Search PubMed⌕ Search

Biomedical subjects

C L Benhamou

Publications and source records attributed to C L Benhamou.

At least 19 recordsLinked to original sources
PubMed1995

Calciotropic hormones in elderly people with and without hip fracture.

The effects of age on calciotropic hormones are not completely understood. The presence of secondary hyperparathyroidism has previously been demonstrated, particularly in patients with hip fracture. The role of a disturbance of vitamin D metabolism, especially a defect in 1 alpha-hydroxylation, is debated. The aim of this study was to compare serum parathyroid hormone (PTH), osteocalcin and vitamin D metabolites (25(OH)D and 1,25(OH)2D) in osteoporotic elderly patients with hip fracture (HF) and in elderly controls. We studied 57 HF patients aged 83.9 +/- 5.9 years (mean +/- SD) and 68 controls aged 82.5 +/- 5 years recruited during two periods: 1 January and 30 April 1988 and 1989. Patients with chronic renal failure (serum creatinine above 150 mumol/l), cancer, or other metabolic bone disease were excluded. Thirty healthy young adults were studied in 1989 only for measurement of 1,25(OH)2D. (1,25(OH)2D was measured by different laboratories in 1988 and 1989 for technical reasons.) We also measured serum PTH, osteocalcin, total calcium and ionized calcium. 1,25(OH)2D levels were not statistically different between HF patients and controls for the two years, nor between HF patients and young healthy adults in 1989. 25(OH)D was decreased in HF patients (p < 0.003), as was ionized calcium. Serum PTH levels were higher in HF patients than in controls (p < 0.01). A positive correlation has been found between PTH and age in HF patients (r = 0.29; p < 0.03) and in the whole group of HF patients and controls. There was a significant decrease in osteocalcin in HF patients versus elderly controls (p < 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Lipid microcrystals and other rare crystals in the joints].

Although not strictly of crystalline nature, various formations can be observed in joint fluids and be responsible for "microcrystalline" arthritis. They can consist of lipidic structures (cholesterol crystals, fatty lobules, liposomes) or calcium crystalline structures such as calcium oxalate crystals detected in fluids of dialyzed chronic renal failure patients, reflecting primary or secondary oxalosis. Other phosphate calcium crystals have been identified, associated to apatite or pyrophosphate crystals, but their pathogenic role is uncertain. Charcot-Leyden crystals reflect eosinophilic arthritis. A phylogenic role may be played by corticoid suspension crystal or prosthetic debris. Lastly, some crystals can be artefacts, resulting from sampling conditions and storage of joint fluids.

Calcinosis↗
PubMed1994

Fractal organization of trabecular bone images on calcaneus radiographs.

Bone density is not the unique factor conditioning bone strength. Trabecular bone microarchitecture also plays an important role. We have developed a fractal evaluation of trabecular bone microarchitecture on calcaneus radiographs. Fractal models may provide a single numeric evaluation (the fractal dimension) of such complex structures. Our evaluation results from an analysis of images with a varying range of gray levels, without binarization of the image. It is based on the fractional brownian motion model, or more precisely on the analysis of its increment, the fractional gaussian noise (FGN). The use of this model may be considered validated if two conditions are fulfilled: the gaussian repartition and the self-similarity of our data. The gaussian repartition of intermediate lines of these images was tested on a sample of 32,800 lines from 82 images. Following a chi-square goodness-of-fit test, it was checked in 86% of these lines for alpha = 0.01. The self-similarity was tested on 20 images by two estimators, the variance method of Pentland and the spectrum method of Fourier. Self-similarity is defined by lined-up points in a log-log plot of the FGN spectrum or of the variance as a function of the lag. We found two self-similarity areas between scales of analysis ranging from 105 to 420 microns, then above 900 microns, where linear regression produced high mean correlation coefficients (r > or = 0.97). Following this validation, we studied the reproducibility of this new technique. Intra- and interobserver reproducibility, influence of transferring the region of interest, and long-term reproducibility were assessed and given CV of 0.61 +/- 0.15, 0.68 +/- 0.47, 0.53 +/- 0.16, and 2.07 +/- 0.84%, respectively. These data have allowed us to validate the use of this fractal model by checking the fractal organization of our radiographic images analyzed by the model. The good reproducibility of successive x-rays in the same subject allows us to undertake population studies and to envisage longitudinal series.

Calcaneus↗
PubMed1993

[Influence of aging on vitamin D metabolism].

Aging is associated both with calcium deficiency, due to low dietary intake and decreased intestinal absorption, and with vitamin D deficiency, secondary to depletion of body stores resulting from inadequate exposure to sunlight. Hepatic hydroxylation of vitamin D remains normal in elderly individuals. Recent data suggest that renal hydroxylation of vitamin D, previously believed to decrease with advancing age, also remains virtually normal even when creatinine clearance declines, as is very often the case in elderly patients. The combined deficiency in calcium and vitamin D stimulates the secretion of parathyroid hormone which tends to normalize serum calcium levels and causes the bone disorders of senile osteoporosis.

Aged↗
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

Hyperparathyroidism in proximal femur fractures biological and histomorphometric study in 21 patients over 75 years old.

Proximal femur fractures in elderly people are more and more frequent. Falls and senile bone disorders are the risk factors of this fracture. In order to understand the mechanisms of these bone disorders, we studied 21 consecutive patients with this fracture using bone histomorphometry. Measurements of serum intact parathormone (PTH), 25-(OH)-vitamin D, 1,25-(OH) 2-vitamin D and osteocalcin have been performed in these 21 patients, included in a larger series. We excluded patients with renal failure (serum creatinine greater than 140 mumols/l), cancer, or previous metabolic bone disease. There were 19 female and 2 male patients, ranging from 75 to 96 years, (mean 84.9). We found a low frequency of cortical (2/21) and trabecular (3/21) osteoporosis. There was no case of clearcut osteomalacia. Following histomorphometric bone study, two patients showed a typical pattern of hyperparathyroidism, and in a third one, this condition seemed very likely. In these three patients who were among the oldest, and who had high levels of serum PTH, chronic renal failure and primary hyperparathyroidism could be excluded. High bone remodeling was frequent in our patients, as reflected by the enhancement of eroded surfaces (13 cases) and of osteoid thickness (7 cases). Intact PTH level was elevated in our series compared to normal values in adults (in accordance to the PTH elevation in the case control study in a larger series). These findings suggest a major role of a secondary hyperparathyroidism in senile bone disorders favoring proximal femur fractures. This hyperparathyroidism is probably secondary to mild calcium and vitamin D deficiency. It may lead to architectural bone changes favoring this fracture.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

Large-scale open trials with etodolac (Lodine) in France: an assessment of safety.

Two large-scale open-label studies were performed in France to confirm the efficacy and safety of etodolac (Lodine), a new non-steroidal anti-inflammatory drug (NSAID). Study I, a 6-week study performed by 974 rheumatologists, involved 4947 patients who had rheumatoid arthritis (RA), ankylosing spondylitis (AS), or osteoarthritis (OA). Both efficacy and safety were assessed. Study II, a postmarketing safety study performed by approximately 9000 general practitioners, involved 51,355 patients who had rheumatic conditions requiring therapy with NSAIDs. The daily dose of etodolac ranged from 200 to 600 mg/day in these studies, depending on the protocol and patient response. By the end of study I (visit 3), spontaneous pain improved by 33% for patients with RA, by 42% for patients with AS, and by 50% for OA patients. A total of 1276 adverse reactions (AR) were reported during the study, and fewer than half of these were related to study treatment. Only 6 severe reactions were reported; three of these were considered unrelated to study treatment, including 2 deaths. In study II, 10.1% of patients reported 6236 ARs and 9.0% of patients dropped out because of AR. Twenty-one of the ARs reported in study II were judged severe, and all of these patients recovered completely. The overall opinion of safety was assessed as very good or good by 89% of patients. In both studies (greater than 55,000 patients), 11% of patients reported an AR, and severe reactions were rare. These results confirmed the very acceptable risk/benefit ratio of etodolac and rank this drug high for efficacy and safety among the NSAIDs recently introduced in France.

Adolescent↗
PubMed1989

Thoracic and lower cervical spine involvement in a case of rheumatoid arthritis.

The authors report a case of spine involvement in a severe case of rheumatoid arthritis treated with corticosteroids. First, the patient developed acute back pain, related to costovertebral joints arthritis at levels T9-T10. Then, neck pain and cord involvement yielded to diagnosis of cervical interapophyseal joints arthritis; there was a C5-C6 subluxation which necessitated surgical treatment. The conjunction of these two rheumatoid localizations is an uncommon feature. Study by the CT scan is valuable when rheumatoid arthritis of the spine is suspected. Lower cervical spine subluxation, even severe, may be well tolerated. Surgery is necessary when there is medullary involvement.

Arthritis, Rheumatoid↗
PubMed1988

Costo-vertebral arthropathy. Diagnostic and therapeutic value of arthrography.

The authors report five cases of costo-vertebral (CV) joint arthropathies, without osteo-arthritis. The patients had referred pain, with misleading irradiations to the loin or to the abdomen, so that the diagnosis was difficult. The authors have performed in these five cases an arthrography of T11 and T12 CV joints. In every case, the arthrography triggered pain at one of these levels. The arthrography was followed by intra-articular injection of corticosteroid derivative in the symptomatic joint. In these cases, this procedure was a valuable diagnostic and therapeutic method. CV joint arthropathies are frequent, but often lead to incorrect diagnosis. These preliminary results encourage further use of this procedure in CV arthropathies.

Adult↗
PubMed1988

[Geographic distribution of multiple myeloma in the Loiret region. 10-year retrospective epidemiological survey].

Suspecting the presence of a myeloma focus in a forest area of the Loiret department, we have undertaken a retrospective epidemiological survey on this disease. Three surveys were conducted, between 1972 and 1982: the first one among general practitioners; the second one was carried out from immuno-electrophoreses performed at the University Hospital in Orleans; the third survey was carried out from reports on the medical causes of deaths. The mean number of myelomas in the Loiret (0.029 p. cent) is comparable to the national mean (0.025 p. cent), with a sex ratio of 47.09 p. cent of men, also quite similar to the national sex ratio (46.7 p. cent). The different districts were classified according to the percentages observed in "neutral areas" (mean plus or minus a typical variation), "cold areas" (between one and two typical variations below the mean) and "hot areas" (between one and two typical variations above the mean). These results do not permit to ascertain the existence of a geographical focus of myelomas in Loiret but require a more in-depth study of "hot areas".

Epidemiologic Methods↗
PubMed1988

Synovial metastasis of an adenocarcinoma presenting as a shoulder monoarthritis.

A 96-year-old woman presented with monoarthritis of the shoulder from a metastasis affecting both the synovium and the humeral head. Evidence of the metastatic process was based on cytologic study of the synovial fluid (SF), synovial membrane and adjacent bone. A primary cancer site was not discovered. The carcinoembryonic antigen level of SF was greatly enhanced. A similar elevation was not detected in other arthropathies (20 control cases).

Adenocarcinoma↗
PubMed1987

[Arthropathies of the limbs in dialyzed renal failure patients].

During the last few years, articular symptoms have been reported in chronic renal failure patients on maintenance haemodialysis. A prospective study of arthropathies of the limbs was conducted in 73 such patients: 20 had experienced periarthritis, 32 had tendinous calcifications (3 or more in 16 cases), 29 had destructive arthropathies (especially of the hands) and 10 had calcium pyrophosphate dihydrate deposition. The periarthritis attacks were associated with the presence of tendinous calcifications. The destructive arthropathies could be due to calcium apatite microcrystal deposition, but the study provided no direct evidence of this mechanism. However, the pattern of erosive lesions, their location and their possible association with tendinous calcifications in the same joint were suggestive of calcium apatite deposition. Calcium pyrophosphate deposition, which affected the oldest patients, did not seem to be due to chronic renal failure treated with dialysis. The most important arthropathies were found in patients who had been haemodialysed for a long time, although the correlation was not statistically significant. The dialysis pattern did not seem to influence the articular disorders. There were more cases of calcification and periarthritis among patients whose phosphocalcium product (in mg) exceeded 6000, but the difference with other patients was not statistically significant. Periarthritis and arthropathies are truly disabling for these patients.

Calcinosis↗