Prevalence of abnormal bone density of pediatric patients prior to blood or marrow transplant

Investigating the bone mineral density in children with solid tumors in southern Iran: a case-control study

Along with increasing childhood cancer survival, there is increasing concern about its chronic complications. We showed that 20.5 and 45.9% of children with solid tumors in southern Iran had low bone mass for chronological age in lumbar and femoral area, which was associated with serum ferritin and hemoglobin. 52.4% of these children had vitamin D deficiency, as well.

PURPOSE/INTRODUCTION

Along with increasing the childhood cancer survival, there is increasing concern about the chronic complications of the disease and the related therapies. This study aims to compare the vitamin D status and bone mineral apparent density (BMAD) of these children with healthy ones and assess some possible associated factors.

METHOD

This case-control study enrolled 50 children with solid tumors and their age- and sex-matched controls. Dual-energy X-ray absorptiometry was used to assess bone mineral density. Body mass index, puberty, physical activity, sun exposure, and biochemical data were assessed.

RESULTS

52.4% of children with solid tumors had vitamin D deficiency, and there was no significant difference between the prevalence of vitamin D deficiency in patients and controls (P = 0.285). The prevalence of low bone mass for chronological age in lumbar area was 20.5 and 12.5% in patients and controls, respectively (P = 0.399). Lumbar spine BMD was associated with hemoglobin level (r = 0.468, P = 0.049), while low bone mass in femoral neck was associated with serum ferritin (859 ± 1037 in low bone mass vs. 178 ± 264 in without low bone mass, P = 0.039).

CONCLUSION

Vitamin D deficiency and low bone mass are prevalent among Iranian children with solid tumors. Future studies are warranted to investigate the best strategies to prevent and treat vitamin D deficiency and low bone mass in children surviving cancer.

Relationship between endocrine changes and bone markers in pediatric thalassemic patients after hematopoietic stem cell transplantation

BACKGROUND

Beta thalassemia major and its treatment by hematopoietic stem cell transplantation can have deleterious effects on bone integrity and a main part of such effects is due to their deleterious effects on endocrine systems. So, we assessed the effects of endocrine changes during HSCT (Hematopoietic Stem Cell Transplantation) on growing bones of pediatric thalassemic patients.

METHODS

Bone-specific alkaline phosphatase and osteocalcin (bone formation markers), N-terminal telopeptide (NTX, bone resorption marker), calcium (Ca), phosphorus (P), alkaline phosphatase (Alk ph), parathyroid hormone (PTH), vitamin D (vit D), prolactin, luteinizing hormone (LH), follicle-stimulating hormone (FSH), thyroxine (T4), triiodothyronine (T3), thyroid-stimulating hormone (TSH), insulin-like growth factor 1 (IGF-1), testosterone (in males) or estradiol (in females), measured in 20 major thalassemic patients with mean age of 10.8±3.9 years. Parameters at the baseline (before HSCT), and 1 month and 3 months after HSCT.

RESULTS

After stem cell transplantation, changes of mean serum levels of NTX, osteocalcin, prolactin, LH, T4, IGF-1, testosterone (in males), Ca, Alk ph, PTH, and vit D were not significant, but bone specific Alk ph, P, T3, TSH, FSH and estradiol changed significantly (P=0.013, P=0.001, P=0.48, P=0.02, P=0.04 and P=0.001, respectively). After one month, there was a significant positive relationship between osteocalcine and T3 (p= 0.009). After 3 months, also, there was a significant positive relationship between osteocalcine and T3 and T4 as well as a negative one with IGF-1 (P<0.001, P<0.02 and P<0.03, respectively).

CONCLUSIONS

Endocrine disorders do not appear to have an overall positive or negative effect on bone metabolism (anabolism or catabolism) in HSCT pediatric thalassemic patients in short term (three months).

Changes in bone mineral density and bone turnover markers in patients undergoing hematopoietic stem cell transplant

INTRODUCTION

Hematopoietic stem cell transplant (HSCT) is frequently complicated by endocrine abnormalities and loss of bone mass. This prospective study was conducted to evaluate the bone loss post-HSCT.

MATERIALS AND METHODS

A total of 50 patients was evaluated pretransplantation, and 25 had HSCT (17 males, 8 females; 19 allogenic, 6 autologous). Bone mineral density (BMD) and bone markers were measured at baseline, 3-6 months and 12 months.

RESULTS

The mean age and body mass index were 25.1 ± 16.3 years and 19.4 ± 4.5 kg/m(2), respectively. There were 15 adults (60%), and 10 adolescents (40%). There was a significant decline in BMD from the baseline at total femur (-8.7%; P < 0.0001), femoral neck (-5.0%; P = 0.003), femoral trochanter (-6.0%; P = 0.001), and Ward's triangle (-9.9%; P < 0.0001) at 6 months posttransplantation. From the 6 months to 12 months, there was a significant improvement in BMD at above sites except at Ward's triangle. The decline in BMD was nonsignificant at the whole body (-0.3%, P = 0.748) and the lumbar spine (-2.7%, P = 0.130) at 6 months posttransplant. Younger patients with allogenic graft and steroid use are more likely to have significant loss of BMD at hip posttransplant. Serum osteocalcin decreased, and N-telopeptide increased at 3-6 months, which return to baseline at 1-year posttransplant.

CONCLUSIONS

A significant bone loss is observed at 6 months in patients with post-HSCT. The bone loss occurs predominantly at cortical bone. There is recovery of bone mass at 12 months posttransplant except at Ward's triangle. Bone loss after HSCT is multifactorial.

Comparison of bone mineral density changes in pediatric thalassemic patients with and without hematopoietic stem cell transplant

OBJECTIVES

Beta thalassemia major is a genetic hemoglobin disorder that affects bone density. The disease leads to deteriorating bone structure but can be treated with hematopoietic stem cell transplant. We aimed to assess bone mineral density changes in pediatric beta thalassemia major patients who had undergone a hematopoietic stem cell transplant compared with similarly affected patients who had not undergone a hematopoietic stem cell transplant.

MATERIALS AND METHODS

Forty beta thalassemia major patients, 20 transplant and 20 nontransplant, younger than 16 years of age were enrolled. The mean age of transplant patients was 8.15 years and nontransplant patients was 9.5 years (P = .242). The female:male ratio was 1:1 in both groups. None of the patients reached puberty during this study. Bone mineral density was evaluated in transplant patients before and 1 year after hematopoietic stem cell transplant. Bone mineral density of nontransplant patients also was evaluated 1 year after their initial bone mineral density test. A Norland XR-46 densitometer was used to make all bone mineral density measurements. None of the patients had a z score < -2.

RESULTS

Mean bone mineral density changes in the femur and spine during this study were 0.008 ± 0.075 g/cm2 and 0.048 ± 0.045 g/cm2 in transplant patients and 0.045 ± 0.072 g/cm2 and 0.036 ± 0.058 g/cm2 in nontransplant patients. No significant differences between bone mineral density changes in transplant and nontransplant patients were detected during the study.

CONCLUSIONS

No significant effects on bone mineral density were detected in hematopoietic stem cell transplant pediatric beta thalassemia major patients compared with similarly affected nontransplant patients. Studies of longer duration may be required to identify significant changes in bone mineral density in hematopoietic stem cell transplant patients.

Development of an evidence-based clinical guideline for age-appropriate screening, prevention, and management of bone abnormalities in children post-hematopoietic stem cell transplant

Musculoskeletal complaints, pain, and weakness are common among children post-hematopoietic stem cell transplant (HSCT). Bone abnormalities include decreased bone mineral density and avascular necrosis, both affecting ambulation and quality of life for survivors. Several risk factors for both disorders among adults have been described along with suggested interventions. However, similar recommendations for screening and management of bone abnormalities among children and adolescents post-HSCT are not clearly defined. A review of the literature using PubMed, CINAHL, National Guideline Clearinghouse, and Cochrane Collection databases identified a paucity of reports specific to the management of bone abnormalities in children and adolescents post-HSCT. Although guidelines for evaluation of bone health in pediatric patients with cancer exist, none specifically address early screening and prevention. The purpose of this article is to provide a review of the literature on current evidence for age appropriate screening, prevention, and management of bone abnormalities in children post-HSCT and to present a clinical guideline for bone abnormalities in children post-HSCT used in a hospital-based outpatient center.

Screening, prevention and management of osteoporosis and bone loss in adult and pediatric hematopoietic cell transplant recipients

Long-term survivors of hematopoietic cell transplantation (HCT) are at risk for loss of bone mineral density (BMD) and subsequent osteoporosis. There is a lack of clear guidelines for the screening, prevention and treatment of bone loss after HCT. We reviewed the prevailing literature and provide guidelines developed by our center for the screening and management of this complication. Bone loss occurs predominantly within the first 6-12 months after autologous and allogeneic HCT. Recovery first occurs in the lumbar spine and is followed by a slower recovery of BMD in the femoral neck. BMD may not return to baseline levels in patients with continuing exposure to corticosteroids and calcineurin inhibitors. All HCT recipients should be advised general interventions to reduce fracture risk including adequate intake of calcium and vitamin D. We recommend screening all adult allogeneic and autologous HCT recipients with dual-energy X-ray absorptiometry 1 year after transplantation. Patients at high risk for bone loss (for example, patients receiving ≥ 5 mg of prednisone equivalent daily for > 3 months) can be screened earlier (for example, 3-6 months after HCT). Where indicated, bisphosphonates or other anti-resorptive agents (for example, calcitonin) can be used for prevention or treatment of osteoporosis in adult HCT recipients. Pediatric HCT recipients should be referred to a pediatric endocrinologist for evaluation and treatment of bone loss. There remain several areas of uncertainty that need further research in adult and pediatric HCT recipients, such as the optimal timing and frequency of screening for loss of bone mineral density, relationship of bone loss with risk of fractures, selection of appropriate patients for pharmacologic therapy, and optimal dosing schedule and duration of therapy with anti-resorptive agents.

Bone mineral density after bone marrow transplantation in childhood: measurement and associations

This study examined the bone mineral density (BMD) of 46 (median age 16.3, 8-29) survivors of autologous and allogeneic bone marrow transplantation (BMT). Areal (g/m2) BMD was acquired with dual energy x-ray absorptiometry and volumetric (g/cm3) BMD values were calculated. Abnormal BMD was identified in 24% (11/46) of survivors with areal measures and 22% (10/46) with volumetric measures. Comparison of areal and volumetric BMD revealed the measures were highly correlated (r = 0.73, p<0.001) but clinical diagnosis of osteopenia/osteoporosis were not consistent. Volumetric z-scores were higher for 7/8 of the survivors who were < 3rd percentile for height. Associations of BMD and body composition and disease and treatment factors were assessed with multiple linear regression. When controlling for other significant associations and cumulative steroid dose, the body composition measure of fat mass index (FMI) was associated with higher volumetric BMD z-scores (CI: 0.006, 0.193; p = 0.037). CNS irradiation (CI: -1.710,-0.200; p = 0.015), age at time of testing (CI: -0.116, -0.024; p = 0.004) and female sex (CI: -1.375, -0.155; p = 0.015) were associated with lower volumetric BMD z-scores.

CONCLUSIONS

Childhood BMT survivors are at risk for diminished BMD. Areal and volumetric DEXA derived measures of BMD are highly correlated and volumetric measures may correct for underestimation of BMD in BMT survivors who are small for age. Survivors who received CNS irradiation, are older and female may be at greater risk for diminished BMD while fat mass is associated with higher BMD in childhood BMT survivors.

The burden of cure: long-term side effects following hematopoietic stem cell transplantation (HSCT) in children

Children who survive hematopoietic stem cell transplantation (HSCT) are at risk for an inordinate number of long-term side effects. Late effects can be secondary to the underlying diagnosis for which the transplant is performed, prior treatment of the disease, the transplant preparative regimen, treatment of the complications of transplant, and immunologic interactions between the graft and the host. This article describes the risks and manifestations of the most commonly reported late effects in survivors of pediatric HSCT.