Nonalcoholic fatty liver disease(NAFLD) is defined as the presence of hepatic fat accumulation after the exclusion of other causes of hepatic steatosis, including other causes of liver disease, excessive alcohol consu...Nonalcoholic fatty liver disease(NAFLD) is defined as the presence of hepatic fat accumulation after the exclusion of other causes of hepatic steatosis, including other causes of liver disease, excessive alcohol consumption, and other conditions that may lead to hepatic steatosis. NAFLD encompasses a broad clinical spectrum ranging from nonalcoholic fatty liver to nonalcoholic steatohepatitis(NASH), advanced fibrosis, cirrhosis, and finally hepatocellular carcinoma(HCC). NAFLD is the most common liver disease in the world and NASH may soon become the most common indication for liver transplantation. Ongoing persistence of obesity with increasing rate of diabetes will increase the prevalence of NAFLD, and as this population ages, many will develop cirrhosis and end-stage liver disease. There has been a general increase in the prevalence of NAFLD, with Asia leading the rise, yet the United States is following closely behind with a rising prevalence from 15% in 2005 to 25% within 5 years. NAFLD is commonly associated with metabolic comorbidities, including obesity, type Ⅱ diabetes, dyslipidemia, and metabolic syndrome. Our understanding of the pathophysiology of NAFLD is constantly evolving. Based on NAFLD subtypes, it has the potential to progress into advanced fibrosis, end-stage liver disease and HCC. The increasing prevalence of NAFLD with advanced fibrosis, is concerning because patients appear toexperience higher liver-related and non-liver-related mortality than the general population. The increased morbidity and mortality, healthcare costs and declining health related quality of life associated with NAFLD makes it a formidable disease, and one that requires more in-depth analysis.展开更多
Non-alcoholic fatty liver disease(NAFLD) encompasses the simple steatosis to more progressive steatosis with associated hepatitis, fibrosis, cirrhosis, and in some cases hepatocellular carcinoma. NAFLD is a growing ep...Non-alcoholic fatty liver disease(NAFLD) encompasses the simple steatosis to more progressive steatosis with associated hepatitis, fibrosis, cirrhosis, and in some cases hepatocellular carcinoma. NAFLD is a growing epidemic, not only in the United States, but worldwide in part due to obesity and insulin resistance leading to liver accumulation of triglycerides and free fatty acids. Numerous risk factors for the development of NAFLD have been espoused with most having some form of metabolic derangement or insulin resistance at the core of its pathophysiology. NAFLD patients are at increased risk of liver-related as well as cardiovascular mortality, and NAFLD is rapidly becoming the leading indication for liver transplantation. Liver biopsy remains the gold standard for definitive diagnosis, but the development of noninvasive advanced imaging, biochemical and genetic tests will no doubt provide future clinicians with a great deal of information and opportunity for enhanced understanding of the pathogenesis and targeted treatment. As it currently stands several medications/supplements are being used in the treatment of NAFLD; however, none seem to be the "magic bullet" in curtailing this growing problem yet. In this review we summarized the current knowledge of NAFLD epidemiology, risk factors, diagnosis, pathogenesis, pathologic changes, natural history, and treatment in order to aid in further understanding this disease and better managing NAFLD patients.展开更多
This review focuses on research findings in the area of diagnosis and pathogenesis of hepatitis C virus(HCV)infection over the last few decades.The information based on published literature provides an update on these...This review focuses on research findings in the area of diagnosis and pathogenesis of hepatitis C virus(HCV)infection over the last few decades.The information based on published literature provides an update on these two aspects of HCV.HCV infection,previously called blood transmitted non-A,non-B infection,is prevalent globally and poses a serious public health problem worldwide.The diagnosis of HCV infection has evolved from serodetection of non-specific and low avidity anti-HCV antibodies to detection of viral nucleic acid in serum using the polymerase chain reaction(PCR)technique.Current PCR assays detect viral nucleic acid with high accuracy and the exact copy number of viral particles.Moreover,multiplex assays using real-time PCR are available for identification of HCV-genotypes and their isotypes.In contrast to previous methods,the newly developed assays are not only fast and eco-nomic,but also resolve the problem of the window period as well as differentiate present from past infection.HCV is a non-cytopathic virus,thus,its pathogenesis is regulated by host immunity and metabolic changes including oxidative stress,insulin resistance and hepatic steatosis.Both innate and adaptive immunity play an important role in HCV pathogenesis.Cytotoxic lymphocytes demonstrate crucial activity during viral eradication or viral persistence and are influenced by viral proteins,HCV-quasispecies and several metabolic factors regulating liver metabolism.HCV pathogenesis is a very complex phenomenon and requires further study to determine the other factors involved.展开更多
AIM: To investigate the viral and host causes of fatty liver in chronic hepatitis B patients and the role of fat deposits in liver damage.METHODS: A total of 164 patients (113 males and 51 females, average age 35±...AIM: To investigate the viral and host causes of fatty liver in chronic hepatitis B patients and the role of fat deposits in liver damage.METHODS: A total of 164 patients (113 males and 51 females, average age 35±11.3 years, and range 10-62 years) with previously untreated chronic hepatitis B were included in the study. The patients were divided into two groups depending on the result of liver biopsy: group without steatosis (100 patients with ＜5% hepatosteatosis) and group with steatosis (64 patients with ＞5% hepatosteatosis). The groups were compared in terms of gender, body mass index (BMI), liver enzymes (ALT, AST, ALP, GGT), cholesterol, triglyceride, HBeAg, viral load, and histological findings. In the group with steatosis, the patients were subdivided depending on the degree of steatosis into mild group (45 patients with 5-24% steatosis), and severe group (19 patients with ＞25% steatosis). RESULTS: In the group of chronic hepatitis B with steatosis, the mean age, BMI, cholesterol, and triglyceride levels were significantly higher than those in the group without steatosis (P＜0.05). Steatosis was found in 53 (46.9%) of male patients and 11 (22%) of female patients (P＜0.05). No significant difference was found in the positivity of ALT, AST, ALP, GGT, HBeAg, viral load, histological activity index (HAI) and stage between the two groups (P＞0.05). In the group with severe steatosis, the BMI was significantly higher than that in the group with mild steatosis (P＜0.05). No significant difference was found in the other parameters between the groups (P＞0.05). CONCLUSION: Steatosis in chronic hepatitis B appears to be a result of metabolic factors of the host rather than the effect of viruses. Steatosis is unrelated to the HAI and degree of fibrosis, which are considered as the histological indicators of liver damage.展开更多
With the increasing number of individuals with diabetes and obesity,nonalcoholic fatty liver disease(NAFLD) is becoming increasingly prevalent,affecting one-quarter of adults worldwide. The spectrum of NAFLD ranges fr...With the increasing number of individuals with diabetes and obesity,nonalcoholic fatty liver disease(NAFLD) is becoming increasingly prevalent,affecting one-quarter of adults worldwide. The spectrum of NAFLD ranges from simple steatosis or nonalcoholic fatty liver(NAFL) to nonalcoholic steatohepatitis(NASH). NAFLD, especially NASH, may progress to fibrosis, leading to cirrhosis and hepatocellular carcinoma. NAFLD can impose a severe economic burden,and patients with NAFLD-related terminal or deteriorative liver diseases have become one of the main groups receiving liver transplantation. The increasing prevalence of NAFLD and the severe outcomes of NASH make it necessary to use effective methods to identify NAFLD. Although recognized as the gold standard, biopsy is limited by its sampling bias, poor acceptability, and severe complications, such as mortality, bleeding, and pain. Therefore, noninvasive methods are urgently needed to avoid biopsy for diagnosing NAFLD. This review discusses the current noninvasive methods for assessing NAFLD,including steatosis, NASH, and NAFLD-related fibrosis, and explores the advantages and disadvantages of measurement tools. In addition, we analyze potential noninvasive biomarkers for tracking disease processes and monitoring treatment effects, and explore effective algorithms consisting of imaging and nonimaging biomarkers for diagnosing advanced fibrosis and reducing unnecessary biopsies in clinical practice.展开更多
It is estimated that 30% of the adult population in Japan is affected by nonalcoholic fatty liver disease (NAFLD). Fatty changes of the liver are generally diagnosed using imaging methods such as abdominal ultrasonogr...It is estimated that 30% of the adult population in Japan is affected by nonalcoholic fatty liver disease (NAFLD). Fatty changes of the liver are generally diagnosed using imaging methods such as abdominal ultrasonography (US) and computed tomography (CT), but the sensitivity of these imaging techniques is low in cases of mild steatosis. Alanine aminotransferase levels may be normal in some of these patients, warranting the necessity to establish a set of parameters useful for detecting NAFLD, and the more severe form of the disease, nonalcoholic steatohepatitis (NASH). Although liver biopsy is currently the gold standard for diagnosing progressive NASH, it has many drawbacks, such as sampling error, cost, and risk of complications. Furthermore, it is not realistic to perform liver biopsies on all NAFLD patients. Diagnosis of NASH using various biomarkers, scoring systems and imaging methods, such as elastography, has recently been attempted. The NAFIC score, calculated from the levels of ferritin, fasting insulin, and type IV collagen 7S, is useful for the diagnosis of NASH, while the NAFLD fibrosis score and the FIB-4 index are useful for excluding NASH in cases of advanced fibrosis. This article reviews the limitations and merits of liver biopsy and noninvasive diagnostic tests in the diagnosis of NAFLD/NASH.展开更多
The current epidemic of non-alcoholic fatty liver disease(NAFLD) is reshaping the field of hepatology all around the world.The widespread diffusion of metabolic risk factors such as obesity,type2-diabetes mellitus,and...The current epidemic of non-alcoholic fatty liver disease(NAFLD) is reshaping the field of hepatology all around the world.The widespread diffusion of metabolic risk factors such as obesity,type2-diabetes mellitus,and dyslipidemia has led to a worldwide diffusion of NAFLD.In parallel to the increased availability of effective anti-viral agents,NAFLD is rapidly becoming the most common cause of chronic liver disease in Western Countries,and a similar trend is expected in Eastern Countries in the next years.This epidemic and its consequences have prompted experts from all over the word in identifying effective strategies for the diagnosis,management,and treatment of NAFLD.Different scientific societies from Europe,America,and Asia-Pacific regions have proposed guidelines based on the most recent evidence about NAFLD.These guidelines are consistent with the key elements in the management of NAFLD,but still,show significant difference about some critical points.We reviewed the current literature in English language to identify the most recent scientific guidelines about NAFLD with the aim to find and critically analyse the main differences.We distinguished guidelines from 5 different scientific societies whose reputation is worldwide recognised and who are representative of the clinical practice in different geographical regions.Differences were noted in: the definition of NAFLD,the opportunity of NAFLD screening in high-risk patients,the noninvasive test proposed for the diagnosis of NAFLD and the identification of NAFLD patients with advanced fibrosis,in the follow-up protocols and,finally,in the treatment strategy(especially in the proposed pharmacological management).These difference have been discussed in the light of the possible evolution of the scenario ofNAFLD in the next years.展开更多
Nonalcoholic fatty liver disease(NAFLD)is a frequent cause of chronic liver diseases,ranging from simple steatosis to nonalcoholic steatohepatitis(NASH)-related liver cirrhosis.Although liver biopsy is still the gold ...Nonalcoholic fatty liver disease(NAFLD)is a frequent cause of chronic liver diseases,ranging from simple steatosis to nonalcoholic steatohepatitis(NASH)-related liver cirrhosis.Although liver biopsy is still the gold standard for the diagnosis of NAFLD,especially for the diagnosis of NASH,imaging methods have been increasingly accepted as noninvasive alternatives to liver biopsy.Ultrasonography is a well-established and costeffective imaging technique for the diagnosis of hepatic steatosis,especially for screening a large population at risk of NAFLD.Ultrasonography has a reasonable accuracy in detecting moderate-to-severe hepatic steatosis although it is less accurate for detecting mild hepatic steatosis,operator-dependent,and rather qualitative.Computed tomography is not appropriate for general population assessment of hepatic steatosis given its inaccuracy in detecting mild hepatic steatosis and potential radiation hazard.However,computed tomography may be effective in specific clinical situations,such as evaluation of donor candidates for hepatic transplantation.Magnetic resonance spectroscopy and magnetic resonance imaging are now regarded as the most accurate practical methods of measuring liver fat in clinical practice,especially for longitudinal followup of patients with NAFLD.Ultrasound elastography and magnetic resonance elastography are increasingly used to evaluate the degree of liver fibrosis in patients with NAFLD and to differentiate NASH from simple steatosis.This article will review current imaging methods used to evaluate hepatic steatosis,including the diagnostic accuracy,limitations,and practical applicability of each method.It will also briefly describe the potential role of elastography techniques in the evaluation of patients with NAFLD.展开更多
Non-alcoholic fatty liver disease (NAFLD) comprising hepatic steatosis,non-alcoholic steatohepatitis (NASH),and progressive liver fibrosis is considered the most common liver disease in western countries.Fatty liver i...Non-alcoholic fatty liver disease (NAFLD) comprising hepatic steatosis,non-alcoholic steatohepatitis (NASH),and progressive liver fibrosis is considered the most common liver disease in western countries.Fatty liver is more prevalent in overweight than normal-weight people and liver fat positively correlates with hepatic insulin resistance.Hepatic steatosis is regarded as a benign stage of NAFLD but may progress to NASH in a subgroup of patients.Besides liver biopsy no diagnostic tools to identify patients with NASH are available,and no effective treatment has been established.Visceral obesity is a main risk factor for NAFLD and inappropriate storage of triglycerides in adipocytes and higher concentrations of free fatty acids may add to increased hepatic lipid storage,insulin resistance,and progressive liver damage.Most of the adipose tissue-derived proteins are elevated in obesity and may contribute to systemic inflammation and liver damage.Adiponectin is highly abundant in human serum but its levels are reduced in obesity and are even lower in patients with hepatic steatosis or NASH.Adiponectin antagonizes excess lipid storage in the liver and protects from inflammation and fibrosis.This review aims to give a short survey on NAFLD and the hepatoprotective effects of adiponectin.展开更多
There is worldwide epidemic of non-alcoholic fatty liver disease(NAFLD). NAFLD is a clinical entity related to metabolic syndrome. Majority of the patients are obese but the disease can affect non-obese individuals as...There is worldwide epidemic of non-alcoholic fatty liver disease(NAFLD). NAFLD is a clinical entity related to metabolic syndrome. Majority of the patients are obese but the disease can affect non-obese individuals as well. Metabolic factors and genetics play important roles in the pathogenesis of this disorder. The spectrum of disorders included in NAFLD are benign macrovesicular hepatic steatosis, non-alcoholic steatohepatitis, hepatic fibrosis, cirrhosis of liver and hepatocellular carcinoma. Although the disease remains asymptomatic most of the time, it can slowly progress to end stage liver disease. It will be the most common indication of liver transplantation in the future. It is diagnosed by abnormal liver chemistry, imaging studies and liver biopsy. As there are risks of potential complications during liver biopsy, many patients do not opt for liver biopsy. There are some noninvasive scoring systems to find out whether patients have advanced hepatic fibrosis. At the present time, there are limited treatment options which include lifestyle modification to loose weight, vitamin E and thioglitazones. Different therapeutic agents are being investigated for optimal management of this entity. There are some studies done on incretin based therapies in patients with NAFLD. Other potential agents will be silent information regulator protein Sirtuin and antifibrotic monoclonal antibody Simtuzumab against lysyl oxidase like molecule 2. But they are still in the investigational phase.展开更多
Hepatocellular carcinoma(HCC) is the fourth cause of cancer related mortality, and its incidence is rapidly increasing. Viral hepatitis, alcohol abuse, and exposure to hepatotoxins are major risk factors, but nonalcoh...Hepatocellular carcinoma(HCC) is the fourth cause of cancer related mortality, and its incidence is rapidly increasing. Viral hepatitis, alcohol abuse, and exposure to hepatotoxins are major risk factors, but nonalcoholic fatty liver disease(NAFLD) associated with obesity, insulin resistance, and type 2 diabetes, is an increasingly recognized trigger, especially in developed countries. Older age, severity of insulin resistance and diabetes, and iron overload have been reported to predispose to HCC in this context. Remarkably, HCCs have been reported in non-cirrhotic livers in a higher proportion of cases in NAFLD patients than in other etiologies. Inherited factors have also been implicated to explain the different individual susceptibility to develop HCC, and their role seems magnified in fatty liver, where only a minority of affected subjects progresses to cancer. In particular, the common I148 M variant of the PNPLA3 gene influencing hepatic lipid metabolism influences HCC risk independently of its effect on the progression of liver fibrosis. Recently, rare loss-of-function mutations in Apolipoprotein B resulting in very low density lipoproteins hepatic retention and in Telomerase reverse transcriptase influencing cellular senescence have also been linked to HCC in NAFLD. Indeed, hepatic stellate cells senescence has been suggested to bridge tissue aging with alterations of the intestinal microbiota in the pathogenesis of obesity-related HCC. A deeper understanding of the mechanisms mediating hepatic carcinogenesis during insulin resistance, and the identification of its genetic determinants will hopefully provide new diagnostic and therapeutic tools.展开更多
Non-alcoholic fatty liver disease(NAFLD) is a major chronic liver disease that can lead to liver cirrhosis, liver cancer, and ultimately death. NAFLD is pathologically classified as non-alcoholic fatty liver(NAFL) or ...Non-alcoholic fatty liver disease(NAFLD) is a major chronic liver disease that can lead to liver cirrhosis, liver cancer, and ultimately death. NAFLD is pathologically classified as non-alcoholic fatty liver(NAFL) or non-alcoholic steatohepatitis(NASH) based on the existence of ballooned hepatocytes,although the states have been known to transform into each other. Moreover,since the detection of ballooned hepatocytes may be difficult with limited biopsied specimens, its clinical significance needs reconsideration. Repeated liver biopsy to assess histological NAFLD activity for therapeutic response is also impractical, creating the need for body fluid biomarkers and less invasive imaging modalities. Recent longitudinal observational studies have emphasized the importance of advanced fibrosis as a determinant of NAFLD outcome. Thus,identifying predictors of fibrosis progression and developing better screening methods will enable clinicians to isolate high-risk NAFLD patients requiring early intensive intervention. Despite the considerable heterogeneity of NAFLD with regard to underlying disease, patient age, and fibrosis stage, several clinical trials are underway to develop a first-in-class drug. In this review, we summarize the present status and future direction of NAFLD/NASH research towards solving unmet medical needs.展开更多
Estimates of people suffering from overweight (one billion) and obesity (300 million) are increasing. The accumulation of triglycerides in the liver, in the absence of excess alcohol intake, has been described in the ...Estimates of people suffering from overweight (one billion) and obesity (300 million) are increasing. The accumulation of triglycerides in the liver, in the absence of excess alcohol intake, has been described in the early sixties. It was not until 1980, however, that Ludwig et al named this condition nonalcoholic steatohepatitis (NASH). Subsequently, nonalcoholic fatty liver disease (NAFLD) has been used as a general name for conditions ranging from simple steatosis through steatohepatitis to end-stage liver disease (cirrhosis). Many studies have demonstrated the significant correlation with obesity and insulin resistance. Other studies have revealed a signifi- cant correlation between hepatic steatosis, cardiovascu- lar disease and increased intima-media thickness. WHO estimated that at least two million patients will develop cirrhosis due to hepatic steatosis in the years to come. Longitudinal cohort studies have demonstrated that those patients with cirrhosis have a similar risk to devel- op hepatocellular carcinoma as those with other causes of cirrhosis. Taken all together, NAFLD has become the third most important indication for liver transplantation. There- fore, training programmes in internal medicine, gastroen- terology and hepatology should stress the importance of diagnosing this entity and treat properly those at risk for developing complications of portal hypertension and con- comittant cardiovascular disease. This review will focus on the clinical characteristics, pathophysiology, imaging tech- niques and the readily available therapeutic options.展开更多
Nonalcoholic fatty liver disease(NAFLD)is a heterogeneous and complex disease that is imprecisely diagnosed by liver biopsy.NAFLD covers a spectrum that ranges from simple steatosis,nonalcoholic steatohepatitis(NASH)w...Nonalcoholic fatty liver disease(NAFLD)is a heterogeneous and complex disease that is imprecisely diagnosed by liver biopsy.NAFLD covers a spectrum that ranges from simple steatosis,nonalcoholic steatohepatitis(NASH)with varying degrees of fibrosis,to cirrhosis,which is a major risk factor for hepatocellular carcinoma.Lifestyle and eating habit changes during the last century have made NAFLD the most common liver disease linked to obesity,type 2 diabetes mellitus and dyslipidemia,with a global prevalence of 25%.NAFLD arises when the uptake of fatty acids(FA)and triglycerides(TG)from circulation and de novo lipogenesis saturate the rate of FAβ-oxidation and verylow density lipoprotein(VLDL)-TG export.Deranged lipid metabolism is also associated with NAFLD progression from steatosis to NASH,and therefore,alterations in liver and serum lipidomic signatures are good indicators of the disease’s development and progression.This review focuses on the importance of the classification of NAFLD patients into different subtypes,corresponding to the main alteration(s)in the major pathways that regulate FA homeostasis leading,in each case,to the initiation and progression of NASH.This concept also supports the targeted intervention as a key approach to maximize therapeutic efficacy and opens the door to the development of precise NASH treatments.展开更多
AIM: Although an association between hepatic steatosis and vascular risk factors has been described, direct relationships between fatty liver and atherosclerosis have not yet been investigated. The aim of the present ...AIM: Although an association between hepatic steatosis and vascular risk factors has been described, direct relationships between fatty liver and atherosclerosis have not yet been investigated. The aim of the present study has been to investigate those relationships. METHODS: The Study of Health in Pomerania examined a random population sample aged between 20 and 79 years. A study population of 4 222 subjects without hepatitis B and C infections and without liver cirrhosis was available for the present analysis. Hepatic steatosis was defined sonographically and intima-media thickness (IMT) as well as plaque prevalence were estimated by carotid ultrasound. RESULTS: The prevalence rate of hepatic steatosis was 29.9%. Among subjects aged ≥45 years, an association between hepatic steatosis and IMT of the carotid arteries was found in bivariate analysis, but not after adjustment for atherosclerotic risk factors. Individuals with fatty liver had more often carotid plaques than persons without fatty liver (plaque prevalence rate 76.8% vs 66.6%; P<0.001). This association persisted after adjustment for confounding factors and was predominantly present in subjects with no to mild alcohol consumption. CONCLUSION: There is an independent association between hepatic steatosis and carotid atherosclerotic plaques. Metabolic changes due to nonalcoholic fatty liver disease may explain this relationship.展开更多
Alcohol use disorders affect millions of individuals worldwide.Alcohol consumption is directly associated with liver disease mortality and accounts for elevated social and economic costs.Alcoholic liver disease(ALD) m...Alcohol use disorders affect millions of individuals worldwide.Alcohol consumption is directly associated with liver disease mortality and accounts for elevated social and economic costs.Alcoholic liver disease(ALD) may take the form of acute involvement(alcoholic hepatitis)or chronic liver disease(steatosis,steatohepatitis,fibrosis and cirrhosis).The severity and prognosis of alcohol-induced liver disease depends on the amount,pattern and duration of alcohol consumption,as well as on the presence of liver inflammation,diet,nutritional status and genetic predisposition of an individual.While steatosis is an almost completely benign disease,liver cirrhosis is associated with marked morbidity,mortal-ity and life expectancy shortening.The median survival of patients with advanced cirrhosis is 1-2 years.Se-vere acute alcoholic hepatitis(AH)is associated with mortality as high as 50%.It has been managed with corticoids,pentoxifylline and enteral nutrition,although evidence based data are still conflicting.Some author suggest that pentoxifylline could be a better first-line treatment in patients with severe AH.Absolute abstinence is a basic condition for any treatment of acute or chronic ALD,the other therapeutical procedure being of a supportive nature and questionable significance.Acamprosate appears to be an effective treatment strategy for supporting continuous abstinence in alco-hol dependent patients.Patients with advanced liver cirrhosis who demonstrably abstain can be considered for liver transplantation,which leads to a markedly pro-longed life expectancy.The crucial step in ALD preven-tion is in the prevention of alcohol abuse,whereas the prevention of liver injury in active alcohol abusers is not clinically applicable.展开更多
After the first description of fatty pancreas in 1933,the effects of pancreatic steatosis have been poorly investigated,compared with that of the liver. However,the interest of research is increasing. Fat accumulation...After the first description of fatty pancreas in 1933,the effects of pancreatic steatosis have been poorly investigated,compared with that of the liver. However,the interest of research is increasing. Fat accumulation,associated with obesity and the metabolic syndrome(Met S),has been defined as "fatty infiltration" or "nonalcoholic fatty pancreas disease"(NAFPD). The term "fatty replacement" describes a distinct phenomenon characterized by death of acinar cells and replacement by adipose tissue. Risk factors for developing NAFPD include obesity,increasing age,male sex,hypertension,dyslipidemia,alcohol and hyperferritinemia. Increasing evidence support the role of pancreatic fat in the development of type 2 diabetes mellitus,Met S,atherosclerosis,severe acute pancreatitis and even pancreatic cancer. Evidence exists that fatty pancreas could be used as the initial indicator of "ectopic fat deposition",which is a key element of nonalcoholic fatty liver disease and/or Met S. Moreover,in patients with fatty pancreas,pancreaticoduodenectomy is associated with an increased risk of intraoperative blood loss and post-operative pancreatic fistula.展开更多
文摘Nonalcoholic fatty liver disease(NAFLD) is defined as the presence of hepatic fat accumulation after the exclusion of other causes of hepatic steatosis, including other causes of liver disease, excessive alcohol consumption, and other conditions that may lead to hepatic steatosis. NAFLD encompasses a broad clinical spectrum ranging from nonalcoholic fatty liver to nonalcoholic steatohepatitis(NASH), advanced fibrosis, cirrhosis, and finally hepatocellular carcinoma(HCC). NAFLD is the most common liver disease in the world and NASH may soon become the most common indication for liver transplantation. Ongoing persistence of obesity with increasing rate of diabetes will increase the prevalence of NAFLD, and as this population ages, many will develop cirrhosis and end-stage liver disease. There has been a general increase in the prevalence of NAFLD, with Asia leading the rise, yet the United States is following closely behind with a rising prevalence from 15% in 2005 to 25% within 5 years. NAFLD is commonly associated with metabolic comorbidities, including obesity, type Ⅱ diabetes, dyslipidemia, and metabolic syndrome. Our understanding of the pathophysiology of NAFLD is constantly evolving. Based on NAFLD subtypes, it has the potential to progress into advanced fibrosis, end-stage liver disease and HCC. The increasing prevalence of NAFLD with advanced fibrosis, is concerning because patients appear toexperience higher liver-related and non-liver-related mortality than the general population. The increased morbidity and mortality, healthcare costs and declining health related quality of life associated with NAFLD makes it a formidable disease, and one that requires more in-depth analysis.
文摘Non-alcoholic fatty liver disease(NAFLD) encompasses the simple steatosis to more progressive steatosis with associated hepatitis, fibrosis, cirrhosis, and in some cases hepatocellular carcinoma. NAFLD is a growing epidemic, not only in the United States, but worldwide in part due to obesity and insulin resistance leading to liver accumulation of triglycerides and free fatty acids. Numerous risk factors for the development of NAFLD have been espoused with most having some form of metabolic derangement or insulin resistance at the core of its pathophysiology. NAFLD patients are at increased risk of liver-related as well as cardiovascular mortality, and NAFLD is rapidly becoming the leading indication for liver transplantation. Liver biopsy remains the gold standard for definitive diagnosis, but the development of noninvasive advanced imaging, biochemical and genetic tests will no doubt provide future clinicians with a great deal of information and opportunity for enhanced understanding of the pathogenesis and targeted treatment. As it currently stands several medications/supplements are being used in the treatment of NAFLD; however, none seem to be the "magic bullet" in curtailing this growing problem yet. In this review we summarized the current knowledge of NAFLD epidemiology, risk factors, diagnosis, pathogenesis, pathologic changes, natural history, and treatment in order to aid in further understanding this disease and better managing NAFLD patients.
文摘This review focuses on research findings in the area of diagnosis and pathogenesis of hepatitis C virus(HCV)infection over the last few decades.The information based on published literature provides an update on these two aspects of HCV.HCV infection,previously called blood transmitted non-A,non-B infection,is prevalent globally and poses a serious public health problem worldwide.The diagnosis of HCV infection has evolved from serodetection of non-specific and low avidity anti-HCV antibodies to detection of viral nucleic acid in serum using the polymerase chain reaction(PCR)technique.Current PCR assays detect viral nucleic acid with high accuracy and the exact copy number of viral particles.Moreover,multiplex assays using real-time PCR are available for identification of HCV-genotypes and their isotypes.In contrast to previous methods,the newly developed assays are not only fast and eco-nomic,but also resolve the problem of the window period as well as differentiate present from past infection.HCV is a non-cytopathic virus,thus,its pathogenesis is regulated by host immunity and metabolic changes including oxidative stress,insulin resistance and hepatic steatosis.Both innate and adaptive immunity play an important role in HCV pathogenesis.Cytotoxic lymphocytes demonstrate crucial activity during viral eradication or viral persistence and are influenced by viral proteins,HCV-quasispecies and several metabolic factors regulating liver metabolism.HCV pathogenesis is a very complex phenomenon and requires further study to determine the other factors involved.
文摘AIM: To investigate the viral and host causes of fatty liver in chronic hepatitis B patients and the role of fat deposits in liver damage.METHODS: A total of 164 patients (113 males and 51 females, average age 35±11.3 years, and range 10-62 years) with previously untreated chronic hepatitis B were included in the study. The patients were divided into two groups depending on the result of liver biopsy: group without steatosis (100 patients with ＜5% hepatosteatosis) and group with steatosis (64 patients with ＞5% hepatosteatosis). The groups were compared in terms of gender, body mass index (BMI), liver enzymes (ALT, AST, ALP, GGT), cholesterol, triglyceride, HBeAg, viral load, and histological findings. In the group with steatosis, the patients were subdivided depending on the degree of steatosis into mild group (45 patients with 5-24% steatosis), and severe group (19 patients with ＞25% steatosis). RESULTS: In the group of chronic hepatitis B with steatosis, the mean age, BMI, cholesterol, and triglyceride levels were significantly higher than those in the group without steatosis (P＜0.05). Steatosis was found in 53 (46.9%) of male patients and 11 (22%) of female patients (P＜0.05). No significant difference was found in the positivity of ALT, AST, ALP, GGT, HBeAg, viral load, histological activity index (HAI) and stage between the two groups (P＞0.05). In the group with severe steatosis, the BMI was significantly higher than that in the group with mild steatosis (P＜0.05). No significant difference was found in the other parameters between the groups (P＞0.05). CONCLUSION: Steatosis in chronic hepatitis B appears to be a result of metabolic factors of the host rather than the effect of viruses. Steatosis is unrelated to the HAI and degree of fibrosis, which are considered as the histological indicators of liver damage.
基金the Key Project of the National Natural Science Foundation(No.81630011,to H.L.)the National Science Fund for Distinguished Young Scholars(No.81425005,to H.L.)+2 种基金the Major Research Plan of the National Natural Science Foundation of China(No.91639304 and No.91729303,to H.L.)the Creative Group Project of Hubei Province(No.2016CFA010,to H.L.)the Hubei Science and Technology Support Project(No.2018BEC473,to H.L.)
文摘With the increasing number of individuals with diabetes and obesity,nonalcoholic fatty liver disease(NAFLD) is becoming increasingly prevalent,affecting one-quarter of adults worldwide. The spectrum of NAFLD ranges from simple steatosis or nonalcoholic fatty liver(NAFL) to nonalcoholic steatohepatitis(NASH). NAFLD, especially NASH, may progress to fibrosis, leading to cirrhosis and hepatocellular carcinoma. NAFLD can impose a severe economic burden,and patients with NAFLD-related terminal or deteriorative liver diseases have become one of the main groups receiving liver transplantation. The increasing prevalence of NAFLD and the severe outcomes of NASH make it necessary to use effective methods to identify NAFLD. Although recognized as the gold standard, biopsy is limited by its sampling bias, poor acceptability, and severe complications, such as mortality, bleeding, and pain. Therefore, noninvasive methods are urgently needed to avoid biopsy for diagnosing NAFLD. This review discusses the current noninvasive methods for assessing NAFLD,including steatosis, NASH, and NAFLD-related fibrosis, and explores the advantages and disadvantages of measurement tools. In addition, we analyze potential noninvasive biomarkers for tracking disease processes and monitoring treatment effects, and explore effective algorithms consisting of imaging and nonimaging biomarkers for diagnosing advanced fibrosis and reducing unnecessary biopsies in clinical practice.
基金Supported by Scholarship Funds from MSD Co.Ltd.(to Sumida Y)+3 种基金Scholarship Funds from MSD Co.Ltd.Dainippon Sumitomo Pharma Co.Ltd.(to Ioh Y)
文摘It is estimated that 30% of the adult population in Japan is affected by nonalcoholic fatty liver disease (NAFLD). Fatty changes of the liver are generally diagnosed using imaging methods such as abdominal ultrasonography (US) and computed tomography (CT), but the sensitivity of these imaging techniques is low in cases of mild steatosis. Alanine aminotransferase levels may be normal in some of these patients, warranting the necessity to establish a set of parameters useful for detecting NAFLD, and the more severe form of the disease, nonalcoholic steatohepatitis (NASH). Although liver biopsy is currently the gold standard for diagnosing progressive NASH, it has many drawbacks, such as sampling error, cost, and risk of complications. Furthermore, it is not realistic to perform liver biopsies on all NAFLD patients. Diagnosis of NASH using various biomarkers, scoring systems and imaging methods, such as elastography, has recently been attempted. The NAFIC score, calculated from the levels of ferritin, fasting insulin, and type IV collagen 7S, is useful for the diagnosis of NASH, while the NAFLD fibrosis score and the FIB-4 index are useful for excluding NASH in cases of advanced fibrosis. This article reviews the limitations and merits of liver biopsy and noninvasive diagnostic tests in the diagnosis of NAFLD/NASH.
文摘The current epidemic of non-alcoholic fatty liver disease(NAFLD) is reshaping the field of hepatology all around the world.The widespread diffusion of metabolic risk factors such as obesity,type2-diabetes mellitus,and dyslipidemia has led to a worldwide diffusion of NAFLD.In parallel to the increased availability of effective anti-viral agents,NAFLD is rapidly becoming the most common cause of chronic liver disease in Western Countries,and a similar trend is expected in Eastern Countries in the next years.This epidemic and its consequences have prompted experts from all over the word in identifying effective strategies for the diagnosis,management,and treatment of NAFLD.Different scientific societies from Europe,America,and Asia-Pacific regions have proposed guidelines based on the most recent evidence about NAFLD.These guidelines are consistent with the key elements in the management of NAFLD,but still,show significant difference about some critical points.We reviewed the current literature in English language to identify the most recent scientific guidelines about NAFLD with the aim to find and critically analyse the main differences.We distinguished guidelines from 5 different scientific societies whose reputation is worldwide recognised and who are representative of the clinical practice in different geographical regions.Differences were noted in: the definition of NAFLD,the opportunity of NAFLD screening in high-risk patients,the noninvasive test proposed for the diagnosis of NAFLD and the identification of NAFLD patients with advanced fibrosis,in the follow-up protocols and,finally,in the treatment strategy(especially in the proposed pharmacological management).These difference have been discussed in the light of the possible evolution of the scenario ofNAFLD in the next years.
基金Supported by The Basic Science Research Program through the National Research Foundation of South Koreafunded by the Ministry of Education,Science and Technology,No.2012R1A1A1005326
文摘Nonalcoholic fatty liver disease(NAFLD)is a frequent cause of chronic liver diseases,ranging from simple steatosis to nonalcoholic steatohepatitis(NASH)-related liver cirrhosis.Although liver biopsy is still the gold standard for the diagnosis of NAFLD,especially for the diagnosis of NASH,imaging methods have been increasingly accepted as noninvasive alternatives to liver biopsy.Ultrasonography is a well-established and costeffective imaging technique for the diagnosis of hepatic steatosis,especially for screening a large population at risk of NAFLD.Ultrasonography has a reasonable accuracy in detecting moderate-to-severe hepatic steatosis although it is less accurate for detecting mild hepatic steatosis,operator-dependent,and rather qualitative.Computed tomography is not appropriate for general population assessment of hepatic steatosis given its inaccuracy in detecting mild hepatic steatosis and potential radiation hazard.However,computed tomography may be effective in specific clinical situations,such as evaluation of donor candidates for hepatic transplantation.Magnetic resonance spectroscopy and magnetic resonance imaging are now regarded as the most accurate practical methods of measuring liver fat in clinical practice,especially for longitudinal followup of patients with NAFLD.Ultrasound elastography and magnetic resonance elastography are increasingly used to evaluate the degree of liver fibrosis in patients with NAFLD and to differentiate NASH from simple steatosis.This article will review current imaging methods used to evaluate hepatic steatosis,including the diagnostic accuracy,limitations,and practical applicability of each method.It will also briefly describe the potential role of elastography techniques in the evaluation of patients with NAFLD.
基金Supported by The Faculty of Medicine of the University of Regensburg (ReForM C)The Deutsche Forschungsgemein-schaft
文摘Non-alcoholic fatty liver disease (NAFLD) comprising hepatic steatosis,non-alcoholic steatohepatitis (NASH),and progressive liver fibrosis is considered the most common liver disease in western countries.Fatty liver is more prevalent in overweight than normal-weight people and liver fat positively correlates with hepatic insulin resistance.Hepatic steatosis is regarded as a benign stage of NAFLD but may progress to NASH in a subgroup of patients.Besides liver biopsy no diagnostic tools to identify patients with NASH are available,and no effective treatment has been established.Visceral obesity is a main risk factor for NAFLD and inappropriate storage of triglycerides in adipocytes and higher concentrations of free fatty acids may add to increased hepatic lipid storage,insulin resistance,and progressive liver damage.Most of the adipose tissue-derived proteins are elevated in obesity and may contribute to systemic inflammation and liver damage.Adiponectin is highly abundant in human serum but its levels are reduced in obesity and are even lower in patients with hepatic steatosis or NASH.Adiponectin antagonizes excess lipid storage in the liver and protects from inflammation and fibrosis.This review aims to give a short survey on NAFLD and the hepatoprotective effects of adiponectin.
文摘There is worldwide epidemic of non-alcoholic fatty liver disease(NAFLD). NAFLD is a clinical entity related to metabolic syndrome. Majority of the patients are obese but the disease can affect non-obese individuals as well. Metabolic factors and genetics play important roles in the pathogenesis of this disorder. The spectrum of disorders included in NAFLD are benign macrovesicular hepatic steatosis, non-alcoholic steatohepatitis, hepatic fibrosis, cirrhosis of liver and hepatocellular carcinoma. Although the disease remains asymptomatic most of the time, it can slowly progress to end stage liver disease. It will be the most common indication of liver transplantation in the future. It is diagnosed by abnormal liver chemistry, imaging studies and liver biopsy. As there are risks of potential complications during liver biopsy, many patients do not opt for liver biopsy. There are some noninvasive scoring systems to find out whether patients have advanced hepatic fibrosis. At the present time, there are limited treatment options which include lifestyle modification to loose weight, vitamin E and thioglitazones. Different therapeutic agents are being investigated for optimal management of this entity. There are some studies done on incretin based therapies in patients with NAFLD. Other potential agents will be silent information regulator protein Sirtuin and antifibrotic monoclonal antibody Simtuzumab against lysyl oxidase like molecule 2. But they are still in the investigational phase.
文摘Hepatocellular carcinoma(HCC) is the fourth cause of cancer related mortality, and its incidence is rapidly increasing. Viral hepatitis, alcohol abuse, and exposure to hepatotoxins are major risk factors, but nonalcoholic fatty liver disease(NAFLD) associated with obesity, insulin resistance, and type 2 diabetes, is an increasingly recognized trigger, especially in developed countries. Older age, severity of insulin resistance and diabetes, and iron overload have been reported to predispose to HCC in this context. Remarkably, HCCs have been reported in non-cirrhotic livers in a higher proportion of cases in NAFLD patients than in other etiologies. Inherited factors have also been implicated to explain the different individual susceptibility to develop HCC, and their role seems magnified in fatty liver, where only a minority of affected subjects progresses to cancer. In particular, the common I148 M variant of the PNPLA3 gene influencing hepatic lipid metabolism influences HCC risk independently of its effect on the progression of liver fibrosis. Recently, rare loss-of-function mutations in Apolipoprotein B resulting in very low density lipoproteins hepatic retention and in Telomerase reverse transcriptase influencing cellular senescence have also been linked to HCC in NAFLD. Indeed, hepatic stellate cells senescence has been suggested to bridge tissue aging with alterations of the intestinal microbiota in the pathogenesis of obesity-related HCC. A deeper understanding of the mechanisms mediating hepatic carcinogenesis during insulin resistance, and the identification of its genetic determinants will hopefully provide new diagnostic and therapeutic tools.
文摘Non-alcoholic fatty liver disease(NAFLD) is a major chronic liver disease that can lead to liver cirrhosis, liver cancer, and ultimately death. NAFLD is pathologically classified as non-alcoholic fatty liver(NAFL) or non-alcoholic steatohepatitis(NASH) based on the existence of ballooned hepatocytes,although the states have been known to transform into each other. Moreover,since the detection of ballooned hepatocytes may be difficult with limited biopsied specimens, its clinical significance needs reconsideration. Repeated liver biopsy to assess histological NAFLD activity for therapeutic response is also impractical, creating the need for body fluid biomarkers and less invasive imaging modalities. Recent longitudinal observational studies have emphasized the importance of advanced fibrosis as a determinant of NAFLD outcome. Thus,identifying predictors of fibrosis progression and developing better screening methods will enable clinicians to isolate high-risk NAFLD patients requiring early intensive intervention. Despite the considerable heterogeneity of NAFLD with regard to underlying disease, patient age, and fibrosis stage, several clinical trials are underway to develop a first-in-class drug. In this review, we summarize the present status and future direction of NAFLD/NASH research towards solving unmet medical needs.
文摘Estimates of people suffering from overweight (one billion) and obesity (300 million) are increasing. The accumulation of triglycerides in the liver, in the absence of excess alcohol intake, has been described in the early sixties. It was not until 1980, however, that Ludwig et al named this condition nonalcoholic steatohepatitis (NASH). Subsequently, nonalcoholic fatty liver disease (NAFLD) has been used as a general name for conditions ranging from simple steatosis through steatohepatitis to end-stage liver disease (cirrhosis). Many studies have demonstrated the significant correlation with obesity and insulin resistance. Other studies have revealed a signifi- cant correlation between hepatic steatosis, cardiovascu- lar disease and increased intima-media thickness. WHO estimated that at least two million patients will develop cirrhosis due to hepatic steatosis in the years to come. Longitudinal cohort studies have demonstrated that those patients with cirrhosis have a similar risk to devel- op hepatocellular carcinoma as those with other causes of cirrhosis. Taken all together, NAFLD has become the third most important indication for liver transplantation. There- fore, training programmes in internal medicine, gastroen- terology and hepatology should stress the importance of diagnosing this entity and treat properly those at risk for developing complications of portal hypertension and con- comittant cardiovascular disease. This review will focus on the clinical characteristics, pathophysiology, imaging tech- niques and the readily available therapeutic options.
文摘Nonalcoholic fatty liver disease(NAFLD)is a heterogeneous and complex disease that is imprecisely diagnosed by liver biopsy.NAFLD covers a spectrum that ranges from simple steatosis,nonalcoholic steatohepatitis(NASH)with varying degrees of fibrosis,to cirrhosis,which is a major risk factor for hepatocellular carcinoma.Lifestyle and eating habit changes during the last century have made NAFLD the most common liver disease linked to obesity,type 2 diabetes mellitus and dyslipidemia,with a global prevalence of 25%.NAFLD arises when the uptake of fatty acids(FA)and triglycerides(TG)from circulation and de novo lipogenesis saturate the rate of FAβ-oxidation and verylow density lipoprotein(VLDL)-TG export.Deranged lipid metabolism is also associated with NAFLD progression from steatosis to NASH,and therefore,alterations in liver and serum lipidomic signatures are good indicators of the disease’s development and progression.This review focuses on the importance of the classification of NAFLD patients into different subtypes,corresponding to the main alteration(s)in the major pathways that regulate FA homeostasis leading,in each case,to the initiation and progression of NASH.This concept also supports the targeted intervention as a key approach to maximize therapeutic efficacy and opens the door to the development of precise NASH treatments.
基金Supported by Community Medicine Research net (CMR) of the University of Greifswald, which is funded by the Federal Ministry of Education and Research and the Federal State of Mecklenburg-West Pomerania
文摘AIM: Although an association between hepatic steatosis and vascular risk factors has been described, direct relationships between fatty liver and atherosclerosis have not yet been investigated. The aim of the present study has been to investigate those relationships. METHODS: The Study of Health in Pomerania examined a random population sample aged between 20 and 79 years. A study population of 4 222 subjects without hepatitis B and C infections and without liver cirrhosis was available for the present analysis. Hepatic steatosis was defined sonographically and intima-media thickness (IMT) as well as plaque prevalence were estimated by carotid ultrasound. RESULTS: The prevalence rate of hepatic steatosis was 29.9%. Among subjects aged ≥45 years, an association between hepatic steatosis and IMT of the carotid arteries was found in bivariate analysis, but not after adjustment for atherosclerotic risk factors. Individuals with fatty liver had more often carotid plaques than persons without fatty liver (plaque prevalence rate 76.8% vs 66.6%; P<0.001). This association persisted after adjustment for confounding factors and was predominantly present in subjects with no to mild alcohol consumption. CONCLUSION: There is an independent association between hepatic steatosis and carotid atherosclerotic plaques. Metabolic changes due to nonalcoholic fatty liver disease may explain this relationship.
基金Supported by Grant IGA MZCR NT 11 247(The role of protective mechanisms,oxidative stress and inflammatory reaction in the progression of liver damage in patient with metabolic syndrome and possible influence of antioxidative factors on the prevention of liver damage in experimental model of NASH)UK SVV 3362(Regulatory parameters in the pathogenesis of inflammatory and oncologic diseases)
文摘Alcohol use disorders affect millions of individuals worldwide.Alcohol consumption is directly associated with liver disease mortality and accounts for elevated social and economic costs.Alcoholic liver disease(ALD) may take the form of acute involvement(alcoholic hepatitis)or chronic liver disease(steatosis,steatohepatitis,fibrosis and cirrhosis).The severity and prognosis of alcohol-induced liver disease depends on the amount,pattern and duration of alcohol consumption,as well as on the presence of liver inflammation,diet,nutritional status and genetic predisposition of an individual.While steatosis is an almost completely benign disease,liver cirrhosis is associated with marked morbidity,mortal-ity and life expectancy shortening.The median survival of patients with advanced cirrhosis is 1-2 years.Se-vere acute alcoholic hepatitis(AH)is associated with mortality as high as 50%.It has been managed with corticoids,pentoxifylline and enteral nutrition,although evidence based data are still conflicting.Some author suggest that pentoxifylline could be a better first-line treatment in patients with severe AH.Absolute abstinence is a basic condition for any treatment of acute or chronic ALD,the other therapeutical procedure being of a supportive nature and questionable significance.Acamprosate appears to be an effective treatment strategy for supporting continuous abstinence in alco-hol dependent patients.Patients with advanced liver cirrhosis who demonstrably abstain can be considered for liver transplantation,which leads to a markedly pro-longed life expectancy.The crucial step in ALD preven-tion is in the prevention of alcohol abuse,whereas the prevention of liver injury in active alcohol abusers is not clinically applicable.
文摘After the first description of fatty pancreas in 1933,the effects of pancreatic steatosis have been poorly investigated,compared with that of the liver. However,the interest of research is increasing. Fat accumulation,associated with obesity and the metabolic syndrome(Met S),has been defined as "fatty infiltration" or "nonalcoholic fatty pancreas disease"(NAFPD). The term "fatty replacement" describes a distinct phenomenon characterized by death of acinar cells and replacement by adipose tissue. Risk factors for developing NAFPD include obesity,increasing age,male sex,hypertension,dyslipidemia,alcohol and hyperferritinemia. Increasing evidence support the role of pancreatic fat in the development of type 2 diabetes mellitus,Met S,atherosclerosis,severe acute pancreatitis and even pancreatic cancer. Evidence exists that fatty pancreas could be used as the initial indicator of "ectopic fat deposition",which is a key element of nonalcoholic fatty liver disease and/or Met S. Moreover,in patients with fatty pancreas,pancreaticoduodenectomy is associated with an increased risk of intraoperative blood loss and post-operative pancreatic fistula.
