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E Shane

Publications and source records attributed to E Shane.

At least 37 records · Page 2Linked to original sources
PubMed1998

Prevention of bone loss after heart transplantation with antiresorptive therapy: a pilot study.

BACKGROUND: Heart transplantation, with its attendant glucocorticoid and cyclosporine therapy, has deleterious effects on the skeleton. We have previously reported rapid bone loss and high fracture rates (36% of patients) during the first year after heart transplantation. The bone loss was accompanied by declines in serum 1,25-dihydroxyvitamin D and osteocalcin levels and increased urinary excretion of markers of bone resorption (hydroxyproline, pyridinoline, and deoxypyridinoline). We therefore investigated whether bone loss could be prevented by bisphosphonates, agents that inhibit bone resorption. METHODS: Serial measurements of bone mineral density (BMD) and biochemical indexes of mineral metabolism were compared in 18 group A patients who received a single intravenous infusion of pamidronate (60 mg) within 2 weeks of heart transplantation, followed by 4 cycles of oral etidronate (400 mg daily for 14 days every 3 months) and oral calcitriol 0.25 microg daily, to those of 52 patients who previously underwent transplantation (group B) who did not receive antiresorptive therapy. Both groups received elemental calcium 1000 mg and vitamin D 400 IU daily. RESULTS: At 12 months after transplantation, there was virtually no lumbar spine bone loss in group A patients, whereas lumbar spine BMD had declined significantly in group B patients (0.2% +/- 0.9% vs 6.8% +/- 1.0%, respectively; P < .0001). Similarly, femoral neck BMD fell by 10.6% +/- 1.1% in group B patients and by only 2.7% +/- 1.4% in group A patients (P < .0001). Three incident vertebral fractures occurred in two group A patients, whereas 17 group B patients sustained 30 incident vertebral fractures, one hip fracture and three episodes of rib fractures (P < .02; test of proportions). With respect to markers of bone resorption, urinary deoxypyridinoline fell by 51% +/- 9% in group A patients and increased by 65% +/- 22% in group B patients by 3 months after transplantation (P < .0001). CONCLUSION: In summary, heart transplant recipients treated with bisphosphonates and replacement doses of calcitriol sustained less bone loss and fewer fractures than those treated with calcium and vitamin D. We conclude that bisphosphonate therapy, in conjunction with calcitriol, shows promise for prevention of transplantation-related osteoporosis.

Absorptiometry, Photon↗
PubMed1997

Bone mass, vitamin D deficiency, and hyperparathyroidism in congestive heart failure.

PURPOSE: In contrast to renal and hepatic failure, congestive heart failure (CHF) has not been associated with a defined metabolic bone disorder. However, low bone mass has been reported in patients with CHF who receive a cardiac transplant. Both the pathophysiology and therapy of CHF may influence bone and mineral homeostasis and evidence that calciotropic hormones may affect cardiovascular function is accumulating. Therefore, we evaluated patients with severe CHF to determine the prevalence of osteoporosis and to characterize relationships between mineral homeostasis, bone turnover, bone mass, and severity of CHF. PATIENTS AND METHODS: One hundred one patients (79 men and 22 women, aged 25 to 70 years) with severe CHF (New York Heart Association functional class III or IV) referred for consideration for cardiac transplantation were evaluated with measurements of serum 25-hydroxyvitamin D (25-OHD), 1,25 dihydroxyvitamin D [1,25(OH)2D], intact parathyroid hormone (PTH), markers of bone turnover (serum osteocalcin, urinary hydroxyproline, and pyridinium crosslinks); bone mineral density (BMD) by dual energy x-ray absorptiometry was measured in 91 patients. Left ventricular ejection fraction (LVEF) and resting cardiac output (CO) were determined in 88 and maximal treadmill exercise testing and peak oxygen consumption were performed in 45 patients. RESULTS: Osteoporosis (T score < or = -2.5) was present in 7% at the lumbar spine, 6% at the total hip, and 19% at the femoral neck. Osteopenia (T scores between -1.0 and -2.5) was present in 43% at the lumbar spine, 47% at the total hip, and 42% at the femoral neck. Women were more severely affected (P = 0.007). Frankly low serum 25-OHD (< or = 9 pg/mL) and 1,25(OH)2D (< or = 15 pg/mL) levels were found in 17% and 26% of the patients, respectively, and elevated serum PTH (> or = 65 pg/mL) in 30%. Both low serum 1,25(OH)2D and increased serum PTH were associated with prerenal azotemia. Low serum vitamin D metabolites were associated with biochemical evidence of increased bone turnover, but BMD did not differ by vitamin D or PTH status. Patients with more severe CHF had significantly lower vitamin D metabolites and higher bone turnover, whereas elevated PTH was associated with better LVEF (21 +/- 1 versus 18 +/- 1%; P = 0.05) and correlated positively with resting CO (R = 0.220; P = 0.04). CONCLUSIONS: Osteopenia or osteoporosis were observed in approximately half of these patients with severe CHF. Abnormal calciotropic hormone concentrations, also common, were associated with evidence of increased bone resorption but were not related to BMD in this cross-sectional study. Abnormal concentrations of calciotropic hormones were related to the severity of cardiovascular compromise. Because both low BMD and low serum concentrations of 25-OHD in patients with CHF are associated with higher rates of bone loss and fracture after cardiac transplantation, patients should be evaluated for and receive appropriate therapy for these disorders.

Absorptiometry, Photon↗
PubMed1997

Bone loss and turnover after cardiac transplantation.

Cardiac transplantation is associated with increased prevalence and incidence of fracture, and rapid bone loss has been reported during the first posttransplant year. To define further the pattern and etiology of bone loss after cardiac transplantation, we enrolled 70 patients (52 men and 18 women) in a prospective 3-yr study. Bone densitometry (BMD) and biochemical indexes of mineral metabolism were performed before and at defined times after transplantation. Despite supplementation with elemental calcium (1000 mg/day) and vitamin D (400 IU/day), the mean rate of bone loss during the first year was 7.3 +/- 0.9% (+/- SEM) at the lumbar spine and 10.5 +/- 1.1% at the femoral neck. The rate of bone loss slowed (P < 0.001 compared to year 1) at both sites (0.9 +/- 0.9% and 0.1 +/- 1.0%, respectively) during the second year. During the third year, lumbar spine BMD increased at a rate of 2.4 +/- 0.8%/yr (P < 0.02 compared to year 2), but femoral neck BMD did not change. At the radius, the rate of decline in BMD was negligible during the first year (0.9 +/- 0.5%), but was significant during the second (2.1 +/- 0.6%; P < 0.01) and third (2.9 +/- 0.8%; P < 0.03) years. Evaluation of the pattern of bone loss during the first year demonstrated that mean lumbar spine BMD decreased rapidly during the first 6 months, after which there was no further decline. In contrast, femoral neck BMD continued to fall at an annualized rate of 8.2 +/- 1.3% during the second half of the year. The pattern and rates of bone loss were similar in men and women. Biochemistries revealed decreases in serum testosterone and osteocalcin and increases in all bone resorption markers 1 and 3 months after transplantation, with a return to baseline by 6 months. Higher rates of bone loss were associated with greater exposure to prednisone, lower serum concentrations of vitamin D metabolites, greater suppression of osteocalcin, higher levels of bone resorption markers, and, in men, lower serum testosterone concentrations. We conclude that rapid bone loss is primarily confined to the initial year after transplantation. During the first 6 months, bone loss is accompanied by alterations in markers of bone turnover consistent with biochemical uncoupling of bone formation and resorption. Greater exposure to glucocorticoids, lower serum concentrations of vitamin D metabolites and testosterone, and higher bone turnover were associated with more rapid bone loss.

Adult↗
PubMed1997

Insulin-like growth factor-I in men with idiopathic osteoporosis.

The etiology of osteoporosis in most men without a history of alcohol abuse, hypogonadism, or glucocorticoid excess is unknown. Several histomorphometric reports have demonstrated a reduction in indices of bone formation. We tested the hypothesis that the putative reduction in bone formation in men with idiopathic osteoporosis may be related to deficiencies in skeletal mechanisms that are mediated by insulin-like growth factor I (IGF-I). Twenty-four middle-aged men (50.5 +/- 1.9 yr) with severe idiopathic osteoporosis (mean lumbar spine T-score -3.5 +/- 0.16) were studied. The following biochemical indices were all normal: serum calcium, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, testosterone, osteocalcin, carboxyterminal propeptide of type I collagen, bone specific alkaline phosphatase, urinary calcium, and collagen crosslinks. Parathyroid hormone level was in the lower range of normal, 25 +/- 2 pg/mL (nl: 10-65). Mean serum IGF-I level was also in the lower range of normal, 157.9 +/- 7.6 ng/mL (normal age-matched range, 140-260 ng/mL). Eight men had IGF-I levels that were below 140 ng/mL. The mean IGF-IZ score was -0.75, significantly different from the expected mean of zero (P = 0.0002). IGF-I was correlated negatively with age (r = -0.49, P < 0.02). With age held constant, serum IGF-I accounted for 15% of the variance in lumbar bone mineral density (BMD; P < 0.001). The osteocalcin concentration correlated well with bone density at the distal 1/3 radius (r = +0.44; P < 0.002). Histomorphometric analysis of bone biopsy specimens showed significant reductions in cancellous bone volume (31%; P < 0.001), cortical width (28%; P < 0.05), osteoid surface (33%; P < 0.01), and bone formation rate (54%; P < 0.01) when results were compared with age-matched control subjects. Percent eroded surface was normal and was correlated inversely with serum IGF-I levels (r = -0.5; P < 0.04). These results suggest that serum IGF-I levels are reduced in men with idiopathic osteoporosis and that IGF-I correlates with and may contribute to the reduction in lumbar spine bone mass density (BMD). The low IGF-I levels may reflect the reduction in bone formation demonstrated by histomorphometry. Insights into the etiology of idiopathic osteoporosis in men may be revealed by further studies of the IGF-I axis.

Adult↗
PubMed1997

Tumor-induced osteomalacia: clinical and basic studies.

A patient with classic clinical and biochemical features of tumor-induced osteomalacia (hypophosphatemia, phosphaturia, and undetectable serum concentrations of 1,25-dihydroxyvitamin D [1,25(OH)2D]) was studied before and after resection of a benign extraskeletal chondroma from the plantar surface of the foot. Presurgical laboratory evaluation was notable for normal serum concentrations of calcium, intact parathyroid hormone (PTH), parathyroid hormone-related protein (PTHrP), and osteocalcin, increased serum alkaline phosphate activity, and frankly elevated urinary cyclic adenosine monophosphate (cAMP) and pyridinium cross-link excretion. Quantitative histomorphometry showed severe osteomalacia and deep erosions of the cancellous surface by active osteoclasts. After resection, serum 1,25(OH)2D normalized within 24 h, while renal tubular phosphorus reabsorption and serum phosphorus did not normalized until days 2 and 3, respectively; serum Ca declined slightly, and serum intact PTH, osteocalcin, and urinary pyridinium cross-link excretion increased dramatically. Urinary cAMP excretion declined immediately after resection and then began to increase concomitant with the increase in serum intact PTH. A second bone biopsy taken 3 months after resection demonstrated complete resolution of the osteomalacia, increased mineral apposition rate (1.09 mu/day), resorption surface (9.2%), mineralizing surface (71%), and bone formation rate (0.83 mm3/mm2/day), and marked decrease in cancellous bone volume (13.1%) and trabecular connectivity compared with first biopsy. Tumor extracts did not affect phosphate transport in renal epithelial cell lines or 1 alpha-hydroxylase activity in a myelomonocytic cell line. The patient's course suggests that the normal 1,25(OH)2D and phosphorus metabolism is due to a tumor product that may be acting via stimulation of adenylate activity. Increased bone resorption prior to surgical resection suggests that the tumor may also produce an osteoclast activator. The rise in resorption surface and pyridinium cross-link excretion, increase in serum osteocalcin and bone mineralization, normalization of osteoid width, and fall in cancellous bone volume after resection are consistent with healing of osteomalacia by rapid remodeling.

25-Hydroxyvitamin D3 1-alpha-Hydroxylase↗
PubMed1997

Insufficiency fractures of the sacrum: a cause of low back pain after lung transplantation.

Insufficiency fractures of the sacrum were diagnosed during the first year after successful transplantation in four (5.6%) of 71 lung and heart-lung transplant recipients. Each patient had development of low back pain after minor or no trauma; all had osteoporosis. In each instance, plain radiographs failed to demonstrate the fracture, and the diagnosis was established by radionuclide bone scanning that demonstrated the characteristic "butterfly" (bilateral sacral fracture) or "half-butterfly" appearance (unilateral sacral fracture). Sacral insufficiency fractures, a significant cause of low back pain in lung transplant recipients, may be underdiagnosed in this population because routine radiographs do not usually reveal the fracture; bone scanning is the preferred diagnostic modality.

Absorptiometry, Photon↗
PubMed1996

Osteoporosis in lung transplantation candidates with end-stage pulmonary disease.

PURPOSE: Fractures, a common complication of cardiac and liver transplantation, have not been reported in association with lung transplantation. However, many patients with end-stage pulmonary disease have multiple risk factors for osteoporosis, and several studies have suggested that osteoporosis before transplantation may increase the risk of fracture after transplantation. Therefore, we evaluated a group of patients with end-stage pulmonary disease who were awaiting lung transplantation to determine the prevalence of osteoporosis. METHODS: Seventy patients (aged 18-70 years) were evaluated consecutively with bone densitometry by dual-energy x-ray absorptiometry. The patients were predominantly Caucasian (96%). Bone mass was expressed as bone mineral density (BMD; g/cm2), as the number of standard deviations (SD) below peak bone mass (T score), and as bone mineral apparent density (BMAD; g/cm3), a measurement that minimizes the effects of bone size on BMD. Spine radiographs were obtained in a subset of 50 consecutive patients to detect vertebral compression fractures. Vitamin D status was assessed with serum concentrations of 25-hydroxyvitamin D. The patients were sorted into groups by pulmonary diagnosis: chronic obstructive pulmonary disease (COPD; n = 28); cystic fibrosis (n = 11); idiopathic pulmonary fibrosis; and other lung diseases (Other; n = 31). RESULTS: In the group as a whole, osteoporosis (T score below -2.5) was present in 30% of the patients at the lumbar spine and 49% at the femoral neck. Osteopenia (T score between -1 and -2.5) was present in an additional 35% at the lumbar spine and 31% at the femoral neck. The average femoral neck T score of patients with COPD and cystic fibrosis fell into the osteoporotic range (-2.7 +/- 0.3 and -2.6 +/- 0.3, respectively), significantly (P < 0.01) below that of the patients in the Other category (-1.5 +/- 0.3). The average lumbar spine T score fell into the osteopenic range in all three groups. Low BMAD in patients with cystic fibrosis confirmed that their low BMD was not due to their smaller body size. The prevalence rate of vertebral fractures was 29% in patients with COPD and 25% in those with cystic fibrosis. Vitamin D deficiency (25-hydroxyvitamin D levels < or = 10 ng/ml) was present in 36% of patients with cystic fibrosis and 20% with COPD and Other lung diseases. Lumbar spine BMD tended to be lower in cystic fibrosis patients with vitamin D deficiency. Patients with exposure to glucocorticoids (n = 46) had significantly more vertebral fractures (P < 0.05) and duration of exposure correlated negatively with lumbar spine BMD (r = -0.398; P = 0.008). COPD and Other patients not on glucocorticoids had mild lumbar spine osteopenia (0.972 +/- 0.06 g/cm2; T = -1.2 +/- 0.6). Very few of the patients on glucocorticoids were on any regimen to prevent osteoporosis. CONCLUSIONS: Osteoporosis and vitamin D deficiency are extremely common in patients with end-stage pulmonary disease. Only 34% of patients had normal lumbar spine BMD and only 22% had normal BMD at the hip. Patients with cystic fibrosis and glucocorticoid-treated patients with COPD were most severely affected. Therapies to prevent bone loss and treat established osteoporosis are uncommonly utilized in glucocorticoid-treated patients with end-stage pulmonary disease. Candidates for lung transplantation should be evaluated for osteoporosis and vitamin D deficiency at the time of acceptance to the transplant waiting list.

Absorptiometry, Photon↗
PubMed1996

Fracture after cardiac transplantation: a prospective longitudinal study.

Cardiac transplantation is associated with increased prevalence of vertebral fractures, but the natural history of and risk factors for fracture after this life-saving procedure are unclear. We evaluated 47 patients (34 men and 13 postmenopausal women) before transplantation with spinal radiographs, determination of bone density by dual energy x-ray absorptiometry, and measurement of biochemical indexes of mineral metabolism. During the first year after transplantation, incident fractures were documented radiographically. Associations among demographic characteristics, bone density, biochemistries, and fracture risk were evaluated with logistic regression analysis. Despite supplementation with elemental calcium (1000 mg/day) and vitamin D (400 IU/day), 17 patients (7 women and 10 men) sustained a total of 34 fractures. Most fractures involved the spine, and 85% of the patients who experienced fracture did so within 6 months of transplantation. Fifty-four percent of the women and 29% of the men experienced fracture. Femoral neck bone mineral density was significantly lower in women who experienced fracture than in those who did not (0.604 +/- 0.11 vs. 0.760 +/- 0.12 g/cm2; P < 0.04), but did not differ in men according to fracture outcome. The amount of bone loss at the femoral neck by 6 months after transplantation was significantly greater in men with fracture than in men without fracture (12.0 +/- 6.4% vs. 6.8 +/- 5.3%; P < 0.04), but did not differ in women according to fracture outcome. Pretransplant 1,25-dihydroxyvitamin D levels were significantly lower (25 +/- 9 vs. 39 +/- 17 pg/mL; P < 0.007) and intact PTH levels tended to be higher in men who did not experience fracture (37 +/- 15 vs. 69 +/- 46 pg/mL; P < 0.06). Individual pretransplant bone density measurements demonstrated substantial overlap between patients who did and did not experience fracture, and normal bone density did not necessarily protect against fracture after transplantation. We conclude that fractures are a common and early complication of cardiac transplantation. No pretransplant measurement has yet been identified that reliably predicts fracture after transplantation in the individual patient.

Bone Density↗
PubMed1995

Bone structure in postmenopausal hyperparathyroid, osteoporotic, and normal women.

The purpose of this study was to test the hypothesis that patients with mild primary hyperparathyroidism are protected against postmenopausal (PM) loss of cancellous bone architecture. To achieve this, we compared bone structure and turnover in iliac bone biopsies from three groups: 16 women with mild primary hyperparathyroidism (PHPT; 58.2 +/- 2.2 years, 11.5 +/- 1.7 years PM), 17 women with untreated primary osteoporosis (OP; 65.1 +/- 2.0 years, 17.2 +/- 2.3 years PM), and 31 healthy women (N; 59.8 +/- 1.4 years, 13.4 +/- 1.5 years PM). The bone formation rate was significantly higher in PHPT than in either OP or N, and not different between OP and N. Cancellous bone volume, total strut length, and indices of connectivity (node number, node to node strut length, and node to terminus ratio) were significantly lower in OP than in either PHPT or N but were the same or higher in PHPT than in N. Indices of disconnectivity were significantly lower in PHPT than in N, whereas they were the same or higher in OP than N. The data were also analyzed in subgroups matched by years PM with no changes in the results. These findings indicate that osteoporotic patients with normal bone turnover have low bone volume and microarchitectural deterioration, while patients with mild PHPT have normal bone volume and normal or greater trabecular connectivity despite higher bone turnover. These findings suggest that mild PHPT protects against the loss of cancellous bone structure that normally follows menopause.

Bone and Bones↗
PubMed1995

Organ transplantation and osteoporosis.

Organ transplantation offers new life to patients who suffer from incurable disease. The problem of rejection of the transplanted organ has been overcome with the use of potent immunosuppressive drugs. These drugs, although they allow graft tolerance and graft survival, also are associated with complications such as osteoporosis. Although factors such as nutrition, gonadal status, and ambulatory status are important, the use of immunosuppressive drugs appears to be the main factor in the development of osteoporosis. The drugs that are responsible for this bone loss are glucocorticoids and the calcineurin phosphatase inhibitors, cyclosporine and tacrolimus. The incidence of bone disease depends, in part, on which organ is transplanted. Kidney transplant recipients appear to be less susceptible to the development of overt osteoporosis than do heart or liver transplant recipients. The most critical period of bone loss in organ recipients appears to be within the first 6 months, with the most dramatic reduction occurring within the first 3 months following transplantation. Trabecular (cancellous) bone of the spine appears to be most at risk, with vertebral fractures occurring most commonly. Transplant recipients should be evaluated by bone mineral densitometry and measurement of vitamin D metabolites, blood urea nitrogen, creatinine, calcium, and phosphate. Markers of bone turnover may help in assessing the rate of remodeling. Gonadal function should be ascertained by measurement of serum testosterone (males) or estradiol (females) levels. Therapy should be directed toward prevention of bone loss as well as helping to restore what already may have been lost. Administration of calcium and vitamin D and sex hormone replacement, if indicated, should be considered.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcitonin↗
PubMed1995

Longitudinal measurements of bone density and biochemical indices in untreated primary hyperparathyroidism.

A large number of patients with primary hyperparathyroidism today do not undergo parathyroidectomy. In this prospective study, we evaluated the effect of untreated disease on biochemical and bone densitometric indices. In 66 patients, seven annual measurements showed no change in serum calcium, phosphorus, PTH, vitamin D, or alkaline phosphatase; in urinary calcium, hydroxyproline or hydroxypyridinium cross-link excretion; or lumbar spine, femoral neck, and radial bone mineral density. The subset of postmenopausal women also showed no change in biochemical indices or bone density at any of the three sites. Twenty-four patients met guidelines for surgery as established by the NIH Consensus Conference, 1990. They differed from those who did not meet these guidelines only by being younger (50 +/- 3 vs. 62 +/- 2 yr; P = 0.0005) and by having higher urinary calcium excretion [7.7 +/- 0.9 vs. 5.4 +/- 0.3 mmol/L (310 +/- 37 vs. 215 +/- 14 mg/g creatinine); P < 0.01]. No longitudinal changes in biochemical profile or bone mineral density at any site were noted in this subgroup. Conservative management of patients with mild primary hyperparathyroidism does not lead to progression of disease, as reflected by biochemical indices. Bone density is maintained over 6 yr of observation at sites reflecting both cortical (radius) and cancellous (lumbar spine) bone.

Adult↗
PubMed1995

Increased bone mineral density after parathyroidectomy in primary hyperparathyroidism.

Skeletal involvement in primary hyperparathyroidism is characterized by preferential loss of cortical bone, whereas cancellous bone is relatively spared. Little data are available concerning changes in bone density, particularly at sites containing more cancellous bone, after successful parathyroidectomy. Most patients with primary hyperparathyroidism are asymptomatic, but approximately 50% meet one or more criteria for surgery. In a prospective study of 34 patients who met one or more such criteria, bone density rose at all skeletal sites (lumbar spine, femoral neck, and the radius) in the 4 yr after surgery. The lumbar spine, with most cancellous bone, showed a rapid (mean +/- SE, yr 1, 8.2 +/- 2.0%; P < 0.005) and sustained (yr 4, 12.8 +/- 2.8%; P < 0.001) rise. Post-menopausal patients were similar (by yr 4, 12.5 +/- 2.7%; P < 0.005). At the femoral neck, with intermediate cancellous and cortical composition, a similar increase was noted (12.7 +/- 3.8% by yr 4; P < 0.01). The distal radius, containing mostly cortical bone, rose modestly (4.0 +/- 1.5% by yr 3; P < 0.05), except in patients with lowest preoperative bone density, where the increase was marked (12.3 +/- 2.6% by yr 3; P < 0.05). In patients meeting surgical guidelines, parathyroidectomy is associated with improved bone mineral density.

Adult↗
PubMed1994

Hereditary hyperphosphatasia: 20 year follow-up and response to disodium etidronate.

We provide a 20 year follow-up of a family with three siblings affected by hereditary hyperphosphatasia (HH). An iliac crest bone biopsy was performed on one of the siblings following double-tetracycline labeling, with results reported quantitatively in a standard histomorphometric format. Biochemical parameters of disease activity were monitored in the patient before and after treatment with oral etidronate disodium, 20 mg/kg/day taken for 5 weeks. Biochemical evidence of intense disease activity continued 20 years after the initial diagnosis of HH in the sibling studied. His bone biopsy specimen also revealed extremely high bone turnover but low cancellous bone volume and osteoclasts unlike those found in Paget's disease. Treatment with etidronate disodium resulted in a temporary 40% reduction in serum alkaline phosphatase and 24 h urine hydroxyproline excretion, with reduction in serum osteocalcin from two times the upper limit of normal to a subnormal level. We conclude that disease activity in HH can continue unabated for two decades. Our bone biopsy finding of low cancellous bone volume, the consistent lack of pagetic-looking osteoclasts in our and other studies, plus the clinical features of HH (childhood onset and extremely diffuse disease with gross skeletal deformation) serve to distinguish HH from Paget's disease. Bisphosphonates may be of value in treating HH.

Adult↗
PubMed1993

Osteoporosis after cardiac transplantation.

PURPOSE: The purpose of this study was to determine the prevalence of osteopenia and fractures and to describe the biochemical indices of mineral metabolism in patients who have undergone cardiac transplantation. PATIENTS AND METHODS: Forty adult patients who had received a cardiac transplant between 1982 and 1990 and who were receiving immunosuppressive therapy with prednisone and cyclosporine A were studied. Bone densitometric measurements by dual-energy x-ray absorptiometry of the lumbar spine and femoral neck and radiographs of the thoracic and lumbar spine were obtained for all patients. Routine serum and urine biochemical values as well as more specialized biochemical analyses (intact parathyroid hormone, metabolites of vitamin D, and osteocalcin) were obtained. RESULTS: Osteopenia was present in 28% of the patients at the lumbar spine and 20% of the patients at the femoral neck. Vertebral fractures were present in 35% of patients. In contrast to other patients receiving glucocorticoids, serum osteocalcin, a marker of bone formation, was elevated in 60% of patients. CONCLUSIONS: Osteopenia and vertebral fractures are common in patients after cardiac transplantation. The presence of elevated osteocalcin levels suggests that the pathogenesis of the osteoporosis in these patients differs from that of glucocorticoid-induced osteoporosis.

Absorptiometry, Photon↗
PubMed1992

Maintenance of cancellous bone connectivity in primary hyperparathyroidism: trabecular strut analysis.

We previously demonstrated an increase in cancellous bone volume and trabecular number in patients with mild primary hyperparathyroidism (PHPT). To test the hypothesis that this increase is due to preservation of cancellous bone architecture, we conducted a trabecular strut analysis using a new method that measures trabecular connectivity. Iliac crest biopsies from 37 patients with PHPT, 14 men (28-68 years) and 23 women (26-68 years), were examined histomorphometrically and compared to cadaveric samples from 24 age-matched subjects, 17 men and 7 women. Two-dimensional indices of cancellous structure--node number (N.Nd), terminus number (N.Tm), node to node (Nd.Nd), node to terminus (Nd.Tm), and terminus to terminus (Tm.Tm) strut lengths, and total strut length (TSL)--were measured and the ratio of node number to terminus number (N.Nd/N.Tm) calculated. TSL, N.Nd, and Nd.Nd were significantly higher in patients than in controls. TSL and Nd.Nd, but not N.Nd or Nd/Tm, decreased significantly with age in PHPT, indicating that age-related bone loss in PHPT occurs without significant loss of trabecular connectivity. Two-dimensional indices reflecting connectivity or the amount of bone, that is, N.Nd, Nd.Nd, N.Nd/N.Tm, and TSL, correlated positively with cancellous bone volume (BV/TV) and trabecular number (Tb.N) and negatively with trabecular spacing (Tb.Sp) in both PHPT and controls. Trabecular thickness (Tb.Th) correlated positively with Nd.Nd and Tb.N and negatively with Tm.Tm in PHPT but not in controls. The present data show that in PHPT there is not only greater cancellous bone volume and trabecular number but preserved trabecular connectivity as well. The data further support the hypothesis that in PHPT cancellous bone architecture is maintained.

Adult↗
PubMed1991

Characterization and evaluation of asymptomatic primary hyperparathyroidism.

Data are presented on 97 patients with primary hyperparathyroidism who constitute a representative cohort of the disease seen today. The average calcium (11.1 +/- 0.1 mg/dl; normal 8.7-10.7), phosphorus (2.8 +/- 0.1 mg/dl; normal 2.5-4.5), and parathyroid hormone level by immunoradiometric assay (119 +/- 7 pg/ml; normal 10-65) are typical of the modern presentation of primary hyperparathyroidism. Most patients were asymptomatic in that there was evidence for nephrolithiasis in only 18% and for radiologically evident bone disease in only 1% of patients. Nevertheless, when patients were evaluated with bone densitometry and with histomorphometric analysis of the bone biopsy specimen, evidence for the hyperparathyroid process could be shown in the majority of patients. Selective reduction of cortical bone and preservation of cancellous bone were apparent. Among patients with nephrolithiasis, no particular feature distinguished them from patients without nephrolithiasis. All biochemical data were similar between both stone and non-stone formers. The selective reduction in cortical bone was seen to the same extent among those with stones as among those without stones. The average 1,25-dihydroxyvitamin D level was not increased among those with stones. When the population was divided into groups with elevated or normal 1,25-dihydroxyvitamin D levels, the incidence of nephrolithiasis was unchanged. The results indicate that bone involvement can be demonstrated among most patients with asymptomatic primary hyperparathyroidism and that no pathophysiologic mechanisms are yet apparent to account for nephrolithiasis in primary hyperparathyroidism.

Adult↗