Bone disease after transplantation: osteoporosis and fractures risk

Bone Loss after Solid Organ Transplantation: A Review of Organ-Specific Considerations

This review article investigates solid organ transplantation-induced osteoporosis, a critical yet often overlooked issue, emphasizing its significance in post-transplant care. The initial sections provide a comprehensive understanding of the prevalence and multifactorial pathogenesis of transplantation osteoporosis, including factors such as deteriorating post-transplantation health, hormonal changes, and the impact of immunosuppressive medications. Furthermore, the review is dedicated to organ-specific considerations in transplantation osteoporosis, with separate analyses for kidney, liver, heart, and lung transplantations. Each section elucidates the unique challenges and management strategies pertinent to transplantation osteoporosis in relation to each organ type, highlighting the necessity of an organ-specific approach to fully understand the diverse manifestations and implications of transplantation osteoporosis. This review underscores the importance of this topic in transplant medicine, aiming to enhance awareness and knowledge among clinicians and researchers. By comprehensively examining transplantation osteoporosis, this study contributes to the development of improved management and care strategies, ultimately leading to improved patient outcomes in this vulnerable group. This detailed review serves as an essential resource for those involved in the complex multidisciplinary care of transplant recipients.

Bone Disease in Long-Term Lung Transplant Survivors

Background: During the first two years after lung transplantation (LTx), the incidence of fragility fractures (FX) is estimated to be 15–50% and it is lower in patients with cystic fibrosis (CF) as compared with other end-stage lung diseases (nCF). The aim of our study is to compare the skeletal outcomes, after the first 2 years post-LTx, in long-term survivors with CF and nCF. Materials and Methods: We evaluated the FX rate, the changes in bone mineral density (BMD) and trabecular bone score (TBS) in 68 patients (38 CF and 30 nCF) who underwent LTx in our center and with a follow-up after LTx longer than 5 years (7.3 ± 2.0 years). Results: After the second year post-LTx: (i) the FX rate was lower than during the first two years post-LTx (4.4 vs. 20.6%, p = 0.004), with no difference between CF and nCF patients (5.3 vs. 3.3%, p = 0.589); (ii) BMD at lumbar spine, femoral neck and total hip remained stable (−1.6 ± 1.0 vs. −1.4 ± 1.1, p = 0.431, −1.8 ± 0.9 vs. −1.9 ± 0.9, p = 0.683, −1.5 ± 0.9 vs. −1.4 ± 0.9, p = 0.678, respectively) as well as TBS (1.200 ± 0.124 vs. 1.199 ± 0.205, p = 0.166). Conclusions: After the second year post-LTx, the skeletal complications become less frequent and have similar incidence in patients with CF and nCF.

Common Noninfectious Complications Following Lung Transplantation

According to the Scientific Registry of Transplant Recipients, both transplant volume and survival among lung transplant recipients are improving over time. However, the outcomes of lung transplantation remain challenged by multiple thoracic and extrathoracic complications. With improving lung transplant survival, patients experience prolonged exposure to chronic immunosuppressive agents that can lead to multiple infectious and noninfectious complications. This article focuses on most common noninfectious complications with significant clinical impact.

Maxillary and Mandibular Healing After Facial Allotransplantation

INTRODUCTION

Facial transplantation has emerged as a viable option in treating devastating facial injuries.Despite the high healing rate of Le Fort III and bilateral sagittal split osteotomies (BSSO) in nontransplant patients, few studies have reported assessment of maxillary and mandibular healing in face transplant patients compared with nontransplant patients. The aim of this study was to examine differences in bone healing in our patients.

PATIENTS AND METHODS

A retrospective chart review was conducted of facial allotransplantation patients at the Cleveland Clinic from December 2008 to inception. Demographics such as age, date of birth, and sex were recorded. Additional variables included procedures, revisions, reoperations, medications, and bone stability and healing. Computed tomography (CT) images assessed the alignment of skeletal components, bony union quality, and stability of fixation.

RESULTS

Three patients were included: 2 had Le Fort III segment transplantation, and 1 had transplantation of both a Le Fort III segment and mandibular BSSO. The Le Fort III segment in all patients exhibited mobility and fibrous union at the Le Fort III osteotomy on CT. In contrast, the BSSO healed uneventfully after transplantation and revision surgery, with bony union confirmed by both CT and histology of the fixation area between the donor and recipient mandible bilaterally. No patients with midfacial fibrous union required revision of the nonunion as they were clinically asymptomatic.

CONCLUSION

Le Fort osteotomy demonstrates inferior healing in facial transplantation compared with the nontransplant population. In contrast, the successful healing in the mandible is likely owing to the high density of rich cancellous bone.

Aneurysmal Bone Cyst in a Renal Transplant Patient

Aneurysmal bone cysts constitute 1% to 2% of all primary bone tumors.They are rapidly growing benign bone tumors. Nearly 80% of aneurysmal bone cysts occur in the first 20 years of life, and most are primary tumors. Aneurysmal bone cysts are mostly benign, locally aggressive, and highly vascularized tumors. Generally, the period required for postoperative recovery and new bone formation is long. The relapse rate can be up to 50%. Although computed tomography and magnetic resonance imaging scans are the preferred diagnostic methods, biopsy is the most necessary prerequisite to confirm diagnosis, as aspects of these cysts can show similarity to many other bone lesions. Correct histopathologic diagnosis is important since malignancies may be seen in transplant recipients.

Role of medicines management in preventing falls in older people

Falls are common in older people and are a cause of preventable morbidity and mortality. As well as causing injury, falls can result in pain, distress, loss of confidence, loss of independence and increased mortality. Older people are more likely to visit an emergency department following a fall, therefore these incidents place a high burden on these patients and their carers, as well as on healthcare systems. Appropriate risk assessment accompanied by multifactorial falls prevention interventions can reduce the risk of falls. Assessments should include a medication review because various medicines, sometimes referred to as 'falls risk increasing drugs', can precipitate or contribute to falls. This article examines some of the medicines in this group that can contribute to falls, serious injuries and fractures in older people. It also discusses the importance of medicines management as part of falls risk assessment and prevention interventions.

Prevalence and predictors of post-liver transplantation metabolic bone diseases

Introduction

Post-liver transplantation (LTx) bone diseases have been poorly investigated. The frequency of bone diseases (osteopenia and osteoporosis) after LTx is unknown.

Aim of the study

To define prevalence and risk factors of bone disorders following LTx.

Material and methods

This prospective study was conducted on 100 consecutive adult patients who underwent living donor liver transplantation (LDLT) at the National Liver Institute (NLI) and survived longer than a year. Bone mineral density (BMD) was evaluated by dual-energy X-ray absorption (DEXA), as well as other pre- and postoperative risk factors.

Results

The frequencies of osteopenia and osteoporosis were found to be 14% and 8% among post-LTx patients. Seven recipients of the osteoporotic group were males, with mean age, and body mass index (BMI) before and after LTx 49.5 ±7.4 years, 24.1 ±4.7 kg/m² and 22.8 ±1.5 kg/m², respectively. A significant association between hepatitis C virus (HCV)-related cirrhosis, liver disease severity according to Child-Turcotte-Pugh (CTP) score, and alcoholism with decreased post-LTx BMD was substantiated (p < 0.05, 0.006). Post-LTx development of diabetes mellitus (DM), weight gain, use of corticosteroids and basiliximab all significantly affected decreased post-LTx BMD (p < 0.05). However, binary regression revealed that post-LTx occurrence of DM (p = 0.012, odds ratio [OR] = 0.099), the severity of liver disease (p = 0.023, OR = 0.217), and HCV (p = 0.011, OR = 0.173) are the main independent predictors of metabolic bone disease (MBD) occurrence one year after LTx.

Conclusions

Post-LTx bone disorders are not infrequent complications and should be more considered in those with HCV-related severe liver disease or developed DM after LTx.

Impact of Vitamin D Supplementation on Bone Mineral Density and All-Cause Mortality in Heart Transplant Patients

Vitamin D (VD) deficiency is frequently reported in heart transplant (HT) recipients and routinely supplemented. However, the efficacy of VD supplementation on bone mineral density (BMD) and its association with all-cause mortality is underinvestigated. The VD levels and BMD were studied for two years, and the association of VD and BMD with all-cause mortality risk was investigated. Ninety-six HT patients (38.18 ± 12.10 years old; 74% men) were followed up during VD, Ca, and Mg supplementation. Anthropometric measurements, BMD by Dual-energy X-ray absorptiometry (DEXA) scan, VD concentrations, and related biochemical parameters were analyzed before, 1 year, and 2 years after HT. Despite significant improvement of VD₃ and 25-hydroxy VD (25OHVD) levels especially in the men, BMD parameters were insignificantly changed. After 2 years, the all-cause mortality rate was 15.6%. High pretransplant levels of 25OHVD failed to improve the survival probability. Cox’s regression showed a 32.7% increased hazard ratio for each unit increase in body mass index (95% CI: 1.015–1.733, p = 0.038), in the VD-deficient group rather than in the VD-sufficient one. In conclusion, VD supplementation improves the biochemical status, especially in VD-deficient HT. However, its impact on the BMD and mortality was not as usually expected. Further investigation of the disturbed VD metabolism in HT is warranted.

Impact of bone-active drugs and underlying disease on bone health after lung transplantation: A longitudinal study

INTRODUCTION

the effect of bone-active drugs on the risk of fragility fractures (Fx), bone mineral density (BMD) and trabecular bone score (TBS) changes in patients receiving lung transplantation (LTx) is largely unknown. This study assessed the bone-active drugs effect in patients undergoing LTx both with (CF) and without (nCF) cystic-fibrosis.

METHODS

We evaluated incident Fx, both clinical and morphometric vertebral Fx by spinal X-ray, BMD and trabecular bone score (TBS) in 117 patients (CF=50, nCF n = 67) before and 24-months after LTx. A bone-active therapy was proposed to all LTx candidates.

RESULTS

83.8% of patients started a bone-active drug. Lumbar-spine (LS) T-score improved significantly only in treated patients (-1.4 ± 1.0 vs -2.0±1.0, p = 0.0001), whereas femur BMD and TBS remained stable in treated and not treated subjects. The rate of incident Fx was 15.3%, with no difference between treated and not treated patients. After LTx, LS T-score improved significantly only in nCF group (-1.3 ± 1.0 vs -1.8 ± 1.1, p = 0.0001), while femur remained stable in both nCF and CF groups. Patients with CF showed a significant Z-TBS increase (-3.6 ± 1.7 vs -3.0 ± 1.7, p = 0.019) and a lower Fx incidence as compared with nCF patients (4.1% vs 24.2%, p  =0.003). Incident Fx were associated with nCF diagnosis (OR 7.300, CI95% 1.385-38.461, p = 0.019) regardless of prevalent Fx, previous glucocorticoid therapy and bone-active therapy introduced at least 6 months before LTx.

CONCLUSIONS

A prompt medical intervention helps in preventing BMD loss after LTx. As compared with nCF patients, CF patients show a TBS increase and a lower Fx risk after LTx.

Risk Factors for Hematopoietic Stem Cell Transplantation-Associated Bone Loss

Hematopoietic stem cell transplantation (HSCT), including bone marrow transplantation, is the treatment of choice for many hematologic diseases, including hematologic malignancies and different types of anemia. The use of HSCT is increasing annually, mainly because advanced research that has been conducted in this area has exponentially expanded the indications for HSCT and significantly improved transplantation techniques and supportive care practices. Collectively, these improvements have led to an increase in the overall survival of HSCT patients. However, as post-HSCT survival is increasing, awareness of the potential late complications of HSCT is also growing. Unpredictable bone loss is one of the major post-HSCT complications that can cause significant morbidity and impair the quality of life of survivors. Although the exact mechanism of post-HSCT bone loss is not yet known, previous studies have suggested that numerous factors, including destructive preparative regimens (eg, high-dose chemotherapy, total body irradiation), treatment-related complications (eg, graft-versus-host disease), endocrine abnormalities (eg, diabetes mellitus, thyroid dysfunction, adrenal insufficiency), lack of physical activity, and the underlying disease itself are responsible for HSCT-associated bone loss. Sufficient data have been collected to suggest that post-HSCT bone loss can be prevented and treated using the same preventive and treatment modalities as used for the general population. Various guidelines have been formulated to help keep a check on HSCT recipients' deteriorating bone health.

Factors Affecting Bone Health in Kidney Transplant Recipients: Klotho Gene Single-Nucleotide Polymorphisms and Other Clinical Features

OBJECTIVES

Posttransplant bone diseases are a major cause of morbidity in kidney transplant recipients. We investigated the relationship between klotho gene single-nucleotide polymorphisms and bone diseases after kidney transplant. We also aimed to identify possible risk factors for development of bone disease.

MATERIALS AND METHODS

The study consisted of 251 kidney transplant recipients (164 men and 87 women) with minimum follow-up of 3 years after kidney transplant. Patients with prolonged immobilization, malignancy, parathyroidectomy, glomerular filtration rates less than 30 mL/min/1.73 m², hypo- or hyperthyroidism, and treatment with drugs that affect bone metabolism were excluded. We investigated the relationship between 6 single-nucleotide polymorphisms of the klotho gene (rs480780, rs211234, rs576404, rs211235, rs9536314, and rs1207568) and development of osteoporosis, avascular bone necrosis, and persistent hyperparathyroidism.

RESULTS

Longer dialysis treatment (odds ratio, 1.13; P = .002) and rs211235 single-nucleotide polymorphism in the klotho gene (odds ratio, 9.87; P = .001 for GG genotype) were significantly associated with persistent hyperparathyroidism. A higher magnesium level was detected as a protective factor from development of persistent hyperparathyroidism (odds ratio, 0.19; P = .009). Persistent hyperparathyroidism was defined as a risk factor for development of osteopenia/osteoporosis (odds ratio, 2.76; P = .003) and avascular bone necrosis (odds ratio, 2.52; P= .03). Although the rs480780 (odds ratio, 8.73; P = .04) single-nucleotide polymorphism in the klotho gene was defined as a risk factor for development of osteopenia/osteoporosis, none of the klotho single-nucleotide polymorphisms was found to be associated with development of avascular bone necrosis.

CONCLUSIONS

Persistent hyperparathyroidism could be an important indicator for development of bone disease in kidney transplant recipients. Also, some of the klotho gene single-nucleotide polymorphisms are associated with higher risk for bone disease after kidney transplant.

Timing of Osteoporotic Vertebral Fractures in Lung and Heart Transplantation: A Longitudinal Study

Bone loss and bone fractures are common complications after organ transplantation. Many factors contribute to the pathogenesis of transplant osteoporosis, such as bone disease preceding transplantation, immunosuppressive medications, and nutritional and lifestyle factors. This study aimed to assess the incidence of vertebral fractures before and after lung and heart transplantation. This longitudinal study analyzed 213 electronic medical records of patients who underwent lung transplantation (n = 128) and heart transplantation (n = 85) at Siena University Medical Center between January 2000 and December 2018. In lung and heart transplant recipients, the bone mineral density in the femoral sub-regions show a significant decrease at post-transplantation and at follow up visits. In both lung and heart recipients, we found an increase in the fracture incidence in the first period after transplantation (19.5% vs. 50.4% in lung recipients; 9.6% vs. 25.7% in heart recipients). Moreover, in lung recipients, vertebral fractures were predicted primarily by age, BMD at the femur, and any history of fracture. In heart recipients, vertebral fractures were predicted only by history of fracture. Our study supports the recommendations for pre-transplant osteoporosis screening in patients undergoing lung transplants, and in the first period after transplantation in heart transplant recipients.

Risk Factors and Management of Osteoporosis Post-Transplant

Bone and mineral disorders are common after organ transplantation. Osteoporosis post transplantation is associated with increased morbidity and mortality. Pathogenesis of bone disorders in this particular sub set of the population is complicated by multiple co-existing factors like preexisting bone disease, Vitamin D deficiency and parathyroid dysfunction. Risk factors include post-transplant immobilization, steroid usage, diabetes mellitus, low body mass index, older age, female sex, smoking, alcohol consumption and a sedentary lifestyle. Immunosuppressive medications post-transplant have a negative impact on outcomes, and further aggravate osteoporotic risk. Management is complex and challenging due to the sub-optimal sensitivity and specificity of non-invasive diagnostic tests, and the underutilization of bone biopsy. In this review, we summarize the prevalence, pathophysiology, diagnostic tests and management of osteoporosis in solid organ and hematopoietic stem cell transplant recipients.

Solid Organ Transplant Is Associated With Increased Morbidity and Mortality in Patients Undergoing One or Two-level Anterior Cervical Decompression and Fusion

STUDY DESIGN

Retrospective database review OBJECTIVE.: The aim of this study was to analyze the implications of solid organ transplant (SOT) on postoperative outcomes following elective one or two-level anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

Although SOTs have been associated with increased morbidity, postoperative outcomes in SOT recipients undergoing cervical spinal surgery are not well studied.

METHODS

A retrospective database review of Medicare patients younger than 85 years who underwent an elective one to two-level ACDF from 2006-2013 was conducted. Following our exclusion criteria, patients were then divided into the following groups: those with a prior history of kidney, liver, heart or lung transplant (SOT group) and non-SOT patients. Both groups were compared for hospital length of stay, 90-day major medical complications, 90-day hospital readmission, 1-year surgical site infection (SSI), 1-year revision ACDF, and 1-year mortality.

RESULTS

A total of 992 (0.5%) SOT recipients (1,144 organs) were identified out of 199,288 ACDF patients. SOT recipients had a significantly longer length of stay (2.32 vs. 5.22 days, p<0.001), higher rate of major medical complications (8.2% vs. 4.5%; OR 1.85, 95% CI 1.45-2.33, p<0.001) and hospital readmission (19.5% vs. 7.5%, OR 2.05, 95% CI 1.74-2.41, p<0.001). In addition, SOT patients had increased mortality within one year of surgery (5.8% vs. 1.3%; OR 3.01, 95% CI 2.26-3.94, p<0.001) compared to non-SOT patients. SOT was not independently associated with SSI (OR 1.25, 95% CI 0.85-1.75, p=0.230), and there was no significant difference in revision rate (0.9% vs. 0.5%; OR 1.54, 95% CI 0.73-2.82, p=0.202) between both groups.

CONCLUSION

SOT is independently associated with longer hospital stay, increased rate of major medical complications, hospital readmission and mortality. Spine surgeons should be aware of the higher rates of morbidity and mortality in these patients and take it into consideration when developing patient-specific treatment plans.

LEVEL OF EVIDENCE

3.

The use of selective estrogen receptor modulators on bone health in men

Selective estrogen receptor modulators (SERMs) represent a class of drugs that act as agonist or antagonist for estrogen receptor in a tissue-specific manner. The SERMs drugs are initially used for the prevention and treatment of osteoporosis in postmenopausal women. Bone health in prostate cancer patients has become a significant concern, whereby patients undergo androgen deprivation therapy is often associated with deleterious effects on bone. Previous preclinical and epidemiological findings showed that estrogens play a dominant role in improving bone health as compared to testosterone in men. Therefore, this evidence-based review aims to assess the available evidence derived from animal and human studies on the effects of SERMs on the male skeletal system. The effects of SERMs on bone mineral density (BMD)/content (BMC), bone histomorphometry, bone turnover, bone strength and fracture risk have been summarized in this review.

Effects of denosumab on bone metabolism and bone mineral density in kidney transplant patients: a systematic review and meta-analysis

OBJECTIVE

The use of immunosuppressive agents, especially glucocorticoids, are associated with increased risks of bone loss in kidney transplant patients. Denosumab, a potent antiresorptive agent, has been shown to increase bone mineral density (BMD) in patients with CKD. However, its effects on bone metabolism and BMD in kidney transplant patients remain unclear.

METHODS

A literature search was conducted using MEDLINE, EMBASE, and Cochrane Database from inception through April 2018 to identify studies evaluating denosumab's effect on changes in bone metabolism and BMD from baseline to post-treatment course in kidney transplant patients. Study results were pooled and analyzed utilizing random-effects model. The protocol for this systematic review is registered with PROSPERO (International Prospective Register of Systematic Reviews; no. CRD42018095055).

RESULTS

Five studies (a clinical trial and four cohort studies) with a total of 162 kidney transplant patients were identified. The majority of patients had a baseline eGFR ≥ 30 mL/min/1.73 m². After treatment (≥ 6 to 12 months), there were significant increases in BMD with standardized mean differences (SMDs) of 3.26 (95% CI 0.88-5.64) and 1.83 (95% CI 0.43 to 3.22) for lumbar spine and femoral neck, respectively. There were also significant increases in T scores with SMDs of 0.92 (95% CI 0.58 to 1.25) and 1.14 (95% CI 0.17 to 2.10) for lumbar spine and femoral neck, respectively. After treatment, there were no significant changes in serum calcium (Ca) or parathyroid hormone (PTH) from baseline to post-treatment course (≥ 6 months) with mean differences (MDs) of 0.52 (95% CI, - 0.13 to 1.16) mmol/L and - 13.24 (95% CI, - 43.85 to 17.37) ng/L, respectively. The clinical trial data demonstrated more asymptomatic hypocalcemia in the denosumab (12 episodes in 39 patients) than in the control (1 episode in 42 patients) group. From the cohort studies, the pooled incidence of hypocalcemia following denosumab treatment was 1.7% (95% CI 0.4 to 6.6%). All reported hypocalcemic episodes were mild and asymptomatic, but the majority of patients required Ca and vitamin D supplements.

CONCLUSION

Among kidney transplant patients with good allograft function, denosumab effectively increases BMD and T scores in the lumbar spine and femur neck. From baseline to post-treatment, there are no differences in serum Ca and PTH. However, mild hypocalcemia can occur following denosumab treatment, requiring monitoring and titration of Ca and vitamin D supplements.

A 5-Year Follow-Up of The Benefits of an Exercise Training Program in Liver Recipients Transplanted Due to Familial Amyloidotic Polyneuropathy

BACKGROUND

Supervised (SE) and home-based exercise (HBE) training regimes are effective on reconditioning patients with familial amyloidotic polyneuropathy (FAP) after liver transplantation, but research of the long-term retention of the benefits attained in patients with FAP has not yet been conducted.

PURPOSE

In this 5-year follow-up study, we aimed to determine whether the exercise training gains in body composition, physical activity, and function promoted by a 24-week SE or HBE training regimes are retained in patients with FAP who resume normal activity.

METHODOLOGY

Sixteen liver-transplanted patients with FAP were reassessed for body composition (dual X-ray absorptiometry), physical activity (questionnaire), and function (handgrip strength and 6-minute walk test).

RESULTS

Total body fat increased with both exercise regimes during follow-up ( P < .05; η² = 0.432-0.625) as well as femoral neck bone density ( P = .048; η² = 0.119). However, gains in upper limbs muscle quality during follow-up ( P < .001; η² = 0.597) were only found in the SE group ( P = .042; η² = 0.245). Both exercise regimes showed retaining aptitudes in walking capacity ( P < .05; η² = 0.329-0.460) and muscle mass ( P = .05; η² = 0.245). Still, none could retain the physical activity levels.

CONCLUSION

Long-term resumption of normal activity following a 24-week SE or HBE regime in patients with FAP resulted in loss of exercise induced increases in physical activity but counterweighted postoperative losses in bone mineral density and substantially retained the benefits in walking capacity, muscle mass, and quality, in particular, in the SE group.

Lumbar Spine Fusion Surgery in Solid Organ Transplant Recipients Is Associated With Increased Medical Complications and Mortality

STUDY DESIGN

Retrospective database review.

OBJECTIVE

To characterize the outcomes of solid organ transplant (SOT) patients after one- or two-level lumbar fusion surgery.

SUMMARY OF BACKGROUND DATA

Over the past decade advances in SOT patients have improved graft survival. As such, this patient population is increasingly eligible for elective surgery such as lumbar fusion procedures to improve mobility and quality of life. However, the outcomes of spine surgery in this population are not well defined.

METHODS

Data from the full 100% Medicare sample between 2005 and 2014 were used for the study. Patients were included if they had an elective one- or two-level lumbar spine fusion and previous history of renal, heart, liver, or lung SOT patients during this period. SOT patients were compared to non-SOT patients with respect to baseline characteristics, 90-day medical complications, 1-year rate of revision surgery, and 1-year mortality.

RESULTS

There were 961 patients in the transplant cohort and 258,342 in the non-SOT cohort. Seventy-seven percent of the SOT patients had prior renal transplant. SOT patients had a longer length of stay (P < 0.001), and a higher 30-day readmission rate compared to non-SOT patients (P =  < 0.001). In addition, SOT patients experienced a 23.8% rate of 90-day postoperative major medical complications and 3.0%, 1-year mortality, significantly larger than respective rates in the control population (P < 0.001). One-year infection, revision surgery rates, and wound dehiscence were not significantly different between the two cohorts.

CONCLUSION

Spine surgery is associated with significant medical complications and 1-year mortality in the SOT population. Although there may be a substantial benefit from lumbar fusion in the SOT population, judicious patient selection is of paramount importance.

LEVEL OF EVIDENCE

3.

Progression of Osteoporosis After Kidney Transplantation in Patients With End-Stage Renal Disease

BACKGROUND

This study investigated the prevalence of osteoporosis and the risk factors for its progression in kidney transplant recipients (KTRs).

METHODS

Dual energy X-ray absorptiometry was used to prospectively measure changes in bone mineral density (BMD) before kidney transplantation (KT) and 1 year after transplantation in 207 individuals. We also analyzed the risk factors of osteoporosis progression during this period.

RESULTS

Prior to KT, the mean BMD score (T-score of the femur neck area) was -2.1 ± 1.2, and the prevalence of osteoporosis was 41.5% (86/207). At 1 year post-transplantation, the mean BMD score significantly decreased to -2.3 ± 1.1 (P < .001), and the prevalence of osteoporosis increased to 47.3% (98/207; P = .277). The BMD score worsened over the study period in 69.1% (143/207) of patients, improved in 24.1% (50/207), and showed no change in 6.8% (14/207). Minimal intact parathyroid hormone (iPTH) improvement after KT was found to be an independent risk factor of osteoporosis progression.

CONCLUSIONS

This study demonstrates progressive loss of BMD after KT and sustained secondary hyperparathyroidism might influence the progression of osteoporosis.

Osteoporosis in Pediatric Liver Transplantation

Liver transplantation provides an important, often life-saving treatment for end-stage liver disease. Osteoporosis post-liver transplantation has been described in adults; however, this has not been described in the pediatric population to date. We present a case of a 13-year-old female patient who underwent an orthotopic liver transplant for cryptogenic liver cirrhosis. Her immunosuppressants were tacrolimus and prednisone. Four months posttransplant, she started complaining of bilateral lower limb pain and limping while walking, progressing to a point where she was almost immobile. Magnetic resonance imagining of the pelvis showed bilateral avascular necrosis involving the weight-bearing surfaces of both femoral heads, in addition to the extensive edema involving both hip joints. Bone mineral densitometry was below normal for her age at the hip and forearm. She was started on high-dose calcium and vitamin D supplement, as well as zoledronic acid with a remarkable symptomatic and functional improvement.

Osteoporosis across chronic liver disease

Osteoporosis is a complication of chronic liver disease, with impact on morbidity, quality of life, and survival. The progress of medicine and the new therapies stretched the disease's natural history and improved the survival of patients with liver disease. So, it is fundamental to make better the quality of life and to prevent complications. Metabolic bone disorders are common complications of chronic liver disease (CLD). Patients with CLD have an increased risk of bone fractures, with significant impact on morbidity, quality of life, and even on survival. Bone diseases, including osteomalacia, osteoporosis, and osteopenia, are frequently observed in many types of liver disease. The pathogenesis of damage and the mechanisms of bone loss are different in relation to the specific liver disease. The relevance of these conditions induced many authors to create a new nosographic entity known as "hepatic osteodystrophy", although this term is rarely used anymore and it is now commonly referred to as osteopenia or osteoporosis associated with chronic liver disease. This review is based on the personal experiences of the authors and upon research done of the available literature on this subject matter. The authors searched the PubMed database for publications containing the term "liver disease" in combination with "bone disease", "hepatic osteodistrophy", "osteoporosis", "osteopenia", "osteomalacia", and "fractures". They selected publications from the past 10 years but did not exclude older seminal publications, especially for colestatic liver diseases. This review of literature shows that osteoporosis crosses all CLD. It is important to underline that the progress of medicine and the new therapies stretched the disease's natural history and improved the survival of patients with CLD. It is fundamental to make better the quality of life and it is mandatory to prevent complications and in particular the osteoporotic ones, especially fractures.

Bone disease in post-transplant patients

PURPOSE OF REVIEW

Mineral and bone disorders are common problems in organ transplant recipients. Successful transplantation solves many aspects of abnormal mineral and bone metabolism, but the degree of improvement is frequently incomplete. Posttransplant bone disease can affect long-term outcomes as well as increase the likelihood of fracture. In this article, we reviewed the major posttransplant bone diseases and recent advances in treatment strategies.

RECENT FINDINGS

Pretransplant bone disease and immunosuppressants are important risk factors for posttransplant bone disease. Corticosteroid withdrawal may result in minimal or no protection against fractures, with increased risk for acute rejection. Vitamin D analogue and bisphosphonate are frequently used to prevent and treat posttransplant osteoporosis. Posttransplant hyperparathyroidism increases the risk for all-cause mortality and graft loss, but not major cardiovascular events. Cinacalcet was well tolerated and effectively controlled hypercalcemic hyperparathyroidism; however, it did not improve bone mineral density and discontinuation led to parathyroid hormone rebound. Six-month paricalcitol supplementation reduced parathyroid hormone levels and attenuated bone remodeling and mineral loss in case of posttransplant hyperparathyroidism.

SUMMARY

Posttransplant bone diseases present in various forms, including osteoporosis, hyperparathyroidism, adynamic bone disease, and osteonecrosis. Prophylactic and therapeutic approaches to both pretransplant and posttransplant periods should be considered.