Bone mineral density measurements, bone markers and serum vitamin D concentrations in men with chronic non-cirrhotic untreated hepatitis C

Evaluation and Comparison of Serum Vitamin D Levels between Injection Drug Users with and without Chronic Hepatitis C Infection in Hamadan-Iran

Background and objective: Hepatitis C virus (HCV) infection causes disruption in the metabolism of biochemicals, such as vitamin D, and subsequently alters their serum level via the involvement of the liver. The current study aimed at determining the serum level of vitamin D in injection drug users with chronic HCV infection. Methods:The current case-control study was conducted on 46 injection drug users referred to Imam Khomeini Specialty Clinic in Hamadan City, Iran, between 2017 and 2019, when their HCV infection was diagnosed with HCV PCR test, and 46 healthy injection drug users as the control group in order to compare serum vitamin D levels and liver enzymes. Both the case and control groups were matched for age and gender. ELISA technique was used to measure serum vitamin D level. The collected data were analyzed with STATA software based on 95% significance level. Results:In the present study, 43 (93.5%) of all subjects were male and three (6.6%) females. The mean age of subjects in the case and control groups was 41.87 ± 11.97 and 40.66 ± 11.89 years, respectively. The mean serum vitamin D levels in the case and control groups were 21.20 ± 19.84 and 42.42 ± 29.08 ng/L, respectively (P = 0.001). The mean serum vitamin D levels in the injection drug users with mild, moderate, and severe HCV infection was 32.90, 30.34 and 29.74 ng/L, respectively (P = 0.454). The correlation between vitamin D level and AST and ALT enzymes was -0.053 and -0.103, respectively (P >0.05). Conclusion:Serum vitamin D level decreases in addicts with chronic HCV infection. With increasing the severity of HCV infection, the serum level of vitamin D decreases.

Osteoporosis Remains Constant in Patients with Hemophilia-Long-Term Course in Consideration of Comorbidities

INTRODUCTION

 Patients with hemophilia (PWHs) suffer from an increased risk of osteoporosis. Multiple hemophilia and hemophilic arthropathy associated factors correlate with a low bone mineral density (BMD) in PWHs. The aim of this study was to assess the long-term development of BMD in PWH as well as to analyze potentially influencing factors.

METHODS

 A total of 33 adult PWHs were evaluated in a retrospective study. General medical history, specific-hemophilia-associated comorbidities, joint status using the Gilbert score, calcium level, and vitamin D level as well as at least two results of bone density measurements with a minimum range of 10 years per patient were taken into account.

RESULTS

 The BMD did not change significantly from one point of measurement to the other. A total of 7 (21.2%) cases of osteoporosis and 16 (48.5%) cases of osteopenia were identified. The two following significant correlations could be revealed: the higher the patients' body mass index, the higher their BMD (r = 0.41; p = 0.022). Moreover, a high Gilbert score came along with a low BMD (r = -0.546; p = 0.003).

CONCLUSION

 Even if PWHs frequently suffer from a reduced BMD, our data suggest that their BMD remains constant on a low level in the course of time. A risk factor of osteoporosis often found in PWHs is a vitamin D deficiency and joint destruction. Therefore, a standardized screening of PWHs on BMD reduction by collecting vitamin D blood level and assessing joint status seems appropriate.

Progress in research of non-cirrhotic chronic viral hepatitis with osteoporosis

Osteoporosis is one of the complications of chronic viral hepatitis related cirrhosis, and the pathogenesis and treatment methods for osteoporosis have been extensively studied. However, whether chronic viral hepatitis is the risk factor for osteoporosis is still controversial. Some studies have demonstrated the relationship between them, but there is still no systematic judgment on its pathogenesis and treatment. In this review, we systematically summarize the risk, possible pathogenesis, and treatment scheme of osteoporosis secondary to non-cirrhosis chronic viral hepatitis, with an aim to clarify the relationship between chronic viral hepatitis and osteoporosis, remind clinicians to be alert to the possibility of osteoporosis complicated by chronic viral hepatitis, and provide support for clinical diagnosis and treatment.

Acute bone damage through liver-bone axis induced by thioacetamide in rats

Background

Thioacetamide (TAA) is used in various fields, such as synthetic drugs, organic chemical synthesis, and materials chemistry. TAA is mainly used to establish animal liver injury models and other organ damage models to explore their mechanisms for helping patients with liver disease. Liver damage can lead to abnormal expression of some enzymes in the serum, so we detected the appropriate enzyme levels in the serum of SD rats to verify the damage of TAA to the liver. More importantly, TAA caused bone damage is barely understood. Therefore, our research aims to establish a rat model reflecting the acute bone damage injury caused by TAA.

Methods

The SD rats were intraperitoneally injected with normal saline (0.9%) or TAA (200 mg/kg, 400 mg/kg) for 1 month (once the other day). After the last intraperitoneal injection, serum samples from rats were used for biochemical tests. Masson staining is used to detect liver damage, and micro-CT is used to detect the changes in bone. Moreover, the three-point bending experiment was used to detect the force range of the hind limbs of SD rats.

Results

Compared with the control group, after the intraperitoneal injection of TAA, the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), uric acid (UA), total bile acid (TBA), alkaline phosphatase (ALP), carbamide (UREA) and creatinine (CREA) rose sharply, while the levels of serum content of total protein (TP), lactate dehydrogenase (LDH), calcium (Ca) and phosphorus (P) were severely reduced. After TAA administration, collagen fibers were deposited and liver fibrosis was obvious. Micro-CT results showed that the bone surface, tissue surface, bone volume, and tissue volume of rats with an intraperitoneal injection of TAA were significantly reduced. In addition, the bones of rats with an intraperitoneal injection of TAA can resist less pressure and are prone to fractures.

Conclusions

TAA can cause liver damage in SD rats, which is explained by the changes in serum biochemical indicators and the deposition of liver collagen. More importantly, TAA can reduce bone mineral density and increase the separation of bone trabeculae in SD rats, and finally lead to bone injury. This suggests that TAA may become an ideal model to investigate abnormal bone metabolism after liver injury.

Secondary Osteoporosis and Metabolic Bone Diseases

Fragility fracture is a worldwide problem and a main cause of disability and impaired quality of life. It is primarily caused by osteoporosis, characterized by impaired bone quantity and or quality. Proper diagnosis of osteoporosis is essential for prevention of fragility fractures. Osteoporosis can be primary in postmenopausal women because of estrogen deficiency. Secondary forms of osteoporosis are not uncommon in both men and women. Most systemic illnesses and organ dysfunction can lead to osteoporosis. The kidney plays a crucial role in maintaining physiological bone homeostasis by controlling minerals, electrolytes, acid-base, vitamin D and parathyroid function. Chronic kidney disease with its uremic milieu disturbs this balance, leading to renal osteodystrophy. Diabetes mellitus represents the most common secondary cause of osteoporosis. Thyroid and parathyroid disorders can dysregulate the osteoblast/osteoclast functions. Gastrointestinal disorders, malnutrition and malabsorption can result in mineral and vitamin D deficiencies and bone loss. Patients with chronic liver disease have a higher risk of fracture due to hepatic osteodystrophy. Proinflammatory cytokines in infectious, autoimmune, and hematological disorders can stimulate osteoclastogenesis, leading to osteoporosis. Moreover, drug-induced osteoporosis is not uncommon. In this review, we focus on causes, pathogenesis, and management of secondary osteoporosis.

Hepatitis C virus infection increases the risk of adverse outcomes following joint arthroplasty: A meta-analysis of observational studies

BACKGROUND

Whether hepatitis C virus (HCV)-positive patients are at risk for increased complications and long hospital stay following total joint arthroplasty (TJA) remains unclear. Therefore we performed a meta-analysis aiming to answer the following question: (1) are there differences in postoperative complications including joint infection and mortality between patients with or without hepatitis C following TJAs? (2) Are patients without HCV be associated with less blood loss, shorter hospital stay, lower readmission rate, higher function scores, lower revision and reoperation rates than patients with HCV?

METHODS

A meta-analysis was conducted to pool data and quantitatively assessing the association between HCV infection and risks for adverse postoperative outcomes. A systematic search of all published studies concerning HCV and TJA was performed in five bibliographic databases, including PubMed, EMBASE, China National Knowledge Infrastructure, Web of Science, and the Cochrane Library databases. Random-effects meta-analysis of odds ratios (OR) was accomplished according to the classification of adverse events, subgroup analyses were performed based on surgery type.

RESULTS

Fifteen eligible observational studies were included with a sample size of 9,788,166 patients. Overall pooled data revealed the increased risk of overall complications, including medical and surgical complications, in HCV-positive patients undergoing TJA compared with than in HCV-negative people (OR 1.57; 95%CI: 1.44-1.71 [p<0.00001]). Joint infections were highly common in HCV-positive patients undergoing lower-extremity TJA (OR 2.06; 95%CI: 1.73-2.47 [p<0.00001]). Furthermore, HCV infections were associated with high rates of reoperations and revisions (OR 1.47; 95%CI: 1.40-1.55 [p<0.00001]).

CONCLUSIONS

Patients with hepatitis C have an increased risk of adverse outcomes post-TJA and a high risk of reoperation and revision that is partially attributed to postoperative complications, particularly joint infections.

LEVEL OF EVIDENCE

III; systematic review and meta-analysis.

Patients With Cirrhosis Have Elevated Bone Turnover but Normal Hepatic Production of Osteoprotegerin

CONTEXT

Severe osteodystrophy is common in patients with liver dysfunction. Markers of bone metabolism may help in early diagnosis of osteodystrophy and in understanding underlying pathophysiological mechanisms.

OBJECTIVE

To elucidate changes in bone metabolism associated with cirrhosis and to determine the route of elimination for the markers.

METHODS

Case-control study at a public university hospital. Fifty-nine patients with cirrhosis (47 alcoholic and 12 nonalcoholic cirrhosis) and 20 controls were included. Participants underwent catheterization of the femoral artery, and the hepatic, renal, and femoral veins with collection of blood from all 4 sites. Regional arteriovenous differences in concentrations of bone metabolism markers were determined: procollagen of type I collagen propeptide (PINP), C-terminal cross-linking telopeptide of type I collagen (CTX), osteocalcin, tartrate-resistant acid phosphatase isoform 5b (TRAcP5b), osteoprotegerin (OPG), and sclerostin and correlated with degree of disease (Child-Pugh classification).

RESULTS

PINP concentration was higher (median: 87.9 µg/L) in patients with cirrhosis than in controls (52.6 µg/L) (P = .001), while hepatic extraction was lower (4.3% vs 14.5%) (P < .001). Both CTX and TRAcP5b were higher in patients with cirrhosis (340 ng/L and 3.20 U/L) than in controls (215 ng/L and 1.60 U/L) (P < .001 and P < .0001). Hepatic sclerostin extraction was lower in patients with cirrhosis (14.6%) than in controls (28.7%) (P < .0001). In both groups OPG showed a hepatic release rate (production) of 6%.

CONCLUSION

Patients with cirrhosis have increased bone resorption, but unaltered bone formation. Sclerostin is eliminated through the liver while OPG is produced in the liver. Bone markers may prove useful in evaluating bone turnover in patients with cirrhosis.

An Overview of the Molecular Mechanisms Contributing to Musculoskeletal Disorders in Chronic Liver Disease: Osteoporosis, Sarcopenia, and Osteoporotic Sarcopenia

The prevalence of osteoporosis and sarcopenia is significantly higher in patients with liver disease than in those without liver disease and osteoporosis and sarcopenia negatively influence morbidity and mortality in liver disease, yet these musculoskeletal disorders are frequently overlooked in clinical practice for patients with chronic liver disease. The objective of this review is to provide a comprehensive understanding of the molecular mechanisms of musculoskeletal disorders accompanying the pathogenesis of liver disease. The increased bone resorption through the receptor activator of nuclear factor kappa (RANK)-RANK ligand (RANKL)-osteoprotegerin (OPG) system and upregulation of inflammatory cytokines and decreased bone formation through increased bilirubin and sclerostin and lower insulin-like growth factor-1 are important mechanisms for osteoporosis in patients with liver disease. Sarcopenia is associated with insulin resistance and obesity in non-alcoholic fatty liver disease, whereas hyperammonemia, low amount of branched chain amino acids, and hypogonadism contributes to sarcopenia in liver cirrhosis. The bidirectional crosstalk between muscle and bone through myostatin, irisin, β-aminoisobutyric acid (BAIBA), osteocalcin, as well as the activation of the RANK and the Wnt/β-catenin pathways are associated with osteosarcopenia. The increased understandings for these musculoskeletal disorders would be contributes to the development of effective therapies targeting the pathophysiological mechanism involved.

Outcomes of Patients With Cirrhosis Undergoing Orthopedic Procedures: An Analysis of the Nationwide Inpatient Sample

INTRODUCTION

The population of patients with cirrhosis is growing and shifting toward a more elderly demographic and thus are at risk of developing orthopedic complications. There is lack of data on safety of orthopedic procedures in this population.

METHODS

We performed an analysis of the Nationwide Inpatient Sample from 2005 to 2011 for patients undergoing hip arthroplasty, knee arthroplasty, and spinal laminectomy/fusion, stratified by presence of cirrhosis. The primary endpoint was in-hospital mortality and secondary endpoints included length of stay (LOS) and costs.

RESULTS

There were 693,610 inpatient stays for orthopedic procedures conducted during the study period, with 3014 (0.43%) patients coded as having cirrhosis. Patients with cirrhosis had a lower median age (62 vs. 66 y; P<0.001) and were more likely to be male (52.3% vs. 41.1%; P<0.001). The inpatient mortality rate was significantly higher in patients with cirrhosis (2.4% vs. 0.4%; P<0.001) as was median LOS (4 vs. 3 d; P<0.001) and mean costs ($19,321 vs. $18,833; P<0.001). Patients with decompensated cirrhosis (vs. compensated cirrhosis) had significantly higher inpatient mortality rates (5.8% vs. 1.1%; P<0.001) with higher LOS and costs (P<0.001). On multivariable analysis, cirrhosis was associated with an increased risk of mortality (odds ratio, 4.22; 95% confidence interval, 2.92-6.10). Hospital cirrhosis volume was inversely associated with mortality, while hospital orthopedic procedure volumes had an inconsistent impact on outcomes.

CONCLUSIONS

Inpatient orthopedic procedures in patients with cirrhosis result in high postoperative mortality, LOS, and costs. Careful patient selection is warranted to optimize cirrhosis patient postoperative outcomes.

Hepatic Osteodystrophy-Molecular Mechanisms Proposed to Favor Its Development

Almost all patients with chronic liver diseases (CLD) show altered bone metabolism. Depending on the etiology, this manifests in a severe osteoporosis in up to 75% of the affected patients. Due to high prevalence, the generic term hepatic osteodystrophy (HOD) evolved, describing altered bone metabolism, decreased bone mineral density, and deterioration of bone structure in patients with CLD. Once developed, HOD is difficult to treat and increases the risk of fragility fractures. Existing fractures affect the quality of life and, more importantly, long-term prognosis of these patients, which presents with increased mortality. Thus, special care is required to support the healing process. However, for early diagnosis (reduce fracture risk) and development of adequate treatment strategies (support healing of existing fractures), it is essential to understand the underlying mechanisms that link disturbed liver function with this bone phenotype. In the present review, we summarize proposed molecular mechanisms favoring the development of HOD and compromising the healing of associated fractures, including alterations in vitamin D metabolism and action, disbalances in transforming growth factor beta (TGF-β) and bone morphogenetic protein (BMP) signaling with histone deacetylases (HDACs) as secondary regulators, as well as alterations in the receptor activator of nuclear factor kappa B ligand (RANKL)–osteoprotegerin (OPG) system mediated by sclerostin. Based on these mechanisms, we give an overview on the limitations of early diagnosis of HOD with established serum markers.

Crosssectional Assessment of Bone Mass Density in Adults with Hepatitis B Virus and Hepatitis C Virus Infection

Osteoporosis is one of the major complications in chronic hepatitis B virus (HBV) and hepatitis C (HCV) infection. However, few studies had examined the relationship between hepatic viral infection with bone loss. Our aim was to investigate the association between hepatic viral infection with bone mineral density (BMD) in a cross-sectional study. Participants who attended the health examinations at the Tri-Service General Hospital (TSGH), Taiwan, were enrolled in the study. Diagnosis of viral hepatitis was confirmed by the serum viral markers of hepatitis B surface antigen (HBsAg) and anti-HCV, and BMD measurement was performed by the bone densitometry. Subjects were divided into four groups by the presence of viral markers. The association between hepatic viral infection and BMD was examined by a multivariate linear regression model. HBV infection was inversely associated with BMD after full adjusting with β values of -0.17 (95% CI: -0.29, -0.05) (p < 0.05). The relationship remained significant in males (β = -0.16, 95% CI = -0.31, -0.01) (p < 0.05). In subjects with body mass index less than 30 HBV infection was associated with reduced BMD (β = -0.16, 95% CI = -0.29, -0.02) (p < 0.05). However, HCV infection was only associated with an increase in BMD in patients with BMI less than 30 (β = 0.17, 95% CI = 0.21, 0.32) (p < 0.05). Chronic HBV infection was significantly associated with reduced BMD in males. The impact of viral hepatitis on bone health deserves further investigation for the potential pathophysiological mechanisms.

The association between hepatitis and osteoporosis: a nested case-control study using a national sample cohort

The prevalence of hepatitis B was higher in osteoporosis patients than the control group, especially in females. However, the prevalence of hepatitis C was not different. The matching for various factors improved to have same conditions between osteoporosis patients and the control group.

PURPOSE

Although chronic liver disease, including hepatitis B and hepatitis C, has been associated with osteoporosis in previous studies, the evidence was insufficient, and some findings were inconsistent. The aim of this study was to evaluate the relationship between hepatitis B or hepatitis C and osteoporosis.

METHODS

We used the Korean National Health Insurance Service-National Sample Cohort with ≥ 50-year-old participants from 2002 to 2013. Age was determined at osteoporosis diagnosis. We extracted 68,492 osteoporosis patients (ICD-10 codes E7001-E7004, HC341-HC345) with a 68,492-member control group at a ratio of 1:1 by age, sex, income, region of residence, hypertension, diabetes, and dyslipidemia. We analyzed previous histories of hepatitis B (ICD-10 codes B18.0-B18.1) and hepatitis C (ICD-10 code B18.2) in the osteoporosis patients and control groups. The logistic regression with the crude and adjusted model was analyzed. Additionally, subgroup analyses divided by age and sex were performed.

RESULTS

The adjusted odds ratios for hepatitis B and hepatitis C were 1.19 (95% confidence interval (CI) = 1.11-1.28, P < 0.001) and 1.04 (95% CI = 0.90-1.19, P > 0.05), respectively, in osteoporosis patients. Subgroup analyses showed that the risk of hepatitis B was higher in osteoporosis patients in female groups but not in male groups.

CONCLUSION

Hepatitis B virus infection might be a risk factor for osteoporosis.

Association between pre-sarcopenia, sarcopenia, and bone mineral density in patients with chronic hepatitis C

BACKGROUND

Preserved skeletal muscle is essential for the maintenance of healthy bone. Loss of bone mineral density (BMD) and muscle strength, considered a predictor of BMD, have been demonstrated in patients with cirrhosis, but they are poorly studied in chronic hepatitis C (CHC) without cirrhosis. Thus, we aimed to evaluate the prevalence of low BMD and its association with body composition, muscle strength, and nutritional status in CHC.

METHODS

One hundred and four subjects [mean age, 50.5 ± 11.3 years; 75.0% males; 67.3% non-cirrhotic; and 32.7% with compensated cirrhosis] with CHC, prospectively, underwent scanning of the lean tissue, appendicular skeletal muscle mass (ASM), fat mass, lumbar spine, hip, femoral neck, and whole-body BMD by dual-energy X-ray absorptiometry. Muscle strength was assessed by dynamometry. Sarcopenia was defined by the presence of both low, ASM/height2 (ASMI) and low muscle strength according to the European Working Group on Sarcopenia in Older People criteria. The cut-off points for low ASMI and low muscle strength, for women and men, were < 5.45 and < 7.26 kg/m2 and < 20 and < 30 kg, respectively. According to the adopted World Health Organization criteria in men aged > 50 years, the T-score of osteopenia is between -1.0 and -2.49 standard deviation (SD) below the young average value and of osteoporosis is ≥-2.5 SD below the young normal mean for men, and the Z-score of low bone mass is ≤-2.0 SD below the expected range in men aged < 50 years and women in the menacme. Nutritional status evaluation was based on the Controlling Nutritional Status score.

RESULTS

Low BMD, low muscle strength, pre-sarcopenia, sarcopenia, and sarcopenic obesity were observed in 34.6% (36/104), 27.9% (29/104), 14.4% (15/104), 8.7% (9/104), and 3.8% (4/104) of the patients, respectively. ASMI was an independent predictor of BMD (P < 0.001). Sarcopenia was independently associated with bone mineral content (P = 0.02) and malnutrition (P = 0.01). In 88.9% of the sarcopenic patients and in all with sarcopenic obesity, BMI was normal. The mid-arm muscle circumference was positively correlated with ASMI (r = 0.88; P < 0.001).

CONCLUSIONS

This is the first study to demonstrate that ASM is an independent predictor of BMD in CHC. Mid-arm muscle circumference coupled with handgrip strength testing should be incorporated into routine clinical practice to detect low muscle mass, which may be underdiagnosed when only BMI is used. These findings may influence clinical decision-making and contribute to the development of effective strategies to screen the musculoskeletal abnormalities in CHC patients, independently of the stage of the liver disease.

Bone Health and Impact of Tenofovir Treatment in Men with Hepatitis-B Related Chronic Liver Disease

BACKGROUND

Chronic Liver Disease (CLD) has been shown to have an adverse impact on bone health. Hepatitis-B related CLD and its treatment with tenofovir may have additional effects on skeleton.

OBJECTIVE

To study the impact of HBV related CLD and its treatment with Tenofovir on bone health in Indian subjects.

METHODS

This cross sectional study included men (18-60 years) and comprised of three groups: Group-1 was treatment naïve HBV related CLD (n = 79), Group-2 those with HBV related CLD on tenofovir for at least 1 year (n = 136), Group-3 age, sex and Body Mass Index (BMI) matched healthy controls (n = 58). Bone biochemistry and Bone Mineral Density (BMD) at spine, Femoral Neck (FN) and forearm were studied. Independent t-test or ANOVA was used to compare the means of continuous variables and chi-square test for categorical variables. Multiple logistic regression was used to assess the factors causing Low Bone Mass (LBM) at FN.

RESULTS

A significantly greater proportion (P < 0.05) of patients (40%) with CLD (group 1 and group 2) had vitamin D deficiency (<20 ng/ml) in comparison with control group (22%). The mean serum C-Terminal telopeptide was significantly higher (P < 0.05) and the mean BMD was significantly lower (P < 0.05) in subjects with HBV related CLD than controls. The prevalence of LBM was higher in group 1 at the spine (31%) and forearm (18.4%) when compared to controls (8.1% and 7.8% respectively) (P < 0.05). The proportion of patients with LBM at FN was highest in group 2 (12.3%) compared to those in group 1 (8%) and group 3 (4%) (P < 0.05). Advanced age, low BMI, and high viral load (>10,000 IU/ml) emerged as significant risk factors for LBM at FN.

CONCLUSION

The impact of hepatitis-B related CLD as well as its treatment on bone health is significant. Bone health need to be periodically evaluated in these subjects especially in older men who are lean and have a higher viral load.

Bone mineral density loss in patients with cirrhosis

BACKGROUND/AIMS

Evidence of increased risk of osteoporosis and osteopenia in chronic liver disease and cirrhosis is inconsistent. This study aims to investigate this relationship and to identify the predictors of increased loss of bone mineral density in Saudi patients.

PATIENTS AND METHODS

One hundred and sixty-four patients and controls who are age and gender matched, were included in this study with 1:1 ratio. Patients' included in this study were adults with confirmed liver cirrhosis. Bone mineral densitometry (BMD) at both lumbar spine (LS) and femoral neck (FN) were collected for both groups. Univariate and multivariate regression analyses were performed to identify predictors of BMD loss.

RESULTS

Results showed that cirrhotic patients are at higher risk of developing osteoporosis or osteopenia at LS (OR 2.23, 95% CI [1.19-4.19], P = 0.01) but not at FN, when compared to control sample. Patients with cirrhosis were found to have lower vitamin D and PTH levels (P = 0.0005) and (P = 0.006), respectively. Of the possible predictors tested (gender, age, body mass index [BMI], phosphorus, calcium, parathyroid hormone (PTH), vitamin D, and Model for End Stage Liver Disease [MELD] score), female gender was the main predictor of loss of BMD at LS only (OR 4.80, 95% CI [1.47-15.73], P = 0.01).

CONCLUSIONS

The study showed that cirrhotic patients are at increased susceptibility of having decreased BMD, particularly at the LS and it highlights the need for preventive measures, especially for female patients.

Characteristics and diagnostic workup of the patient at risk to sustain fragility fracture

The human body undergoes several physiological adaptations as a result of the aging process. Amongst other organs, the skeleton is also affected and when bone fragility is present, an increase in both morbidity and mortality has been reported. Identification of risk factors to calculate the probability for a given patient to develop a fragility fracture it is therefore of paramount importance. Moreover, the existence of an in house protocol for diagnostic work up using biochemical tests and imaging investigations is essential. In the herein study we discuss a diagnostic protocol that has been developed in our clinic based on knowledge from the literature and our clinical experience.

Other Extrahepatic Manifestations of Hepatitis C Virus Infection (Pulmonary, Idiopathic Thrombocytopenic Purpura, Nondiabetes Endocrine Disorders)

Extrahepatic manifestations of hepatitis C virus (HCV) infection are a rare but serious condition. This article summarizes the current literature on the association between HCV and endocrine and pulmonary manifestations, as well as idiopathic thrombocytopenic purpura (ITP). HCV may directly infect extrahepatic tissues and interact with the immune system predisposing for obstructive and interstitial lung disease, ITP, autoimmune thyroiditis, infertility, growth hormone and adrenal deficiencies, osteoporosis, and potentially lung and thyroid cancers. However, in many cases, the current evidence is divergent and cannot sufficiently confirm a true association, which emphasizes the need for future targeted projects in this field.

Hepatic Osteodystrophy: The Mechanism of Bone Loss in Hepatocellular Disease and the Effects of Pamidronate Treatment

OBJECTIVES:

The present study was designed to evaluate the bone phenotypes and mechanisms involved in bone disorders associated with hepatic osteodystrophy. Hepatocellular disease was induced by carbon tetrachloride (CCl4). In addition, the effects of disodium pamidronate on bone tissue were evaluated.

METHODS:

The study included 4 groups of 15 mice: a) C = mice subjected to vehicle injections; b) C+P = mice subjected to vehicle and pamidronate injections; c) CCl4+V = mice subjected to CCl4 and vehicle injections; and d) CCl4+P = mice subjected to CCl4 and pamidronate injections. CCl4 or vehicle was administered for 8 weeks, while pamidronate or vehicle was injected at the end of the fourth week. Bone histomorphometry and biomechanical analysis were performed in tibiae, while femora were used for micro-computed tomography and gene expression.

RESULTS:

CCl4 mice exhibited decreased bone volume/trabecular volume and trabecular numbers, as well as increased trabecular separation, as determined by bone histomorphometry and micro-computed tomography, but these changes were not detected in the group treated with pamidronate. CCl4 mice showed increased numbers of osteoclasts and resorption surface. High serum levels of receptor activator of nuclear factor-κB ligand and the increased expression of tartrate-resistant acid phosphatase in the bones of CCl4 mice supported the enhancement of bone resorption in these mice.

CONCLUSION:

Taken together, these results suggest that bone resorption is the main mechanism of bone loss in chronic hepatocellular disease in mice.

Bone health in HIV and hepatitis B or C infections

Chronic infections with human immunodeficiency virus (HIV), hepatitis B virus (HBV) or hepatitis C virus (HCV) add to age-dependent bone loss and may contribute to lower bone strength in the elderly. In this review, we report recent highlights on the epidemiology of bone fragility in chronic viral infections with HIV, HCV and HBV, its physiopathology and discuss the interference of antiviral therapies with bone metabolism. Chronic infections influence bone through the interactions between risk factors for bone fragility and falls (which are highly prevalent in infected patients), virus activity and antiviral drugs. HIV-infected patients are at increased risk of fracture and the risk is higher in cases of co-infection with HIV and untreated chronic viral hepatitis. In HIV patients, the majority of bone loss occurs during virus activity and at initiation of antiretroviral therapy (ART). However, long-term elderly HIV-infected patients on successful ART display bone microstructure alterations only partially captured by dual energy X-ray absorptiometry (DXA). Bone loss is associated with an increase of bone resorption, reflecting the upregulation of the receptor activator of nuclear factor-kappaB ligand (RANKL) and osteoprotegerin (OPG) pathways via a crosstalk between virus activity, inflammation and the immune system. The use of some antiviral drugs, such as tenofovir (controlling both HBV and HIV infections) or protease inhibitors, may be associated with higher bone toxicity. The reduction of tenofovir plasma concentrations with the implementation of tenofovir alafenamide (TAF) attenuates bone mineral density (BMD) loss but it remains unknown whether it will contribute to reducing fracture risk in long-term HIV-treated patients. Moreover, to what extent the new direct-acting agents for treatment of HCV, including nucleotide inhibitors and protease inhibitors, may affect bone health similarly as ART in HIV should be investigated.

Hepatitis C virus infection and risk of osteoporosis: A meta-analysis

BACKGROUND/AIMS

Hepatitis C virus (HCV) infection is one of the most common infections worldwide. Several epidemiologic studies have suggested that patients with HCV infection might be at an increased risk of osteoporosis. However, the data on this relationship remains inconclusive. This meta-analysis was conducted with the aim to summarize all available evidence.

MATERIALS AND METHODS

A literature search was performed using MEDLINE and EMBASE databases from inception to June 2016. Studies that reported relative risks, odd ratios (OR), or hazard ratios comparing the risk of osteoporosis among HCV-infected patients versus those without HCV infection were included. Pooled OR and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method.

RESULTS

Four studies met our eligibility criteria and were included in the analysis. We found a higher risk of osteoporosis among patients with chronic HCV with OR of 1.65 (95% CI: 0.98-2.77). Sensitivity analysis including only studies with higher quality yielded a higher OR, and the result was statistically significant (OR: 2.47; 95% CI: 1.03-5.93).

CONCLUSIONS

Our study demonstrated a higher risk of osteoporosis among HCV-infected patients. Further studies are required to clarify how this risk should be addressed in clinical practice.

Effects of Pegylated Interferon/Ribavirin on Bone Turnover Markers in HIV/Hepatitis C Virus-Coinfected Patients

HIV/hepatitis C virus (HCV) patients have a 3-fold increased fracture incidence compared to uninfected patients. The impact of HCV therapy on bone health is unclear. We evaluated bone turnover markers (BTM) in well-controlled (HIV RNA <50 copies/ml) HIV/HCV-coinfected patients who received pegylated interferon-α and ribavirin (PEG-IFN/RBV) in ACTG trial A5178. Early virologic responders (EVR: ≥2 log HCV RNA drop at week 12) continued PEG-IFN/RBV and non-EVRs were randomized to continuation of PEG-IFN alone or observation. We assessed changes in C-terminal telopeptide of type 1 collagen (CTX; bone resorption marker) and procollagen type I intact N-terminal propeptide (P1NP; bone formation marker), and whether BTM changes were associated with EVR, complete early virologic response (cEVR: HCV RNA <600 IU/ml at week 12), or PEG-IFN treatment. A total of 192 subjects were included. After 12 weeks of PEG-IFN/RBV, CTX and P1NP decreased: −120 pg/ml and −8.48 μg/liter, respectively (both p < 0.0001). CTX declines were greater in cEVR (N = 91; vs. non-cEVR (N = 101; p = 0.003). From week 12 to 24, CTX declines were sustained among EVR patients who continued PEG-IFN/RBV (p = 0.027 vs. non-EVR) and among non-EVR patients who continued PEG-IFN alone (p = 0.022 vs. Observation). Median decreases of P1NP in EVR vs. non-EVR were similar at weeks 12 and 24. PEG-IFN-based therapy for chronic HCV markedly reduces bone turnover. It is unclear whether this is a direct IFN effect or a result of HCV viral clearance, or whether they will result in improved bone mineral density. Further studies with IFN-free regimens should explore these questions.

'Emergency exit' of bone-marrow-resident CD34(+)DNAM-1(bright)CXCR4(+)-committed lymphoid precursors during chronic infection and inflammation

During chronic inflammatory disorders, a persistent natural killer (NK) cell derangement is observed. While increased cell turnover is expected, little is known about whether and how NK-cell homeostatic balance is maintained. Here, flow cytometric analysis of peripheral blood mononuclear cells in chronic inflammatory disorders, both infectious and non-infectious, reveals the presence of a CD34(+)CD226(DNAM-1)(bright)CXCR4(+) cell population displaying transcriptional signatures typical of common lymphocyte precursors and giving rise to NK-cell progenies with high expression of activating receptors and mature function and even to α/β T lymphocytes. CD34(+)CD226(bright)CXCR4(+) cells reside in bone marrow, hardly circulate in healthy donors and are absent in cord blood. Their proportion correlates with the degree of inflammation, reflecting lymphoid cell turnover/reconstitution during chronic inflammation. These findings provide insight on intermediate stages of NK-cell development, a view of emergency recruitment of cell precursors, and upgrade our understanding and monitoring of chronic inflammatory conditions.

Management of endocrine disease: Secondary osteoporosis: pathophysiology and management

Osteoporosis is a skeletal disorder characterized by decreased mass and compromised bone strength predisposing to an increased risk of fractures. Although idiopathic osteoporosis is the most common form of osteoporosis, secondary factors may contribute to the bone loss and increased fracture risk in patients presenting with fragility fractures or osteoporosis. Several medical conditions and medications significantly increase the risk for bone loss and skeletal fragility. This review focuses on some of the common causes of osteoporosis, addressing the underlying mechanisms, diagnostic approach and treatment of low bone mass in the presence of these conditions.

Nonalcoholic fatty liver disease and decreased bone mineral density: is there a link?

PURPOSE

Liver diseases are associated with decreased bone mineral density (BMD) and evidence suggests that nonalcoholic fatty liver disease (NAFLD) affects several extra-hepatic organs, interacting with the regulation of multiple endocrine and metabolic pathways. This review focuses on the rapidly expanding body of evidence that supports a strong association between NAFLD and the risk of decreased BMD, expression of low bone mass (osteoporosis), or reduced mineralization (osteomalacia).

METHODS

We identified studies by searching PubMed for original articles published in English through March 2015 using the keywords "nonalcoholic fatty liver disease" or "fatty liver" combined with "bone mineral density", "osteoporosis", or "osteomalacia".

RESULTS

Recent cross-sectional and case-control studies involving both adults and children have consistently shown that patients with NAFLD exhibit a greater prevalence of decreased BMD compared with age-, sex-, and body mass index-matched healthy controls. Accumulating clinical and experimental evidence suggests that NAFLD may contribute to the pathophysiology of low BMD, possibly through the direct contribution of NAFLD to whole-body and hepatic insulin resistance and/or the systemic release of multiple pro-inflammatory, pro-coagulant, and pro-fibrogenic mediators.

CONCLUSIONS

Although more research is needed before firm conclusions can be drawn, it appears that there is a non-chance, statistical association between NAFLD and low BMD. This finding argues for more careful monitoring and evaluation of BMD among patients with NAFLD. The potential contribution of NAFLD itself to the development and progression of decreased BMD warrants further study.

Osteoporosis and fractures in HIV/hepatitis C virus coinfection: a systematic review and meta-analysis

OBJECTIVE

There is growing evidence that fracture risk is increased in individuals with HIV and/or hepatitis C virus (HCV) infection. We systematically reviewed the literature to determine whether prevalence of osteoporosis and incidence of fracture is increased in HIV/HCV-coinfected individuals.

DESIGN

A systematic review and meta-analysis.

METHODS

A search was performed of Medline, Scopus and the Cochrane Library databases, as well as of abstracts from annual retroviral, liver and bone meetings (up to 2013) for studies with bone mineral density (BMD) or bone fracture data for HIV/ HCV-coinfected individuals. Osteoporosis odds ratios (ORs) and fracture incidence rate ratios (IRRs) were estimated from studies with data on HIV-monoinfected or HIV/HCV uninfected comparison groups.

RESULTS

Of 15 included studies, nine reported BMD data and six reported fracture data. For HIV/HCV-coinfected, the estimated osteoporosis prevalence was 22% [95% confidence interval (95% CI) 12–31] and the crude OR for osteoporosis compared with HIV-monoinfected was 1.63 (95% CI 1.27-2.11). The pooled IRR of overall fracture risk for HIV/HCV-coinfected individuals was 1.77 (95% CI 1.44-2.18) compared with HIV-monoinfected and 2.95 (95% CI 2.17-4.01) compared with uninfected individuals. In addition to HIV/HCV-coinfection, older age, lower BMI, smoking, alcohol and substance use were significant predictors of osteoporosis and fractures across studies.

CONCLUSION

HIV/HCV coinfection is associated with a greater risk of osteoporosis and fracture than HIV monoinfection; fracture risk is even greater than uninfected controls. These data suggest that HIV/HCV-coinfected individuals should be targeted for fracture prevention through risk factor modification at all ages and DXA screening at age 50.