Metabolic Bone Disease (metabolic + bone_disease)

Distribution by Scientific Domains

Selected Abstracts

Small Intestinal Bacterial Overgrowth: A Possible Risk Factor for Metabolic Bone Disease

Article first published online: 16 SEP 200
Small intestinal bacterial overgrowth (SIBO) is one of the causes of malabsorption syndromes. The prevalence of metabolic bone disease in patients with SIBO is unknown, but a recent prospective case-control study indicated significant contribution of SIBO to the development of metabolic bone disease. We review this and other reports in the literature and discuss the possible mechanisms causing metabolic bone disease in patients with SIBO. [source]

Book review: The Bioarchaeology of Metabolic Bone Disease

Matthew S. Taylor
No abstract is available for this article. [source]

Survey of gastroenterologists' awareness and implementation of AGA guidelines on osteoporosis in inflammatory bowel disease patients: Are the guidelines being used and what are the barriers to their use?,

Julianne H. Wagnon MSN
Abstract Background: The American Gastroenterology Association (AGA) published guidelines to assist clinicians in the evaluation and management of osteoporosis in inflammatory bowel disease (IBD) patients. Two studies suggest that when clinicians utilized the guidelines, the majority of their IBD patients were appropriately screened and treated for metabolic bone disease. The aim was to study whether physicians who say they use the AGA Guidelines are, in fact, following the recommendations, and to assess the barriers preventing the use of the guidelines in the management of osteoporosis in their IBD patients. Methods: In all, 1000 physicians were selected from the AGA membership list and mailed a survey inquiring into awareness and implementation of the guidelines on osteoporosis in IBD patients. The barriers to implementation of the guidelines were also assessed. The sum of 21 self-reported clinical practices (absence = 0, presence = 1) was used to evaluate adherence to the guidelines. A value of 0 implied no adherence while a score of 21 meant complete adherence. Results: Of 304 responders, 27 fellows, 8 retirees, and 11 incomplete responses were not included in the analysis; thus, 258 respondents were the subject of this analysis. Slightly less than half of the responders used the guidelines in decision-making (126, 49%) or in the management (110, 42%) of their IBD patients. Using the scoring system described above, clinicians self-reporting use of the guidelines had a significantly higher clinical practice score than those who did not use the guidelines (Wilcoxon rank sum test; P < 0.0001). Only 18% (12 of 68) of clinicians whose practice was comprised of ,25% IBD patients used the guidelines compared to 60% (113/187) physicians who cared for more IBD patients (chi-square test; P < 0.0001). Physicians who saw more IBD patients (>25%) were also more likely (97/187 = 52%) to assess and treat osteoporosis in their IBD patients. Conversely, only 16% (11/68) of physicians who saw ,25% IBD patients treated osteoporosis (chi-square test; P < 0.0001). The main reason physicians (n = 115) gave for not utilizing the guidelines was because they felt that IBD should be the focus of the visit (48, 42%); 34 (30%) reported that osteoporosis should be managed by another physician. Other barriers cited were lack of time (13, 11%), cost (10, 9%), and lack of knowledge (10, 9%). Conclusions: Most of the responding physicians do not utilize the AGA Guidelines on metabolic bone disease in IBD patients. The physicians who self-reported utilizing the guidelines were actually adhering to the recommendations. Further education regarding the impact of metabolic bone disease in IBD patients and the importance of the guidelines is needed, particularly as it addresses the barriers set forth above. (Inflamm Bowel Dis 2009) [source]

Atrial fibrillation and bisphosphonate therapy

Michael Pazianas
Abstract Bisphosphonates are the most commonly used treatment for osteoporosis and have proven efficacy in the reduction of vertebral and nonvertebral fractures. Recently, concerns have been raised about a possible association between bisphosphonate therapy and atrial fibrillation (AF) following the report of a significant increase in risk of serious AF in women treated with zoledronic acid in the HORIZON study. Subsequent studies have produced conflicting results but have not excluded the possibility of such an association. Currently there is no direct evidence that bisphosphonates exert either acute or chronic effects on cardiac electrophysiology. Nevertheless, altered intracellular electrolyte homeostasis and proinflammatory, profibrotic, and antiangiogenic effects provide potential mechanisms by which atrial conduction could be affected in patients treated with bisphosphonates. In studies in which an increase in risk of AF has been identified, there is no evidence that this translates into increased mortality or increased risk of stroke, and the risk-benefit balance of bisphosphonate therapy in patients with osteoporosis and other forms of metabolic bone disease remains strongly positive. 2010 American Society for Bone and Mineral Research [source]

In Silico Modeling and Simulation of Bone Biology: A Proposal

Nadine A Defranoux
Abstract Contemporary, computer-based mathematical modeling techniques make it possible to represent complex biological mechanisms in a manner that permits hypothesis testing in silico. This perspective shows how such approaches might be applied to bone remodeling and therapeutic research. Currently, the dominant conceptual model applied in bone research involves the dynamic balance between the continual build-up and breakdown of bone matrix by two cell types, the osteoblasts and osteoclasts, acting together as a coordinated, remodeling unit. This conceptualization has served extraordinarily well as a focal point for understanding how mutations, chemical mediators, and mechanical force, as well as external influences (e.g., drugs, diet) affect bone structure and function. However, the need remains to better understand and predict the consequences of manipulating any single factor, or combination of factors, within the context of this complex system's multiple interacting pathways. Mathematical models are a natural extension of conceptual models, providing dynamic, quantitative descriptions of the relationships among interacting components. This formalization creates the ability to simulate the natural behavior of a system, as well as its modulation by therapeutic or dietetic interventions. A number of mathematical models have been developed to study complex bone functions, but most include only a limited set of biological components needed to address a few specific questions. However, it is possible to develop larger, multiscale models that capture the dynamic interactions of many biological components and relate them to important physiological or pathological outcomes that allow broader study. Examples of such models include Entelos' PhysioLab platforms. These models simulate the dynamic, quantitative interactions among a biological system's biochemicals, cells, tissues, and organs and how they give rise to key physiologic and pathophysiologic outcomes. We propose that a similar predictive, dynamical, multiscale mathematical model of bone remodeling and metabolism would provide a better understanding of the mechanisms governing these phenomena as well as serve as an in silico platform for testing pharmaceutical and clinical interventions on metabolic bone disease. [source]

Cytokines, Osteoprotegerin, and RANKL In Vitro and Histomorphometric Indices of Bone Turnover in Patients With Different Bone Diseases,

Heide Siggelkow
Abstract Cytokines are supposed to play an essential role in the regulation of the bone metabolic unit. However, information on cytokine production of primary human osteoblasts from patients with metabolic bone disease is scarce, and few attempts have been made to correlate such data to histomorphometric parameters of individual patients. We investigated 11 patients with metabolic bone disease referred to our outpatient department for bone biopsy and analyzed interleukin (IL)-1, IL-6, and TNF-, protein release and gene expression in primary osteoblast cultures. Compared with four controls, five patients showed normal cytokine protein release, whereas six patients showed much higher levels of interleukin-6 (26-fold) and TNF-, (84-fold). All three cytokines were strongly correlated concerning gene expression and/or protein levels (r = 0.72,0.96). Histomorphometric analysis of the bone samples showed that eroded surface (ES/BS) as a parameter of bone resorption was significantly associated with TNF-,. In addition, RANKL gene expression was positively associated with ES/BS and osteoclast surface (Oc.S/BS). Finally, the formation parameters osteoid volume and osteoid surface were negatively associated with TNF-,. In conclusion, in an in vitro-ex vivo model of bone cells obtained from a group of 11 patients with different forms of metabolic bone disease, cytokine release in conditioned medium was significantly associated with bone resorption and bone formation, as quantified by histomorphometry. TNF-, seemed to be the more important cytokine; its effect on bone resorption could be mediated by RANKL. [source]

Small Intestinal Bacterial Overgrowth: A Possible Risk Factor for Metabolic Bone Disease

Article first published online: 16 SEP 200
Small intestinal bacterial overgrowth (SIBO) is one of the causes of malabsorption syndromes. The prevalence of metabolic bone disease in patients with SIBO is unknown, but a recent prospective case-control study indicated significant contribution of SIBO to the development of metabolic bone disease. We review this and other reports in the literature and discuss the possible mechanisms causing metabolic bone disease in patients with SIBO. [source]

Bone mineral density in hyperthyroidism

Helen Karga
Summary objective, To investigate whether previous hyperthyroidism is a cause of permanent secondary osteoporosis. design and patients, In this cross-sectional study, 164 women with untreated or previously treated overt and symptomatic hyperthyroidism were examined 0,31 years after the initial episode of hyperthyroidism and its treatment, and were compared with a control group of 79 age-matched women without previous history of hyperthyroidism. Subjects with current or previous metabolic bone disease, any antiresorptive treatment for osteoporosis or treatments and habits known to affect bone metabolism were excluded. measurements, The age of the first manifestation of the disease, the age at the measurement of bone mineral density (BMD) at the spine and femoral neck and the interval between diagnosis and treatment of hyperthyroidism and BMD measurement were recorded and the Z-scores and T-scores of BMD were analysed. results, Untreated hyperthyroidism and hyperthyroidism up to 3 years after its diagnosis and treatment were associated with decreased BMD. Three or more years after the first episode of the disease the mean Z-score at both skeletal sites was near zero and not different from the controls. The age at which hyperthyroidism was manifested for the first time had no effect on the final outcome. Women affected at a young age (13,30 years) had a more pronounced loss of BMD when examined untreated or early (< 3 years) after diagnosis, but a BMD significantly above zero if examined later (> 3 years). Older women (aged 51,70 years) showed a similar pattern, although the differences were not significant. Middle-aged subjects (31,50 years) had the smallest loss of BMD during the first 3 years. Analysis of T-scores of former hyperthyroid women aged , 51 years showed no significantly different relative risk (RR) for osteoporosis in comparison with the controls. However, the study was not powered enough to give meaningful RR results. conclusions, Overt symptomatic hyperthyroidism is associated with decreased BMD during the first 3 years after diagnosis and treatment of the disease. After this interval, former hyperthyroid women have a Z-score near zero and not different from women without a history of the disease, apparently because of recovery of the bone density lost early during the course of the disease. Symptomatic hyperthyroidism does not seem to be a cause of long-lasting osteoporosis, and the age of the patient during the first episode is irrelevant. [source]

Role of plasma and urinary calcium and phosphorus measurements in early detection of phosphorus deficiency in very low birthweight infants

M Catache
Aim: To analyse the role of serum and urinary calcium and phosphorus levels in early detection of mineral deficiency in very low birthweight (VLBW) infants born appropriate (AGA) and small for gestational age (SGA). Methods: 64 VLBW infants were included in a cohort study and divided into two groups: AGA (n= 30) and SGA infants (n= 34). Then, they were divided according to the presence of radiological signs of metabolic bone disease (MBD): with MBD (n= 21) and without MBD (n= 34). Blood samples and 6 h urine collections were obtained for calcium, phosphorus, alkaline phosphatase activity and creatinine determinations between 3 and 5 wk of life. Results: There were no biochemical differences between AGA and SGA. Higher values of urinary calcium (MBD = 31.9 20.2, without MBD = 19.8 15.4; p= 0.017), calciuria (MBD = 2.3 0.3, without MBD =1.4 0.8; p= 0.037) and alkaline phosphatase activity (MBD = 369 114, without MBD = 310 93; p= 0.04) were found in infants who developed MBD. Both groups showed high tubular phosphorus reabsorption indicating mineral deficiency. Conclusion: Serum calcium and phosphorus levels are not good markers in early detection of mineral deficiency. However, the monitoring of calcium urinary levels may be helpful in early detection of mineral deficiency. [source]