Osteoporosis in primary biliary cirrhosis revisited

Extrahepatic manifestations of cholestatic liver diseases: pathogenesis and therapy

Pruritus, fatigue, and metabolic bone disease are frequent complications of cholestatic liver diseases, which can be quite distressing for the patient and can considerably reduce the quality of life. The molecular pathogenesis of these extrahepatic manifestations of cholestasis is poorly understood, and hypotheses to explain these symptoms are being discussed. This article provides treatment recommendations for the complications of cholestasis based on putative pathomechanisms and summarizes recent experimental and clinical data involving management options.

Extrahepatic manifestations of cholestatic liver diseases: pathogenesis and therapy

Pruritus, fatigue, and metabolic bone disease are frequent complications of cholestatic liver diseases, which can be quite distressing for the patient and can considerably reduce the quality of life. The molecular pathogenesis of these extrahepatic manifestations of cholestasis is poorly understood, and hypotheses to explain these symptoms are being discussed. This article provides treatment recommendations for the complications of cholestasis based on putative pathomechanisms and summarizes recent experimental and clinical data involving management options.

Osteoporosis in children and adolescents: etiology and management

Bone mass increases progressively during childhood, but mainly during adolescence when approximately 40% of total bone mass is accumulated. Peak bone mass is reached in late adolescence, and is a well recognised risk factor for osteoporosis later in life. Thus, increasing peak bone mass can prevent osteoporosis. The critical interpretation of bone mass measurements is a crucial factor for the diagnosis of osteopenia/osteoporosis in children and adolescents. To date, there are insufficient data to formally define osteopenia/osteoporosis in this patient group, and the guidelines used for adult patients are not applicable. In males and females aged <20 years the terminology 'low bone density for chronologic age' may be used if the Z-score is less than -2. For children and adolescents, this terminology is more appropriate than osteopenia/osteoporosis. Moreover, the T-score should not be used in children and adolescents. Many disorders, by various mechanisms, may affect the acquisition of bone mass during childhood and adolescence. Indeed, the number of disorders that have been identified as affecting bone mass in this age group is increasing as a consequence of the wide use of bone mass measurements. The increased survival of children and adolescents with chronic diseases or malignancies, as well as the use of some treatment regimens has resulted in an increase in the incidence of reduced bone mass in this age group. Experience in treating the various disorders associated with osteoporosis in childhood is limited at present. The first approach to osteoporosis management in children and adolescents should be aimed at treating the underlying disease. The use of bisphosphonates in children and adolescents with osteoporosis is increasing and their positive effect in improving bone mineral density is encouraging. Osteoporosis prevention is a key factor and it should begin in childhood. Pediatricians should have a fundamental role in the prevention of osteoporosis, suggesting strategies to achieve an optimal peak bone mass.

Hyperbilirubinemia is not a major contributing factor to altered bone mineral density in patients with chronic liver disease

Reduced bone density is commonly encountered in patients with chronic liver disease. Prior studies have shown that unconjugated bilirubin inhibits osteoblast activity and function in vitro and in animal models of bone mineralization. To determine whether hyperbilirubinemia promotes the development of hepatic osteodystrophy, bone mineral density (BMD) was measured by dual energy X-ray absorptiometry in a cohort of 86 consecutive patients with chronic liver disease referred for liver transplant evaluation. The mean age of the study population was 52 years (range, 22-73), in which 52% were female and 90% were white. Average bone density values were significantly lower than expected for age, race, and sex, with Z-scores for the femoral neck and spine of -0.50 (95% confidence interval [CI] -0.63 to -0.37; p=0.0003) and -0.69 (95% CI -0.85 to -0.52; p=0.0001), respectively. Sixty-one subjects (71%) exhibited reduced BMD (T-score of femoral neck or spine<or=-1 standard deviation [SD] below the young-adult mean), and 18 subjects (21%) met criteria for osteoporosis (T-score<-2.5 SD). Stepwise logistic regression analyses identified significant associations between BMD and serum creatinine, alkaline phosphatase, age, and gender. On the other hand, neither unconjugated, nor conjugated, nor total serum bilirubin levels were found to predict diminished BMD. The lack of association between serum unconjugated bilirubin levels and bone mineralization was validated in hyperbilirubinemic Gunn rats, in which BMD and serum osteocalcin levels were no different than in wild-type rodents. In conclusion, the finding that serum bilirubin levels do not correlate with reduced BMD in patients with end-stage liver disease, and that chronic unconjugated hyperbilirubinemia does not lead to alterations in bone mineralization in Gunn rats, suggests that bilirubin is not a major contributing factor to hepatic osteodystrophy.

Evaluation and management of osteoporosis in liver disease

This article discusses the clinical importance of hepatic osteopenia, the identification of risk factors for the individual patient, and the selection of patients, timing, and methods for diagnostic screening. General supportive measures to maximize bone health should be used in all patients at risk. In addition, for the patient with established osteoporosis, specific therapeutic measures may be justified, despite the lack of adequate randomized trials of these agents in patients with hepatic osteopenia.

Is osteoporosis a peculiar association with primary biliary cirrhosis?

AIM

(1) To compare the prevalence of osteoporosis (t-score < or =-2.5 SD) between stage IV PBC patients, and two groups of age- and sex-matched controls: one with hepatitis C virus (HCV)-related cirrhosis, and the other one consisting of a group of healthy subjects from the general population; (2) to identify the main risk factors for the development of bone loss.

METHODS

Thirty-five stage IV PBC patients (mean age 52.5+/-10 years), 49 females with HCV-related cirrhosis (mean age 52.9+/-5.8 years) and 33 healthy females (mean age 51.8+/-2.22 years) were enrolled in the study. Bone metabolism was evaluated by measuring serum calcium corrected for serum albumin (Ca corr.), 25-hydroxy vitamin D (25-OH vit D), parathyroid hormone, osteocalcin. Bone mineral density (BMD) was assessed at the lumbar spine by dual-photon X-ray absorptiometry.

RESULTS

Osteoporosis was present in 5/35 PBC patients (14.2%) and in 7/49 HCV-related cirrhotic patients (14.3%), without any statistical difference between the two groups. Among healthy control subjects, none had osteoporosis. No difference was found between the three groups in serum parameters of bone metabolism. Univariate analysis showed that menopausal state and low BMI were significantly correlated with osteoporosis. Multivariate regression analysis showed that menopausal status, BMI <23, and old age were independent variables significantly correlated with osteoporosis.

CONCLUSION

PBC in itself has no negative influence on BMD. End-stage liver disease patients carry a disease-specific risk for osteoporosis, but have an effective risk of bone loss in relation to individual potential risk for each patient. A practical message should be taken into account, that is, every effort should be made to prevent osteoporosis when a patient has simple osteopenia, or if it is a woman in or near menopausal age.

Glucocorticosteroids for primary biliary cirrhosis

BACKGROUND

Primary biliary cirrhosis is a chronic progressive cholestatic liver disease of presumed autoimmune etiology, characterised by the destruction of small intrahepatic bile ducts and the eventual development of cirrhosis and liver failure. Its progression may be influenced by immunosuppression. Glucocorticosteroids are potent immunosuppressive agents, but they are associated with significant adverse effects, including osteoporosis.

OBJECTIVES

To systematically evaluate the beneficial and harmful effects of glucocorticosteroids versus placebo or no intervention for patients with primary biliary cirrhosis.

SEARCH STRATEGY

The Cochrane Hepato-Biliary Controlled Trials Register,The Cochrane Library, MEDLINE, EMBASE, and the full text of the identified studies were searched until June 2004. The search strategy included terms for primary biliary cirrhosis and glucocorticosteroids (including the names of frequently used preparations). Previous research groups and manufacturers were contacted for additional references. No language restrictions were applied.

SELECTION CRITERIA

Double-blind, single-blind, or unblinded randomised clinical trials evaluating any preparation of glucocorticosteroids versus placebo or no intervention in patients with primary biliary cirrhosis diagnosed by abnormal liver function tests and either anti-mitochondrial antibodies or histology were included. Additional agents were allowed if they were administered to both groups equally.

DATA COLLECTION AND ANALYSIS

The quality of the randomised clinical trials was evaluated by methodology components (generation of allocation sequence; allocation concealment; blinding; follow up). Analyses were performed according to the intention-to-treat method with missing data being accounted for by imputation.

MAIN RESULTS

Only two underpowered trials (reporting 36 and 40 patients) were identified. These differed markedly in their inclusion criteria and treatment protocols. Both stated that they used placebo. However, allocation concealment was unclear. Only one trial reported any patient deaths. No significant improvement in mortality was identified (odds ratio (OR) 0.42, 95% confidence interval (CI) 0.10 to 1.76). Improvements in serum markers of liver inflammation and liver histology were identified. Potentially prognostically linked markers such as bilirubin and albumin were incompletely reported. Bone mineral density (weighted mean difference -2.84%, 95% CI -4.16 to -1.53) and the number of patients with any adverse event (OR 8.99, 95% CI 2.15 to 37.58) were significantly increased in the glucocorticosteroid group.

AUTHORS' CONCLUSIONS

There is insufficient data to support or reject the use of glucocorticosteroids for patients with primary biliary cirrhosis. It may be appropriate to consider a large prospective randomised clinical trial on this topic.

Severity of cholestasis and advanced histological stage but not menopausal status are the major risk factors for osteoporosis in primary biliary cirrhosis

BACKGROUND

Since primary biliary cirrhosis (PBC) is usually diagnosed in postmenopausal women with minor cholestasis, it has been questioned whether PBC itself represents a further risk for osteoporosis.

AIM

To assess the prevalence and risk factors for osteoporosis in an unselected series of women with PBC.

PATIENTS AND METHODS

142 women with PBC (age: 54.3+/-0.8 years) and an age-matched control group. Osteoporosis was established by densitometry (bone mineral density below -2.5 T-score). Age, duration and severity of PBC, body mass index, menopausal status, histological stage and markers of bone turnover were assessed.

RESULTS

Prevalence of osteoporosis was higher in PBC (32.4%) than in normal women (11. 1%) (RR: 3.83, 95%CI: 2.59-5.67, P<0.001). Osteoporosis was associated with older age, menopausal status, body mass index, longer PBC duration, advanced histological stage, high bilirubin and alkaline phosphatase, and low albumin and prothrombin index. Regression analysis identified older age, higher Mayo risk score, lower body mass index and advanced histological stage but not menopause as the independent risk factors for osteoporosis.

CONCLUSIONS

Osteoporosis is more prevalent in women with PBC than in the general population. Age and severity of the disease, but not menopausal status, are the main risk factors for osteoporosis in this liver disease.

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.

Bone disease in primary biliary cirrhosis: lack of association with distal renal tubular acidosis

BACKGROUND AND AIMS

Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.

METHODS

The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.

RESULTS

Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.

CONCLUSIONS

The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.

Fracture risk of women with primary biliary cirrhosis: no increase compared with general population controls

AIM

Patients with primary biliary cirrhosis may be at increased risk of osteoporosis but to what extent this is reflected in an increased fracture risk is unknown. We have enquired about the fracture experience of female primary biliary cirrhosis patients compared with sex- and age-matched controls.

METHODS

Patients aged 30-75 with primary biliary cirrhosis and age-matched controls were sent a postal questionnaire asking about their fracture history and details of risk factors for osteoporosis.

RESULTS

85 eligible patients with primary biliary cirrhosis and 116 controls responded. Forty-one per cent of patients with primary biliary cirrhosis and 30% of controls reported ever having had a fracture odds ratio 1.5 (95% confidence interval: 0.80-2.89). Twenty-eight per cent of primary biliary cirrhosis patients and 23.3% of controls reported a fracture after the age of 30, odds ratio 1.2 (95% confidence interval: 0.57-2.56), and 14.1% of primary biliary cirrhosis patients and 12.1% of controls reported a low impact fracture of the long bones or of the vertebrae odds ratio 1.0 (95% confidence interval: 0.31-2.68).

CONCLUSIONS

No overall increased fracture risk in patients with primary biliary cirrhosis was observed. As a group, unselected patients with primary biliary cirrhosis do not represent a population at particularly high risk of osteoporotic fracture and thus targeting them for osteoporosis screening and treatment is not justified. Further work investigating subgroups of patients with primary biliary cirrhosis at potentially high risk of osteoporosis, such as those with advanced disease or severe cholestasis is required.

Distúrbios do eixo cálcio-PTH-vitamina D nas doenças hepáticas crônicas

Distúrbios no eixo cálcio-PTH-vitamina D são freqüentemente associados às doenças hepáticas crônicas (DHC). Já foi demonstrado que pacientes com DHC apresentam uma tendência à diminuição do cálcio e vitamina D, com aumento compensatório do PTH. Embora a diminuição da hidroxilação da vitamina D em 25 (OH) vitamina D fosse considerada o mecanismo principal destas alterações, estudos recentes vêm demonstrando que, mesmo nos estágios avançados de doença, o fígado ainda consegue manter níveis adequados de 25 (OH) vitamina D. Desta forma, outros fatores (ex: dieta inadequada, diminuição da exposição à luz solar) seriam os responsáveis pelas alterações no eixo cálcio-PTH-vitamina D. Além disso, o tratamento das DHC com glicocorticóides (fibrose cística) e ribavirina (Hepatite C) parece contribuir como agravante destes distúrbios. Por outro lado, parece ser a osteoporose, e não a osteomalácia ou o hiperparatireoidismo secundário, a principal alteração nas DHC. Assim, continua objeto de discussão o papel das alterações do eixo cálcio-PTH-vitamina D na osteodistrofia hepática.

An open, randomized, controlled study of transdermal hormone replacement therapy on the rate of bone loss in primary biliary cirrhosis

OBJECTIVES

The prevalence of osteoporosis amongst patients with primary biliary cirrhosis (PBC) is high and may be a serious clinical problem. Hormone replacement therapy (HRT) is effective in preventing bone loss but has not been evaluated in randomized trials in PBC. The primary aim was to study the effect of transdermal HRT in combination with daily vitamin D and calcium supplementation on bone loss compared with vitamin D and calcium supplementation only in postmenopausal women with PBC. The secondary aim was to study the safety of transdermal HRT.

SUBJECTS/INTERVENTIONS

Eighteen females with PBC were randomized to receive 2 years therapy with either (i) transdermal oestradiol 50 microg 24 h(-1) two times per week + medroxyprogesterone 2.5 mg day(-1) + alfacalcidol 0.25 microg day(-1) and calcium 1 g day(-1) or (ii) alfacalcidol 0.25 microg day(-1) and calcium 1 g day(-1). Dual-energy X-ray absorptiometry for measurement of bone mineral density (BMD) and sampling of blood and serum for measurements of biochemical markers of liver function was performed before, during and at the end of treatment.

RESULTS

BMD increased significantly at the lumbar spine (P < 0.05) and the femoral neck (P < 0.05) in the HRT group whereas no significant change was found in the control group. One oestrogen-treated patient was excluded after 1 year because of deteriorating, but reversible, aminotransferases. Dropout frequency because of nonliver-related causes was higher in the HRT group. Otherwise, no difference with respect to adverse liver reactions was found between the groups.

CONCLUSION

Transdermal HRT increases BMD in PBC patients with few severe side effects related to the liver.

Rising plasma nociceptin level during development of HCC: a case report

AIM

Although liver cirrhosis is a predisposing factor for hepatocellular carcinoma (HCC), relatively few reports are available on HCC in primary biliary cirrhosis. High plasma nociceptin (N/OFQ) level has been shown in Wilson disease and in patients with acute and chronic pain.

METHODS

We report a follow-up case of HCC, which developed in a patient with primary biliary cirrhosis. The tumor appeared 18 years after the diagnosis of PBC and led to death within two years. Alfa fetoprotein and serum nociceptin levels were monitored before and during the development of HCC. Nociceptin content was also measured in the tumor tissue.

RESULTS

The importance and the curiosity of the presented case was the novel finding of the progressive elevation of plasma nociceptin level up to 17-fold (172 pg/mL) above the baseline (9.2+/-1.8 pg/mL), parallel with the elevation of alpha fetoprotein (from 13 ng/mL up to 3 480 ng/mL) during tumor development. Nociceptin content was more than 15-fold higher in the neoplastic tissue (0.16 pg/mg) than that in the tumor-free liver tissue samples (0.01 pg/mg) taken during the autopsy.

CONCLUSION

Results are in concordance with our previous observation that a very high plasma nociceptin level may be considered as an indicator for hepatocellular carcinoma.

Noninfectious liver disorders: assessment and diagnosis

Infectious hepatitis is often the initial suspect when abnormal serum liver function test results are discovered in primary care settings. However, noninfectious liver disorders may also present with altered liver function tests. Noninfectious liver disorders require careful assessment of patient history, physical findings, and serum laboratory tests to distinguish among entities that have varying clinical implications and treatments.

Primary biliary cirrhosis--presentation and diagnosis

Primary biliary cirrhosis is predominantly seen in middle-aged women. Typical symptoms are fatigue, pruritus, and abdominal pain. Jaundice develops in the endstage disease. At presentation, about 40% of the patients are asymptomatic, but 30% to 50% already have hepatomegaly, and 15% present with splenomegaly. Even patients with fully developed liver cirrhosis may be free of symptoms. Abnormal physical signs and advanced histological stage are more frequent in symptomatic than in asymptomatic patients. Fatigue, pruritus, and Sjögren's syndrome are more common in women than men, but other signs and symptoms do not differ in the two sexes. PBC is associated with a large variety of other diseases, like arthropathy, CREST syndrome, autoimmune thyroiditis, and so on, which in addition will or will not produce symptoms. Hepatocellular carcinoma is a rare complication in women, but more frequent in men. Diagnosis can be established by the triad antimitochondrial antibodies (AMA), cholestatic indices, and liver histology, diagnostic or compatible with PBC. When AMA are not detected, then antinuclear antibodies (autoantibodies against gp.210 and others) can be detected in 50% of AMA-negative patients. AMA titers do not correlate with the course of the disease nor histological progression. After liver transplantation, AMA recur in nearly 100%. The liver enzyme pattern in PBC patients is cholestatic: alkaline phosphatase and gammaglutamyltransferase increase to 10 or more times the upper limit of normal. The amount of enzymes does not correlate with disease progression or stage of the disease. The only prognostic factor in PBC is serum bilirubin. AMA-negative patients account for about 10% to 15%. Routine biochemical tests are not different from AMA-positive patients, but usually higher ANA, SMA, and IgG concentrations are detected. Histologically, it is PBC. The overlap-syndrome, autoimmune hepatitis-PBC presents with the histological features of autoimmune hepatitis and PBC, with AMA, ANA, or SMA. Imaging procedures are not helpful for the diagnosis of PBC, except for liver histology. Histologically, four different stages can be assessed, ranging from florid bile duct lesions, ductular proliferation, and fibrosis to liver cirrhosis. Liver histology is of interest for the assessment of the diagnosis and for staging of the disease.

Osteoporosis: still a typical complication of primary biliary cirrhosis?

BACKGROUND

Osteoporosis is a recognized complication of primary biliary cirrhosis but it has been suggested that its prevalence may overlap that observed among postmenopausal women.

AIM

To evaluate prevalence and risk factors of osteoporosis in primary biliary cirrhosis.

PATIENTS

A total of 133 female patients (age 53+/-10 years, menopausal status 70%, histological stage I-II 61%, portal hypertension 28%, Mayo Risk Score 4.11+/-0.59) were enrolled.

METHODS

Dual X-ray absorptiometry of the lumbar spine.

RESULTS

Mean bone mineral density, T and Z score were 0.861+/-0.160 g/cm2, -1.87+/-1.45 and -0.78+/-2.63, respectively. At multivariate analysis, bone mineral density was inversely correlated with age (p<0.05). Osteoporosis was present in 39/92 (41%) postmenopausal and 8/41 (20%) premenopausal patients. In the premenopausal group, osteoporosis was significantly correlated with serum albumin (p<0.05) and Mayo Risk score (p<0.005). No significant correlation was present in the postmenopausal group.

CONCLUSIONS

Despite the accepted wisdom that osteoporosis is a common complication of primary biliary cirrhosis, its frequency in post-menopausal patients overlaps that observed in the general population, but is much more frequent in premenopausal patients, where it appears to be related to severity of liver disease and cholestasis.

Longitudinal bone loss in postmenopausal women with primary biliary cirrhosis and well-preserved liver function

OBJECTIVES/DESIGN

Increased rate of bone loss has been reported in women with primary biliary cirrhosis (PBC) and varying degree of liver dysfunction. Whether bone loss is increased in patients without liver dysfunction is unclear. The aim of this study was to estimate retrospectively the rate of bone loss in postmenopausal women with PBC and well-preserved liver function.

SUBJECTS/INTERVENTIONS

Forty-three women with PBC, and classified as Child-Pugh class A, were included. Bone mineral density (BMD) was measured by dual energy X-ray absorptiometry at the lumbar spine and the femoral neck.

RESULTS

Median time between measurements of BMD was 26 months (range, 12-48 months). Twenty women were not receiving any bone protective treatment, i.e. hormone replacement therapy (HRT), bisphosphonates or vitamin D/calcium supplementation, whilst 23 women received such treatment. Mean annual bone loss in the former group was 0.38 +/- 2.56% and 0.42 +/- 2.29% at the lumbar spine and the femoral neck, respectively. Women receiving treatment, however, increased their BMD by 1.92 +/- 3.76% and 0.15 +/- 2.75% at the lumbar spine and the femoral neck, respectively. At the lumbar spine the difference with regard to changes in BMD between untreated and treated women was statistically significant (P = 0.02). Women who received HRT (n = 11) increased their BMD at the lumbar spine by 2.95 +/- 3.91%, P = 0.03 when compared with untreated women.

CONCLUSION

Bone loss in postmenopausal women with PBC and well-preserved liver function is not increased above normal. Treatment with bone protective treatment, mainly HRT, improves BMD at the lumbar spine.

Cholestatic syndromes

Further insights into the molecular regulation of bile acid transport and metabolism have provided the basis for a better understanding of the pathogenesis of cholestatic liver diseases. Novel insights into the mechanisms of action of ursodeoxycholic acid should advance our understanding of the treatment of cholestatic liver diseases. Mutations of transporter genes can cause hereditary cholestatic syndromes in both infants and adults as well as cholesterol gallstone disease. Important studies have been published on the pathogenesis, clinical features, and treatment of primary biliary cirrhosis, drug-induced cholestasis, and cholestasis of pregnancy.