Hepatic osteodystrophy: An important matter for consideration in chronic liver disease

Hepatic osteodystrophy (HO) is the generic term defining the group of alterations in bone mineral metabolism found in patients with chronic liver disease. This paper is a global review of HO and its main pathophysiological, epidemiological and therapeutic aspects. Studies examining the most relevant information concerning the prevalence, etiological factors, diagnostic and therapeutic aspects involved in HO were identified by a systematic literature search of the PubMed database. HO generically defines overall alterations in bone mineral density (BMD) (osteoporosis or osteopenia) which appear as a possible complication of chronic liver disease. The origin of HO is multifactorial and its etiology and severity vary in accordance with the underlying liver disease. Its exact prevalence is unknown, but different studies estimate that it could affect from 20% to 50% of patients. The reported mean prevalence of osteoporosis ranges from 13%-60% in chronic cholestasis to 20% in chronic viral hepatitis and 55% in viral cirrhosis. Alcoholic liver disease is not always related to osteo-penia. HO has been commonly studied in chronic cholestatic disease (primary biliary cirrhosis and primary sclerosing cholangitis). Several risk factors and pathogenic mechanisms have been associated with the loss of BMD in patients with chronic liver disease. However, little information has been discovered in relationship to most of these mechanisms. Screening for osteopenia and osteoporosis is recommended in advanced chronic liver disease. There is a lack of randomized studies assessing specific management for HO.     

Bone health and vitamin D status in alcoholic liver disease

Alcohol consumption is harmful to many organs and tissues, including bones, and it leads to osteoporosis. Hepatic osteodystrophy is abnormal bone metabolism that has been defined in patients with chronic liver disease (CLD), including osteopenia, osteoporosis, and osteomalacia. Decreased bone density in patients with CLD results from decreased bone formation or increased bone resorption. The prevalence of osteopenia in alcoholic liver disease (ALD) patients is between 34 % and 48 %, and the prevalence of osteoporosis is between 11 % and 36 %. Cirrhosis is also a risk factor for osteoporosis. The liver has an important role in vitamin D metabolism. Ninety percent of patients with alcoholic liver cirrhosis have vitamin D inadequacy (<80 nmol/L). The lowest serum vitamin D levels were observed in patients with Child–Pugh class C. Bone densitometry is used for the definitive diagnosis of osteoporosis in ALD. There are no specific controlled clinical studies on the treatment of osteoporosis in patients with ALD. Alcohol cessation and abstinence are principal for the prevention and treatment of osteoporosis in ALD patients, and the progression of osteopenia can be stopped in this way. Calcium and vitamin D supplementation is recommended, and associated nutritional deficiencies should also be corrected. The treatment recommendations of osteoporosis in CLD tend to be extended to ALD. Bisphosphonates have been proven to be effective in increasing bone mineral density (BMD) in chronic cholestatic disease and post-transplant patients, and they can be used in ALD patients. Randomized studies assessing the management of CLD-associated osteoporosis and the development of new drugs for osteoporosis may change the future. Here, we will discuss bone quality, vitamin D status, mechanism of bone effects, and diagnosis and treatment of osteoporosis in ALD.     

Predicting bone loss following orthotopic liver transplantation

BACKGROUND: Hepatic osteodystrophy occurs in the majority of patients with advanced chronic liver disease with the abnormalities in bone metabolism accelerating following orthotopic liver transplantation (OLT). AIMS: To examine changes in bone mineral density (BMD) following OLT and to investigate factors that lead to bone loss. METHODS: Twelve patients had BMD (at both the lumbar spine (LS) and femoral neck (FN)) and biochemical markers measured preoperatively and for 24 months following OLT. RESULTS: BMD was low in 75% of patients prior to OLT and decreased significantly from baseline at the LS at three months and the FN at six months. BMD began to increase thereafter at both sites, approaching baseline values at the LS by 12 months. Bone formation markers, osteocalcin and procollagen type I carboxy propeptide, decreased immediately post-OLT, with a concomitant increase seen in the resorption markers pyridinoline and deoxypyridinoline. This resulted in a negative uncoupling index early post-OLT, that rebounded to positive values after six months. There was a significant correlation between the change in the uncoupling index between six and three months which preceded the increase in BMD at 12 months. The decrease in BMD recorded early post-OLT correlated with vitamin D levels at three months. CONCLUSIONS: Results suggest that increased resorption and inadequate formation are the major contributors to additional bone loss following OLT. Non-invasive biochemical markers precede later changes in BMD in this patient group following OLT and may have a role in investigating and planning intervention strategies to prevent bone loss in future studies.     

Pamidronate and osteoporosis prevention in liver transplant recipients

Osteoporosis is a common complication in patients with end-stage liver disease and after orthotopic liver transplantation (LT), with resulting increasing fracture rate. In this study, we investigated the role of treatment with pamidronate in preventing further bone loss after LT. Eighty-five patients with end-stage liver disease were included in the study. Pamidronate 30 mg was given intravenously every 3 months after LT for the duration of 1 year to 43 patients with osteopenia or osteoporosis prior LT. The remainders served as controls. All patients received a supplementation of calcium and vitamin D. Bone mineral density (BMD) at the lumbar spine and the femoral neck, and markers of bone metabolism were measured before and 12 months after LT. Sixty-two BMD were available at 12 months; only paired BMD were evaluated. A significant increase in lumbar spine BMD was observed in pamidronate treated patients. No change was evident in controls. Femoral neck BMD decreased in both treated and untreated patients. Osteocalcin serum levels and deoxypyridinoline urinary excretion were significantly reduced by treatment. Our study suggests that pamidronate decreases bone turnover and is effective in preventing the course of bone loss after LT, however the efficacy, at the dosage regimen employed and in a follow-up of 12 months, appears to be limited to trabecular bone, with no effect on the cortical structure of the femur.     

Treatment of bone disease in chronic kidney disease and in renal transplant recipients under K/DOQI clinical practice guidelines

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (K/DOQI) provides evidence based clinical practice guidelines developed for all phases of kidney disease and related complications, from diagnosis to monitoring and management. Bone disease sets in during the early stages of Chronic Kidney Disease (CKD). Bone disease is observed in almost patients with chronic renal failure and after renal transplantation. Hyperparathyroid (high turnover) bone disease in patients with chronic renal failure is found most frequently followed by mixed osteodystrophy, low-turn over bone disease, and osteomalasia. Ninety to one hundred percent of kidney transplant patients have histological evidence of osteodystrophy and osteopenia (reduction of bone mass) following renal transplantation. Furthermore, osteoporosis is also appeared in many renal transplant recipients. After renal transplantation, renal osteodystrophy generally improves but bone mineral density (BMD) often worsens. When renal bone disease is assessed using a combination of biochemical markers, histology and bone densitometry, early intervention and carefully effective therapies might be reduced the morbidity associated with these common problems.     

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-1-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.     

Vitamin D-receptor genotypes as independent genetic predictors of decreased bone mineral density in primary biliary cirrhosis

BACKGROUND & AIMS: Hepatic osteodystrophy is a complication of primary biliary cirrhosis (PBC). Allelic polymorphisms of the vitamin D receptor (VDR) gene are related to bone mineral density (BMD) in normal cohorts and those with primary osteoporosis. We sought to establish the prevalence of reduced bone mass in PBC, correlate BMD with VDR gene polymorphisms, and identify risk factors for the development of hepatic osteodystrophy. METHODS: Seventy-two female patients with PBC were evaluated prospectively. Clinical information, BMD assessment, disease severity, and osteoporosis risk factors were documented, and multivariate regression modeling was performed. RESULTS: Twenty-four percent of the patients were osteoporotic at the lumbar spine and 32% at the femur. Severe bone loss (z score <-2.0) occurs 4 times more frequently in patients with PBC compared with controls. Body weight (P = 0.003) and postmenopausal status (P = 0.012) correlated independently with BMD. VDR genotype (P = 0.01) correlated with lower BMD at the spine only. CONCLUSIONS: Osteoporosis is a common complication of PBC. VDR genotype predicts lower BMD in patients with PBC. Studies are warranted to investigate the mechanism(s) by which VDR as well as other candidate genes may contribute to the development of hepatic osteodystrophy in PBC.     

Severity of liver disease does not predict osteopenia or low bone mineral density in primary sclerosing cholangitis.

BACKGROUND: The association between metabolic bone disease and cholestatic liver disease has been poorly characterized. To date a single institution has published data suggesting that in primary sclerosing cholangitis (PSC), advanced liver disease predicts advanced bone disease. Aim: To determine the association between the severity of liver disease and bone mineral density (BMD) in PSC patients. METHODS: We identified 30 PSC patients who had undergone dual energy X-ray absorptiometry (DXA) scan. We compared lumbar spine DXA scores between patients with more and less advanced liver disease. RESULTS: Nine patients were osteopenic (30%), and one patient was osteoporotic. Five patients were female (17%), and none was postmenopausal. BMD was not different between patients listed and not listed for liver transplantation (P = 0.49) or between patients with and without hepatic decompensation (P = 0.63). Model for end-stage liver disease (MELD) score (P = 0.99) and the modified Mayo risk score (P = 0.25) did not predict BMD. CONCLUSIONS: Our study is the first to suggest that low bone density cannot be predicted by the severity of liver disease in PSC. Perhaps other known risk factors for osteoporosis will be important predictors of abnormal bone density in this patient population.     

Regional bone mineral density after orthotopic liver transplantation

OBJECTIVES: Although there is a fall in lumbar spine bone mineral density (BMD) after liver transplantation, little is known about femoral neck or total body BMD. Therefore we determined: (a) the proportion of patients with preexisting hepatic osteopenia before transplantation and (b) the effects of transplantation on global and regional BMD. DESIGN: Retrospective analysis of BMD measurements of patients before and up to 2 years after liver transplantation. METHODS: BMD was assessed by dual energy X-ray absorptiometry in 56 patients, before and at regular intervals after liver transplantation, for up to 24 months, to measure total body, lumbar spine (L2-L4) and femoral neck BMDs. RESULTS: Pre-transplant, 23% of patients had osteoporosis (a negative Z score > 2). Paired data before and after transplantation revealed no change in total body BMD. However, there was a fall in lumbar spine BMD (1.04+/-0.03 to 1.02+/-0.03 g/cm2; P < 0.04) at 1 month after transplantation. The reduction in lumbar spine BMD was seen up to 12 months, BMD at 18-24 months being similar to pre-transplant values. Femoral neck BMD also fell (0.96+/-0.06 to 0.83+/-0.04 g/cm2; P < 0.03), but only after 6-9 months, thereafter remaining below pre-transplant values until the end of the follow-up period. CONCLUSIONS: Although osteopenia is common in patients with liver disease, total bone density does not fall after transplantation. Nonetheless regional lumbar spine and femoral neck bone density does fall after transplantation with a risk period for femoral neck fracture which may extend for up to 2 years.     

MELD score, insulin-like growth factor 1 and cytokines on bone density in end-stage liver disease

AIM:To determine the contributions of insulin-like growth factor 1 (IGF-1),cytokines and liver disease severity to bone mineral density in patients pre-transplantation.METHODS:Serum IGF-1,tumor necrosis factor-α (TNFα) and interleukin 6 (IL-6) were measured and the Model for End-Stage Liver Disease (MELD) score calculated in 121 adult patients referred to a single centre for liver transplantation.Bone mineral density (BMD) of the lumbar spine and femoral neck were assessed via dual energy X-ray absorptiometry.Demographics,liver disease etiology,medication use and relevant biochemistry were recorded.RESULTS:A total of 117 subjects were included,with low BMD seen in 68.6%,irrespective of disease etiol-ogy.In multivariable analysis,low body mass index (BMI),increased bone turnover and low IGF-1 were independent predictors of low spinal bone density.At the hip,BMI,IGF-1 and vitamin D status were predictive.Despite prevalent elevations of TNFα and IL-6,levels did not correlate with degree of bone loss.The MELD score failed to predict low BMD in this pre-transplant population.CONCLUSION:Osteopenia/osteoporosis is common in advanced liver disease.Low serum IGF-1 is weakly predictive but serum cytokine and MELD score fail to predict the severity of bone disease.     

Osteoporosis after solid organs transplantation

Osteoporosis is a common complication following kidney, heart, liver and lung transplantation. Immunosuppressive regimens to prevent graft rejection after transplantation commonly include glucocorticoids, cyclosporin A and tacrolimus which are detrimental to bone and mineral homeostasis and are superimposed on an already compromised skeleton. Additional factors likely to contribute to post-transplantation osteoporosis pathogenesis are vitamin D insufficiency, secondary hyperparathyroidism and hypogonadism. Measures should be taken to optimize bone health prior transplantation: bone mineral density and spinal X-rays should be performed, and vitamin D and gonadal status assessed. Prophylaxis against bone loss after transplantation should be considered for all patients. Data from clinical trials suggest that bisphosphonates are the most promising agents for the prevention and treatment of post-transplantation osteoporosis.     

肝移植后骨质疏松症的研究进展

肝移植后骨质疏松症及其直接导致的骨质疏松性骨折严重影响了移植患者的生存质量。多数终末期肝病患者由于钙、磷代谢紊乱,性腺功能减退,继发性甲状旁腺功能亢进及细胞因子的作用,在移植前就存在骨量减少;而移植后的快速骨量丢失主要与糖皮质激素的应用、遗传因素及手术相关因素有关。密切随访、及时有效的药物治疗对于防治肝移植后骨质疏松症具有积极意义。     

Primary biliary cirrhosis is not an additional risk factor for bone loss in women receiving regular calcium and vitamin D supplementation: a controlled longitudinal study

BACKGROUND AND GOALS: Alterations in bone metabolism in primary biliary cirrhosis (PBC) are generally considered to be highly prevalent and severe, but no data are available from prospective studies with adequate control groups. The aims of this study were: (1) to measure changes in bone mineral density (BMD) over time; (2) to correlate the degree of bone loss with the severity of liver disease; and (3) to characterize bone disease in PBC patients receiving regular calcium and vitamin D supplementation. STUDY: We enrolled 118 women with PBC (mean age+/-SD: 56+/-11 y; 72% postmenopausal; 43% with cirrhosis), and measured BMD (lumbar spine, DXA-Hologic) at entry and serially over the following 5 years. The controls were 472 healthy women selected from a large observational group matched for age and menopausal status (mean age+/-SD: 55+/-10 y; 73% postmenopausal). RESULTS: Mean BMD was 0.851+/-0.142 g/cm2 in the PBC group and 0.857+/-0.158 g/cm2 in the control group; the prevalence of osteoporosis was 28% and 29%, respectively. BMD significantly correlated with age and postmenopausal status, but not with liver cirrhosis or serum bilirubin levels. The biochemical markers of bone turnover were high in about 50% of the patients. The yearly bone loss in the PBC group was 0.008 g/cm2 (95% confidence interval: 0.014-0.003) similar to that calculated in the control group. CONCLUSIONS: Among patients with PBC, the prevalence of osteoporosis and the yearly rate of BMD loss are similar to those observed in the general population, and are not associated with the severity of liver disease.     

Management of osteoporosis in primary biliary cirrhosis.

Osteoporosis is not a significant problem in the majority of patients with primary biliary cirrhosis (PBC). However, substantial bone-related morbidity may occur in patients with advanced disease, in particular after liver transplantation. The cause of osteoporosis in PBC is multifactorial, and pathophysiological mechanisms specifically related to PBC have not been defined. In general, the principles of management followed in post-menopausal osteoporosis also apply in chronic liver disease. Dual energy X-ray absorptiometry is currently the method of choice for monitoring bone mineral density. Avoidance of conditions with potential negative effects on bone mass, and maintaining adequate serum vitamin D levels and calcium intake form the cornerstone in preventing osteoporosis. Bisphosphonates are the most logical choice when specific medical treatment of PBC-associated osteoporosis is indicated, as well as for preventing bone loss during glucocorticoid treatment and after liver transplantation. Recent studies suggest that active vitamin D analogues are effective alternatives in the post-transplant setting.     

Lack of effect of intravenous pamidronate on fracture incidence and bone mineral density after orthotopic liver transplantation

BACKGROUND/AIMS: Increased rates of bone loss and fracture have been reported after liver transplantation. The aim of this study was to investigate the effects of a pre-transplant infusion of pamidronate on fracture incidence and bone loss during the first year after transplantation. METHODS: Ninety-nine adults awaiting orthotopic liver transplantation (OLT) were randomised to pamidronate or no treatment. Spinal X-rays were obtained at baseline and after 12 months. Bone mineral density (BMD) was measured at the lumbar spine (L1-4) and femoral neck at baseline, and 3, 6, and 12 months after OLT. RESULTS: The incidence of fractures in the first year after OLT was 8%, four patients within the pamidronate treated group and two in the untreated group developing fractures (P=0.40). No significant spinal bone loss occurred in either group during the first year. However, significant and sustained bone loss occurred at the femoral neck in both groups. No significant differences were seen between pamidronate treated or untreated groups at either site. CONCLUSIONS: Pamidronate in the regimen used had no significant effect on fracture rate or BMD post-transplant. The low incidence of fracture and absence of spinal bone loss indicate that bone disease after liver transplantation may be less common than previously reported.     

乙型肝炎肝硬化肝性骨营养不良的临床研究

目的探讨乙型肝炎肝硬化与肝性骨营养不良和骨质疏松的关系。方法收集自2008年3月~2009年3月在我院住院的乙型肝炎肝硬化患者43例,健康对照组21例,采用双能X线骨密度仪测定股骨颈、尺桡骨骨密度,空腹抽血测定血钙、血磷、甲状旁腺素、降钙素、白细胞介素-6。结果肝硬化组骨质疏松发生率显著高于对照组（P=0.003）;两组股骨颈骨密度[（-0.860±0.705）g/cm2vs（0.125±0.715）g/cm2,P〈0.001]、尺桡骨骨密度[（-0.702±0.666）g/cm2vs（0.279±0.709）g/cm2,P〈0.001）]、血钙[（2.151±0.168）mmol/Lvs（2.336±0.170）mmol/L,P〈0.001）]比较,肝硬化组显著低于对照组;血磷[（1.051±0.077）mmol/Lvs（0.961±0.069）mmol/L,P〈0.001）]、甲状旁腺素[（412.674±22.779）ng/Lvs（386.000±30.223）ng/L,P〈0.001）]、降钙素[（45.358±3.900）pg/Lvs（30.667±3.120）pg/L,P〈0.001）]、IL-6[（41.795±14.988）pg/mlvs（4.077±1.555）pg/mL,P〈0.001]比较,肝硬化组显著高于对照组;肝硬化组股骨颈骨密度与IL-6呈负相关。结论肝性骨营养不良是乙型肝炎肝硬化严重并发症之一,以骨质疏松为常见表现,应监测骨密度预防肝性骨营养不良。     

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.     

Skeletal morbidity in inflammatory bowel disease

Patients with Crohn's disease are at increased risk of developing disturbances in bone and mineral metabolism because of several factors, including the cytokine-mediated nature of the inflammatory bowel disease, the intestinal malabsorption resulting from disease activity or from extensive intestinal resection and the use of glucucorticoids to control disease activity. Inability to achieve peak bone mass when the disease starts in childhood, malnutrition, immobilization, low BMI, smoking and hypogonadism may also play a contributing role in the pathogenesis of bone loss. The relationship between long-term use of glucocorticoids for any disease indication and increased risk for osteoporosis and fractures is well established. However, the relationship between Crohn's disease and ulcerative colitis and bone loss remains controversial. Depending on the population studied the prevalence of osteoporosis has thus been variably reported to range from 12 to 42% in patients with inflammatory bowel disease (IBD). In IBD most studies demonstrate a negative correlation between bone mineral density (BMD) and glucocorticoid use, but not all authors agree on the relationship between long-term glucocorticoid use and continuing bone loss. Whereas prospective studies do suggest sustained bone loss at both trabecular and cortical sites in long-term glucocorticoid users with inflammatory bowel disease, a decrease in bone mass is also observed in patients with active Crohn's disease not using glucocorticoids, and bone loss is not universally observed in patients with Crohn's disease using orally or rectally administered glucocorticoids. Data on vertebral fractures are scarce and there is no agreement about the risk of non-vertebral fractures in patients with Crohn's disease, although it has been suggested that non-vertebral fracture risk may be increased by up to 60% in patients with IBD. A recent publication reports an increased risk of hip fractures in Crohn's disease related to current and cumulative corticosteroid use and use of opiates, although these fractures could not be related to the severity of osteoporosis. The issue of the magnitude of the problem of osteoporosis has become particularly relevant in Crohn's disease, since the ability of therapeutic interventions to beneficially influence skeletal morbidity has been clearly established in patients with osteoporosis, whether post-menopausal women, men or glucocorticoid users. The main question that arises is whether all patients with Crohn's disease should be treated with bone protective agents on the assumption that they all have the potential to develop osteoporosis or whether the use of these agents should be restricted to patients clearly at risk of osteoporosis and fractures, providing these can be identified. We recommend, based on the available literature and our own experience, that all patients with Crohn's disease should be screened for osteoporosis by means of a bone mineral density measurement in addition to full correction of any potential calcium and vitamin D deficiency, to allow timely therapeutic intervention of the patient at risk while sparing the vast majority unnecessary medical treatment.     

慢性肝病患者骨代谢变化的临床意义

为探讨慢性乙型肝炎（下称慢乙肝），乙肝肝硬化（下称肝硬化）与骨代谢的关系，分别对32例慢乙肝，32例肝硬化和31例对照组患者进行了骨钙素（BGP），甲状旁腺激素M（PTHM），血钙，血磷及尺桡骨骨密度（BMD）检测。结果显示，肝硬化组血清BGP水平较肝炎组和对照组明显降低（P＜0．05，＜0．01），血清PTHM水平较肝炎组及对照组升高（P＜0．05，＜0．05），两肝病组血钙水平较对照组明显下降（P均＜0．001），BMD较对照组降低（P＜0．001，＜0．01）；肝硬化组和肝炎组BGP均与BMD呈正相关。提示慢性病毒性肝病可出现调钙激素异常变化，且其骨质疏松随肝病加重而呈加重趋势。     

Osteodystrophy in patients with chronic hepatitis and liver cirrhosis

Bone mineral density (BMD) of the lumber vertebrae and factors related to bone metabolism were determined in patients with chronic viral hepatitis and patients with liver cirrhosis to clarify correlations between hepatic dysfunction, considered to be one of the causes of hepatic osteodystrophy, and decrease in bone mass. BMD of the second to fourth lumbar vertebrae was determined with a Lunar (Madison, WI, USA) DPX, a dual-energy X-ray absorptiometry diagnostic system. BMD was significantly lowest in patients with liver cirrhosis, followed by patients with chronic hepatitis, and healthy subjects, in this order. There was a significantly positive but weak correlation between albumin and BMD. Levels of 25(OH)D and 1,25(OH)₂D were significantly lower in patients with liver cirrhosis than in those with chronic hepatitis. BMD and vitamin D were decreased in all patients whose cholinesterase (ChE) was below 0.3ΔpH. Urinary pyridinoline(Upyr) was significantly higher in the patients with liver cirrhosis, in whom bone mass was decreased, than in the patients with chronic hepatitis, whereas serum osteocalcin levels were distributed in the upper normal range in patients with chronic hepatitis and those with liver cirrhosis. There was a positive correlation between 25(OH)D and serum osteocalcin levels in patients with liver cirrhosis. These results indicate that osteogenesis is decreased and suggest that the decrease in BMD which occurs in viral liver cirrhosis, probably related to decreased, bone formation and slight promotion of bone resorption, reflects deranged hepatic function. This is the first report of Upyr and urinary deoxypyridinoline (UDpyr) determination in patients with liver cirrhosis and patients with chronic hepatitis. The negative correlation of Upyr and UDpyr with ChE is a novel finding.