Effects of hormonal replacement therapy on bone metabolism in young adults with beta-thalassemia major

Hematological Diseases and Osteoporosis

Secondary osteoporosis is a common clinical problem faced by bone specialists, with a higher frequency in men than in women. One of several causes of secondary osteoporosis is hematological disease. There are numerous hematological diseases that can have a deleterious impact on bone health. In the literature, there is an abundance of evidence of bone involvement in patients affected by multiple myeloma, systemic mastocytosis, thalassemia, and hemophilia; some skeletal disorders are also reported in sickle cell disease. Recently, monoclonal gammopathy of undetermined significance appears to increase fracture risk, predominantly in male subjects. The pathogenetic mechanisms responsible for these bone loss effects have not yet been completely clarified. Many soluble factors, in particular cytokines that regulate bone metabolism, appear to play an important role. An integrated approach to these hematological diseases, with the help of a bone specialist, could reduce the bone fracture rate and improve the quality of life of these patients.

Denosumab in transfusion-dependent thalassemia osteoporosis: a randomized, placebo-controlled, double-blind phase 2b clinical trial

Denosumab (DNM) is a fully human monoclonal antibody against the receptor activator of nuclear factor kappa-B ligand (RANKL) that has been licensed for the treatment of different types of osteoporosis. However, the prospective data for the evaluation of DNM efficacy on transfusion-dependent thalassemia (TDT)-induced osteoporosis are rather limited. Thus, we conducted a randomized, placebo-controlled, double-blind, phase 2b clinical trial to evaluate DNM in TDT osteoporosis. Patients were assigned to receive either 60 mg DNM (n = 32) or placebo (n = 31) subcutaneously on day 0 and 180 during a total of 12 months of follow-up. The percentage increase of L1-L4 bone mineral density was higher in the DNM group than the placebo group (5.92% ± 5.25% vs 2.92% ± 5.56%, respectively; P = .043), whereas the advantage of DNM regarding wrist bone mineral density was much higher compared with placebo (-0.26% ± 5.31% vs -3.92% ± 8.71%, respectively; P = .035). No grade 3 or 4 toxicity was observed. DNM reduced pain scores that remained unaltered in the placebo group. DNM showed a significant reduction of soluble RANKL (sRANKL), sRANKL/osteoprotegerin ratio, C-telopeptide of collagen type I, tartrate-resistant acid phosphatase isoform-5b, and bone-specific alkaline phosphatase between baseline and the 12th month (P < .01 for all comparisons) without changes in dickkopf-1, sclerostin, and osteocalcin. On the contrary, placebo patients showed an increase in sRANKL, osteoprotegerin, dickkopf-1, sclerostin, C-telopeptide of collagen type I, tartrate-resistant acid phosphatase isoform-5b, and bone-specific alkaline phosphatase during the study period (P < .01 for all comparisons). In conclusion, DNM increased lumbar spine and wrist bone mineral density and reduced pain and bone remodeling markers, and thus it is another valuable option for the management of TDT-induced osteoporosis. This trial was registered at www.clinicaltrials.gov as #NCT02559648.

Pathogenesis of Thalassemia Major-associated Osteoporosis: A Review with Insights from Clinical Experience

Due to increasing life expectancy in thalassemia major (TM), osteoporosis is emerging as a significant problem. Its aetiology is multifactorial, culminating in increased bone resorption and impaired remodelling. Hypogonadism and marrow expansion seem to play an important role, but iron overload, deferoxamine toxicity, a defective growth hormone-insulin-like growth factor-1 axis and multiple endocrinopathies may represent additional causes of bone damage. Many of these patients, though under appropriate treatment programs, do not achieve normal peak bone mass. The receptor activator of nuclear factor kappa-ß (RANK)/RANK ligand/osteoprotegerin and the Wnt/β-catenin systems work as major mediators of imbalanced bone turnover and bone loss. Additional genetic factors, such as collagen type 1 alpha 1 and vitamin D receptor gene polymorphisms, may exert some influence on the enhanced fracture risk observed in TM. To date, in spite of adequate hormone replacement, chelating therapy and acceptable haemoglobin levels, subjects with TM display impaired bone density and imbalanced bone turnover, thus the puzzle of the pathogenesis of TM-induced osteoporosis remains far from being solved.

Evaluation of osseous changes in dental panoramic radiography of thalassemia patients using mandibular indexes and fractal size analysis

OBJECTIVE

This study aimed to evaluate the radiomorphometric indexes and fractal dimension (FD) on dental panoramic radiography (DPR) of Thalassemia Major (TM) patients.

METHODS

In 59 TM patients and in 59 healthy control subjects, mandibular cortical index (MCI), mandibular cortical width (MCW), panoramic mandibular index (PMI), and FD of four different regions (FD1-4) were evaluated and compared using DPRs.

RESULTS

The distribution of MCI in TM patients was similar to control subjects (p > 0.05). The mean MCW was significantly lower in TM patients (p = 0.001). There was no significant difference in PMI between TM patients and control subjects. The mean of FD measured in the supracortical area above the angle of mandible (FD2), in the anterior to the mental foramen (FD4) and mean FD of four different regions was significantly lower in TM patients (p = 0.003, p = 0.001, and p = 0.014, respectively).

CONCLUSIONS

The radiomorphometric indices and fractal dimensions evaluated in the panoramic radiograph are capable of identifying thalassemia patients' jaw bone, and the results of DPR scanning can be used to refer these patients to appropriate medical investigation.

The role of biphosphonates in the management of thalassemia-induced osteoporosis: a systematic review and meta-analysis

Thalassemia Major (TM) is a clinical entity with a high prevalence of low bone mass. The aim of the present study was to perform a meta-analysis of all available data on the role of bisphosphonates (BPs) in the therapy of thalassemia major-induced osteoporosis. The PRISMA recommendations for reporting systematic reviews and meta-analyses were used to guide the present study. We searched PubMed and the Cochrane Central Register of Controlled Trials (CENTRAL) through March 31, 2017 for articles related to thalassemia and BPs. To meta-analytically synthesize the primary endpoint, we used the standardized mean difference (SMD) after Hedges's g transformation under the scenario of a random effects model. Heterogeneity across studies was examined using the I² statistic. Nine randomized controlled trials (RCTs) containing original data were included in this review. Three studies were performed in Italy, one in Australia, three in Greece, one in Cyprus, and one in China. The BPs investigated included zoledronate, alendronate, pamidronate, clodronate, and neridronate. Zoledronate and alendronate showed a tendency to perform best as compared to neridronate and the placebo effect with respect to femoral neck, lumbar spine, total hip, and total body in terms of bone mass density (g/cm²). BPs and in particular, zolendronate, were quite effective in the treatment of osteoporosis. These findings suggested that bisphosphonates are still a front-line treatment of osteoporosis in TM. However, to draw more meaningful and significant conclusions for the use and efficacy of BP in TM, larger and more complete RCTs should be conducted.

Intestinal calcium transport and its regulation in thalassemia: interaction between calcium and iron metabolism

Osteoporosis and derangement of calcium homeostasis are common complications of thalassemia. Despite being an important process for bone and calcium metabolism, little is known about intestinal calcium transport in thalassemia. Recent reports of decreases in both intestinal calcium transport and bone mineral density in thalassemic patients and animal models suggested that defective calcium absorption might be a cause of thalassemic bone disorder. Herein, the possible mechanisms associated with intestinal calcium malabsorption in thalassemia are discussed. This includes alterations in the calcium transporters and hormonal controls of the transcellular and paracellular intestinal transport systems in thalassemia. In addition, the effects of iron overload on intestinal calcium absorption, and the reciprocal interaction between iron and calcium transport in thalassemia are elaborated. Understanding the mechanisms underlining calcium malabsorption in thalassemia would lead to development of therapeutic agents and mineral supplements that restore calcium absorption as well as prevent osteoporosis in thalassemic patients.

A contemporary therapeutic approach to bone disease in beta-thalassemia - a review

Homozygous beta-thalassemia represents a serious hemoglobinopathy, in which an amazing prolongation in the survival rate of patients has been achieved over recent decades. A result of this otherwise positive evolution is the fact that bone problems have become a major issue in this group of patients. Through an in-depth review of the related literature, the purpose of this study is to present and comment on the totality of the data that have been published to date pertaining to the prevention and treatment of thalassemia bone-disease, focusing on: the contribution of diet and lifestyle, the treatment of hematologic disease and its complications, the management of hypercalciuria, the role of vitamins and minerals and the implementation of anti-osteoporosis medical regimen. In order to comprehensively gather the above information, we mainly reviewed the international literature through the PubMed database, searching for the preventive and therapeutic data that have been published pertaining to thalassemia bone-disease over the last twenty-nine years. There is no doubt that thalassemia bone-disease is a complication of a multi-factorial etiopathology, which does not follow the rules of classical postmenopausal osteoporosis. Bisphosphonates have been the first line of treatment for many years now, with varied and usually satisfactory results. In addition, over the last few years, more data have arisen for the use of denosumab, teriparatide, and other molecules that are in the clinical trial phase, in beta-thalassemia.

Minerals in thalassaemia major patients: An overview

Thalassaemia major (TM) is a hereditary blood disease characterised by reduced or absent production of beta globin chains. Erythrocyte transfusions are given to raise the haemoglobin level in patients with thalassaemia major. However, transfusions have been related to increased risk of iron overload and tissue damage related to excess iron. Both elevated oxidative stress due to iron overload and increased hemolysis lead to over utilisation of minerals required for antioxidant enzymes activities. Iron chelators have been used to prevent iron overload in thalassaemia major patients, but these chelators have the possibility of removing minerals from the body. Thalassaemia patients are more at risk for mineral deficiency because of increased oxidative stress and iron chelation therapies. Growth and maturational delay, cardiomyopathy, endocrinopathies and osteoporosis are the complications of thalassaemia. Minerals may play a particular role to prevent these complications. In the current review, we provide an overview of minerals including zinc (Zn), copper (Cu), selenium (Se), magnesium (Mg) and calcium (Ca) in thalassaemia major patients. We, also, underline that some complications of thalassaemia can be caused by an increased need for minerals or lack of the minerals.

Bone Health in Patients With Hematopoietic Disorders of Bone Marrow Origin: Systematic Review and Meta- Analysis

Blood cell production and bone homeostasis are physically interlinked systems that exhibit active cross-talk. We examined how bone health is affected in patients with hematopoietic disorders due to abnormal proliferation of bone marrow cells. The electronic databases Medline, Embase, PubMed, BIOSIS Previews, Web of Science, and Cochrane were searched for studies presenting numerical values for trabecular bone volume or bone mineral density in control and patients with hematopoietic disorders. We identified 5 studies for beta-thalassemia, 6 for sickle cell anemia, 2 for polycythemia vera and essential thrombocythemia, 3 for chronic myelogenous leukemia, 6 for myelofibrosis, 5 for multiple myeloma, and 4 studies each for systemic mastocytosis, lymphocytic leukemia, and hemochromatosis. The effect of the disease state on bone density was significant and negative for beta-thalassemia (r = -2.00; 95% confidence interval [CI] -3.41, -0.58; p < 0.005), sickle cell anemia (-0.91; -1.36, -0.47; p < 0.00005), chronic myelogenous leukemia (-0.55; -0.88, -0.22; p < 0005), mastocytosis (-0.99; -1.16, -0.82; p < 0.00001), lymphoblastic leukemia (-0.69; -0.98, -0.40; p < 0.00001), multiple myeloma (-0.67; -0.99, -0.35; p < 0.00005), and hemochromatosis (-1.15; -1.64, -0.66; p < 0.00001). The changes were negative but not significant for polycythemia vera (-0.16; -0.38, 0.05; p = 0.069) and essential thrombocythemia (-0.33; -0.92, 0.26; p = 0.14). In myelofibrosis, disease state was associated with increased bone density (0.74; 0.12, 1.36; p < 0.05). Bone density change significantly and negatively correlated with the level of ferritin and bone marrow cellularity but not with hemoglobin or erythropoietin. Thus, independent of hematopoietic lineage, abnormal proliferation of bone marrow cells appears to be associated with bone loss. Iron metabolism may independently contribute to bone homeostasis. © 2016 American Society for Bone and Mineral Research.

Thalassemia-associated osteoporosis: a systematic review on treatment and brief overview of the disease

Thalassemia-associated osteoporosis constitutes a major complication in patients with thalassemia. This review presents the existing studies on the treatment of thalassemia-associated osteoporosis and discusses the management of this debilitating complication. A brief presentation of the disease characteristics and pathogenetic mechanisms is also provided. The life expectancy of patients with thalassemia has increased markedly in recent years resulting in the aging of the population and the emergence of new comorbidities. The majority of patients with thalassemia have low bone mineral density and experience lifelong fracture rates as high as 71 %. The pathogenesis of thalassemia-associated osteoporosis (TAO) is multifactorial with anemia and iron overload playing crucial role in its development. Data concerning the prevention and treatment of TAO are extremely limited. We performed a literature research in Pubmed and Scopus to identify interventional studies evaluating the effects of various agents on TAO. Seventeen studies were retrieved. We present the results of these studies as well as a brief overview of TAO including presentation, pathogenesis, and management. Most of the studies identified are of poor quality, are not randomized controlled, and include small number of participants. There are no data concerning effects on fracture rates. Bisphosphonates are the most widely studied agents and among them zoledronic acid is the most well studied. Hormone replacement treatment (HRT) shows beneficial but small effects. Denosumab and strontium ranelate have each been evaluated in only a single study, while there are no data about the effects of anabolic agents. Given the increased life expectancy and the increase in fracture rates with age, more data about the management of TAO are warranted. Moreover, due to the need for lifelong management starting at young age, careful treatment plans which may include sequential treatment may often be required. However, currently, there are no relevant data available.

Effects of strontium ranelate on bone mass and bone turnover in women with thalassemia major-related osteoporosis

Subjects affected by thalassemia major (TM) often have reduced bone mass and increased fracture risk. Strontium ranelate (SrR) is an effective treatment for postmenopausal and male osteoporosis. To date, no data exist on the use of SrR in the treatment of TM-related osteoporosis. Our aim was to evaluate the effects of SrR on bone mineral density (BMD), bone turnover markers and inhibitors of Wnt signaling (sclerostin and DKK-1). Twenty-four TM osteoporotic women were randomized to receive daily SrR 2 g or placebo in addition to calcium carbonate (1,000 mg) and vitamin D (800 IU). BMD at the lumbar spine and femoral neck, bone turnover markers (C-terminal telopeptide of procollagen type I [CTX], bone-specific alkaline phosphatase [BSAP]) and insulin-like growth factor-1 (IGF-1), sclerostin and DKK-1 were assessed at baseline and after 24 months. Back pain was measured by visual analog scale (VAS) every 6 months. After 24 months, TM women treated with SrR had increased their spine BMD values in comparison to baseline (p < 0.05). Moreover, they also exhibited a reduction of CTX and sclerostin levels (but not DKK-1) and exhibited an increase of BSAP and IGF-1 (p < 0.05); however, no significant changes were observed in the placebo group. In the SrR group, a reduction of back pain was observed after 18 months in comparison to baseline (p < 0.05) and after 24 months in comparison to placebo (p < 0.05). Our study reports for the first time the effects of SrR in the treatment of TM-related osteoporosis. SrR treatment improved BMD and normalized bone turnover markers, as well as lowering sclerostin serum levels.

Hypogonadism in thalassemia major patients

Despite recent advances in iron chelation therapy, excess iron deposition in pituitary gonadotropic cells remains one of the major problems in thalassemic patients. Hypogonadism, mostly hypogonadotropic hypogonadism, is usually detected during puberty. Early diagnosis and treatment are crucial for normal pubertal development and to reduce the complications of hypogonadism. The risks and benefits of hormonal replacement therapy, especially regarding the thromboembolic event, remain a challenge for providers caring for thalassemic patients.

Endocrine function and bone disease during long-term chelation therapy with deferasirox in patients with β-thalassemia major

Iron overload in β-thalassemia major (TM) typically results in iron-induced cardiomyopathy, liver disease, and endocrine complications. We examined the incidence and progression of endocrine disorders (hypothyroidism, diabetes, hypoparathyroidism, hypogonadism), growth and pubertal delay, and bone metabolism disease during long-term deferasirox chelation therapy in a real clinical practice setting. We report a multicenter retrospective cohort study of 86 transfusion-dependent patients with TM treated with once daily deferasirox for a median duration of 6.5 years, up to 10 years. No deaths or new cases of hypothyroidism or diabetes occurred. The incidence of new endocrine complications was 7% (P = 0.338, for change of prevalence from baseline to end of study) and included hypogonadism (n = 5) and hypoparathyroidism (n = 1). Among patients with hypothyroidism or diabetes at baseline, no significant change in thyroid parameters or insulin requirements were observed, respectively. Mean lumbar spine bone mineral density increased significantly (P < 0.001) and the number of patients with lumbar spine osteoporosis significantly decreased (P = 0.022) irrespective of bisphosphonate therapy, hormonal replacement therapy, and calcium or vitamin D supplementation. There were no significant differences in the number of pediatric patients below the 5th centile for height between baseline and study completion. Six pregnancies occurred successfully, and four of them were spontaneous without ovarian stimulation. This is the first study evaluating endocrine function during the newest oral chelation therapy with deferasirox. A low rate of new endocrine disorders and a stabilization of those pre-exisisting was observed in a real clinical practice setting.

Low Bone Mineral Density in Thalassemia Major: Sanjay Gandhi Post Graduate Institute Experience and a Brief Focus on Underlying Factors behind the Cause

Thalassemia major is a genetic disorder and blood transfusion is critical for survival in these patients. Over the course of the past three decades, hyper transfusion therapy in these patients has shown has dramatically extended life expectancy and improved quality of life. Unfortunately, this type of therapy also increased the incidence of complications due to iron overload. The aim of this study was to assess bone mineral density (BMD) in patients with β-thalassemia major and to determine their biochemical and hormonal profiles that may affect BMD. A cross- sectional study was carried out in Sanjay Gandhi—PGIMS, a tertiary care hospital over period of 3 years on all β-thalassemia major patients above 7 years receiving regular transfusion. Patients with transfusion dependent anaemia other than β thalassemia major were excluded. Physical examination, laboratory tests and bone density measurements were performed. Then, the data were analyzed. The total number of children over 7 years of age with β-thalassemia major receiving regular blood transfusions during the study period was 150. Mean hemoglobin was 7.8 ± 0.6 g/dL and the mean serum ferritin level 5295 ± 2736 ng/mL. Short stature was seen in 54.7% boys and 28.7% of girls. Prevalence of lumbar osteoporosis and osteopenia were 42.5% and 37.5%. Femoral osteoporosis and osteopenia were present in 32.5% and 55% of the patients. Impaired puberty, hypothyroidism, diabetes mellitus, hypoparathyroidism were observed in 26%, 18%, 7%, and 15%, of patients, respectively. Nearly 75% of patients had low bone mineral density. Bone mineral density was significantly associated with short stature (p = 0.002), hypogonadism (p = 0.006), hypoparathyroidism (p = 0.038), hypothyroidism (p = 0.044) and vitamin D deficiency (p < 0.001). High prevalence of complications among our thalassemics signifies the importance of more detailed studies along with therapeutic interventions.

Thalassemia bone disease: a 19-year longitudinal analysis

Thalassemia is an inherited disorder of alpha or beta globin chain synthesis leading to ineffective erythropoiesis requiring chronic transfusion therapy in its most severe form. This leads to iron overload, marrow expansion, and hormonal complications, which are implicated in bone deformity and loss of bone mineral density (BMD). In this 19-year retrospective longitudinal study, the relationships between BMD (determined by dual-energy X-ray absorptiometry) and risk factors for osteoporosis in 277 subjects with transfusion-dependent thalassemia were examined. The mean age at first review was 23.2 ± 11.9 years and 43.7% were male. Hypogonadism was present in 28.9%. Fractures were confirmed in 11.6% of subjects and were more frequent in males (16.5%) compared with females (7.7%). Lumbar spine (LS), femoral neck (FN), and total body (TB) Z-scores were derived. Patients with transfusion-dependent thalassemia had a significant longitudinal decline in BMD at the FN and TB. In the linear mixed-model analysis of BMD and risk factors for bone loss, FN Z-score was more significantly associated with risk factors compared with the LS and TB. The rate of decline at the FN was 0.02 Z-score per year and was 3.85-fold greater in males. The decline in FN Z-score over the last 5 years (years 15 to 19) was 2.5-fold that of the previous 7 years (years 8 to 14) and coincided with a change in iron chelator therapy from desferrioxamine to deferasirox. Hemoglobin (Hb) levels positively correlated with higher TB and LS Z-scores. In conclusion, the FN is the preferred site for follow-up of BMD. Male patients with β-thalassemia experienced a greater loss of BMD and had a higher prevalence of fractures compared with females. Transfusing patients (particularly males) to a higher Hb target may reduce the decline in BMD. Whether deferasirox is implicated in bone loss warrants further study.

Thalassemia major and sickle cell disease in adolescents and young adults

The increased longevity of patients with thalassemia and sickle cell disease (SCD) introduces new clinical challenges due to the accumulation of disease-related morbidity, psychosocial issues and health care adjustments. Patients with thalassemia major now live into adulthood without suffering heart failure but must confront delayed puberty, impaired fertility and progressive bone disease. The increased survival in SCD brings to the front previously unrecognized complications including pulmonary hypertension, silent cerebral infarcts and also reproductive dysfunction. Adolescents and young adults (AYAs) have age-related psychosocial needs in their transition from the pediatric health care environment to the adult system. In this review we present the uniquely age-related medical issues facing the AYA thalassemia and SCD cohort in their transition into adulthood.

A review of osteoporosis management in younger premenopausal women

The purpose of this review is to describe the available evidence for osteoporosis treatments in young and premenopausal women. A review of articles evaluating the treatment or prevention of osteoporosis in young (age less than 50 years) or premenopausal women was conducted. Several trials evaluating the treatment of anorexia nervosa and use of hormone therapy in those women, the use of bisphosphonates in women undergoing chemotherapy for breast cancer and the use of bisphosphonates, teriparatide and vitamin D in women with glucocorticoid-induced osteoporosis are described. Limited data were found to support the treatment of osteoporosis in women with idiopathic osteoporosis or cystic fibrosis, or after kidney transplant. The evidence for treatment of osteoporosis in premenopausal women is not nearly as robust as that for postmenopausal osteoporosis. Although fracture risk in the premenopausal population is low, women with secondary osteoporosis may benefit from treatment with various agents, depending upon the condition.

Effects of the anti-receptor activator of nuclear factor kappa B ligand denusomab on beta thalassemia major-induced osteoporosis

INTRODUCTION

Osteoporosis represents the second most common cause of endocrinopathy in patients with beta thalassemia major (BTM). Some drugs proved effective to reduce vertebral and non-vertebral fracture risk. Denosumab is a fully human monoclonal antibody to the receptor activator of nuclear factor kappa B ligand (RANKL), a member of the tumor necrosis factor receptor superfamily essential for osteoclastogenesis. The efficacy and safety of denosumab in BTM-induced osteoporosis has not been tested.

OBJECTIVE

To evaluate the efficacy and safety of anti-RANKL on the biochemical and radiological parameters of bone mineralization in patients with BTM-induced osteoporosis.

DESIGN

The study population was selected using the random sampling method from the patient's database of our thalassemia clinic. Transfusion-dependent BTM patients above 18 years with no history of treatment with bisphosphonates were randomly selected. Bone mineral density (BMD) of the lumbar spine (LS) and right femoral neck (FN) were measured by dual energy X-ray absorption (DEXA) scan using a calibrated method. Independent factors likely to be associated with low bone mass were determined and included in the analysis to ascertain possible associations.

PATIENTS AND METHODS

We studied 30 patients with BTM-induced osteoporosis as per World Health Organization criteria (T Score of less than - 1.0 being defined as osteopenic and a T Score of less than - 2.5 being referred as osteoporotic). 19 males and 11 females aged between 18 and 32 years, with full pubertal development (Tanner's stage 5) at the time of the study. Their mean serum ferritin concentration was 3557 ng ± 1488 ng/ml. Every patient underwent DEXA scan as a baseline and after 12 months of denosumab therapy. Biochemical evaluation including serum concentrations of creatinine, Na, K, calcium, phosphorus, parathormone, bone specific alkaline phosphatase and type 1 collagen carboxy telopetide (ICCT) using enzyme-linked immunosorbent assay (Nordic Bioscience Diagnostics A/S) was done at baseline, after a month and then every 3 months for 12 months after starting denosumab. 60 mg of denosumab was administered subcutaneously twice yearly for a year. The mean BMD T Scores at baseline were -2.7 at the LS and -2.1 at the FN.

RESULTS

Denosumab therapy for a year was associated with a significant increase in BMD of 9.2% (95% confidence interval [CI], 8.2-10.1) at the LS and 6.0% (95% CI, 5.2-6.7) at the FN. Denosumab treatment decreased serum ICCT levels by 56% at 1 month and normalized them in all patients at 1 year. Significant correlations were found between BMD T Score before and 1 year after denosumab in LS (r = 0.752, P < 0.001) and FN (r = 0.758 P < 0.001), respectively. The most common side effects were pain in the back and extremities (12%) and nausea (10%). Asymptomatic hypocalcaemia occurred in two patients.

CONCLUSION

Denosumab therapy for a year significantly increased BMD density at LS and FN of patients with BTM and was associated with a rapid and sustained reduction in ICCT levels. Further studies are required to confirm long-term effects of this therapy.

The bone regenerative effects of fucosterol in in vitro and in vivo models of postmenopausal osteoporosis

SCOPE

The aim of this study was to investigate the bone regenerative effects of fucosterol in estrogen-deficient ovariectomized (OVX) rats.

METHODS AND RESULTS

Bone regeneration was assessed in fucosterol-treated MG63 cells in vitro via assays for osteoblast proliferation, alkaline phosphatase, and osteoclast differentiation. Osteoblast proliferation rates, alkaline phosphatase activity, and mineralization were increased in the fucosterol-treated group. Moreover, differentiation of osteoclasts was decreased in the fucosterol-treated group. In the in vivo assay, female rats were OVX. Twelve weeks after ovariectomy, rats were divided into seven groups, each oral administrate everyday for 7 weeks. The bone mineral density of femoral bones was higher in fucosterol groups than in OVX control, and body weight was lower in fucosterol groups. Among bone-quality parameters, bone volume/total volume increased and trabecular separation decreased in fucosterol groups relative to the OVX control. Bone formation and resorption were evaluated using the serum biomarkers osteocalcin and CTx. Fucosterol tripled the level of serum osteocalcin relative to the OVX group and reduced the serum level of CTx.

CONCLUSION

These results suggest that fucosterol has the dual potentials to activate osteoblasts to stimulate bone formation and suppress differentiation of osteoclasts so as to reduce bone resorption.

Regional consensus opinion for the management of Beta thalassemia major in the Arabian Gulf area

Thalassemia syndrome has diverse clinical presentations and a global spread that has far exceeded the classical Mediterranean basin where the mutations arose. The mutations that give rise to either alpha or beta thalassemia are numerous, resulting in a wide spectrum of clinical severity ranging from carrier state to life-threatening, inherited hemolytic anemia that requires regular blood transfusion. Beta thalassemia major constitutes a remarkable challenge to health care providers. The complications arising due to the anemia, transfusional iron overload, as well as other therapy-related complications add to the complexity of this condition. To produce this consensus opinion manuscript, a PubMed search was performed to gather evidence-based original articles, review articles, as well as published work reflecting the experience of physicians and scientists in the Arabian Gulf region in an effort to standardize the management protocol.

Clinical development of neridronate: potential for new applications

Neridronate is an aminobisphosphonate, licensed in Italy for the treatment of osteogenesis imperfecta (OI) and Paget's disease of bone (PDB). A characteristic property of neridronate is that it can be administered both intravenously and intramuscularly, providing a useful system for administration in homecare. In this review, we discuss the latest clinical results of neridronate administration in OI and PDB, as well as in osteoporosis and other conditions. We will focus in particular on the latest evidence of the effect of neridronate on treatment of complex regional pain syndrome type I.

Hijikia fusiforme protects against ovariectomy-induced bone loss in rats

The prophylactic effects of Hijikia fusiforme on bone metabolism were examined using in vitro indices of bone formation and resorption. As the indices of bone formation, osteoblast proliferation and differentiation were measured through mitochondrial enzyme activity [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay] and bone marker alkaline phosphatase (ALP) activity. The aqueous extract of H. fusiforme stimulated the proliferation of the human osteoblast-like cell line MG63 and the ALP activity of the mouse osteoblast-like cell line MC3T3-E1. Moreover, extracellular matrix mineralization was accelerated by the addition of H. fusiforme. As the indices of bone resorption, differentiation of the murine macrophage/osteoclast precursor cell line RAW 264.7 by receptor activator of nuclear factor-κB ligand (RANKL) was measured as tartrate-resistant acid phosphatase-positive multinucleated cells, which were suppressed by H. fusiforme. Additionally, H. fusiforme lowered the secreted amount of RANKL that is required for the osteoclastic differentiation and activation, but the amount of osteoprotegerin as a decoy receptor for RANKL was not affected. The bone-protective effects of H. fusiforme in estrogen-deficient ovariectomized rats were also investigated. Osteoporosis was induced in female Sprague-Dawley rats by ovariectomy for 15 weeks, and then H. fusiforme was orally administered at a dose of 100  mg/kg of body weight every day for 6 weeks. Bone mineral density in the group orally administered H. fusiforme was increased, compared with ovariectomized rats, but not significantly (P>.05). Oral administration of H. fusiforme improved microarchitecture of bone in terms of bone volume (bone volume/total volume ratio) and trabecular separation (P<.05). The amounts of osteocalcin and C-telopeptide type I collagen in serum were measured as the biomarkers for bone formation and resorption. The level of osteocalcin in serum was increased, but not significantly. However, the level of C-telopeptide type I collagen in serum was significantly decreased (P<.05). When the results are taken together, the present study indicates that H. fusiforme might be useful in the treatment of osteoporosis.

Use of hormone replacement therapy for correction of high turnover bone disease in hypogonadal β-Thalassemia major patients presenting with osteoporosis: comparison with idiopathic premature ovarian failure

Osteopenia-osteoporosis syndrome (OOS) causes considerable morbidity in 60-80% β-thalassemia major (β-TM) patients. We evaluated the effect of sex hormone replacement therapy (HRT) in β-TM patients with hypogonadism presenting with OOS using premature ovarian failure (POF) for comparative purposes. We undertook a 10-year prospective study of in 50 β-TM and 375 patients with POF and OOS. All were treated with HRT for 2-5 years. We used dual X-ray absorptiometry (DEXA), and plasma type 1-collagen markers of bone turnover for monitoring of response to therapy. Our results suggest that prior to HRT, both groups had comparable degrees of OOS. Both groups had significant improvement but the POF group had normalization of spinal T scores following HRT in contrast to the β-TM patients. Femoral T scores did not normalize in both groups. These data indicate for the first time from comparative POF control studies that hypogonadism is not the only cause of OOS in β-TM.

The spine in β-thalassemia syndromes

STUDY DESIGN

Literature review.

OBJECTIVE

To present a comprehensive overview of spinal involvement in patients with β-thalassemia, aiming to orient the spinal surgeon to these potentially disabling complications.

SUMMARY OF BACKGROUND DATA

β-thalassemia, an inherited disorder of hemoglobin synthesis, is the most common monogenetic disease worldwide. Patients with thalassemia major (TM) suffer a severe anemia that requires regular blood transfusions for survival and iron chelation therapy to control transfusional iron overload. Thalassemia intermedia is a phenotype of thalassemia with a milder course and anemia, wherein most patients remain transfusion independent. Spinal involvement related to disease course and treatment is common in patients with thalassemia syndromes, yet it has not been constructively reviewed in the literature.

METHODS

Potentially relevant studies were identified from an electronic search of MEDLINE (1966 to the second week of May 2010).

RESULTS

In patients with TM, genetic and acquired risk factors lead to osteoporosis, pathologic fractures of the spine, and back pain. Osteoporosis in TM patients is progressive; thus, early diagnosis and treatment are recommended. Bisphosphonates are relatively safe and effective in this patient population. Characteristic intervertebral disc degeneration is also seen in patients with TM who have evidence of severe iron overload or those who receive the subcutaneous iron chelator deferoxamine. Spinal asymmetry and overt scoliosis are common in patients with TM. The prognosis seems favorable, with many patients showing spontaneous resolution without the need for intervention. In patients with thalassemia intermedia, ineffective erythropoiesis drives extramedullary hematopoietic tissue formation, which is mostly evident on magnetic resonance imaging. Paraspinal involvement is of greatest concern because of the associated spinal cord compression. Several treatment options have been described, including transfusion therapy, laminectomy, radiotherapy, and the use of fetal hemoglobin-inducing agents that decrease the hematopoietic drive.

CONCLUSION

Current knowledge supports that spinal involvement in patients with β-thalassemia is common and diverse yet still requires further prospective evaluation.

Bone disease and skeletal complications in patients with β thalassemia major

Increased survival in patients with β thalassemia major (TM) allowed for several complications of the disease and its treatment to manifest, one of which is bone disease. Osteoporosis in this patient population results from a variety of genetic and acquired factors. Early diagnosis and prevention are essential and several measures have been evaluated for management including bisphosphonates. Fracture prevalence in TM patients seems to be clustered in mid adulthood, and is related to vitamin D deficiency and low bone mineral density. Fracture healing in patients with TM does not seem to be different from that in normal individuals. Bone and joint pain are a common manifestation of the underlying pathophysiology or may be related to iron chelator intake. Intervertebral disc changes are seen in patients who are heavily iron overloaded or those who are chelated with deferoxamine. Spinal deformity is common in TM, yet the prognosis is benign with spontaneous resolution frequently observed. Further research is warranted to evaluate the mechanisms, clinical implications, and optimal management of bone disease in this patient population.

Treatment options for thalassemia patients with osteoporosis

Osteoporosis represents a prominent cause of morbidity in patients with thalassemia. The delay in sexual maturation, the presence of diabetes and hypothyroidism, the parathyroid gland dysfunction, the progressive marrow expansion, the iron toxicity on osteoblasts, the iron chelators, and the deficiency of growth hormone or insulin growth factors have been identified as major causes of osteoporosis in thalassemia. Adequate hormonal replacement, effective iron chelation, improvement of hemoglobin levels, calcium and vitamin D administration, physical activity, and smoking cessation are the main to-date measures for the management of the disease. During the last decade, novel pathogenetic data suggest that the reduced osteoblastic activity, which is believed to be the basic mechanism of bone loss in thalassemia, is accompanied by a comparable or even greater increase in bone resorption. Therefore, the role of bisphosphonates, potent inhibitors of osteoclast activation, arises as a major factor in the management of osteoporosis in thalassemia patients.

Changes in bone microarchitecture and biomechanical properties in the th3 thalassemia mouse are associated with decreased bone turnover and occur during the period of bone accrual

Osteoporosis and fractures occur frequently in patients with beta-thalassemias, a group of congenital hemolytic anemias characterized by decreased synthesis of the beta chain of hemoglobin. In this study, we determined the bone abnormalities of the th3 thalassemia mouse, generated by deletion of the mouse beta-chain genes. The heterozygous th3/+ mouse has moderate anemia and serves as a model of beta-thalassemia intermedia, which represents the mild thalassemia phenotype. The th3/th3 mouse has lethal anemia and is a model of beta-thalassemia major, which is characterized by life-threatening anemia requiring regular transfusions to sustain life. Compared to controls, (1) microCT of trabecular bone showed decreased bone volume fraction, number of trabeculae, and trabecular thickness in both th3/+ and th3/th3 (P < 0.05); (2) cortical bone analysis showed thinner cortices and increased marrow area in th3/+ (P < 0.05); (3) microCT abnormalities in th3/+ mice were present by 2 months and did not worsen with age; (4) histomorphometry was significant for decreased bone formation and resorption in both th3/+ and th3/th3, and expression of cathepsin K and osteocalcin from bone of both th3/+ and th3/th3 animals was reduced (P < 0.05); (5) biomechanics showed reduced maximum load, maximum moment, and structural stiffness in both th3/+ and th3/th3 (P < 0.01). In conclusion, the th3 mouse model of thalassemia manifests bone changes reminiscent of those in humans and can be used for further bone studies in thalassemia. Bone changes are associated with decreased bone turnover and develop early during the period of bone accrual.

Osteoporosis syndrome in thalassaemia major: an overview

Osteoporosis in thalassaemia major (TM) represents a prominent cause of morbidity. The mechanism of pathogenesis of bone disease (BD) in TM is multifactorial and complicated. Peak bone mass is achieved shortly after completion of puberty and normally remains stable until the third decade of life when age-related bone mass begins. Growth hormone (GH) and sex steroids play a crucial role in bone remodeling and in the maintenance of skeletal architecture during adult life. GH and insulin growth factors (IGFs) have anabolic effect in bone formation. Sex steroids act probably by increasing the expression of RANKL by osteoblastic cells and alterations in the RANK/RANKL/OPG system in favor of osteoclasts. Impaired GH secretion and lack of sex steroids in thalassemic patients due to pituitary damage, contribute to failure of achieving optimal peak bone mass. Other endocrine complications such as hypoparathyroidism and vitamin D deficiency have also a detrimental role on bones in TM. It is still questionable whether the international criteria for defining osteopenia and osteoporosis are relevant to patients with TM; also a question arises for the diagnostic methods such as DEXA scan and management of osteoporosis with known treatment protocols, in the thalassaemic patient.

Osteopenia-osteoporosis syndrome in patients with thalassemia: understanding of type of bone disease and response to treatment

With increased life expectancy, thalassaemic bone disease including osteopenia osteoporosis syndrome (OOS) is a major cause of bone pain and fragility fractures especially of the lumbar spine, which may be found in 70-80% adult patients with beta-thalassaemia worldwide, accounting for significant bone morbidity. The causes of OOS in thalassaemia syndromes are multifactorial, and the exact treatment is far from ideal. We undertook a prospective study of 34 thalassaemic patients to evaluate the effect of pamidronate and hormone replacement therapy (if hypogonadal) on bone quantity by DXA scan quality by histomorphometry of bone biopsy and bone dynamics by biochemical markers of bone turnover.Our results show that all patients had osteopenia with abnormal bones on histomorphometry before commencement of treatment. Thalassaemia major patients had high turnover bone disease and all responded favourably to treatment whereas intermedia patients had low turnover bone disease and responded poorly to treatment. Our data also showed that ICTP and PICP is a discriminatory test but histomorphometry is the only test for characterisation of bone morphology.

Prolidase activity and oxidative status in patients with thalassemia major

AIM

Prolidase is a specific imidodipeptidase involved in collagen degradation. The increase in the enzyme activity is believed to be correlated with the increased intensity of collagen degradation. The study aimed to evaluate the relationship between prolidase activity and oxidative status in patients with thalassemia major.

METHODS

Comparison was made between 87 patients diagnosed with thalassemia major and 33 healthy children of similar age and gender. Mean age of the subjects was 7.5+/-4.3 years in the group of patients with thalassemia major and 8.9+/-3.1 years in the control group. Serum prolidase activity was measured spectrophotometrically. Oxidative status was determined using total oxidant status (TOS), total antioxidant capacity (TAC), and oxidative stress index (OSI) measurement.

RESULTS

Prolidase activity was significantly increased in patients with thalassemia major (53.7+/-8.7 U/l) compared to the control group (49.2+/-7.2 U/l, P<0.001). TOS was significantly increased in the patient group (5.31+/-3.14 mmol H2O2 equiv./l) compared to the control group (3.49+/-2.98 mumol H2O2 equiv./l) and the OSI was also significantly increased in the patient group (3.86+/-3.28 arbitrary unit) compared to the control group (2.53+/-2.70 arbitrary unit) (P<0.0001 and P<0.001, respectively), while there were no significant differences between the patient (1.61+/-0.30 mumol Trolox equiv./l) and control (1.64+/-0.33 mumol Trolox equiv./l) groups with respect to TAC.

CONCLUSION

Significant increases in prolidase activity in patients with thalassemia major may constitute a key parameter in demonstrating a disorder of the collagen metabolism.

Bone disease in thalassemia: a frequent and still unresolved problem

Adults with beta thalassemia major frequently have low BMD, fractures, and bone pain. The purpose of this study was to determine the prevalence of low BMD, fractures, and bone pain in all thalassemia syndromes in childhood, adolescence, and adulthood, associations of BMD with fractures and bone pain, and etiology of bone disease in thalassemia. Patients of all thalassemia syndromes in the Thalassemia Clinical Research Network, > or =6 yr of age, with no preexisting medical condition affecting bone mass or requiring steroids, participated. We measured spine and femur BMD and whole body BMC by DXA and assessed vertebral abnormalities by morphometric X-ray absorptiometry (MXA). Medical history by interview and review of medical records, physical examinations, and blood and urine collections were performed. Three hundred sixty-one subjects, 49% male, with a mean age of 23.2 yr (range, 6.1-75 yr), were studied. Spine and femur BMD Z-scores < -2 occurred in 46% and 25% of participants, respectively. Greater age, lower weight, hypogonadism, and increased bone turnover were strong independent predictors of low bone mass regardless of thalassemia syndrome. Peak bone mass was suboptimal. Thirty-six percent of patients had a history of fractures, and 34% reported bone pain. BMD was negatively associated with fractures but not with bone pain. Nine percent of participants had uniformly decreased height of several vertebrae by MXA, which was associated with the use of iron chelator deferoxamine before 6 yr of age. In patients with thalassemia, low BMD and fractures occur frequently and independently of the particular syndrome. Peak bone mass is suboptimal. Low BMD is associated with hypogonadism, increased bone turnover, and an increased risk for fractures.

Dual-energy X-ray aborptiometry assessment in children and adolescents with diseases that may affect the skeleton: the 2007 ISCD Pediatric Official Positions

The Task Force focusing on the use of dual energy X-ray absorptiometry (DXA) in children and adolescents with diseases that may affect the skeleton reviewed over 300 articles to establish the basis for the Official Positions. A significant number of studies used DXA-based outcome measures to assess the effects of specific interventions and charted the natural history of incremental changes in bone size and mass in specific disease states in children. However, the utility of DXA in clinical practice has not been evaluated systematically, in large part due to the lack of a workable definition for childhood osteoporosis. Thus, in combination with the Official Positions addressing the diagnosis of osteoporosis in children, and the reporting of DXA results in children, this document presents clear guidelines from which clinicians and researchers alike can work. This report delineates a set of disorders in which it is appropriate to use DXA as part of the comprehensive assessment of skeletal health in children and adolescents, and provides guidance concerning the initiation of assessment and the frequency of monitoring. Importantly, this document also highlights significant gaps in our knowledge, emphasizing areas for future research.

Bisphosphonates in the treatment of thalassemia-associated osteoporosis

Thalassemia major is a common cause of skeletal morbidity, as shown by the increased fracture risk in thalassemic patients. The etiology of this bone disease is multifactorial and culminates in a state of increased bone turnover with excessive bone resorption and remodeling. Despite hormonal replacement therapy, calcium and vitamin D administration, effective iron chelation, and normalization of hemoglobin levels, patients with thalassemia major continue to lose bone mass. The increased bone turnover rate observed in thalassemic patients justifies the use of powerful anti-resorption drugs, such as bisphosphonates. To date, alendronate, pamidronate, and zoledronate seem to be effective in increasing bone mineral density and normalizing bone turnover, but more trials are necessary to evaluate their efficacy in reducing fracture risks in larger thalassemic populations.

Markers of bone metabolism in eugonadal female patients with beta-thalassemia major

Osteoprotegerin (OPG) and receptor activator of NF-kappaB ligand (RANKL) have been recently implicated in the pathogenesis of various types of osteoporosis. The aim of this study was to investigate bone turnover in eugonadal female patients with this disease and characterize the possible role of the OPG/RANKL system in thalassemia-related bone loss. Markers of bone turnover and bone mineral density (BMD) were measured in 16 eugonadal young females with beta-thalassemia major and 18 age- and sex-matched healthy controls. Bone turnover was significantly increased in thalassemic patients compared to controls but OPG was significantly higher in healthy subjects. BMD values negatively correlated with urine markers of bone resorption but not with OPG/sRANKL system.

The "lively" cytokines network in beta-Thalassemia Major-related osteoporosis

Osteoporosis affects approximately 40-50% of adult patients with beta-Thalassemia Major (beta TM). Recent data have implicated an altered modulation of the osteoprotegerin (OPG)/receptor activator of NFkB ligand (RANKL) system in the pathogenesis of beta TM-osteoporosis. OPG/RANKL system acts downstream from IL-1 alpha, IL-6 and TNF-alpha and it may be the final actor mediating the effects of these cytokines on the regulation of both postmenopausal and metabolic bone resorption. However, to date, there are no data on circulating levels of these pro-resorptive cytokines in beta TM patients. We investigated the potential relationships among these cytokines, several markers of bone turnover and bone mineral density (BMD) in beta TM patients. IL-1 alpha, IL-6 and TNF-alpha, OPG and RANKL serum levels, hemato-urinary bone remodeling markers and bone mineral density (BMD) at L2L4 and femoral neck as well as erythropoietin (EPO), 17beta-estradiol, and free-testosterone levels were measured in 30 well treated beta TM patients and in 20 healthy subjects, matched for age, sex and BMI with the patients. beta TM patients showed an altered bone turnover, with increased deoxypyridinoline (D-PYR) levels (P<0.0001), decreased osteocalcin (BGP) concentrations (<0.0001) and significantly lower lumbar (P=0.001) and femoral (P<0.05) BMD values as compared to controls. Circulating levels of IL-1 alpha (P<0.0001), TNF-alpha (P<0.0001) and IL-6 (P<0.05) were all increased in beta TM patients as compared with controls. In beta TM patients, IL-1 alpha was significantly related with D-PYR (r=0.5; P<0.05), RANKL (r=0.7; P=0.03) and IL-6 (r=0.3; P=0.006); IL-6 was also significantly correlated with D-PYR (r=0.5; P<0.05) and EPO levels (r=0.3; P=0.03); TNF-alpha showed a negative correlation with L2L4 BMD (r=-0.4; P<0.05). Our data demonstrate, for the first time, an association between increased circulating levels of pro-resorptive cytokines and an altered bone turnover in beta TM-patients, suggesting their involvement in the pathogenesis of beta TM-osteoporosis.

Unbalanced bone turnover in children with beta-thalassemia

The life expectancy of patients with thalassemia has greatly improved over the last decade as a result of regular transfusions and increased compliance with iron chelation therapy, however, this improvement is often accompanied by a series of serious complications including osteopenia and osteoporosis. The pathogenesis of these skeletal disorders is multifactorial which may be due to hormonal deficiency, compromised nutritional status, bone marrow expansion due to erythroid hyperplasia, increased iron stores or desferrioxamine toxicity. The non invasive assessment of bone turnover has markedly improved with the development of specific and sensitive markers of bone formation. The aim of this work is to assess the value of bone formation markers in patients with beta-thalassemia. To achieve this goal, 36 patients with thalassemia were recruited in this study. There were 20 males (56.6%) and 16 females (44.4%) and their ages ranged from 3 to 18 years. A control group of 20 apparently healthy subjects of matched age and sex was used. The patients were selected from the outpatient clinic and inpatients of the Hematology/Oncology Unit of Mansoura University Children's Hospital (MUCH). The selected subjects were subjected to thorough history taking, clinical examination, radiological evaluation and laboratory investigations in the form of: complete blood count, serum iron, serum ferritin, total iron binding capacity, serum calcium, serum phosphorus and estimation of bone formation markers as alkaline phosphatase and osteocalcin. The results were as follows: serum calcium level was within normal range and showed no statistical significance (p = 0.176) when compared to the control group, while serum phosphorus level was significantly higher in thalassemic patients than the controls (p = 0.002); this may reflect hypoparathyroidism. Analysis of the level of bone formation markers showed serum alkaline phosphatase levels slightly higher in patients than controls but not significant (p = 0.055), and this elevation can be referred to associated liver disease in these patients. On the other hand, osteocalcin level was significantly lower in patients than controls (p = 0.011), and this may be due to osteoblast poisoning by iron overload. In conclusion, thalassemic patients have unbalanced bone turnover between the bone formation and resorption markers and this is evidenced by non significant changes or decreased levels of bone formation markers, while bone resorption is an active process.

Conversion of red bone marrow into yellow – Cause and mechanisms

Marrow cavities in all the bones of newborn mammals contain active hematopoietic tissue, known as red bone marrow. From the early postnatal period onwards, the hematopoietic tissue, mainly in the bones of the extremities, is gradually replaced by non-hematopoietic mesenchymal cells that accumulate lipid drops, known as yellow or fatty bone marrow. For its maintenance, hematopoietic tissue depends on the support of special mesenchymal cells in the bone marrow cavity, known as hematopoietic microenvironment. Both bone-forming cells and hematopoietic microenvironment cells have common progenitors - mesenchymal stem cells (MSCs). We hypothesize that: (1) Hematopoietic microenvironment cells advance along a three stage differentiation/maturation pathway. In the first stage, they support hematopoiesis and contain no fat. In the second stage, cells accumulate fat and no longer support steady state hematopoiesis; however, under conditions of increased hematopoietic requirement, they lose fat and regain their ability to support hematopoiesis. In the last stage, hematopoietic microenvironment cells retain the appearance of yellow bone marrow and do not support hematopoiesis regardless of the state of hematopoietic requirement.(2) Since MSCs are bound to endosteal and trabecular surfaces, in tubular bones their number is relatively small, compared to cancellous bones that have much larger areas of internal bone surface. MSCs are exposed to proliferative and differentiative pressures, leading to gradual reduction of their number. Consequently, the MSC population in tubular bones becomes exhausted rather early, and the post-maturation compartment of mesenchymal cells finally consists of unipotential bone precursors maintaining bone tissue and hematopoietic microenvironment advancing towards the last (fatty) stage of differentiation. In contrast, in cancellous bones the relatively large number of MSCs does not suffer exhaustion and continues to provide newly differentiated hematopoietic microenvironment, thus maintaining red bone marrow throughout the organism's life.(3) Osteogenic and hematopoietic microenvironment differentiation pathways compete with each other for their common precursor. During the organism's growth period osteogenic stimuli prevail, while in the post-maturation period, MSC differentiation into hematopoietic microenvironment increases at the expense of differentiation into bone. This results in the reduction of bone volume and expansion of marrow cavities in hematopoietically active cancellous bones, but not in tubular bones already depleted of MSCs and not participating in hematopoiesis. Experimental and clinical data supporting these hypotheses are discussed.

Circulating osteoprotegerin and receptor activator of NF-kappaB ligand system in patients with beta-thalassemia major

Osteoporosis represents an important cause of morbidity in patients with beta-thalassemia major, and its etiology is multifactorial. Thus, the aim of this study was to characterize the possible role of the osteoprotegerin (OPG) and receptor activator of the NF-kappaB ligand (RANKL) system in thalassemia-related bone loss. Serum concentrations of OPG, soluble RANKL (s-RANKL), markers of bone turnover, and lumbar spine bone mineral density (BMD) were measured in random samples of males (n = 29; mean age +/- SEM, 24.26 +/- 1.29 years; range, 13-41 years) and females (n = 31; age, 24.59 +/- 0.95 years; range, 12-34 years) with beta-thalassemia major and in 30 healthy age-, height-, and weight-matched subjects. Thalassemic patients had significantly lower levels of OPG compared with controls (2.54 +/- 0.12 vs. 3.25 +/- 0.122, respectively; P < 0.05) and higher, albeit not statistically significantly, serum levels of s-RANKL (0.350 +/- 0.03 vs. 0.295 +/- 0.046, respectively; P < 0.05). s-RANKL correlated negatively with age (r = -0.3, P < 0.05), and OPG correlated positively with the duration of the interval between the onset of transfusions and chelation therapy (r = 0.52, P < 0.001). Regarding markers of bone metabolism, plasma values of osteocalcin correlated positively with s-RANKL (r = 0.40, P < 0.05) and negatively with OPG/s-RANKL ratio (r = -0.55, P < 0.01). In multiple regression analysis only cross-linked N-teleopeptide of type I collagen (NTX) significantly accounted for BMD. Although the OPG/RANKL system may have some clinical usefulness as a marker of bone turnover in beta-thalassemia, conventional markers of bone turnover more accurately represent changes in the BMD of these patients.

Relationship between adolescent amenorrhea and climacteric osteoporosis

OBJECTIVES

The relationship between climacteric osteoporosis and disturbances in menstrual cycle during adolescence was examined.

METHODS

Seven hundred and seventy-one questionnaires were shared out among women visiting the outpatient department for climacteric complaints for the first time between 2001 and 2004. Questions revealed the age, age at menarche and menopause, the regularity or irregularity of menstrual cycle during adolescence and adult ages. The bone mineral density was examined using the Dual Energy X-ray Absorptiometry (DEXA) method on the lumbar spine.

RESULTS

Six hundred and thirty-five of the 771 questionnaires were suitable for analysis. Osteoporosis was observed in 30.1% of the cases. Age, age at the menarche or at the menopause did not alter in the subgroups with or without osteoporosis. The incidence and severity of osteoporosis were significantly higher in patients reporting secondary amenorrhea during adolescent ages (42.1%; average BMD of the lumbar spine 71.6+/-3.9), as compared to the patients with normal cycle (30.4%; average BMD of the lumbar spine 84.8+/-7.8). No correlation between the occurrence of osteoporosis and the frequency of menstrual cycle during adulthood was observed.

CONCLUSIONS

Secondary amenorrhea during the years of adolescence might play a role in the development of more severe osteoporosis in menopause.

Effect of zoledronic acid on markers of bone turnover and mineral density in osteoporotic patients with beta-thalassaemia

Osteoporosis has emerged as an important cause of morbidity in patients with thalassemia major. Studies regarding the efficacy of bisphosphonates in thalassemia-induced osteoporosis have yielded conflicting results. We performed this prospective study to evaluate the efficacy of zoledronic acid in osteoporotic patients with thalassemia major. Patients, 29, were given 1 mg zoledronic acid intravenously every 3 months for a total of four doses. Twenty age- and sex-matched healthy blood donors served as controls. Before each infusion and 3 months after the last infusion, we determined serum levels of osteoprotegerin (OPG), N-terminal cross-linking telopeptide of type I collagen (NTX), osteocalcin (OC) and insulin-like growth factor 1 (IGF-1). Bone mineral density (BMD) of the lumbar spine was measured at baseline and after the treatment's completion. At baseline, OPG did not differ significantly between patients and controls (p=0.2), NTX were higher in patients although not significantly (p=0.139), whereas, OC levels were significantly higher and IGF-1 levels significantly lower in patients than in controls (p<0.001 and p<0.006, respectively). Zoledronic acid administration resulted in a significant decrease in NTX, OC and IGF-1 (p<0.05, p<0.001 and p<0.05, respectively) and in a significant increase in OPG and BMD (p<0.05 for both comparisons). The change in NTX, osteocalcin and IGF-1 became significant as early as 3 months after the first administration of zoledronic acid, while the change in OPG reached significance only after three infusions. Our study supports the effectiveness of bisphosphonates in the treatment of thalassemia-induced osteoporosis.

A randomized, double-blind, placebo-controlled trial of intravenous zoledronic acid in the treatment of thalassemia-associated osteopenia

Beta-thalassaemia major is associated with low bone mass and fractures. We conducted a 2 year randomized controlled trial of zoledronic acid 4 mg administered intravenously every 3 months or placebo in the treatment of beta-thalassaemia-associated osteopenla. We recruited 23 subjects from 2 university hospitals with a T score of less than -1.0 at either the lumbar spine or hip, and 23 subjects completed the study (17 M, 6 F). Treatment groups did not differ significantly with respect to bone mineral density (BMD), age, height, weight and body mass index (BMI) at baseline. BMD was assessed at baseline, 12 months and 24 months by dual-energy X-ray absorptiometry (DXA) at the lumbar spine, femoral reek, total hip and total body. After two years average lumbar spine BMD was 8.9% greater (95%CI 2.3-15.5%, P = 0.011), average femoral neck BMD was 9.1% greater (95%CI 5.5-12.7%, P < 0.0001), average total hip BMD was 9.6% greater (95%CI 6.5-12.6%, P < 0.0001) and average total body BMD was 4.7% greater (95%CI 2.7-6.8%, P < 0.0001) in the treated group compared to placebo. The absolute change in BMD from baseline to 2 years and the annualized rate of change of BMD was significantly greater in treated patients at all four sites. Age, gender, height, weight and BMI did not interact with the effect of treatment and so unadjusted data was used. The serum total ALP decreased 45% by 12 months (P = 0.004) and urinary deoxypyridinoline/creatinine ratio decreased 47% by 3 months (NS). We conclude that zoledronic acid (4 mg i.v. 3 monthly) suppresses bone turnover and increases BMD in beta-thalassaemia-associated osteopenia.

Intravenous zoledronic acid treatment in thalassemia-induced osteoporosis: results of a phase II clinical trial

Osteoporosis is an important cause of morbidity in beta-thalassemia patients. Bisphosphonates have been recently used for the treatment of osteoporosis in beta-thalassemia. This study is a prospective quasi-experimental study to assess the efficacy and safety of zoledronic acid in thalassemics with osteoporosis. Eighteen thalassemia patients with osteoporosis were given zoledronic acid 4 mg intravenously every 3 months over a period of 12 months. The efficacy of treatment was assessed by measuring (BMD) at the lumbar spine, femoral neck, and hip at baseline, 6, and 12 months. Z-score was used to measure the BMD. Other medical assessments included markers of bone formation and resorption (bone alkaline phosphatase (BAP), osteocalcin (OC), and urinary deoxypyridinoline), and the assessment of pain score, analgesic score, and performance score. Ten thalassemic osteoporotic patients were followed up only with serial BMDs as controls. Both groups had no significant difference with respect to age, gender, and baseline BMD. Patients taking zoledronic acid had a significant increase in their lumbar spine, femoral neck, trochanter, and total hip BMD measurements over the 12-month period. Patients in the control group did not have any significant change in BMD measurements. There was a significant change in the levels of OC and BAP over the 12-month follow-up period. There was also a significant decrease in the number of painful sites experienced by the patients. Treatment of thalassemic osteoporotic patients with zoledronic acid is very effective in increasing BMD at the lumbar spine and hip and in reducing pain; it is also well-tolerated.

The impact of genotype on endocrine complications in thalassaemia major

BACKGROUND

The clinical severity in thalassaemia major (TM) depends on the underlying mutations of the beta-globin gene and the degree of iron overload.

OBJECTIVE

The aim of the study was to investigate the impact of genotype on the development of endocrine complications in TM in our center.

SUBJECTS AND METHODS

126 (62 males, 64 females) thalassaemic patients of Greek Cypriot origin with a mean age of 31.2 (17-68) yr were included in the study. All patients, who were on the standard treatment protocol, were subsequently divided into two groups according to their genotype, group A (92): TM with no mitigating factor and group B (34): TM carrying one or more mitigating factors in the beta- and/or alpha-globin genes. Iron overload calculation was based on the amount of red cell consumption and the mean ferritin level over a 12-year period. Statistical analysis was performed with the SPSS program.

RESULTS

Patients in group A, who were consuming larger amounts of blood on transfusions, were more likely to develop hypogonadism (P = 0.001) compared with patients in group B, despite their similar mean ferritin levels. The incidence of other endocrinopathies (short stature, hypothyroidism, and diabetes mellitus) was similar in the two groups. The prevalence of hypothyroidism in splenectomized patients was significantly higher (P = 0.005), whereas the presence of hypogonadism, impaired glucose homeostasis and insulin resistance, although more frequent, was not statistically significant. The clinical severity of TM had no impact on bone mineral density (BMD) in both men and women. BMD was only influenced by gonadal function.

CONCLUSIONS

This study demonstrates that the underlying genetic defect in TM is a contributing factor for gonadal dysfunction, because the patients with the more severe defects have a greater rate of iron loading through higher red cell consumption.

Low serum levels of 25-hydroxy vitamin D in adults affected by thalassemia major or intermedia

Adult thalassemic patients have reduced bone mass due to disturbances in several different mechanisms affecting bone turnover. To determine if vitamin D deficiency contributes to the low bone mass of adult thalassemic subjects, we studied serum 25-OH-vitamin D levels in 90 patients (age ranging between 21 and 48 years) affected with thalassemia major (TM) and 35 (age 21-56 years) with thalassemia intermedia (TI). TM patients had been receiving regular transfusions from the age of 2 years and had increased serum ferritin, glutamic oxalacetic transaminase, glutamic piruvic transaminase as well as low bone density (L1-L4 Z score -2.07 +/- 0.2). TI patients did not receive transfusions, but their ferritin levels were increased as well (520.3 +/- 138,1). 8 TM patients (10.1%) and 4 TI (11.4%) had serum 25-OH-vitamin D less than 10.4 ng/ml and were considered presenting an absolute deficiency of vitamin D. Mean 25-OH-vitamin D was significantly (P < 0.01) lower in both TM and TI patients (20.3 +/- 0.7 ng/ml and 20.9 +/- 2.3 ng/ml, respectively) than in 100 healthy control subjects of similar age (25.2 +/- 1 ng/ml). 1,25-OH-vitamin D levels were in the normal-lower levels (45.15 +/- 1.5 mg/dl), while 24 H urinary calcium was below the normal range (15.75 mg/dl). In TM patients, the 25-OH-vitamin D levels correlated negatively with age (P < 0.05) and with serum ferritin (P < 0.05). TM and TI patients with low 25-OH-vitamin D levels (<17.8 ng/ml) presented higher serum ferritin levels (P < 0.01) and higher PTH (P < 0.05) compared to those with normal vitamin D. Moreover, TM patients with low 25-OH-vitamin D levels were significantly older (P < 0.05) and had higher GPT (P < 0.05) than patients with normal vitamin D. In conclusion, calcium metabolism is frequently impaired in adult thalassemic patients. An early and effective medical treatment should be taken in consideration by the clinician in order to improve the bone health in these patients.

Hypoparathyroidism in transfusion-dependent patients with beta-thalassemia

Hypoparathyroidism is thought to be a rare consequence of iron overload seen in beta-thalassemic transfused patients. This study was conducted to determine the prevalence of hypoparathyroidism in a large number of beta-thalassemic patients, and its potential correlation with the presence of other endocrinopathies caused by iron overload. Serum and urine biochemical parameters were measured in 243 thalassemic patients (136 females and 107 males) in order to determine the prevalence of hypoparathyroidism and evaluate bone turnover. The patients were divided into two groups according to the presence of hypoparathyroidism. We compared the prevalence of other endocrinopathies and disease complications in the two groups. Hypoparathyroidism was detected in 13.5% of the patients (33 subjects; 17 males and 16 females). Serum-intact parathyroid hormone, and total and ionized calcium were significantly lower, while phosphorus was significantly higher in thalassemic patients with hypoparathyroidism. The reduction in BMD was more prominent in normal thalassemic patients (Z score = -2.246 +/- 0.97) compared with those with hypoparathyroidism (Z score = -1.975 +/- 0.89), although the difference was not statistically significant. Disturbed glucose metabolism was more common in patients with hypoparathyroidism (P < 0.05). In addition, heart dysfunction was statistically more frequent in this group (odds ratio = 2.51, P < 0.05). Hypoparathyroidism is a not infrequently observed complication in thalassemic patients. Since the concentration of ferritin is not a valuable tool in the prediction of the development of hypoparathyroidism, parathyroid function should be tested periodically, particularly when other iron overload-associated complications occur.

Soft tissue density variations in thalassemia major: a possible pitfall in lumbar bone mineral density measurements by dual-energy X-ray absorptiometry

Osteoporosis is common in patients with thalassemia major. A 16-year-old patient with thalassemia major was referred for evaluation of osteoporosis. The results of dual-energy X-ray absorptiometry in a patient with thalassemia major are presented. The patient underwent measurements of the spine in both AP and lateral position. The DXA scan of the spine in AP projection showed diffusely increased density overlying the lower thoracic and upper lumbar vertebrae. The overall density of L(2)-L(4) was 0.6465 g/cm(2) (4.93 SD as compared with young adults). The DXA scan of the spine in lateral projection showed diffusely increased density in front part of the spine. The BMD of the L(3) vertebra was 0.3669 g/cm(2) (0.30 SD as compared with young adults). It is important to interpret the images visually in order to obtain true values of BMD, and preclude invalid BMD measurements.