMed1987

The assessment of bone formation and bone resorption in osteoporosis: a comparison between tetracycline-based iliac histomorphometry and whole body 85Sr kinetics.

Bone formation and resorption have been measured in patients with idiopathic osteoporosis by histomorphometry of 7.5-mm trephine biopsies and in the whole body by 85Sr radiotracer methodology and calcium balances. The studies were synchronized and most were preceded by double in vivo tetracycline labeling. Correlations between histological and kinetic bone formation indices were better when better when based on the extent of double tetracycline labels than on measurements of osteoid by visible light microscopy. Correction of the kinetic data for long-term exchange, using 5 months' serial whole body counting of retained 85Sr, improved the fit of the kinetic to the histological data. A statistical analysis of the measurement uncertainties showed that the residual scatter in the best correlations (between exchange-corrected bone formation rates and double-labeled osteoid surface indices) could be attributed to measurement imprecision alone. The exchange-corrected resorption rate correlated fairly well with iliac trabecular resorption surfaces, and using a volume referent rather than a surface referent for the histological index improved the statistical fit when patients with therapeutically accelerated bone turnover were included. A much better correlation was obtained by including osteoid volume acting as an independent predictor of bone resorption in a bivariate regression with a resorption surface index. The residual errors could then be accounted for by known measurement uncertainties. Whereas osteoid taking a double label closely predicted the kinetic rate of bone formation, further analysis suggested that osteoid that took no label or a single label was more closely related to bone resorption, presumably as a secondary result of the coupling of bone formation to bone resorption. The idea that continued bone loss in some patients is associated with defective osteoblastic bone formation is supported by the low rates found in some patients by both techniques. Heuristically these studies validate both in vivo tetracycline labeling for dynamic histomorphometry and corrections for long-term exchange in kinetic studies of bone formation, providing a quantitative framework for the design and analysis of future studies of bone remodeling in the osteoporoses.

Adult↗

PubMed1987

Beneficial effects of aminohexane diphosphonate in patients with Paget's disease of bone resistant to sodium etidronate.

Clinical and biochemical resistance to sodium etidronate therapy is not rare in patients with severe Paget's disease of bone, especially after several courses of treatment. Sixteen patients with Paget's disease of bone and well-documented resistance to sodium etidronate were treated with a new diphosphonate, aminohexane diphosphonate, given orally for three months at a daily dose of 400 mg. These patients comprised a selected population of patients with very active disease, as shown by a mean 20-fold increase of serum alkaline phosphatase levels before aminohexane diphosphonate therapy. Aminohexane diphosphonate induced a striking reduction of serum alkaline phosphatase and urinary hydroxyproline levels sustained for up to 18 months after withdrawal of treatment. Two patients had a relapse 14 to 16 months after treatment, and received a second course of aminohexane diphosphonate with the same efficacy. This was accompanied by marked clinical improvement, a reduction of the radioisotope uptake by pagetic bones, and radiologic healing of osteolytic lesions in some cases. Iliac crest biopsy specimens taken after tetracycline double-labeling showed no impairment of bone mineralization. No clinical or biochemical adverse effects have been observed.

Aged↗

PubMed1987

Primary bone oxalosis: the roles of oxalate deposits and renal osteodystrophy.

Primary oxalosis is a rare congenital disorder. The excessive oxalate biosynthesis induces deposits in many organs, particularly in kidney and bone. The late onset of primary oxalosis is reported in a 50-year-old man. His chronic renal failure was treated by maintenance hemodialysis for 3 years. He then developed a diffuse bone disease with osteosclerosis and roentgenographic features of hyperparathyroidism. A parathyroidectomy was performed, with debatable improvement of bone lesions. Laboratory results and histologic and histomorphometric studies before and after parathyroidectomy suggest a double histopathogenetic mechanism for this bone disease: renal osteodystrophy and massive bone oxalate deposits. Such deposits may induce both a heterogeneous osteosclerosis with dense metaphyseal bands and histologic bone lesions similar to those of hyperparathyroidism. The crystalline deposits induce in the bone tissue a granulomatous macrophagic reaction. These macrophages are unable to phagocytize the crystals and may be involved in active bone resorption. Bone lesions of oxalosis occur in patients with chronic renal failure, and hyperparathyroidism has a worsening role.

Bone and Bones↗

PubMed1987

Periodic courses of human 1-34 parathyroid peptide alternating with calcitriol paradoxically reduce bone remodelling in spinal osteoporosis.

In an attempt to achieve an anabolic response in both axial and peripheral bone, we treated twelve patients with osteoporosis using human 1-34 parathyroid peptide given discontinuously. The peptide was given as seven daily subcutaneous injections followed by 21 days' treatment with 0.25 mg calcitriol orally. This regime was repeated cyclically for at least sixteen cycles, of which the first four were at a lower dose of hPTH 1-34 than used subsequently. The results of treatment were monitored by kinetic, densitometric, histomorphometric and biochemical studies performed before and during treatment. Two patients developed hPTH 1-34 binding in their plasma during treatment: this was presumed to be due to the development of antibodies. The remainder, instead of increasing their indices of bone turnover as judged by iliac bone histomorphometry, were found to have consistent reductions in trabecular resorption surfaces. The other indices of bone formation and resorption measured showed no change or comparable reductions. The small increases seen in total body calcium were consistent with 'in-filling' of deleted basic multicellular units (BMUs). Because there is no evidence that calcitriol alone causes comparable reductions in activation of bone remodelling in osteoporosis, interruption of treatment with hPTH 1-34 after 7 days may have led to a failure of the activation mechanism to proceed to the resorption stage, with a consequent overall reduction in remodelling activity. This type of treatment regime, with its calcitonin-like effect, might be effective in reducing net bone loss due to imbalance between bone formation and resorption at the BMU level, particularly in patients with increased numbers of BMUs ('high turnover' osteoporosis).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1987

Effects of clodronate on immobilization bone loss.

Clodronate can be used in animals to prevent the effects of immobilization on bone. For this reason we have studied the effects of this agent on immobilisation bone loss in man. We administered clodronate by mouth to 14 paraplegic patients (400 mg/d, n = 7; 1600 mg/day, n = 7), and compared its effect with a placebo (n = 7). Treatment was given for 100 days, 5-29 days after spinal cord injury. Our results suggest that clodronate, given early after immobilization, prevents the acute bone loss observed in immobilization as judged by its effects on serum and urine calcium and hydroxyproline, bone mineral content, trabecular bone volume, and the number of osteoclasts present in bone. No mineralization defect or other side-effects were observed during or after treatment. In addition, a total of 70 patients, with comparable degrees of immobilization, were studied with a variety of antiosteoclastic drugs comprising controls (n = 16), etidronate (n = 20), salmon calcitonin (n = 20) and clodronate 400 mg/d (n = 7) or 1600 mg/d (n = 7). Clodronate, at the dose of 1600 mg/d appeared the most effective drug on bone resorption, together with calcitonin. Unlike calcitonin, clodronate can be administered orally. The mineralisation defects observed during prolonged treatment with etidronate at high doses were not observed with clodronate. We conclude that clodronate 1600 mg/d is a promising agent for the treatment of bone loss and the resorptive hypercalcaemia and hypercalciuria noted in immobilisation.

Animals↗

PubMed1986

Fluoride treatment in corticosteroid induced osteoporosis.

Severe osteoporosis with multiple vertebral fractures occurred in two girls receiving prolonged high dose corticosteroids for relapsing dermatomyositis. Sodium fluoride, supplemented with calcium and vitamin D, helped control secondary osteoporosis in one case and should be considered as part of the curative treatment of corticoid induced osteoporosis.

Child↗

PubMed1986

Serum bone gamma carboxyglutamic acid-containing protein in primary hyperparathyroidism and in malignant hypercalcemia. Comparison with bone histomorphometry.

Serum bone gamma-carboxyglutamic acid-containing (Gla) protein (sBGP), a sensitive and specific marker of bone turnover, was measured in 25 patients with primary hyperparathyroidism and in 24 patients with bone metastases with or without hypercalcemia. Despite similar levels of hypercalcemia, sBGP was increased in primary hyperparathyroidism (14.2 +/- 9.6 ng/ml, P less than 0.001), was decreased in malignant hypercalcemia (3.1 +/- 2.8 ng/ml, P less than 0.001), and was normal in patients with bone metastases without hypercalcemia (6.6 +/- 2.7 ng/ml). In primary hyperparathyroidism, sBGP was correlated with serum immuno-reactive parathyroid hormone (r = 0.90), calcium (r = 0.73), and with the adenoma weight (r = 0.79). After parathyroidectomy, sBGP slowly returned to normal values within 2-6 mo, suggesting that sBGP reflects increased bone turnover rather than a direct effect of parathyroid hormone on BGP synthesis at the cell level. An iliac crest biopsy was performed in 11 patients with primary hyperparathyroidism and in 9 cancer patients in a noninvaded area. sBGP was significantly correlated with all parameters reflecting bone formation but not with bone resorption. Patients with bone metastases were analyzed according to the presence or the absence of hypercalcemia. In contrast to normocalcemic patients who had normal sBGP, hypercalcemic patients had decreased sBGP (P less than 0.001) and a lower bone formation at the cellular level (P less than 0.05). Thus, biochemical and histological data suggest that an unknown humoral factor might be responsible for this uncoupling between increased resorption and decreased formation. This uncoupling, rather than local release of calcium by the metastatic process, might be responsible for hypercalcemia in patients with bone metastases.

Adenocarcinoma↗

PubMed1985

Heterogeneity of fracture syndromes in postmenopausal women.

Studies were performed on 32 women with vertebral crush fractures (mean age, 65.1 yr) and 27 patients with recent hip fractures (mean age, 83.6 yr). Histomorphometric analysis of undecalcified transiliac crest biopsies revealed significant differences between the two fracture groups. Trabecular bone volume (TBV) was significantly lower in vertebral fracture than in hip fracture patients (12.0 +/- 4.4% (+/- SD) vs. 14.8 +/- 3.6%; P = 0.014), while thickness of cortices was significantly lower for hip fracture than for vertebral fracture patients (436 +/- 231 vs. 823 +/- 465 microns; P less than 0.001). The TBV and radial bone mass (measured by absorptiometry on the shaft) for the vertebral fracture group were significantly lower than age-expected values. For the patients with hip fractures, the TBV was significantly above the expected value, and radial bone mass was not significantly different from the expected value. Other quantitative histological measurements did not generally differ between the two fracture groups and were compatible with normal or increased bone remodeling. The serum PTH in the hip fracture group was significantly increased above that expected in normal women of similar age. These data demonstrate the anatomical heterogeneity of osteoporotic fracture syndromes. Patients with vertebral fractures have an early deficit of trabecular bone for their age, while those with hip fractures have a deficit of both cortical and trabecular bone compared to women of age 50 yr, but the deficit is not excessive compared to others of similar age without fractures.

Aged↗

PubMed1984

[Myelomatous bone. Histomorphometric study and therapeutic effects].

In order to evaluate quantitatively the bony changes in multiple myeloma, 118 transiliac bone biopsies in non decalcified bone were made in patients with multiple myeloma and studied histologically. Areas of osteoclastic resorption were increased when compared to normal controls and the number of osteoclasts/mm2 in spongy bone was significantly more elevated in zones massively invaded by plasmocytes than in non-invaded zones. The binding of tetracycline to osteoid was increased, indicating active bone formation. However, the reduced thickness of the osteoid and the rate of calcification measured by double labeling with tetracycline showed reduced osteoblastic activity at the cellular level. The volume of trabecular bone was not significantly reduced when compared to controls but plasmocyte infiltration was quite variable in distribution. In invaded zones, there was no noteworthy difference in the different parameters analyzed between patients receiving chemotherapy and those untreated. This shows that if chemotherapy can reduce the tumoral mass of plasmocytes, it does not change the increased osteoclastic activity of these areas. These histological findings justify the usage of antiosteoclastic agents such as the diphosphonates.

Adult↗

PubMed1984

Impaired osteoblast function in osteoporosis: comparison between calcium balance and dynamic histomorphometry.

Osteoblast function was investigated in 27 patients with idiopathic osteoporosis. Transiliac bone biopsy specimens were taken after double labelling with tetracycline, and metabolic calcium balance was studied almost simultaneously. Many of the patients showed poor double labelling of their otherwise unremarkable trabecular osteoid, suggesting impaired formation of bone at many of these surfaces. This phenomenon was not accompanied by increased width of osteoid seams (as seen in osteomalacia), indicating that formation of the matrix and its mineralisation were in equilibrium. For the first time, highly significant positive correlations (p less than 0.01) were found between indices of bone formation, determined by labelling with tetracycline, and calcium balance. Thus some patients with osteoporosis who are rapidly losing bone have low rates of formation of trabecular bone both by individual osteoblasts and in relation to available bone surfaces. As histological indices of bone resorption also independently correlated strongly and inversely (p less than 0.01) with calcium balance the rate of initiation of new basic multicellular units by osteoclastic resorption of trabecular surfaces (or the depth of resorption at these surfaces) also appears to be an important determinant of mineral balance. The mechanisms that regulate the effective life span of mature osteoblasts require further investigation, particularly as some promising treatments that can increase trabecular bone volume in osteoporosis, such as parathyroid peptide hPTH (1-34) and sodium fluoride, must work through a reversal of osteoblastic depression.

Aged↗