Bone metabolism and gonad function in male patients undergoing liver transplantation: a two-year longitudinal study

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.

Fractal characteristics of the trabecular pattern of the mandible in patients with renal transplantation

OBJECTIVE

In this study, we examined the mandibular trabecular bone structures by performing fractal dimension (FD) analysis in patients who underwent renal transplantation (RTx).

METHODS

Our study is an observational study with 69 RTx patients and 35 control group patients. The mean FD values of the patient and control groups were calculated and compared. In addition, biochemical parathyroid hormone (PTH), serum calcium, phosphorus, alkaline phosphatase (ALP), and vitamin-D parameters and FD values of both groups were analyzed.

RESULTS

FD values were significantly lower in the patient group than in the healthy group (p < .05). In the RTx group compared to the control group, ALP (90.71 ± 34.25-66.54 ± 16.8, respectively) (p < .001) and PTH (75.76 ± 38.01-38.17 ± 12.39, respectively) (p < .001) values were higher. There was a positive correlation between the FD values and ALP (rspearman  = .305, p = .011) and a negative correlation between FD values and vitamin-D (rspearman  = .287, p = .017) of patients with RTx.

CONCLUSION

FD values were found to be lower in patients who underwent RTx compared to the control group. It should be considered that FD analysis can be a method that can be used to evaluate trabecular bone structure in patients undergoing RTx.

High risk of osteoporosis and fracture following solid organ transplantation: a population-based study

Background

Osteoporosis and fractures increase morbidity and mortality rates after solid organ transplantation (SOT), but few studies have analyzed the risk of osteoporosis and related fractures after SOT. In this retrospective cohort study, we investigated the risk of osteoporosis and fractures in different SOT recipients.

Methods

This study was a retrospective cohort study using a nationally representative database in Taiwan. We collected the data of SOT recipients and used the propensity score matching method to obtain a comparison cohort. To reduce bias, we excluded patients who had been diagnosed with osteoporosis or fracture before inclusion. All participants were followed up until the date of diagnosis as having a pathological fracture, death, or the end of 2018, whichever occurred first. The Cox proportional hazards model was used to investigate the risk of osteoporosis and pathological fracture in SOT recipients.

Results

After adjustment for the aforementioned variables, SOT recipients were observed to have a higher risk of osteoporosis (hazard ratio (HR) = 1.46, 95% confidence interval (CI): 1.29-1.65) and fracture (HR: 1.19, 95% CI: 1.01-1.39) than the general individuals. Among the different SOT recipients, the highest risk of fractures was noted in heart or lung transplant recipients, with a HR of 4.62 (95% CI: 2.05-10.44). Among the age groups, patients aged >61 years had the highest HRs for osteoporosis (HR: 11.51; 95% CI, 9.10-14.56) and fracture (HR: 11.75, 95% CI: 8.97-15.40).

Conclusion

SOT recipients had a higher risk of osteoporosis and related fractures than the general population, with the highest risks observed in patients receiving heart or lung transplants, older patients, and patients with CCI scores of >3.

Testosterone deficiency in male organ transplant recipients

Testosterone deficiency is known to affect men with increasing incidence throughout their lifespan. The clinical manifestations of testosterone deficiency, in turn, negatively impact men's quality of life and perception of overall health. The interaction of chronic systemic disease and androgen deficiency represent an area for potential intervention. Here, we explore the topic of testosterone deficiency amongst men with end-stage organ failure requiring transplantation in order to elucidate the underlying pathophysiology of androgen deficiency of chronic disease and discuss whether intervention, including testosterone replacement and organ transplantation, improve patients' outcomes and quality of life.

Bone Health in Patients With Liver Diseases

Osteoporosis is the most common bone disease in chronic liver disease (CLD) resulting in frequent fractures and leading to significant morbidity in this population. In addition to patients with cirrhosis and chronic cholestasis, patients with CLD from other etiologies may be affected in the absence of cirrhosis. The mechanism of osteoporosis in CLD varies according to etiology, but in cirrhosis and cholestatic liver disease it is driven primarily by decreased bone formation, which differs from the increased bone resorption seen in postmenopausal osteoporosis. Direct toxic effects from iron and alcohol play a role in hemochromatosis and alcoholic liver disease, respectively. Chronic inflammation also has been proposed to mediate bone disease in viral hepatitis and nonalcoholic fatty liver disease. Treatment trials specific to osteoporosis in CLD are small, confined to primary biliary cholangitis and post-transplant patients, and have not consistently demonstrated a benefit in this population. As it stands, prevention of osteoporosis in CLD relies on the mitigation of risk factors such as smoking and alcohol use, treatment of underlying hypogonadism, and encouraging a healthy diet and weight-bearing exercise. The primary medical intervention for the treatment of osteoporosis in CLD remains bisphosphonates though a benefit in terms of fracture reduction has never been shown. This review outlines what is known regarding the pathogenesis of bone disease in CLD and summarizes current and emerging therapies.

Osteoporosis in chronic liver disease

Osteoporosis is a frequent complication in patients with chronic liver disease, especially in end-stages and in chronic cholestasis, in addition to non-alcoholic fatty liver disease, haemochromatosis and alcoholism. Mechanisms underlying osteoporosis are poorly understood, but osteoporosis mainly results from low bone formation. In this setting, sclerostin, a key regulator of the Wnt/β-catenin signalling pathway which regulates bone formation, in addition to the effects of the retained substances of cholestasis such as bilirubin and bile acids on osteoblastic cells, may influence the decreased bone formation in chronic cholestasis. Similarly, the damaging effects of iron and alcohol on osteoblastic cells may partially explain bone disease in haemochromatosis and alcoholism. A role for proinflammatory cytokines has been proposed in different conditions. Increased bone resorption may occur in cholestatic women with advanced disease. Low vitamin D, poor nutrition and hypogonadism, may be contributing factors to the full picture of bone disorders in chronic liver disease.

Bone metabolism dynamics in the early post-transplant period following kidney and liver transplantation

Bone disease contributes to relevant morbidity after solid organ transplantation. Vitamin D has a crucial role for bone metabolism. Activation of vitamin D depends on the endocrine function of both, liver and kidney. Our study assessed key markers of bone metabolism at time of transplantation and 6 months after transplantation among 70 kidney and 70 liver recipients. In 70 kidney recipients 25-OH vitamin D levels did not differ significantly between peri-transplant (median 32.5nmol/l) and 6 months post-transplant (median 41.9nmol/l; P = 0.272). Six months post-transplant median 1, 25-(OH)₂ vitamin D levels increased by >300% (from 9.1 to 36.5ng/l; P<0.001) and median intact parathyroid hormone levels decreased by 68.4% (from 208.7 to 66.0 ng/l; P<0.001). Median β-Crosslaps (CTx) and total procollagen type 1 amino-terminal propeptide (P1NP) decreased by 65.1% (from 1.32 to 0.46ng/ml; P<0.001) and 60.6% (from 158.2 to 62.3ng/ml; P<0.001), respectively. Kidney recipients with incident fractures had significantly lower levels of 1, 25-(OH)₂ vitamin D at time of transplantation and of intact parathyroid hormone 6 months post-transplant. Among 70 liver recipients, 25-OH vitamin D, 1, 25-(OH)₂ vitamin D and intact parathyroid hormone levels were not significantly altered between peri-transplant and 6 months post-transplant. Contrary to kidney recipients, median CTx increased by 60.0% (from 0.45 to 0.72 ng/ml; P = 0.002) and P1NP by 49.3% (from 84.0 to 125.4ng/ml; P = 0.001) in the longitudinal course. Assessed biomarkers didn’t differ between liver recipients with and without fractures. To conclude, the assessed panel of biomarkers proved highly dynamic after liver as well as kidney transplantation in the early post-transplant period. After kidney transplantation a significant gain in 1, 25-(OH)₂ vitamin D combined with a decline in iPTH, CTx and P1NP, whereas after liver transplantation an increase in CTx and P1NP were characteristic.

Effects of liver transplantation on endocrine function: a systematic review

Patients with chronic liver disease (CLD) often experience secondary endocrine dysfunction. Therefore, because the liver plays a major role in endocrine function, liver transplantation (LT) may also be beneficial for the restoration of hormonal regulation. This systematic review collects and interprets the available literature on the effect of LT on endocrine and sexual function in adult patients. A systematic review was conducted by searching Pubmed (including Medline) and EMBASE for studies published from database inception until November 2015. We collected all relevant studies that discussed changes in hormonal and sexual function after LT. Studies were included if they assessed the effect of LT on sexual function or one of the following components of the hormone/endocrine axis: the hypothalamus-pituitary-gonadal axis, growth hormone (GH), insulin-like growth factor-1 (IGF-1) or thyroid function. The results are reported according to the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. Twenty-one studies with a total of 1274 patients were included. The results collected from the included studies suggested that LT improves the hormonal perturbation associated with CLD by restoring physiological levels of circulating GH, IGF-1, testosterone, estradiol, prolactin, follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Thyroid function was not affected by LT, and sexual function was partially improved after LT. This systematic review suggests that LT is associated with an improvement in endocrine and sexual function in patients with CLD. This information should encourage clinicians who treat CLD patients to identify endocrine disturbances in this population, inform their patients of the effects of LT and assess post-transplantation improvements.

Hypothalamic-pituitary-gonadal function in men with liver cirrhosis before and after liver transplantation

Objective: To evaluate the influence of end-stage liver disease and orthotopic liver transplantation in the pituitary function and hormone metabolism before and after liver transplantation.Methods: In a prospective study, serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2) and prolactin (PRL) of 30 male patients with cirrhosis were determined two to four hours before and six months after liver transplantation. The results were compared according to the Model for End-stage Liver Disease (MELD).Results: male patients with liver cirrhosis have hypogonadism. FSH was normal, but inappropriately low due to androgen failure; E2 and PRL, on their turn, were high. After liver transplantation, FSH and LH levels increased (p < 0.05), whereas E2 and PRL normalized (p < 0.05). The MELD score did not influence changes in FSH, PRL and LH, however, the more severe the cirrhosis was, the more significant was the normalization of E2 (p = 0.01).Conclusion: Patients with cirrhosis and male hypogonadism have inappropriately normal levels of FSH and LH, associated with an increase in E2 and LRP. After liver transplantation, FSH and LH increased, while E2 and PRL returned to normal. Changes in E2 levels were most pronounced in patients with MELD > 18. The severity of cirrhosis had no influence on FSH, PRL and LH.

Testosterone changes in patients with liver cirrhosis before and after orthotopic liver transplantation and its correlation with MELD

CONTEXT

Hypogonadism is a common clinical situation in male patients with liver cirrhosis.

OBJECTIVES

The aim of the present study was to evaluate the effects of orthotopic liver transplantation on testosterone, free testosterone and sex hormone-binding globulin in male with advanced liver disease and also to determine the relationship of these changes with Model for End-stage Liver Disease (MELD) score.

METHODS

In a prospective study, serum levels of testosterone, free testosterone and sex hormone-binding globulin of 30 male adult patients with end-stage liver disease were measured 2 to 4 hours before and 6 months after orthotopic liver transplantation.

RESULTS

Total testosterone levels increased after orthotopic liver transplantation and the number of patients with normal testosterone levels increased from 18 to 24. Free testosterone mean level in the pre-transplant group was 7.8 pg/mL and increased to 11.5 pg/mL (P = 0.10) and sex hormone-binding globulin level decreased after orthotopic liver transplantation returning to normal levels in MELD ≤ 18 - group (A) (P<0.05).

CONCLUSIONS

Serum level changes of testosterone, free testosterone and sex hormone-binding globulin are more pronounced in cirrhotic males with MELD ≤ 18. Serum levels of testosterone and free testosterone increase and serum levels of sex hormone-binding globulin decrease after orthotopic liver transplantation.

Longitudinal changes in BMD and fracture risk in orthotopic liver transplant recipients not using bone-modifying treatment

Osteoporosis is prevalent in end-stage liver disease, but data on long-term changes in bone mineral density (BMD) and related fracture incidence after orthotopic liver transplantation (OLT) are scarce. We evaluated BMD changes up to 5 years in consecutive recipients of a successful OLT at the Leiden University Medical Centre between 2000 and 2011, in whom sequential BMD data were available. Spinal radiographs were available at time of screening and at 6 and 12 months post-OLT and were assessed for vertebral fractures by two independent observers using Genant's semiquantitative method. Patients were excluded from the study when started on bisphosphonates. A total of 201 patients (71% men), median age 53 years (range, 18-70 years) were included in the study. Most common liver pathology was viral (27%) or alcoholic liver disease (25%). All patients received prednisone for at least 6 months after transplantation and the majority received either tacrolimus or cyclosporine for immunosuppression. At time of screening for OLT, osteoporosis and osteopenia were found in 18% and 36% of patients at the lumbar spine (LS), respectively, and in 9% and 42% at the femoral neck (FN), respectively. T-scores declined significantly at both sites 6 months after OLT, but increased thereafter at the LS, reaching pretransplantation values at 2 years and remaining stable thereafter. FN T-scores remained consistently lower than pretransplantation values. The prevalence of vertebral fractures increased from 56% at screening to 71% at 1 year after OLT, with a fracture incidence of 34%. BMD changes did not predict fracture risk. Osteoporosis, osteopenia, and vertebral fractures are prevalent in patients with end-stage liver disease. An overall decline in BMD is observed within the first 6 months after OLT, with subsequent recovery to pretransplantation values at the LS, but not at the FN. Vertebral fracture risk is high after OLT regardless of changes in BMD.

Osteoporosis and fractures after solid organ transplantation: a nationwide population-based cohort study

OBJECTIVE

To investigate the incidence of bone disorders after solid organ transplantation (SOT).

PARTICIPANTS AND METHODS

We used Taiwan's National Health Insurance Research Database to identify 9428 recipients of SOT and 38,140 sex- and age- matched control subjects between January 1, 1997, and December 31, 2010, to compare the incidence and risk of bone disorders between groups.

RESULTS

Recipients of SOT had a significantly higher incidence of osteoporosis and related fractures compared with the non-SOT group. The overall hazard ratio (HR) of osteoporosis after SOT was 5.14 (95% CI, 3.13-8.43), and the HR of related fractures was 5.76 (95% CI, 3.80-8.74). The highest HRs were observed in male patients (HR, 7.09; 95% CI, 3.09-16.3) and in those aged 50 years or younger (HR, 7.38; 95% CI, 2.46-22.1). In addition, SOT patients without any comorbidities had a 9.03-fold higher risk of osteoporosis than non-SOT participants (HR, 9.03; 95% CI, 5.29-15.4). To compare the risk of osteoporosis and related fractures in different recipients of SOT, the highest risk of osteoporosis and fractures was noted in patients receiving lung transplantation, followed by other types of SOT.

CONCLUSION

We report high rates of metabolic bone disorders after SOT in chronic transplant patients over a long follow-up. Both underlying bone disorders before transplantation and use of immunosuppressant agents may contribute to bone disorders after transplantation.

Why Healthcare Providers Should Focus on the Fertility of AYA Cancer Survivors: It's Not Too Late!

Reproductive health among cancer survivors is an important quality of life issue. Certain cancer therapies have known fertility risks. There is an existing cohort of adolescents and young adults (AYA) cancer survivors that, seen less frequently in clinical care settings than active patients, are likely not having discussions of fertility and other reproductive health issues. A survivor or healthcare provider can easily assume that the window of opportunity for fertility preservation has passed, however emerging research has shown this may not be the case. Recent data demonstrates a close relationship between fertility and other late effects to conclude that ongoing assessment during survivorship is warranted. Some fertility preservation procedures have also been shown to mitigate common late effects. This review explores the link between late effects from treatment and common comorbidities from infertility, which may exacerbate these late effects. This review also highlights the relevance of fertility discussions in the AYA survivorship population.

Endocrine and bone metabolic complications in chronic liver disease and after liver transplantation in children

With improved survival of orthotopic liver transplantation (OLT) in children, prevention and treatment of pre- and posttransplant complications have become a major focus of care. End-stage liver failure can cause endocrine complications such as growth failure and hepatic osteodystrophy, and, like other chronic illnesses, also pubertal delay, relative adrenal insufficiency, and the sick euthyroid syndrome. Drug-induced diabetes mellitus post-OLT affects approximately 10% of children. Growth failure is found in 60% of children assessed for OLT. Despite optimisation of nutrition, rarely can further stunting of growth before OLT be prevented. Catch-up growth is usually observed after steroid weaning from 18 months post-OLT. Whether growth hormone treatment would benefit the 20% of children who fail to catch up in height requires testing in randomised controlled trials. Hepatic osteodystrophy in children comprises vitamin D deficiency rickets, low bone mass, and fractures caused by malnutrition and malabsorption. Vitamin D deficiency requires aggressive treatment with ergocalciferol (D2) or cholecalciferol (D3). The active vitamin D metabolites alphacalcidol or calcitriol increase gut calcium absorption but do not replace vitamin D stores. Prevalence of fractures is increased both before OLT (10%-28% of children) and after OLT (12%-38%). Most fractures are vertebral, are associated with low spine bone mineral density, and frequently occur asymptomatically, but they may also cause chronic pain. Fracture prediction in these children is limited. OLT in children is also associated with a greater risk of developing avascular bone necrosis (4%) and scoliosis (13%-38%). This article reviews the literature on endocrine and skeletal complications of liver disease and presents preventive screening recommendations and therapeutic strategies.

Vitamin D in organ transplantation

Vitamin D deficiency is prevalent among patients with end-stage organ failure awaiting transplant. Low serum 25-hydroxyvitamin D (25-OHD) levels in these patients may be related to many disease-specific factors, as well as decreased sunlight exposure and limited intake of foods containing vitamin D. Low serum 25-OHD levels are also extremely common following solid organ transplantation, both during the immediate postoperative period and in long-term graft recipients. Demographic and lifestyle factors are important in determining D status in transplant recipients. Worse vitamin D status is associated with poorer general health, lower albumin, and even decreased survival among these patients. Although several studies have demonstrated that active forms of vitamin D and its analogues prevent bone loss following transplantation, the data do not show consistent benefit. These therapies may have particular utility after renal transplantation. However, given the narrow therapeutic window with respect to hypercalcemia and hypercalciuria, and the demonstrated efficacy of bisphosphonates to prevent post-transplantation bone loss, we regard these agents as adjunctive rather than primary therapy for transplantation osteoporosis. The effects of 1,25(OH)(2)D on the immune system, which are still being elucidated, may have potential for reducing infections and preventing allograft rejection after transplantation.

Effect of early risedronate treatment on bone mineral density and bone turnover markers after liver transplantation: a prospective single-center study

The aim of this study was to investigate the effect of risedronate (RIS) on bone loss and bone turnover markers after liver transplantation (LT). Patients with osteopenia or osteoporosis within the first month after LT were randomized to receive RIS 35 mg/week plus calcium 1000 mg/day and vitamin D(3) 800 IU/day (n = 45) or calcium and vitamin D(3) at same dosages (n = 44). Primary endpoint was change in bone mineral density (BMD) 6 and 12 months after LT. Secondary endpoints included changes in serum β-CrossLaps (β-CTX) and procollagen type 1 amino-terminal peptide (P1NP) and fracture rate. Spine X-rays were obtained at baseline and after 12 months. There was no significant difference in BMD changes between both treatment groups at any sites; either at 6 or 12 months. Spine BMD increased in both groups at 12 months vs. baseline (P = 0.001). RIS patients had a significant increase in intertrochanteric BMD at 12 months (P < 0.05 vs. baseline). Serum β-CTX decreased in both groups (P < 0.01), with significant differences between groups at 3 months. No significant difference in vertebral fracture incidence was found. After 12 months, BMD improved at lumbar spine and did not change at hip in both groups. Significant differences between both groups were not found. Other factors (calcium and vitamin D replacement, early prednisone withdrawal) seem to have also positive effects in BMD.

Osteoporosis following organ transplantation: pathogenesis, diagnosis and management

Organ transplantation has become popular for the management of various chronic illnesses. With the advent of modern immunosuppressive treatments, the longevity of transplant recipients has increased. Consequently, morbid complications such as osteoporosis and bone fractures are seen at an increasing frequency in this population. In most transplant recipients, bone mineral density (BMD) falls shortly after transplantation. However, bone fracture rate plateaus in all except for post-renal transplant patients. Although the underlying pathophysiologic mechanism for this difference is not fully understood, potential mechanisms for sustained bone loss in renal transplant recipients may be persistent phosphorus wasting and defective bone mineralization. Current treatment regimens are based on studies in a small numbers of subjects with BMD as the primary outcome. Although BMD is recognized as a gold standard in the assessment of bone fracture risk, to date, its association with bone fracture risk in the general post-transplant population is not robust. Therefore, randomized controlled trials with bone fracture as the primary end point are crucial. The development of noninvasive bone markers in distinguishing bone turnover and bone mineralization status is also pivotal since skeletal lesions are heterogeneous in various organ transplantations. The elucidation of these underlying skeletal lesions is necessary for the consideration of selective treatment in this population.

Liver and bone

Osteoporosis is a frequent complication in patients with chronic liver disease, especially in end-stages and in cases with chronic cholestasis, hemochromatosis and alcohol abuse. The problem is more critical in transplant patients when bone loss is accelerated during the period immediately after transplantation, leading to a greater incidence of fractures. Advanced age, low body mass index and severity of the liver disease are the main risk factors for bone disease in patients with cholestasis. Mechanisms underlying osteoporosis in chronic liver disease are complex and poorly understood, but osteoporosis mainly results from low bone formation, related to the effects of retained substances of cholestasis, such as bilirubin and bile acids, or to the effects of alcohol on osteoblastic cells. Increased bone resorption has also been described in cholestatic women with advanced disease. Although there is no specific treatment, bisphosphonates associated with supplements of calcium and vitamin D are effective for increasing bone mass in patients with chronic cholestasis and after liver transplantation. The outcome in reducing the incidence of fractures has not been adequately demonstrated essentially because of the low number of patients included in the therapeutic trials. Randomized studies assessing bisphosphonates in larger series of patients, the development of new drugs for osteoporosis and the improvement in the management of liver transplant recipients may change the future.

Male hypogonadism in cirrhosis and after liver transplantation

Liver is deeply involved in the metabolism of proteins, hormones, enzymes, cytokines, as well as in sex hormones catabolism. Gonadal function requires a normal liver function, and it is well known that clinical signs of hypogonadism are common in patients with liver cirrhosis. Few studies have focused on hypothalamic- pituitary-gonadal alterations in male cirrhotic patients or after orthotopic liver transplantation (OLT). The pathogenesis of hypogonadism in cirrhotic patients is complex and not well explained. It involves both a gonadal and a hypothalamic- pituitary dysfunction. After OLT the hypothalamic-pituitary-gonadal function partially improves, showing that the hepatic dysfunction before OLT is deeply involved in its pathogenesis. After OLT some alterations persist in some patients, both because of pre-existing gonadal alterations (toxic-metabolic damage) and immunosuppressive pharmacological side effects. Further studies will explain the relationship between hypogonadism and OLT outcome, and the role of androgen therapy in hypogonadism after OLT, in the early months and in the long term.

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.

Bone disorders in chronic liver disease

Osteomalacia rarely occurs in adult patients with chronic liver disease despite a low serum vitamin D level being reported in up to two-thirds of patients with cirrhosis. In contrast, osteoporosis, which increases the risk of vertebral fractures, occurs in 12%-55% of patients with cirrhosis. Although the prevalence is probably falling, as shown by a fall from 57%-26% in patients with biliary disease requiring liver transplantation over the last 2 decades, it still accounts for significant patient morbidity. Bone density also falls in the first 3 months after liver transplantation, and pretransplant fractures are predictive of posttransplant fractures. Many of the known risk factors for postmenopausal osteoporosis exist in the cirrhotic population, such as excess alcohol intake, steroid use, poor nutrition, and hypogonadism. There is also an increased risk of osteoporosis in patients without cirrhosis, particularly those with hemochromatosis and biliary disease. The diagnosis is made with bone density measurements. The effective treatment is largely based on evidence from postmenopausal osteoporosis as there have been only a few small clinical trials of patients with chronic liver disease. Bisphosphonates are the mainstay of treatment; they have been shown to be effective in biliary disease and are well tolerated.

Review article: medical management of the liver transplant recipient - a primer for non-transplant doctors

BACKGROUND

Survival 10 years after orthotopic liver transplantation now approaches 65%. Consequently, community doctors must manage the metabolic and neoplastic complications of orthotopic liver transplantation in an ageing population.

AIMS

To review common sources of morbidity and mortality in long-term orthotopic liver transplantation recipients, and to make evidence-based recommendations regarding their management.

METHODS

Pertinent studies and reviews were identified by literature search through PubMed. Where evidence-based recommendations could not be gleaned from the literature, expert opinion was obtained from syllabi of national meetings.

RESULTS

The two most common causes of morbidity and mortality in orthotopic liver transplantation recipients are atherosclerotic vascular disease and de novo malignancy. The pathogenesis of many complications begins before orthotopic liver transplantation, and many are potentially modifiable. Most complications, however, can be directly ascribed to immunosuppressive agents. Despite improvements in our understanding of the pathogenesis and epidemiology of the metabolic and neoplastic complications of orthotopic liver transplantation, remarkably few randomized-controlled studies exist to define their optimal management.

CONCLUSIONS

Orthotopic liver transplantation recipients experience and succumb to the same afflictions of old age as non-transplant patients, but with greater frequency and at an earlier age. Most recommendations regarding surveillance for, and treatment of, medical complications of orthotopic liver transplantation remain based upon expert opinion rather than evidence-based medicine.

The Prevention of Bone Fractures After Liver Transplantation: Experience With Alendronate Treatment

OBJECTIVE

The aim of this study was to prevent fractures in the first postoperative year.

METHODS AND PATIENTS

We studied 59 patients (48 men, 11 women) aged 42.6+/-11.4 years, who underwent liver transplantation. All patients received oral alendronate 70 mg weekly and calcium 1 g and calcitriol 0.5 mug daily. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry at the lumbar spine and proximal femur at baseline as well as at 6 and 12 months after transplantation for comparison with an historical control group (n=31). Spinal radiographs were obtained to assess vertebral fractures at the same time. Additionally, serum osteocalcin, serum parathyroid hormone (PTH), urinary deoxypyridinoline (DPD), and biochemical parameters were determined every 3 months.

RESULTS

At baseline, femoral total BMD of men was significantly greater than that of women (P<.05, .85+/-.1 vs .74+/-.1). A significant increase in BMD was observed at 12 months (P<.05), no patient developed a bone fracture. Comparison analysis of genders showed that there was a significant difference in favor of men (P<.05). The lumbar BMD, neck T-, and Z-scores were significantly higher among patients treated with alendronate than historical controls (P<.05). After 3 months, serum PTH was increased and serum osteocalcin and urinary DPD were reduced. No severe side effects from alendronate treatment were observed during the study.

CONCLUSION

A direct sign of the success of our study was no fracture observed during the first postoperative year. Alendronate should be considered for patients with low bone mass after liver transplantation.

Management of bone loss after organ transplantation

Organ transplant recipients experience rapid bone loss and high fracture rates, particularly during the early post-transplant period. Early rapid bone loss occurs in the setting of uncoupled bone turnover with increased bone resorption and decreased bone formation. Because there are no clinical factors that reliably predict post-transplant bone loss and fractures in the individual patient, all transplant recipients should be considered candidates for early preventive therapy for osteoporosis. Long-term transplant recipients with densitometric osteoporosis and/or fractures should also receive treatment. Although active metabolites of vitamin D and bisphosphonates have both shown efficacy, data from clinical trials suggest that bisphosphonates are the safest and most consistently effective agents for the prevention and treatment of post-transplantation osteoporosis in adults. Kidney transplant recipients represent a special population, and more research is needed to delineate the risks and benefits of treating bone disease in these patients.

Low bone mineral density in noncholestatic liver cirrhosis: prevalence, severity and prediction

BACKGROUND

Metabolic bone disease has long been associated with cholestatic disorders. However, data in noncholestatic cirrhosis are relatively scant.

AIMS

To determine prevalence and severity of low bone mineral density in noncholestatic cirrhosis and to investigate whether age, gender, etiology, severity of underlying liver disease, and/or laboratory tests are predictive of the diagnosis.

PATIENTS/METHODS

Between March and September/1998, 89 patients with noncholestatic cirrhosis and 20 healthy controls were enrolled in a cross-sectional study. All subjects underwent standard laboratory tests and bone densitometry at lumbar spine and femoral neck by dual X-ray absorptiometry.

RESULTS

Bone mass was significantly reduced at both sites in patients compared to controls. The prevalence of low bone mineral density in noncholestatic cirrhosis, defined by the World Health Organization criteria, was 78% at lumbar spine and 71% at femoral neck. Bone density significantly decreased with age at both sites, especially in patients older than 50 years. Bone density was significantly lower in post-menopausal women patients compared to pre-menopausal and men at both sites. There was no significant difference in bone mineral density among noncholestatic etiologies. Lumbar spine bone density significantly decreased with the progression of liver dysfunction. No biochemical variable was significantly associated with low bone mineral density.

CONCLUSIONS

Low bone mineral density is highly prevalent in patients with noncholestatic cirrhosis. Older patients, post-menopausal women and patients with severe hepatic dysfunction experienced more advanced bone disease. The laboratory tests routinely determined in patients with liver disease did not reliably predict low bone mineral density.

Osteoporosis after liver transplantation

Osteoporosis remains a serious potential complication of liver transplantation, although its incidence may be significantly reduced by the use of lower doses of glucocorticoids. Additional factors likely to contribute to its pathogenesis include other immunosuppressive agents, particularly cyclosporin A and FK506, vitamin D insufficiency, secondary hyperparathyroidism, hypogonadism and pre-existing bone disease. Bone density assessment and spinal X-rays should be performed before transplantation to assess subsequent fracture risk and vitamin D and gonadal status assessed. Measures should be taken to optimise bone health prior to transplantation; in those with low bone mineral density and/or previous fragility fracture, prophylaxis against bone loss after transplantation should be considered. Although anti-fracture efficacy has not been established for any agent there is evidence, mainly in patients undergoing other forms of solid organ transplantation, that repeated infusions of pamidronate may be effective in preventing bone loss.

Secondary Osteoporosis in Liver Transplant Recipients: a Longitudinal Study in Patients With and Without Cholestatic Liver Disease

BACKGROUND

Metabolic bone disease is one of the major long-term complications in liver transplant recipients, but it remains unclear which patients are at highest risk for developing severe bone disease following transplantation.

METHODS

A total of 46 consecutive, adult patients with chronic liver disease accepted for a liver transplantation waiting list were prospectively included in the study. The patients were classified into two groups: group A-chronic cholestatic liver disease (n = 28), and group B-chronic non-cholestatic liver disease (n = 18). Bone mineral density (BMD) was measured at acceptance for the waiting list and at 3, 12 and 36 months following transplantation. Markers of bone turnover (serum-bone specific alkaline phosphatases (bALP), s-osteocalcin, s-l-collagen-C-terminal telopeptide (1-CTP) and urine N-terminal telopeptides u-Ntx) were measured at acceptance and at 3, 6, 12, 24 and 36 months following transplantation. BMD and markers of bone turnover were compared with similar values in a matched control group of 42 healthy individuals.

RESULTS

BMD decreased significantly during the early post-transplantation period (median bone loss femoral neck (FN) 3 months post-transplant 8.5%). BMD levels declined slightly from 3 to 12 months following transplantation and increased thereafter. The relative bone loss was greatest among group B patients (relative bone loss FN 3 months post-transplant: group A, 8% versus group B, 13%; P = 0.04). At 36 months, 8/17 group A and 2/9 group B patients had BMD levels that exceeded the pretransplant levels (P = 0.12). The early bone loss was positively correlated with an increase in resorption markers (s-1-CTP and u-Ntx). Group B had higher levels of both s-1-CTP and u-Ntx at 3 and 6 months post-transplant than group A patients (P = 0.03). Bone formation markers increased slowly from 6 months post-transplant and onwards. Relative bone loss was positively correlated to total glucocorticoid dose during the first 3 months post-transplant. There were no differences in BMD between patients receiving tacrolimus versus those receiving'cyclosporin A.

CONCLUSION

Bone loss following liver transplantation is considerable in patients with both cholestatic and non-cholestatic liver disease, the first group has the poorest starting-point while the latter group has the greatest bone loss following transplantation. Bone loss is closely correlated with biochemical markers of bone resorption and total dose of glucocorticoids given post-transplant.