Long-lasting bone damage detected by dual-energy x-ray absorptiometry, phalangeal osteosonogrammetry, and in vitro growth of marrow stromal cells after allogeneic stem cell transplantation

Effects of antiepileptic therapy on bone mineral status evaluated by phalangeal quantitative ultrasound in pediatric patients with epilepsy and motor impairment

BACKGROUND

In epileptic patients with motor disability, it's difficult to disentangle the effects of antiepileptic drugs (AEDs) on bone health from those provoked by impaired mobility. The aim of this study was to evaluate the effects of AEDs on bone mineral status by phalangeal quantitative ultrasound (QUS), a no-radiation and non-invasive method, in pediatric patients with motor impairment and epilepsy.

METHODS

We enrolled 56 patients (31 females, 25 males) with epilepsy and motor impairment and 24 children with only motor disability (13 females, 11 males). Patients were stratified by Gross Motor Function Classification System Scale (GMFCS) in 4 groups: group A1 with epilepsy and mild motor impairment (GMFCS levels I-II), group A2 with only mild motor impairment, group B1 with epilepsy and severe motor impairment (GMFCS levels III-V), group B2 with only severe motor impairment. The bone mineral status was evaluated by phalangeal QUS and amplitude-dependent speed of sound (AD-SoS) Z-score was calculated for each patient.

RESULTS

The four groups showed no significant differences in age, gender and 25-hydroxyvitamin D levels. The group B1 had a statistically lower amplitude-dependent speed of sound Z-score as compared to group A2 (P<0.05). The multivariate analysis of independent factors revealed a significant correlation between amplitude-dependent speed of sound Z-score and Gross Motor Function Classification System levels (P=0.004). The mean Z-score value decreased by 0.53, increasing the motor impairment.

CONCLUSIONS

The bone mineral status measured as AD-SoS strongly correlates with severity of motor disability evaluated by GMFCS as compared to antiepileptic therapy and 25-hydroxyvitamin D levels.

Endocrine sequelae of hematopoietic stem cell transplantation: Effects on mineral homeostasis and bone metabolism

Hematopoietic stem cell transplantation (HSCT) is an established therapeutic strategy for the treatment of malignant (leukemia and lymphoma) and non-malignant (thalassemia, anemia, and immunodeficiency) hematopoietic diseases. Thanks to the improvement in patient care and the development of more tolerable conditioning treatments, which has extended the applicability of therapy to the elderly, a growing number of patients have successfully benefited from HSCT therapy and, more importantly, HSCT transplant-related mortality has consistently reduced in recent years. However, concomitantly to long term patient survival, a growing incidence of late HSCT-related sequelae has been reported, being variably associated with negative effects on quality of life of patients and having a non-negligible impact on healthcare systems. The most predominantly observed HSCT-caused complications are chronic alterations of the endocrine system and metabolism, which endanger post-operative quality of life and increase morbidity and mortality of transplanted patients. Here, we specifically review the current knowledge on HSCT-derived side-effects on the perturbation of mineral metabolism; in particular, the homeostasis of calcium, focusing on current reports regarding osteoporosis and recurrent renal dysfunctions that have been observed in a percentage of HSC-transplanted patients. Possible secondary implications of conditioning treatments for HSCT on the physiology of the parathyroid glands and calcium homeostasis, alone or in association with HSCT-caused renal and bone defects, are critically discussed as well.

Osteonecrosis of the jaw secondary to haematopoietic stem cell transplantation

Osteonecrosis of the jaw (ONJ) is necrosis of mandibular or maxillary bone, which sometimes leads to bone exposure and sequestration. There is evidence that the microenvironment of the marrow stromal system is severely and irreversibly damaged after haematopoietic stem cell transplantation (HSCT) leading to a deficit in the quantity and quality of osteoblastic progenitors, compromising the ability to regenerate a normal osteogenic cell population and abnormality in bone remodelling/turnover. While osteonecrosis of the appendicular skeleton is a common complication after HSCT, there have been no reports of an association with ONJ. This is a report of the first case of ONJ secondary to HSCT in a 69-year-old woman who developed a unique pattern of osteonecrosis involving all four quadrants of the jaw 2 months after allogeneic stem cell transplantation.

Long-term Follow-up of Hematopoietic Stem Cell Transplant Survivors: A Focus on Screening, Monitoring, and Therapeutics

Annually, ~50,000 patients undergo hematopoietic stem cell transplantation (HCT) worldwide with almost 22,000 of these patients receiving HCT in the United States. HCT is a curative option for a wide range of hematologic malignancies, and advances in transplantation medicine have resulted in an increase in HCT survivors. It is anticipated that the number of HCT survivors will more than double from 242,000 in 2020 to ~500,000 in 2030. Survivors of HCT are at an increased risk of developing late complications due to exposure to chemotherapy and/or radiation in the pre-, peri-, and post-HCT phases and these cumulative exposures have the potential to damage normal tissue. This tissue damage leads to the early onset of chronic health conditions resulting in premature mortality in HCT survivors, who have a 15-year cumulative incidence of severe or life-threatening chronic health conditions exceeding 40%. Due to the significant burden of morbidity in HCT survivors and the delay in the development of long-term complications, this delicate patient population requires life-long monitoring due to the risk for neuropsychological, cardiac, pulmonary, renal, hepatic, ocular, skeletal, cardiac, endocrine, fertility, and sexual health complications, as well as secondary neoplasms. This review will focus on recent advances in screening, monitoring, and therapeutics for late-occurring or long-term complications in HCT survivors.

To D or not to D: vitamin D in hematopoietic cell transplantation

Vitamin D plays an essential role in bone health, immune tolerance, and immune modulation. Autologous and allogeneic hematopoietic cell transplantation (HCT) recipients are at increased risk of vitamin D deficiency, which may increase risks of bone loss and fracture, graft-versus-host disease (GVHD), and relapse, and can delay hematologic and immune recovery following HCT. Growing evidence indicates that vitamin D may have a role as an immunomodulator, and supplementation during HCT may decrease the risk of GVHD, infection, relapse, and mortality. In this paper, we review the role of vitamin D and its association with HCT outcomes and discuss prevention and treatment of vitamin D deficiency after HCT in adult recipients. We review the role of monitoring of vitamin D levels pre- and post-HCT and its supplementation in appropriate patients. We also review the use of bone densitometry prior to HCT and in long-term follow-up and the treatment of osteoporosis in this high-risk population.

Managing Endocrine Disorders in Adults After Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) has become a potentially curative therapy for an increasing number of malignant and non-malignant conditions. As survival rates continue to improve, the focus of patient care has shifted from managing not only immediate but also long-term complications. Endocrine disorders are among the most prevalent late effects following HSCT. Detecting and treating such conditions offer new challenges, as well as opportunities to reduce preventable morbidity and mortality associated with HSCT. Our objective is to summarize recent literature and describe practical approaches to screening for and managing endocrine-related late effects. We focus on dyslipidemia, diabetes, thyroid disorders, osteoporosis, and hypogonadism. Mechanisms, monitoring, and management recommendations for each disorder are outlined. Growing data on these disorders in the post-transplant setting highlight the need for future study and evidence-based guidelines.

Quantitative Ultrasound of Proximal Phalanxes in Childhood Acute Lymphoblastic Leukemia Survivors

Reduced bone mineral density (BMD) is a well-known complication in childhood acute lymphoblastic leukemia (ALL) survivors; the optimal method to assess BMD is still debated. We studied BMD by quantitative ultrasound (QUS) in 72 ALL survivors, and evaluated any correlation with cumulative doses of steroids and cytotoxic agents. Mean age at diagnosis was 61±45 months, while mean age at QUS was 318.3±129.6 months; mean period of follow-up was 41.2±37.8 months. Mean amplitude-dependent speed of sound z-score was -1.22±1.19. Ten survivors (13.8%) presented a z-score below -2 SD. A negative correlation was found between amplitude-dependent speed of sound z-score and age at diagnosis (P=0.01). A positive correlation was observed with length of follow-up (P=0.01). No correlation was found with cytotoxic drugs. This study represents the largest cohort of childhood ALL survivors studied by QUS. Our results suggest that QUS for its characteristics of being radiation free may be an effective option to assess BMD in pediatric age. In addition, our data outline the importance to improve the awareness about the specific expression of this complication in the pediatric age, concerning the major determinants of bone impairment, which are the disease itself and the phase of bone growth when the disease occurs.

Characterization and Risk Factor Analysis of Osteoporosis in a Large Cohort of Patients with Chronic Graft-versus-Host Disease

The National Institutes of Health Chronic Graft-versus-Host Disease (cGVHD) Consensus Project Ancillary and Supportive Care Guidelines recommend annual assessment of bone mineral density (BMD) to monitor bone health. The study of osteoporosis in patients with cGVHD has been limited to small numbers of patients, and the guidelines are based on experience with other chronic diseases and expert opinion. We hypothesized that the prevalence of osteoporosis is high in a cohort of 258 patients with moderate to severe cGVHD because of prolonged exposure to risk factors for osteoporosis after allogeneic hematopoietic stem cell transplantation. We defined osteoporosis using BMD criteria (T-score ≤-2.5) at 3 anatomic sites-the femoral neck (FN), lumbar spine (LS), and total hip (TH)-and characterized risk factors through univariate and multivariate analyses. We found that low body weight (FN, P < .0001; LS, P = .0002; TH, P < .0001), malnutrition (FN, P = .0002; LS, P = .03; TH, P = .0076), higher platelet count (FN, P = .0065; TH, P = .0025), higher average National Institutes of Health organ score (FN, P = .038), higher prednisone dose (LS, P = .032), lower complement component 3 (LS, P = .0073), and physical inactivity (FN, P = .01) were associated with osteoporosis in at least 1 site. T-scores were significantly lower in the FN compared with the LS or TH (P < .0001 for both). The prevalence of osteoporosis and osteopenia was high (17% and 60%, respectively), supporting current recommendations for frequent monitoring of BMD. The association of higher platelet count in patients with cGVHD and osteoporosis has not been reported previously and represents a new area of interest in the study of osteoporosis after allogeneic hematopoietic stem cell transplantation.

Factors influencing the late phase of recovery after bone mineral density loss in allogeneic stem cell transplantation survivors

Accelerated bone mineral density loss (BMDL) occurs early after allogeneic stem cell transplantation (SCT) and is related to factors such as steroids and chronic GvHD. In order to understand the natural history of BMDL of SCT in the longer term, we evaluated a longitudinal cohort of 148 survivors with a median follow-up of 12 years (range 3-22 years). All women received hormone replacement therapy, and routine calcium/vitamin D supplementation was recommended but ∼50% of patients still had suboptimal vitamin D levels and bisphosphonates were rarely utilized. BMD significantly improved from 5 to 20+ years but the femoral neck and forearm remained vulnerable sites. Younger age, higher pretransplant body mass index (BMI) and increment in BMI post transplant were significantly associated with increased BMD and protected against osteopenia/osteoporosis. These findings support consideration of BMD loss in SCT survivors in two phases, an early phase of BMD loss (3-5 years) followed by a later phase of BMD recovery, with different protective and aggravating factors. Treatment- and transplant-related factors (such as steroids, immunosuppressives, chronic GvHD, vitamin D) are known to impact the early phase of BMD loss but age and BMI are more influential in the late phase of BMD recovery.

Symptoms and management of pediatric patients with incurable brain tumors in palliative home care

INTRODUCTION

Brain tumors have the highest disease-related mortality rate of all pediatric cancers. The goal of this study was to determine whether all children with incurable brain tumors cared for by a pediatric palliative care team in a home setting suffer from the same symptoms towards the end of their lives or whether there are differences between the tumor localizations with implications for palliative care.

PATIENTS AND METHODS

This study was conducted as a retrospective, single center chart review including all patients treated between January 1st 2000 and December 31st 2013.

RESULTS

70 children, adolescents and young adults were included in the analysis. Symptom burden was high with a mean number of symptoms of 7.2 per patient. 74% of the symptoms already existed one week before death. Within the last week of life, impaired consciousness (75.7%) most often occurred. Furthermore, symptoms considerably depended on tumor localization. Patients with supratentorial tumors presented more frequently with seizures (p < 0.05), coma (p < 0.01), nausea and emesis (p < 0.01). Ataxia (p < 0.001) occurred most frequently in infratentorial tumors and speech disturbances (p < 0.05), cranial nerve paralysis (p < 0.001), and tetraparesis (p < 0.001) in brain stem tumors. 84.3% of the patients needed analgesics, only 64.4% WHO class III analgesics. Anticonvulsants were given more often in supratentorial tumors (p < 0.01).

CONCLUSIONS

Caring for a dying child suffering from a brain tumor needs increased awareness of the neurological deterioration. The symptom pattern strongly depends on the tumor localization and significantly differs between supratentorial, infratentorial and brain stem tumors.

Human Wharton's jelly stem cells, its conditioned medium and cell-free lysate inhibit the growth of human lymphoma cells

Several groups have reported that primitive mesenchymal stem cells from the gelatinous matrix of the Wharton's jelly of the human umbilical cord (hWJSCs) possess tumoricidal properties and inhibit the growth of solid tumours such as human mammary carcinoma, ovarian carcinoma and osteosarcoma. This unique characteristic led to the hypothesis that hWJSCs serve as a natural defence against migrating cancer cells from mother to fetus thus explaining why tumorigenesis in the fetus is rare. However, it is not known whether non-solid malignant hematopoietic cells are also inhibited by hWJSCs and what the exact tumoricidal mechanisms are. We therefore evaluated the influence of hWJSCs and its extracts on Burkitt's lymphoma cells. Cell proliferation (BrdU and Ki67+), viability (MTT) and cell death (Annexin V-Propidium iodide and live/dead) assays showed significant inhibition of lymphoma cell growth after 48 h exposure to hWJSCs or its extracts compared to controls. Increased cell death was observed at sub-G1 and S and decreased proliferation at G2/M phases of the mitotic cycle. Superoxide dismutase and hydrogen peroxide activity were significantly increased and glutathione peroxidase significantly decreased in treated lymphoma cells. Time lapse imaging and confocal z-stack images showed yellow fluorescent in situ hybridization (FISH) signals of lymphoma cell Y chromosomes within the cytoplasm of female red labelled hWJSCs. We hypothesize that the growth of lymphoma cells is inhibited by the molecules secreted by hWJSCs that use oxidative stress pathways to induce cell death followed by engulfment of the apoptotic remains of the lymphoma cells by the hWJSCs.

Increased incidence of fractures in recipients of hematopoietic stem-cell transplantation

PURPOSE

The number of long-term survivors after hematopoietic stem-cell transplantation (HSCT) for malignant and nonmalignant disorders is increasing, and late effects are gaining importance. Osteoporosis and fractures can worsen the quality of life of HSCT survivors, but the burden of the disease is unknown.

PATIENTS AND METHODS

We conducted a retrospective study of patients older than age 18 years who underwent an HSCT at The University of Texas MD Anderson Cancer Center from January 1, 1997, to December 31, 2011, and were observed until December 31, 2013, to ascertain occurrence of fractures. Cumulative incidence rates of fractures were calculated with death as a competing risk. Age- and sex-specific incidence rates per person-year of fracture were compared with those of the US general population by using estimated rates from the 1994 National Health Interview Survey and the 2004 National Hospital Discharge Survey.

RESULTS

A total of 7,620 patients underwent an HSCT from 1997 to 2011 at the MD Anderson Cancer Center of whom 602 (8%) developed a fracture. Age, underlying disease, and HSCT type were significantly associated with fracture. Age- and sex-specific fracture incidence rates after HSCT were significantly greater than those of the US general population in almost all subgroups. The striking difference was an approximately eight times greater risk in females and approximately seven to nine times greater risk in males age 45 to 64 years old when compared with the National Health Interview Survey and National Hospital Discharge Survey fracture rates.

CONCLUSION

The incidence of fractures is compellingly higher after HSCT.

Impact of denosumab on bone mass in cancer patients

Cancer therapy-induced bone loss (CTIBL) is a form of secondary osteoporosis associated with systemic chemotherapy and hormonal ablation therapy. The monitoring and treatment of CTIBL is an important component of comprehensive cancer care, especially for patients with curable disease and long life expectancies. Whereas oral bisphosphonates remain the most commonly used therapeutic option for CTIBL, additional treatment options may be required for patients who do not respond adequately or are intolerant to bisphosphonates, have renal insufficiency, or are receiving treatment with nephrotoxic medications. For these patients, denosumab, a monoclonal antibody targeting the receptor activator of nuclear factor-κB ligand (RANKL), offers an effective and well-tolerated alternative. Several recent randomized trials have examined the use of denosumab as treatment for CTIBL associated with hormone ablation therapy for breast and prostate cancer. Recent data suggest a possible role for RANKL inhibitors in both chemoprevention and the prevention of cancer recurrence through direct effects on breast tissue and breast cancer stem cells. The outcomes of several international Phase III clinical trials currently underway will help clarify the role of denosumab in patients undergoing cancer therapy.

Bone marrow osteoblast vulnerability to chemotherapy

Osteoblasts are a major component of the bone marrow microenvironment, which provide support for hematopoietic cell development. Functional disruption of any element of the bone marrow niche, including osteoblasts, can potentially impair hematopoiesis. We have studied the effect of two widely used drugs with different mechanisms of action, etoposide (VP16) and melphalan, on murine osteoblasts at distinct stages of maturation. VP16 and melphalan delayed maturation of preosteoblasts and altered CXCL12 protein levels, a key regulator of hematopoietic cell homing to the bone marrow. Sublethal concentrations of VP16 and melphalan also decreased the levels of several transcripts which contribute to the composition of the extracellular matrix (ECM) including osteopontin (OPN), osteocalcin (OCN), and collagen 1A1 (Col1a1). The impact of chemotherapy on message and protein levels for some targets was not always aligned, suggesting differential responses at the transcription and translation or protein stability levels. As one of the main functions of a mature osteoblast is to synthesize ECM of a defined composition, disruption of the ratio of its components may be one mechanism by which chemotherapy affects the ability of osteoblasts to support hematopoietic recovery coincident with altered marrow architecture. Collectively, these observations suggest that the osteoblast compartment of the marrow hematopoietic niche is vulnerable to functional dysregulation by damage imposed by agents frequently used in clinical settings. Understanding the mechanistic underpinning of chemotherapy-induced changes on the hematopoietic support capacity of the marrow microenvironment may contribute to improved strategies to optimize patient recovery post-transplantation.

Bone disease in organ transplant patients: pathogenesis and management

Bone disease is common in recipients of kidney, heart, lung, liver, and bone marrow transplants, and causes debilitating complications, such as osteoporosis, osteonecrosis, bone pain, and fractures. The frequency of fractures ranges from 6% to 45% for kidney transplant recipients to 22% to 42% for heart, lung, and liver transplant recipients. Bone disease in transplant patients is the sum of complex mechanisms that involve both preexisting bone disease before transplant and post-transplant bone loss due to the effects of immunosuppressive medications. Evaluation of bone disease should preferably start before the transplant or in the early post-transplant period and include assessment of bone mineral density and other metabolic factors that influence bone health. This requires close coordination between the primary care physician and transplant team. Patients should be stratified based on their fracture risk. Prevention and treatment include risk factor reduction, antiresorptive medications, such as bisphosphonates and calcitonin, calcitriol, and/or gonadal hormone replacement. A steroid-avoidance protocol may be considered.

Bone marrow osteoblast damage by chemotherapeutic agents

Hematopoietic reconstitution, following bone marrow or stem cell transplantation, requires a microenvironment niche capable of supporting both immature progenitors and stem cells with the capacity to differentiate and expand. Osteoblasts comprise one important component of this niche. We determined that treatment of human primary osteoblasts (HOB) with melphalan or VP-16 resulted in increased phospho-Smad2, consistent with increased TGF-β1 activity. This increase was coincident with reduced HOB capacity to support immature B lineage cell chemotaxis and adherence. The supportive deficit was not limited to committed progenitor cells, as human embryonic stem cells (hESC) or human CD34+ bone marrow cells co-cultured with HOB pre-exposed to melphalan, VP-16 or rTGF-β1 had profiles distinct from the same populations co-cultured with untreated HOB. Functional support deficits were downstream of changes in HOB gene expression profiles following chemotherapy exposure. Melphalan and VP-16 induced damage of HOB suggests vulnerability of this critical niche to therapeutic agents frequently utilized in pre-transplant regimens and suggests that dose escalated chemotherapy may contribute to post-transplantation hematopoietic deficits by damaging structural components of this supportive niche.

NCI, NHLBI/PBMTC first international conference on late effects after pediatric hematopoietic cell transplantation: endocrine challenges-thyroid dysfunction, growth impairment, bone health, & reproductive risks

The endocrine system is highly susceptible to damage by high-dose chemotherapy and/or irradiation before hematopoietic cell transplantation (HCT) during childhood. The specific endocrine organs most affected by HCT include the thyroid gland, the pituitary, and the gonads. In addition, hormones that support development and stability of the skeletal system are also affected. Insufficiency of thyroid hormone is 1 of the most common late sequelae of HCT, and occurs more often in young children. Deficiency in the pituitary's production of growth hormone is a problem of unique concern to the pediatric population. The reproductive risks of HCT depend on the patient's gender and pubertal status at the time of HCT. Pubertal or gonadal failure frequently occurs, especially in females. Infertility risks for both genders remain high, whereas methods of fertility preservation are limited in all but postpubertal males. Bone health post-HCT can be compromised by low bone mineral density as well as avascular necrosis, but the data on both problems in the pediatric HCT population are limited. In this paper, the current state of knowledge, gaps in that knowledge, and recommendations for future research are addressed in detail for each of these systems.

Common genetic variants are associated with accelerated bone mineral density loss after hematopoietic cell transplantation

Background

Bone mineral density (BMD) loss commonly occurs after hematopoietic cell transplantation (HCT). Hypothesizing that genetic variants may influence post-HCT BMD loss, we conducted a prospective study to examine the associations of single nucleotide polymorphisms (SNP) in bone metabolism pathways and acute BMD loss after HCT.

Methods and Findings

We genotyped 122 SNPs in 45 genes in bone metabolism pathways among 121 autologous and allogeneic HCT patients. BMD changes from pre-HCT to day +100 post-HCT were analyzed in relation to these SNPs in linear regression models. After controlling for clinical risk factors, we identified 16 SNPs associated with spinal or femoral BMD loss following HCT, three of which have been previously implicated in genome-wide association studies of bone phenotypes, including rs2075555 in COL1A1, rs9594738 in RANKL, and rs4870044 in ESR1. When multiple SNPs were considered simultaneously, they explained 5–35% of the variance in post-HCT BMD loss. There was a significant trend between the number of risk alleles and the magnitude of BMD loss, with patients carrying the most risk alleles having the greatest loss.

Conclusion

Our data provide the first evidence that common genetic variants play an important role in BMD loss among HCT patients similar to age-related BMD loss in the general population. This infers that the mechanism for post-HCT bone loss is a normal aging process that is accelerated during HCT. A limitation of our study comes from its small patient population; hence future larger studies are warranted to validate our findings.

Bone mineral density in adult survivors of childhood acute leukemia: impact of hematopoietic stem cell transplantation and other treatment modalities

Femoral and lumbar bone mineral densities (BMDs) were measured in 159 adults enrolled in the Leucémies de l'Enfant et de l'Adolescent program, a French prospective multicentric cohort of childhood leukemia survivors. BMDs were expressed as Z-scores, and multivariate linear regression analyses were used to construct association models with potential risk factors. Mean age at evaluation and follow-up was 23 and 14.7 years, respectively. In the whole cohort, mean femoral Z-score was -0.19 ± 0.08. Two factors were associated with lower femoral BMD transplantation (-0.49 ± 0.15 vs -0.04 ± 0.10 in the chemotherapy group; P = .006) and female sex (-0.34 ± 0.10 vs -0.03 ± 0.13; P = .03). Among patients who received a transplant, the only significant risk factor was hypogonadism (-0.88 ± 0.16 vs -0.10 ± 0.23; P = .04). A slight reduction in lumbar BMD (mean Z-score, -0.37 ± 0.08) was detected in the whole cohort without difference between the transplantation and chemotherapy groups. Among patients who received a transplant, younger age at transplantation was correlated with a low lumbar BMD (P = .03). We conclude that adults who had received only chemotherapy for childhood leukemia have a slight reduction in their lumbar BMD and a normal femoral BMD. Patients who received a transplant with gonadal deficiency have a reduced femoral BMD which might increase the fracture risk later in life.

Natural history of potential celiac disease in children

BACKGROUND & AIMS

The presence of celiac disease-associated autoantibodies (antiendomysium and antitissue transglutaminase [anti-TG2]) with normal jejunal mucosa indicate potential celiac disease. We performed a prospective, 3-year cohort study to determine the natural history of potential celiac disease in children.

METHODS

The study included 106 children with potential celiac disease, based on serology analysis and normal duodenal architecture. All but 2 carried the HLA-DQ2 and/or DQ8 haplotype. In all children, every 6 months, growth, nutritional parameters, celiac disease serology, and autoimmunity were investigated. In biopsies, γδ intraepithelial-, CD3-, and lamina propria CD25-positive cells were counted; duodenal deposits of anti-TG2 immunoglobulin A were detected. Biopsy analysis was repeated after 2 years on patients with persistent positive serology and/or symptoms.

RESULTS

Celiac disease was detected primarily in first-degree relatives and patients with autoimmune disorders (40.6%). A gluten-free diet was prescribed to 20/106 patients because of symptoms, which were relieved in only 11. Eighty-nine of the 106 patients entered the follow-up study, with normal daily consumption of gluten. During the follow-up antibodies disappeared in 14.6% and fluctuated in 32.6%. Villous atrophy was observed in 12/39 patients (30.8%) who underwent a repeat biopsy.

CONCLUSIONS

Most children with potential celiac disease remain healthy. After 3 years, approximately 33% of patients develop villous atrophy. Intestinal deposits of anti-TG2 IgA identify children at risk for villous atrophy.

p21cip/WAF is a key regulator of long-term radiation damage in mesenchyme-derived tissues

This study aimed to determine the mechanisms responsible for long-term tissue damage following radiation injury. We irradiated p21-knockout (p21(-/-)) and wild-type (WT) mice and determined the long-term deleterious effects of this intervention on mesenchyme-derived tissues. In addition, we explored the mechanisms of radiation-induced mesenchymal stem cell (MSC) dysfunction in isolated bone marrow-derived cells. p21 expression was chronically elevated >200-fold in irradiated tissues. Loss of p21 function resulted in a >4-fold increase in the number of skin MSCs remaining after radiation. p21(-/-) mice had significantly less radiation damage, including 6-fold less scarring, 40% increased growth potential, and 4-fold more hypertrophic chondrocytes in the epiphyseal plate (P<0.01). Irradiated p21(-/-) MSCs had 4-fold increased potential for bone or fat differentiation, 4-fold greater proliferation rate, and nearly 7-fold lower senescence as compared to WT MSCs (P<0.01). Ectopic expression of p21 in knockout cells decreased proliferation and differentiation potential and recapitulated the WT phenotype. Loss of p21 function markedly decreases the deleterious effects of radiation injury in mesenchyme-derived tissues and preserves tissue-derived MSCs. In addition, p21 is a critical regulator of MSC proliferation, differentiation, and senescence both at baseline and in response to radiation.

NanoLC-MS/MS analyses of urinary desmosine, hydroxylysylpyridinoline and lysylpyridinoline as biomarkers for chronic graft-versus-host disease

Chronic graft-versus-host disease (cGVHD) is a common and potentially lethal complication of allogeneic hematopoietic stem cell transplantation (HSCT). cGVHD as well as the transplant procedure itself (chemotherapy with or without radiotherapy) can lead to the degradation of connective tissue components such as elastin and collagen. The catabolism of these structural proteins releases desmosine (DES), lysylpyridinoline (LP), hydroxylysylpyridonoline (HP), and related pyridinium-based cross-linkers analogues that could represent potential biomarkers for cGVHD. This study reports the development of a sensitive liquid chromatography/tandem mass spectrometry method for the simultaneous analysis of N-propyl derivatives of DES, HP, and LP. The concentrations of free and total forms of urinary DES, HP, and LP were determined using synthetic deuterated internal standards. This method enabled accurate quantitation of these pyridinium-based cross-linkers from as little as 100 microL of urine with detection limits of 0.03-0.10 ng/mL. These compounds were analyzed in urine samples from three groups of patients: (1) Healthy volunteers, (2) Autologous HSCT recipients (who cannot develop cGVHD), and (3) Allogeneic HSCT recipients at onset of cGHVD. These analyses revealed that the urinary concentrations of DES, HP, and LP in the autologous recipients were greater or equal to the cGVHD group although both groups showed marked increase in the levels of these compounds compared to healthy individuals. These results suggest that the chemotherapy treatment has significant effects on the turnover of elastin and collagen, and that these biomarkers could be effective during prospective analyses to determine the onset of cGVHD.

Bone involvement in clusters of autoimmune diseases: just a complication?

Bone loss, described in individual groups of patients with Type 1 diabetes (T1D), autoimmune thyroid disease (ATD) or celiac disease (CD) is usually viewed as a complication of these diseases. There is increasing evidence that alterations in the immune system may directly affect bone mass. Clustering of autoimmune diseases in the same individual might predispose to higher risk of osteopenia due to imbalance in immune regulation. The aim of this study was to evaluate bone involvement in clusters of the most common autoimmune diseases (T1D, ATD and CD) in children. The study was performed at a tertiary care center for the care of pediatric diabetes. One-hundred-two patients with T1D alone or associated with ATD and/or CD were studied; 13 patients had cluster of three autoimmune diseases. Amplitude-dependent speed of sound (AD-SoS) was measured by phalangeal quantitative ultrasound and expressed as standard deviation score (SDS). AD-SoS SDS < -2 was considered indicative of osteopenia. Osteopenia was equally distributed among children with T1D alone (8.1%), T1D associated with ATD (7.7%) or CD (10.3%), while it was 53.8% in patients presenting with three autoimmune diseases. Poor compliance to gluten-free diet increased osteopenia to 18.8% in patients with T1D and CD and 80% in patients with three autoimmune disorders. No difference among groups was found with regard to gluco-metabolic control, calcium metabolism, thyroid function. In conclusion bone impairment in multiple autoimmune diseases might be considered not only a complication due to endocrine or nutritional mechanisms, but also a consequence of an immunoregulatory imbalance. Alterations of homeostatic mechanisms might explain an imbalance of osteoclast activity leading to osteopenia.

Pilot study on the use of zoledronic acid to prevent bone loss in allo-SCT recipients

Bone loss is recognized as worsening the quality of life in long-term survivors of Allo-SCT. This study evaluated the risk factors associated with bone loss and the role of zoledronic acid in preventing bone loss in allogeneic recipients. Fifty-three patients who underwent HLA-matched Allo-SCT were evaluated for their bone mineral density (BMD) in the lumbar spine and femoral neck at regular intervals. Zoledronic acid (4 mg) was given i.v. to 18 patients (ZA patients) at 2 months after SCT and then every 3 months until 2 years. Grade 2-4 acute GVHD was associated with bone loss (odds ratio (OR)=4.90, 95% confidence interval (CI)=1.41-16.99; P=0.012) at 1 year after SCT, whereas extensive chronic GVHD and steroid use were both unfavorable prognostic factors (OR=9.00 and 7.22, 95% CI=1.52-53.40 and 1.44-36.22; P=0.016, respectively) in terms of osteopenia/osteoporosis at 2 years after transplantation. The use of zoledronic acid significantly prevented bone loss in the femoral neck as well as the spine (OR=0.18, 95% CI=0.05-0.69, P=0.012). Therefore, BMD measurements and the use of zoledronic acid are recommended in cases of GVHD or long-term steroid use after Allo-SCT to prevent bone loss and threatening skeletal events.

The influence of gluten free diet on quantitative ultrasound of proximal phalanxes in children and adolescents with type 1 diabetes mellitus and celiac disease

A reduced bone mineral density has been reported in patients with untreated celiac disease (CD) as well as in patients with poorly controlled type 1 diabetes mellitus (T1DM). The aim of this study was to evaluate the bone mineral status by phalangeal quantitative ultrasound in 52 children and adolescents with both diseases (mean age 13.3+/-4.9 years). As a control group 50 patients with T1DM and no CD (age 12.2+/-4.0 years) were studied. The following bone parameters, amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT) were considered and expressed as z score. Compliance to gluten free diet and long term glycemic control (mean of four determinations of HbA1c in the last year) were also assessed. The lowest mean AD-SoS z score values were found in patients with T1DM and CD, who reported transgressions to gluten free diet and exhibited positivity for serum anti-tissue transglutaminase antibodies (tTG) and/or endomysial antibodies (EmA), compared with patients with occasional transgressions but negative for anti-tTG and/or -EmA, patients strictly adherent to the diet, and patients who suffered only from diabetes (ANOVA p=0.021). No difference was found between patients with diabetes alone and patients with both diseases strictly adherent to gluten free diet. Prevalence of osteopenia (z AD-SoS values <-2 SD) was higher in patients with T1DM and CD and poor compliance to the diet (45.5%) compared with patients with T1DM (8%) or patients with both diseases strictly compliant to diet (12.9%) (p=0.015). A negative correlation between Ad-SoS z score and HbA1c (r -0.236, p=0.036) was found when patients with T1DM and patients with T1DM and CD, who strictly adhere to the diet, were pooled. In conclusion the quality of bone as assessed by phalangeal ultrasound in patients with T1DM and CD, who strictly adhere to gluten free diet, is similar to that found in T1DM patients. A higher prevalence of osteopenia is present in patients with both diseases who reported habitual transgressions to gluten free diet. The gluten free diet, as well as the optimization of glycemic control, plays an important role in preventing the osteopenic status caused by the clustering of these two chronic diseases.

Bone loss and its management in long-term survivors from allogeneic stem cell transplantation

CONTEXT

Recently, great efforts have been made to understand the pathogenesis of bone loss after allogeneic stem cell transplant (allo-SCT) and possible treatments.

EVIDENCE ACQUISITION

A literature search of the MEDLINE database was performed to find articles in English using the search terms "allogeneic stem cell transplant" or "bone marrow transplant," in combination with "bone loss," "osteoporosis treatment," "osteoblast," "cytokines," or "osteoprotegerin." Reference lists from the articles retrieved were also evaluated for relevant information.

EVIDENCE SYNTHESIS

Bone mineral density at the lumbar spine, but not at the femur, can improve or even recover several years after SCT. Multiple risk factors for posttransplant bone loss have been recently identified: abnormalities in the immune system function and their treatments, reduced production of growth factors, osteoclast activation by increased cytokine release, and decreased number and function of osteoblast precursors within the stromal stem cell compartment. Pamidronate was partially successful in preventing posttransplant bone loss, whereas both oral and parenteral bisphosphonates had beneficial effects on documented osteoporosis in long-term survivors.

CONCLUSIONS

There is clear evidence that transplant-related bone loss is a multifactorial, early, and possibly long-lasting disorder. All patients who have already received allo-SCT should be evaluated as to their bone status and treated with appropriate supportive measures and specific treatments as soon as abnormalities are detected. Although preventive antiresorptive treatments are only partially effective, they should be started in all patients before or at the time of allo-SCT, regardless of their bone mineral density values, and continued at least for the first year after transplant.

Post-transplantation osteoporosis

Osteoporosis is prevalent in transplant recipients and is related to pre- and post-transplantation factors. Low bone density and fractures may antedate transplantation, related to traditional risk factors for osteoporosis, effects of chronic illness, and end-stage organ failure and its therapy, on the skeleton. Bone loss after transplantation is related to adverse effects of immunosuppressive drugs (glucocorticoids and calcineurin inhibitors) on bone remodeling. Newer immunosuppressive medications may permit lower doses of glucocorticoids and may be associated with decreased bone loss and fractures. Bisphosphonates are currently the most effective agents for the prevention and treatment of post-transplantation osteoporosis.

High prevalence of early-onset osteopenia/osteoporosis after allogeneic stem cell transplantation and improvement after bisphosphonate therapy

Osteopenia/osteoporosis (O/O) has been associated with allogeneic stem cell transplantation (alloSCT). We retrospectively reviewed 102 patients undergoing a first alloSCT from 2000 to 2005 at our center to evaluate the prevalence of O/O < or =6 and >6 months post-alloSCT. Fifty-six patients did not have a dual energy X-ray absorptiometry (DXA) scan following alloSCT. Approximately half (n=13/27) of those with a first DXA scan < or =6 months post-alloSCT had O/O and a similar rate (n=9/19) was seen in those with a first DXA scan >6 months. There were no significant differences in patient characteristics between the normal and O/O groups. The dual femur (DF) appeared to be more vulnerable to alloSCT-induced bone mineral density (BMD) loss than the lumbar spine (LS), regardless of screening time. O/O patients were treated with bisphosphonates and 41% had a repeat DXA scan post-treatment. No patient developed jaw osteonecrosis and significant BMD improvement was seen at the LS (mean BMD, 1.03+/-0.13 vs 1.08+/-0.12, P=0.004) but not the DF (mean BMD, 0.84+/-0.06 vs 0.85+/-0.08, P=0.29), indicating BMD loss at the DF is more resistant than the LS to antiresorptive therapy. Our results demonstrate that O/O is an early and late complication post-alloSCT and bisphosphonate treatment reverses BMD loss at the LS.

Loss of bone mineral density and secondary hyperparathyroidism are complications of autologous stem cell transplantation

Patients who underwent autologous stem cell transplantation (ASCT) are prone to decreased bone mineral density (BMD). We measured BMD in 180 patients who underwent ASCT for hematologic malignancies. Patients were evaluated with a median of 6.2 years after ASCT. Twenty patients who received only chemotherapy were evaluated as controls. The loss of bone mass was greater during the first year after ASCT, since majority of patients recover BMD and normalize bone turnover markers during the following years. After ASCT, over half of the patients show osteopenia or osteoporosis independent of the sex. According to the results of other groups, our results emphasize the potential usefulness of antiresorptive agents to prevent or treat post-ASCT osteopenia or osteoporosis, and the importance of the measurement of BMD as an integral component to the follow-up of ASCT.

Estrogen-progestin therapy in women after stem cell transplant: our experience and literature review

Women undergoing stem cell transplantation (SCT) are mostly young and have more than 90% probability of ovarian failure, which is often permanent. A woman's age, use of radiotherapy and alkylating chemotherapy, and the allogeneic type of transplant are associated with a higher rate of premature ovarian failure and worse residual ovarian function. Premature ovarian failure has serious systemic and psychological effects that may need treatment and should be managed by practitioners trained to treat this particular population of women. Ultrasonographic evidence of ovarian follicles is often associated with a future resumption of cycles, but there are no serum markers to predict the return of ovarian function in these patients. In our center, the rate of ovarian function recovery was 7% after allogeneic SCT and 25% after autologous SCT (P<0.05). There are no guidelines on how to manage premature ovarian failure induced by myeloablative treatments followed by SCT. Because of the likelihood of the need for long-lasting estrogen plus progestin therapy (EPT) and the increased risk of secondary neoplasia after SCT, the EPT should be as physiological as possible. In our experience, the cyclical sequential combination of estradiol (2 mg daily) plus dydrogesterone (10 mg for 14 d/mo) was associated with excellent compliance because of its simple administration and few adverse effects. Such a treatment led to a dramatic improvement in vasomotor, urogenital, and psychological symptoms related to estrogen deficiency. However, in the allogeneic transplantation setting, up to 25% of women may suffer from gynecological chronic graft-versus-host disease, which may become apparent as hematocolpometra after introduction of EPT. Thus, accurate pretreatment evaluation and frequent monitoring during treatment are required. Moreover, EPT absorption may be reduced in patients who received allotransplants and have gastrointestinal or skin chronic graft-versus-host disease.

The effects of various irradiation doses on the growth and differentiation of marrow-derived human mesenchymal stromal cells

Mesenchymal stromal cells (MSC) are progenitors of mesenchymal tissues including bones. Irradiation can damage the osteogenic activity of human marrow by suppressing osteoblasts leading to post-irradiation osteoporosis. However, the effect of therapeutic irradiation on MSC remains unexplored. We investigated the effects of various doses of X-ray irradiation on human MSC (hMSC) by measuring its post-irradiation proliferation and differentiation activities. Standard immunophenotypes and differentiating functions of the MSC were determined. Irradiation inhibited proliferation of hMSC up to two wk post-irradiation but thereafter, those residual surviving cells regained their normal proliferation rate. Bone forming activity as reflected by alkaline phosphatase (ALP) and calcium deposition were both reduced in a dose-dependent fashion. Maximum suppressive effect on osteogenic activity was noted in MSC treated with high-dose irradiation (12 Gy). Adipocyte percentage was also reduced by 50% in cultures that received >4 Gy. Attempts to protect the irradiated cells with 1 microM all-trans retinoic acid did not show any beneficial effect on MSC proliferation and differentiation. The direct impairment of proliferation and osteogenic differentiation potential of MSC by irradiation may contribute partly to the post-transplant osteoporosis.

Imbalance of the Osteoprotegerin/RANKL Ratio in Bone Marrow Microenvironment After Allogeneic Hemopoietic Stem Cell Transplantation

BACKGROUND

Bone loss is a common complication after allogeneic stem cell transplantation. Osteoprotegerin (OPG) plays a critical role in bone remodeling by neutralizing the effect of receptor activator of nuclear factor-kappaB ligand (RANKL) on differentiation and activation of osteoclasts. We investigated OPG and RANKL in serum and marrow plasma in transplanted patients.

MATERIALS AND METHODS

In 36 patients and 36 controls, the relationships among bone mineral density, circulating OPG, RANKL, interferon-gamma, and interleukin-6 levels were investigated; in addition, OPG and RANKL were measured in marrow plasma and in conditioned medium of long-term cultures of marrow mesenchymal-derived osteogenic cells.

RESULTS

Lumbar and femoral bone mineral density were lower in patients than in controls (P<0.01). Serum OPG (sOPG) and interferon-gamma were significantly higher in patients than in controls (P<0.05). Patients' interferon-gamma correlated with sOPG levels (r=0.4; P=0.03). Interleukin-6 did not differ between patients and controls. By contrast, OPG levels were lower in patients than in controls in marrow plasma (P<0.001) and in conditioned media after one (P=0.035) and three months (P=0.003) of culture of marrow mesenchymal-derived osteogenic cells. RANKL was similar in patients and controls. The OPG/RANKL ratio "in situ" was significantly lower in patients than in controls (P<0.05). There was no correlation between sOPG and marrow OPG, RANKL levels, densitometric values, and chronic graft-versus-host disease.

CONCLUSION

Our findings suggest that after allogeneic stem cell transplantation: 1) sOPG bear no relationship with OPG in the bone marrow; 2) increased sOPG can be the result of its enhanced production in extra bone tissues triggered by inflammatory cytokines; 3) low bone marrow OPG levels may be partly related to the persistent quantitative and qualitative deficit of osteoblastic precursors; and 4) reduced OPG/RANKL ratio in bone microenvironment may increase bone remodeling by promoting bone resorption.

Effects of various antireabsorptive treatments on bone mineral density in hypogonadal young women after allogeneic stem cell transplantation

Ovarian failure after allogeneic stem cell transplant (allo-SCT) is an important risk factor for development of osteoporosis. We investigated the effects of various antiresorptive treatments in long-term surviving females with ovarian failure after allo-SCT. A total of 60 women with osteoporosis or osteopenia were divided randomly into four groups of 15 women each. Group 1 was treated with calcium and vitamin D alone, group 2 received the same treatment in combination with hormone replacement therapy (HRT), group 3 received risedronate (35 mg weekly, orally for 1 year) and group 4 zoledronic acid (3 monthly doses of 4 mg (intravenous)). All groups were similar for age, body mass index, underlying disease and time elapsed from transplant. Lumbar and femoral bone mineral density (BMD) were measured at baseline and after 12 months, together with serum osteocalcin and urinary hydroxyproline. At 12 months, a significant decrease in lumbar and femoral BMD was observed in group 1 and a milder decrease in group 2. Risedronate treatment increased significantly lumbar BMD and prevented bone loss at the femoral neck. Zoledronic acid increased significantly both lumbar and femoral BMD. In groups 3 and 4 the hydroxyproline excretion was significantly reduced, while osteocalcin mildly increased only in group 4. In conclusion, bisphosphonate administration is useful to prevent and treat bone demineralization in young adult women after allo-SCT.

Late effects of hematopoietic cell transplantation among 10-year adult survivors compared with case-matched controls

PURPOSE

To determine late effects of hematopoietic cell transplantation (HCT) on health problems and health-related quality of life for 10-year survivors.

PATIENTS AND METHODS

Four hundred five adults consented to the study before HCT. Medical records and standardized self-report measures were maintained prospectively. After 10 years, 137 survivors and nontransplant controls, case-matched on age, sex, and race, completed self-report of medical problems, symptoms, and health-related quality of life.

RESULTS

Survivors and controls had similar rates of hospitalization and most diseases, but survivors reported an average of 3.5 medical problems versus 1.7 for controls (P < .001). Survivors reported more musculoskeletal stiffness, cramps, weakness and joint swelling (P < .001), cataract surgery (P < .001), hepatitis C (P = .004), sexual problems for men (P = .01) and women (P < .001), restrictions in social function (P = .002), memory and attention concerns (P = .003), urinary frequency or leaking (P = .006), use of psychotropic medication (P = .009), and denial of life and health insurance (P < .001). Survivors and controls did not differ in self-reported rates of osteoporosis, hypothyroidism, employment, marital satisfaction, divorce, or psychological health.

CONCLUSION

Although indistinguishable in many respects, survivors had more medical needs than controls. Health problems were not focused on specific diseases or limited to survivors with readily identifiable risk factors. Musculoskeletal problems require both screening and research into etiologies and effective treatments. Osteoporosis and hypothyroidism may be underdiagnosed. Survivors require screening for sexual problems, urinary frequency, mood and need for antidepressants or benzodiazepines.

Defective stromal cell function in a mouse model of infusion-induced bone marrow failure

OBJECTIVE

To study bone marrow (BM) stromal damage in a mouse model of infusion-induced BM failure.

MATERIALS AND METHODS

Sublethally irradiated CByB6F1 mice were infused with 5 x 10(6) C57BL/6 (B6) lymph node (LN) cells. Recipient BM cells were taken at 3, 7, 10, and 14 days following LN infusion and were cultured in vitro in alpha-modified Eagle media for 2-3 weeks. Peripheral blood and was analyzed by complete blood counts while BM lymphocyte infiltration/expansion was analyzed by flow cytometry. Marrow cells from affected and control mice were mixed and cultured in vitro to test nonspecific stromal damage.

RESULTS

Donor lymphocytes infiltrated host BM within 3-7 days and expanded significantly between 7 and 10 days, concurrent with the development of leukopenia, thrombocytopenia, and marrow hypoplasia. BM cells from mice at 7, 10, and 14 days after B6-LN cell infusion were progressively defective in forming stromal feeder layers. A 1:1 mixture of BM cells from affected CByB6F1 mice and normal B6 mice failed to form an effective stromal feeder layer that could support cobblestone colony formation, indicating that lymphocytes in the BM of affected CByB6F1 mice were able to damage stromal cells in the normal B6 BM.

CONCLUSION

Activated lymphocytes destroy both hematopoietic and stromal cells as innocent bystanders in the infusion-induced BM failure model.

Posttransplant hematopoiesis in patients undergoing sibling allogeneic stem cell transplantation reflects that of their respective donors although with a lower functional capability

We tested the principle of whether patient long-term hematopoiesis following allogeneic stem cell transplantation (allo-SCT) reflects the characteristics of the hematopoiesis of their respective donor. For this purpose, we analyzed bone marrow (BM) hematopoiesis using long-term cultures (LTC), delta assays, and clonogeneic assays as well as CD34+ cells and their subsets by flow cytometry in a series of 37 patients undergoing allo-SCT, and we compared it to that of their respective human leukocyte antigen-matched sibling donors in a paired study performed more than 1 year after the transplant procedure. Interestingly, the main factor that influenced post-allo-SCT BM hematopoiesis in the long term was donor hematopoiesis. Nevertheless, compared to their respective donors, patients exhibited a significantly lower number of colony-forming units granulomonocytic, burst-forming units erythroid, and immature progenitors (CD34++/CD38dim/CD90+/CD133+ cells, LTC-initiating cells, and colonies generated in the delta assay). Moreover, BM stromal function was diminished in patients undergoing allo-SCT compared to their donors. In addition, the presence of chronic graft-versus-host disease under immunosuppressive treatment also conditioned an impaired hematopoietic function. In summary, our study shows that BM hematopoiesis evaluated more than 1 year after an allo-SCT mainly reproduces that of their respective donors, although with a significantly decreased in vitro activity.

Promises and pitfalls of stem cell therapy for promotion of bone healing

There is promise in combining stem cells with allogeneic bone matrix to promote bone healing. Murine bone marrow, peripheral blood, and compact bone cells were transplanted ectopically under the kidney capsule in mice, alone or in combination with allogeneic matrix products: powder and putty to determine their bone forming potential in comparison to transplanted femoral bone fragments and long-term cultured bone marrow cells. The end point was the amount of bone formed as determined by quantitative histology. Mononuclear cells from marrow, peripheral blood, or bone alone transplanted under the kidney capsule did not form bone. Mononuclear cell populations did not combine readily with matrix products and there was in vivo migration of the transplanted combinations. Kidney subcapsular transplanted cultured bone marrow cells formed bone in proportion to the culture period, but after 9 weeks, the extent was only 20% by area of that of similarly transplanted femoral bone fragments. An inductive stimulus for bone formation seemed necessary. Osteoprogenitor cells were not detected in significant numbers in blood unless high doses of cytokines were administered. A better definition of the optimal cell populations and manipulations required for promotion of bone healing is needed along with new (transplant) models that allow for cell tracking. Much work remains to overcome current pitfalls in the use of stem cells to promote allograft integration and bone healing.

LEVEL OF EVIDENCE

Therapeutic study, Level V (expert opinion). See the Guidelines for Authors for a complete description of levels of evidence.

Short-term zoledronic acid treatment increases bone mineral density and marrow clonogenic fibroblast progenitors after allogeneic stem cell transplantation

Although osteoporosis is a relatively common complication after allogeneic stem cell transplantation, the role of bisphosphonates in its management has not yet been completely established. Thirty-two patients who underwent allogeneic stem cell transplantation were prospectively evaluated for bone mineral density (BMD) at the lumbar spine (LS) and femoral neck (FN) after a median period of 12.2 months. Then, 15 of the patients with osteoporosis or rapidly progressing osteopenia (bone loss > 5%/yr) received three monthly doses of 4 mg zoledronic acid iv. Fifteen patients were followed up without treatment, and all 30 patients were reevaluated after 12 months for BMD and bone turnover markers. By using enriched mesenchymal stem cells in the colony-forming units fibroblast (CFU-F) assay, we evaluated the osteogenic stromal lineage. This procedure was performed in both groups of patients at study entry and after 12 months. The average BMD loss was 3.42% at LS and 3.8% at FN during a 1-yr longitudinal evaluation in 32 patients. Subsequently, BMD increased at both LS and FN (9.8 and 6.4%, respectively) in the zoledronic acid-treated cohort. Hydroxyproline excretion decreased, and serum bone-specific alkaline phosphatase increased significantly, whereas serum osteocalcin increase did not reach the limit of significance. A significant increase in CFU-F growth in vitro was induced by in vivo zoledronic acid administration. In the untreated group, no significant change was observed in bone turnover markers, LS BMD (-2.1%), FN BMD (-2.3%), and CFU-F colony number. In conclusion, short-term zoledronic acid treatment consistently improved both LS and FN BMD in transplanted patients who were at high risk for fast and/or persistent bone loss, partly by increasing the osteogenic progenitors in the stromal cell compartment.

Avascular Osteonecrosis After Allogeneic Hematopoietic Stem-Cell Transplantation: Diagnosis and Gender Matter

BACKGROUND

Avascular osteonecrosis (AVN) is a serious complication of allogeneic stem-cell transplantation (SCT). Acute and chronic graft-versus-host disease and its treatment with steroids are identified as main risk factors. In a single-center, prospective cohort study of patients undergoing allogeneic SCT for chronic myeloid leukemia (CML), acute myeloid leukemia, myelodysplastic syndrome, and acute lymphatic leukemia, we determined the incidence of hip AVN necessitating total arthroplasty (severe adverse event) and performed risk factor analysis.

METHODS

A total of 255 patients were followed for an observation period of at least 4 years. Thirteen potential risk factors including age, recipient and donor gender, underlying disease and disease stage, conditioning therapy, human leukocyte antigen match, acute or chronic graft-versus-host disease, and immunosuppressive medication were tested in univariate and multifactorial nominal logistic and Cox proportional hazard analyses.

RESULTS

Severe adverse events occurred in eight patients (4-year cumulative incidence rate 6.1%). Univariate and multifactorial analysis revealed a diagnosis other than CML and steroid intake as main risk factors (chi model 31.6, P=0.0005; chi diagnosis 11, P=0.001; chi steroid 6.8, P=0.009). The demonstrably strong influence of diagnosis was steroid independent (steroid intake in CML comparable to non-CML). We repeated the analysis in 103 patients without CML (70 with acute myeloid leukemia, 13 with myelodysplastic syndrome, and 20 with acute lymphatic leukemia), excluding 152 patients with CML. Univariate and multifactorial analyses revealed female gender (of both recipient and donor) as risk factors for AVN in addition to steroids. Relative AVN risk for female compared with male donor transplantation was 8.7 (P=0.01); relative AVN risk for female compared with male recipient transplantation was 4.3 (P=0.047).

CONCLUSIONS

Diagnosis and gender are steroid-independent risk factors for severe hip AVN after allogeneic SCT.

Quantitative ultrasound of proximal phalanxes in patients with type 1 diabetes mellitus

The influence of duration of diabetes and metabolic control on phalangeal quantitative ultrasound (QUS) was evaluated in a group of children and adolescents with type 1 diabetes. Eighty-six patients (mean age 11.9 years; mean duration 4.3 years) were studied. Daily calcium intake was assessed by means of a questionnaire. Amplitude-dependent speed of sound (AD-SoS) was measured at the phalanxes of the non-dominant hand and expressed as a z-score. Linear and multivariate correlations with duration of diabetes and, short term and long term metabolic control were sought. AD-SoS z-score was -0.43+/-1.4 (95% CI, -0.73; -0.13). Nine subjects had values below -2S.D. Daily calcium intake was 1042+/-456 mg/day; 47 subjects (54.6%) were below the recommended levels. A negative correlation was found between AD-SoS z-score and duration (r, -0.33, P=0.002) or metabolic control (HbA1c-last year r, -0.32, P=0.002; HbA1c-whole duration, r, -0.40; P=0.003). Negative AD-SoS z-scores depended significantly and directly on duration and quality of metabolic control, even when controlled for calcium intake. In conclusion, the architectural organization of bone was impaired in 10.5% patients. Duration of diabetes and poor metabolic control were the main determinants affecting AD-SoS. QUS may be a useful tool in the screening of bone disturbance in young patients with diabetes. Optimization of metabolic control is required to prevent osteoporosis.

Strategic approaches to osteoporosis in transplantation

Recipients of stem cell transplantation are at risk for osteopenia and osteoporosis. Longitudinal studies performed in adults have shown that significant bone demineralization occurs following myeloablative therapy and subsequent immune suppression. Among children and adolescents, cross-sectional analyses indicate that younger patients are also at risk for long-term bone toxicity. Strategies to detect and manage this disorder in pediatric SCT recipients are presented.

Beneficial treatment with risedronate in long-term survivors after allogeneic stem cell transplantation for hematological malignancies

In this prospective randomized study we evaluated the effect of risedronate, an aminobisphosphonate, on bone mass and turnover in patients who had undergone allogeneic stem cell transplant (SCT) for hematological malignancies. Thirty-four patients (18 females, 16 males, age 32+/-10 years) with bone mineral density (BMD) </=-1.5 SD as a T-score at least 6 months after SCT were treated with calcium 1 g/day and vitamin D 800 IU/day and randomized to receive ( n=17, group 1) or not receive ( n=17, group 2) oral risedronate 5 mg/day. The duration of treatment was 12 months. After 6 months, lumbar BMD increased by 4.4+/-1.6% in patients of group 1 and decreased by 4.3+/-1.5% in those of group 2 ( P<0.05); at the femoral neck, BMD did not change significantly in patients of group 1 (+1.2+/-1.2%), while it decreased in those of group 2 (-4.3+/-2.1%; P<0.05). After 12 months, lumbar BMD further increased (+5.9+/-1.7%, P<0.05), compared to baseline in group 1 and slightly increased (+1.1+/-1.4%) in group 2. No further changes were observed at femoral neck in both groups. In conclusion, treatment with risedronate for 12 months increased BMD significantly at the lumbar spine and prevented further bone loss at the femoral neck in long-term survivors after allo-SCT.

Avascular necrosis in long-term survivors after allogeneic or autologous stem cell transplantation: a single center experience and a review

BACKGROUND

The most debilitating skeletal complication of stem cell transplantation (SCT) is avascular necrosis (AVN).

METHODS

Two hundred seven consecutive patients were evaluated prospectively for AVN. They survived disease free for more than 180 days after autologous or allogeneic SCT for hematologic malignancies. The diagnosis of AVN in suspicious cases was confirmed by magnetic resonance imaging. Possible correlations with treatments, bone mineral density (BMD), graft versus host disease (GVHD), and in vitro growth of fibroblast progenitors were investigated. Bone mineral density was evaluated by dual-energy X-ray absorptiometry in 100 transplanted patients, and the in vitro growth of fibroblast progenitors was monitored by a fibroblast colony-forming unit (CFU-F) assay in 30 patients after allogeneic SCT.

RESULTS

Twelve patients developed AVN 3-114 months (median, 26 months) following SCT: 10 (10%) after allogeneic SCT and 2 (1.9%) after autologous SCT (P = 0.04). Twenty-five joints were affected by AVN. All patients had femoral head involvement, which was managed with hip replacement in six of them. All but one patient who developed AVN after allogeneic SCT suffered from chronic GVHD (cGVHD). Avascular necrosis occurred 1-4 months after exacerbation or progression of cGVHD. Cumulative dose of steroids was similar in both SCT groups (including steroids given pretransplant for the basic disease), whereas treatment duration was significantly longer in the allogeneic SCT group. Avascular necrosis was related to the decreased number of bone marrow CFU-F colonies in vitro, but not to BMD values.

CONCLUSIONS

Avascular necrosis is a skeletal complication that occurs more often after allogeneic than after autologous SCT. Occurrence of AVN symptoms after clinical follow-up of cGVHD suggests that cGVHD requiring long-term steroid therapy is one of the main risk factors for AVN. Avascular necrosis may be facilitated by a severe deficit in the repopulating capacity of bone marrow stromal stem cells after SCT.