The medical complications of alcohol use: understanding mechanisms to improve management

The use of alcohol in a dependent or even a regular heavy pattern predisposes the drinker to a range of adverse consequences. These include a risk of direct harm from alcohol, including organ damage, mental health disorders and a range of social and legal problems associated with behaviours due to alcohol's effects. The range of organ damage associated with regular heavy alcohol consumption is well described. Much new information on the mechanisms by which damage occurs is available and is reviewed in this paper. New knowledge can assist in the development of more appropriate management strategies for those affected by the medical complications of alcohol use. Genetic susceptibility to tissue injury is explored and the reasons why many heavy drinkers do not appear to experience organ damage are considered. Approaches to the management of certain alcohol-related disorders are outlined.

Hepatitis C -- identifying patients with progressive liver injury

Hepatitis C follows a variable course with some patients developing progressive liver fibrosis, cirrhosis and hepatocellular carcinoma, while others have minimal or no significant liver disease after decades of infection. Studies have identified both host and viral factors associated with disease progression. The importance of general factors such as age at infection, gender, immune status and alcohol consumption has long been recognized; however recently, polymorphisms in a wide array of genes have also been shown to be associated with progressive fibrosis. How specific viral proteins may contribute to disease progression has also been studied. This review highlights what is currently known about the factors associated with progressive liver injury in patients with hepatitis C. A greater understanding of the determinants of disease progression will hopefully lead to improved utilization of existing treatments and ultimately may aid in identification of new therapeutic targets.

Hepatitis C and steatosis: a reappraisal

The overall prevalence of steatosis in patients with Hepatitis C virus (HCV) chronic infection is 55.5% (range 34.8-81.2%). This is a two to threefold increase compared with the prevalence of steatosis in chronic hepatitides because of other aetiologies and of the figures expected on the grounds of a steatosis-HCV chance association. HCV genotype 3 (HCV-3) has specific epidemiological features; furthermore, as compared with HCV-non-3 genotypes, it is associated with a higher prevalence (74.1%vs 47.9%, P < 0.01) and with more severe grades of steatosis (prevalence of grade 3 steatosis 29.6 vs 5.5 P < 0.01). Host and viral factors play a role, although to a variable extent, in the pathogenesis of HCV-3 and non-3 steatosis. HCV load and body mass index are associated with steatosis in HCV-3 and in HCV-non-3 patients respectively. Serum cholesterol levels and liver steatosis at baseline follow an inverse relationship in HCV infection. As hypocholesterolaemia corrects only in those sustained responders to antiviral treatment both in genotype 3 and in non-3 genotypes, the occurrence of a virally induced, acquired and reversible hypobetalipoproteinaemia seems plausible. Steatosis affects the natural course of HCV infection: it is associated with fibrosis, a possible mediator of increased risk to develop type 2 diabetes, it impairs the response to antiviral treatment in HCV-3 patients and might constitute a risk factor for the development of hepatocellular carcinoma. These observations indicate the need to evaluate the efficacy of combined antiviral and 'metabolic' approaches vs standard antiviral regimes in patients with steatosis and HCV chronic infection.

Elevated serum levels of alanine aminotransferase and gamma glutamyltransferase are markers of inflammation and oxidative stress independent of the metabolic syndrome

The present study attempted to establish whether elevated serum levels of alanine aminotransferase (ALT) and gamma glutamyltransferase (GGT) are independent (of each other) markers of systemic inflammation and oxidative stress as assessed by the plasma levels of C-reactive protein (CRP) and lipid peroxides (lipOX), regardless of the presence of underlying metabolic syndrome (as defined by the modified Adult Treatment Panel III (ATPIII) criteria). The plasma levels of CRP and lipOX were determined in 1483 middle-age Japanese men (42+/-9 years). A general linear model analysis indicated that elevated serum ALT and/or serum GGT (levels in the respective highest quartiles) were significantly related to the logarithms of the plasma levels of CRP (Beta=0.08 (0.05-0.11) and 0.08 (0.05-0.11), respectively) and the logarithm of the plasma levels of lipOX (Beta=0.03 (0.01-0.05) and 0.03 (0.01-0.05), respectively), regardless of the presence of underlying metabolic syndrome (MetS) (p<0.01). In addition, the presence of MetS and elevated serum levels of both of these liver enzymes additively increased the plasma levels of CRP and lipOX. Thus, it is proposed that elevated serum ALT and elevated serum GGT are independent markers of the activation of systemic inflammation and increased oxidative stress, independent of their relationship to MetS, and that the presence of MetS and elevations of both of these liver enzymes may additively worsen the atherogenic state.

Drug interactions between psychoactive substances and antiretroviral therapy in individuals infected with human immunodeficiency and hepatitis viruses

The liver disease characteristic of alcohol dependence encompasses three main related entities: steatosis, alcoholic hepatitis, and cirrhosis. Alcoholic cirrhosis is a leading cause of global morbidity and mortality. Alcohol intake among injecting drug users is a major contributor to transmission of viral infections, such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C viruses (HCV). HIV and HCV coinfected patients develop liver diseases earlier and more severely than the monoinfected individuals, including hepatocellular carcinoma. Interactions exist between the therapeutic drugs used to minimize and control the drug and alcohol dependence. Furthermore, drug-drug interactions occur between the highly active antiretroviral therapy (HAART) and alcohol, different HAART components and methadone, or each one of the therapies with the other, thus contributing to a higher toxicity level. With the evolution of effective antiretroviral therapy, survival of persons with HIV, and the syndrome it causes, acquired immunodeficiency syndrome (AIDS) has increased dramatically. Drug-drug interactions may appear between alcohol and anti-HBV or anti-HCV, therapy in the presence or absence of anti-HIV therapy. Several other medical-, social-, and drug-related factors of this population have to be considered when providing HAART. Because many coinfected patients also have problems with substance use, dealing with their drug dependence is an important first step in an attempt to improve adherence to and tolerance of antiviral therapy. It is necessary to minimize the risk of liver disease acceleration and/or reinfection with hepatitis viruses. Knowledge of potential drug interactions between methadone, antiretroviral therapy, psychoactive drugs, and antipsychotics and the role of coinfection with HBV or HCV and the drugs used in eradicating viral hepatitis permits suitable antiretroviral combinations.

Hepatic steatosis and insulin resistance: does etiology make a difference?

BACKGROUND/AIMS

To ascertain whether the etiology of hepatic steatosis modulates insulin resistance (IR) and to determine the predictors of IR.

METHODS

We studied IR through HOMA IR in 146 subjects, 99 of whom had ultrasonographic and/or histologic steatosis. Twenty-two had familial heterozygous hypobetalipoproteinemia (FHBL), 48 had non-alcoholic fatty liver disease (NAFLD), 34 HCV infection (17 with HCV1b, 17 with HCV3a) and 42 were healthy controls without steatosis.

RESULTS

Steatosis was present in 77.3% of FHBL and, by enrolment criteria, in all NAFLD and HCV cases. Overall HOMA-IR correlated with BMI and GGT (P<0.01). FHBL and healthy groups had similar HOMA-IR and GGT values, whereas higher levels were observed in HCV and NAFLD. HCV3a and FHBL patients were hypolipidemic. HOMA-IR was similar in FHBL patients and controls and lower than in HCV and NAFLD. FHBL patients had a high extent of steatosis, similar to that observed in HCV3a, but lower grading and staging than NAFLD and HCV. At multivariate analysis, steatosis and GGT predicted HOMA-IR.

CONCLUSIONS

Data suggest that not all hepatic fat associates with IR. FHBL patients, for some aspects, resemble HCV3a infection, possibly suggesting a shared steatogenic mechanism. Among steatotic patients serum GGT levels is the independent predictor of IR.

Liver disease in patients with diabetes mellitus

Diabetes mellitus is a growing health concern in our society. In addition to the well-known cardiovascular, renal, and ophthalmologic complications of diabetes, liver-related complications occur commonly and are often underrecognized. The ensuing article will review the relationship between diabetes mellitus and two common liver diseases: chronic hepatitis C and nonalcoholic fatty liver disease. The association with diabetes and cirrhosis, acute liver failure, hepatocellular carcinoma, and outcomes following orthotopic liver transplantation will also be discussed.

Hepatitis C virus (HCV) infection and hepatic steatosis

There are two discrete forms of steatosis that may be found in patients infected with hepatitis C virus (HCV). Metabolic steatosis can coexist with HCV, regardless of genotype, in patients with risk factors such as obesity, hyperlipidemia, and insulin resistance. The second form of hepatic steatosis in HCV patients is a result of the direct cytopathic effect of genotype 3 viral infections. There have been proposed mechanisms for this process but it remains elusive. Both categories of steatosis tend to hasten the progression of liver fibrosis and therefore prompt recognition and management should be initiated in patients with HCV and steatosis. The authors review the current understanding of the relationship between hepatitis C infection and hepatic steatosis and discuss future research directions.

Insulin resistance is associated with steatosis in nondiabetic patients with genotype 1 chronic hepatitis C

Conflicting data exist regarding the relationship between hepatitis C virus genotype 1 and hepatic steatosis as well as the latter's role in the progression of fibrosis and treatment response. We assessed factors associated with hepatic steatosis in genotype 1 chronic hepatitis C and the impact of hepatic fat on fibrosis development and interferon responsiveness. Two hundred ninety-one non-diabetic patients with genotype 1 chronic hepatitis C were examined for the presence of steatosis and its correlation with clinical, virological, and biochemical data, including insulin resistance (IR), evaluated by the homeostasis model assessment (HOMA) score. Steatosis was graded as mild (1%-20% of hepatocytes involved), moderate (21%-40% of hepatocytes involved), and severe (>40% of hepatocytes involved). Steatosis was mild in 110 of 291 (37.8%) and moderate/severe in 55 of 291 (18.9%) subjects. By logistic regression, moderate/severe steatosis was independently associated with the female sex (odds ratio [OR] 2.74; 95% CI 1.40-5.35), high gamma-glutamyltransferase levels (OR 1.52; 95% CI 1.22-1.91), and HOMA-score (OR 1.076; 95% CI 1.001-1.26). By logistic regression, moderate/severe steatosis (OR 2.78; 95% CI 1.21-6.4), and platelet counts (OR 0.97; 95% CI 0.96-0.98) were independent predictors of advanced fibrosis. Patients with moderate/severe steatosis had an OR of 0.52 (95% CI 0.30-0.90) for sustained virological response compared with patients with mild/absent steatosis. In conclusion, in nondiabetic European patients with genotype 1 hepatitis C at low risk for the metabolic syndrome, the prevalence of steatosis was nearly 60%. IR is a risk factor for moderate/severe steatosis, especially in men. Moderate/severe steatosis has clinical relevance, being associated with advanced fibrosis and hyporesponsiveness to antiviral therapy.

Hepatic steatosis in chronic hepatitis C: impact on response to anti-viral treatment with peg-interferon and ribavirin

BACKGROUND

There is increasing evidence that hepatic steatosis contributes to the progression of liver fibrosis, whereas its impact on the efficacy of anti-viral treatment is still under investigation.

AIM

To evaluate the effect of steatosis on the outcome of combined anti-viral treatment.

METHODS

We studied 102 consecutive naive patients with chronic hepatitis C receiving combined anti-viral therapy (peg-interferon alpha-2b and ribavirin).

RESULTS

Fifty (49%) of 102 patients had evidence of hepatic steatosis (29 grade 1, 16 grade 2 and 5 grade 3). Sustained virological response was similar in patients with and without steatosis (58% vs. 56%); moreover, the grade of steatosis did not affect the rate of sustained virological response (grade 1: 58%, grade 2: 56% and grade 3: 60%). Patients with steatosis had significantly higher serum levels of aspartate transaminase, alanine transaminase and gamma-glutamyltransferase (P = 0.007, 0.004 and 0.03, respectively), higher histological activity (P = 0.03), more advanced stage of fibrosis (P = 0.0394) and more often hepatitis C virus genotype 3 (P = 0.04).

CONCLUSIONS

Our findings suggest that hepatic steatosis in chronic hepatitis C, irrespective of its grade, is not a negative prognostic factor of response to combined anti-viral therapy, even when the histological and biochemical profile of the disease is more aggressive.

Hepatitis C virus infection can present with metabolic disease by inducing insulin resistance

Although hepatitis C virus (HCV) targets the liver, it has become increasingly evident that HCV can induce diseases of many organs. Recently, much attention is drawn to metabolic disorders in HCV infection. First, hepatic steatosis and derangement in lipid metabolism have been found characteristic of HCV infection, and later on, a correlation was noted between HCV infection and diabetes as well as insulin resistance. We have demonstrated that HCV by itself can induce insulin resistance through disturbing the insulin signaling pathway by HCV proteins. The fact that HCV infection induces insulin resistance by the virus itself may influence the progression of chronic liver disease and open up novel therapeutic approaches. In conclusion, towards the future, HCV infection needs to be viewed not only as a liver disease but also as a metabolic disease.

Nonalcoholic steatohepatitis: pathologic features and differential diagnosis

The worldwide epidemic of obesity has raised the awareness of nonalcoholic fatty liver disease (NAFLD) from that of a curiosity to one of a potentially progressive liver disease with risk for cirrhosis and hepatocellular carcinoma. This overview is focused on the histopathology of the spectrum of fatty liver disease, and discusses the role of liver biopsy, differential diagnoses, and new techniques in development. When pertinent, pathophysiology of this metabolic liver disease and recent treatment considerations have been mentioned as well.

Peroxisome Proliferator-Activated Receptor α L162V Polymorphism in Nonalcoholic Steatohepatitis and Genotype 1 Hepatitis C Virus-Related Liver Steatosis

BACKGROUND

Peroxisome proliferator-activated receptor alpha (PPARalpha) plays important roles in lipid metabolism. A recently discovered L162V polymorphism of the PPARalpha gene is associated with enhanced transcriptional activity. In this study, the frequency of L162V was investigated in nonalcoholic steatohepatitis (NASH) and genotype 1 hepatitis C virus (HCV)-related liver steatosis.

METHODS

Seventy-two NASH and 141 HCV-infected patients (54 with steatosis, 87 without steatosis) and 119 healthy controls were included. L162V polymorphism of the PPARalpha gene was analyzed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP).

RESULTS

PCR and RFLP analysis of the related gene segment was successful in 93%, 96%, and 100% of NASH and HCV-infected patients and controls, respectively. The frequency of the L162V polymorphism was similar in the NASH and HCV-infected patients and controls (5.9%, 3.6%, and 2.5%, respectively). No difference in the frequency of this polymorphism was observed in HCV-infected patients with or without significant liver steatosis. L162V was not associated with obesity, type 2 diabetes mellitus, hypercholesterolemia, or hypertriglyceridemia.

CONCLUSIONS

Neither NASH nor genotype 1 HCV-related liver steatosis seems to be associated with the PPARalpha L162V polymorphism. This polymorphism may have no association with the presence of type 2 diabetes mellitus, obesity, or various blood lipid alterations in NASH and HCV-infected patients.

Review article: hepatitis C virus-associated steatosis--pathogenic mechanisms and clinical implications

Steatosis is a common feature of chronic hepatitis C, and may be caused directly by the virus, as in genotype 3 infection, or be associated with host metabolic factors. The interaction of hepatitis C virus core protein with the lipoprotein secretion pathways causes the characteristic alterations of lipid metabolism observed in hepatitis C virus-related steatosis. Several pathogenic mechanisms are likely involved into the pathogenesis of hepatitis C virus-related steatosis, including hyper-homocysteinaemia, hypoadiponectinaemia and insulin resistance. Steatosis is a major determinant of the liver damage progression in chronic hepatitis C (CHC), and negatively affects the response rate to the interferon (IFN)-based anti-viral treatment. Moreover, recent evidence suggests that steatosis may contribute to liver carcinogenesis. Chronic hepatitis C is a recognized risk factor for type 2 diabetes and it could be implicated into the pathogenesis of atherosclerosis. The role of hepatitis C virus (HCV)-related steatosis in these epidemiological associations remains to be determined.

Review article: hepatic steatosis and insulin resistance

Hepatic steatosis may be both an adaptive phenomenon and an example of lipotoxicity. Its prevalence ranks in the same order of magnitude of insulin resistance in the general population. Studies support the finding that hepatic steatosis is secondary to insulin resistance and not vice versa. A steatotic liver will further contribute to the development of insulin resistance through impaired clearance of insulin from the portal blood, creating a vicious cycle. Insulin resistance is the leading force in the pathogenesis and natural history of non-alcoholic fatty liver disease. Dysfunction of energetic homeostasis and the interaction of adiponectin, leptin and tumour necrosis factor-alpha are key events in the pathogenesis of steatosis and insulin resistance. Insulin resistance represents the frame within which hepatic and extrahepatic non-alcoholic fatty liver disease-related clinical manifestations are to be anticipated and interpreted.

Review article: the metabolic syndrome and non-alcoholic fatty liver disease

Metabolic syndrome represents a common risk factor for premature cardiovascular disease and cancer whose core cluster includes diabetes, hypertension, dyslipidaemia and obesity. The liver is a target organ in metabolic syndrome patients in which it manifests itself with non-alcoholic fatty liver disease spanning steatosis through hepatocellular carcinoma via steatohepatitis and cirrhosis. Given that metabolic syndrome and non-alcoholic fatty liver disease affect the same insulin-resistant patients, not unexpectedly, there are amazing similarities between metabolic syndrome and non-alcoholic fatty liver disease in terms of prevalence, pathogenesis, clinical features and outcome. The available drug weaponry for metabolic syndrome includes aspirin, metformin, peroxisome proliferator-activated receptor agonists, statins, ACE (angiotensin I-converting enzyme) inhibitors and sartans, which are potentially or clinically useful also to the non-alcoholic fatty liver disease patient. Studies are needed to highlight the grey areas in this topic. Issues to be addressed include: diagnostic criteria for metabolic syndrome; nomenclature of non-alcoholic fatty liver disease; enlargement of the clinical spectrum and characterization of the prognosis of insulin resistance-related diseases; evaluation of the most specific clinical predictors of metabolic syndrome/non-alcoholic fatty liver disease and assessment of their variability over the time; characterization of the importance of new risk factors for metabolic syndrome with regard to the development and progression of non-alcoholic fatty liver disease.

Review article: an unexpected virus-host interaction--the hepatitis C virus-diabetes link

There is now consistent epidemiological evidence for an association between chronic hepatitis C and diabetes. Important, although so far limited longitudinal data, have documented an increased risk for diabetes in patients infected by hepatitis C virus (HCV) especially in those with metabolic risk factors such as a high BMI and older age. HCV encoded proteins might alter insulin signalling thus explaining impaired insulin sensitivity and the occurrence of glycaemic dysregulation even before the cirrhotic stage. The consequences of the association between diabetes and HCV infection are an increased liver fibrosis stage and faster fibrosis progression rate. This article reviews recent human and experimental data on the HCV-diabetes association.

Extrahepatic manifestations in patients with chronic hepatitis C virus infection

PURPOSE OF REVIEW

Chronic hepatitis C virus infection often has autoimmune clinical and analytic features. This review analyzes recent data on the close association of chronic hepatitis C virus infection with autoimmune and lymphoproliferative processes.

RECENT FINDINGS

Hepatitis C virus infection has been associated with both organ-specific (thyroiditis, diabetes) and systemic autoimmune diseases. Experimental, virologic, and clinical evidence has demonstrated a close association between hepatitis C virus infection and Sjögren syndrome, with hepatitis C virus-associated Sjögren syndrome being indistinguishable in most cases from the primary form. With respect to rheumatoid arthritis, patients with hepatitis C virus-related polyarthritis and positive rheumatoid factor may fulfill the classification criteria for rheumatoid arthritis. Hepatitis C virus has also been associated with an atypical presentation of antiphospholipid syndrome, as well as with the development of sarcoidosis. A higher prevalence of hematologic processes in patients with hepatitis C virus infection has recently been reported, including cytopenias and lymphoproliferative disorders. Recent data are available on the use of new immunosuppressive and biologic agents (mainly mycophenolate mofetil, anti-tumor necrosis factor agents, and rituximab) in patients with hepatitis C virus infection and autoimmune or lymphoproliferative manifestations.

SUMMARY

There is increasing evidence of a close association of hepatitis C virus infection with autoimmune and hematologic processes. The sialotropism of hepatitis C virus may explain the close association with Sjögren syndrome, and its lymphotropism links the virus to cryoglobulinemia, autoimmune cytopenias, and lymphoma. The substantial overlap between cryoglobulinemic features and the classification criteria for some systemic autoimmune diseases (systemic lupus erythematosus, rheumatoid arthritis, and polyarteritis nodosa) make the differentiation between mimicking and coexistence difficult.

Genotypic variability of hepatitis viruses associated with chronic infection and the development of hepatocellular carcinoma

At least five hepatitis viruses are known to date. Infection by enterically transmitted viruses (HAV and HEV) is generally benign compared with the disease caused by parenterally transmitted viruses (HBV, HCV, and HDV). Chronic infection by HBV is common and may evolve to cirrhosis and hepatocellular carcinoma (HCC). Eight HBV genotypes (A-H) have been described, with the South American genotype F being the most divergent. Seven clades of HDV have been described; among them, the South American genotype III is associated to a high frequency of fulminant hepatitis. HCV infection leads to a high rate of chronicity and HCC. From the six HCV genotypes, infection with genotype 1 might have the worst prognostic. Chronic infection by HCV and HBV is the major risk factor for HCC, which occurs, in the majority of the cases, as a consequence of cirrhosis. However, there is growing evidence that some HBV and HCV proteins might contribute to the generation of HCC. Some HBV and HCV variants and specific mutations within the viral genomes might be more frequently associated with the evolution to HCC. Although more studies are needed, emerging evidence indicates that it might be important to address the genetic variability of these viruses and their contribution to the development of HCC.

Serum adiponectin correlates with viral characteristics but not histologic features in patients with chronic hepatitis C

BACKGROUND/AIMS

Adiponectin induces insulin sensitivity and modulates inflammatory responses. We thus studied the implications of adiponectin in patients with chronic hepatitis C virus (HCV) infection inherently linked to insulin resistance.

METHODS

We analyzed the association of serum adiponectin levels with clinical, virologic, and histologic findings in 95 naive Taiwanese patients with chronic hepatitis C before and after antiviral therapy.

RESULTS

At baseline, 14 (15%) of the 95 patients were obese and 26 (27%) had type 2 diabetes mellitus. Fifty-seven patients were infected with HCV genotype 1 and 38 with genotype 2. Steatosis and periportal fibrosis was present in 44 (46%) and 69 (73%), respectively. In multivariate analysis, male gender, insulin resistance, high HCV load and genotype 2 were significantly associated with a lower serum adiponectin level. In contrast, intrahepatic gene expression of adiponectin receptors was higher in genotype 2 compared with genotype 1. Serum adiponectin level did not correlate with other clinical or histologic parameters. After treatment, change of steatosis also did not correlate with the change of adiponectin level (P=0.61).

CONCLUSIONS

Adiponectin correlated with hepatitis C viral factors at both serum and liver tissue levels. The interactions among adiponectin, insulin resistance and chronic HCV infection merit further studies.

Gallstone disease in non-alcoholic fatty liver: prevalence and associated factors

BACKGROUND

Insulin resistance is a risk factors for non-alcoholic fatty liver disease (NAFLD) and for gallstone disease (GD). Aims of the present study were to assess the prevalence of and factors associated with GD in unselected patients with NAFLD.

METHODS

A total of 161 consecutive patients with NAFLD diagnosed through compatible ultrasonography in the absence of known etiologies of liver disease (in all patients) and/or confirmed histologically (in 61 patients), was studied. Gallstone disease was diagnosed through ultrasound scanning or on the basis of previous cholecystectomy. Anthropometric and biochemical variables and concurrent diseases were compared in 32 NAFLD-GD patients and in 129 NAFLD patients without GD (controls) according to gender.

RESULTS

The overall prevalence of GD was 19.88%, higher in female patients (P < 0.05), who were older (P < 001). The overall percentage of GD increased with age (P < 0.05). The GD patients had higher uric acid (men), total cholesterol and apolipoprotein B (apo-B) serum concentrations (women; P < 0.05); women also had a higher prevalence of hypertriglyceridemia (P < 0.05). The age-corrected odds ratio of having GD by tertiles increased significantly with increasing uric acid (men) and with increasing total cholesterol, triglycerides and apo-B (women). At univariate continuous analysis GD was associated with insulin 120 min and uric acid in male patients; and with body mass index, insulin 120 min, apo-B, total cholesterol and triglycerides in female patients. On multivariate analysis it was found that among these factors only uric acid in men and apo-B in women were independently associated with GD in NAFLD.

CONCLUSIONS

The prevalence of GD in NAFLD is more elevated than reported in the general population. The factors independently associated with GD in NAFLD are different from those reported in the general population and vary according to the gender.

Approach to the management of patients with chronic hepatitis C who failed to achieve sustained virologic response

The combination of peginterferon and ribavirin is the most effective therapy for patients with chronic hepatitis C virus (HCV) infection. Although more than half of all patients are able to achieve a sustained virologic response (SVR), a significant proportion of patients, particularly those with genotype 1, fail to have undetectable HCV RNA during treatment or relapse after completing therapy with return of detectable HCV RNA. The management of these patients creates a formidable challenge. This article outlines various strategies for patients who have failed to achieve SVR and discusses the merits of different approaches to management.

Steatosis: co-factor in other liver diseases

The prevalence of fatty liver is rising in association with the global increase in obesity and type 2 diabetes. In the past, simple steatosis was regarded as benign, but the presence of another liver disease may provide a synergistic combination of steatosis, cellular adaptation, and oxidative damage that aggravates liver injury. In this review, a major focus is on the role of steatosis as a co-factor in chronic hepatitis C (HCV), where the mechanisms promoting fibrosis and the effect of weight reduction in minimizing liver injury have been most widely studied. Steatosis, obesity, and associated metabolic factors may also modulate the response to alcohol- and drug-induced liver disease and may be risk factors for the development of hepatocellular cancer. The pathogenesis of injury in obesity-related fatty liver disease involves a number of pathways, which are currently under investigation. Enhanced oxidative stress, increased susceptibility to apoptosis, and a dysregulated response to cellular injury have been implicated, and other components of the metabolic syndrome such as hyperinsulinemia and hyperglycemia are likely to have a role. Fibrosis also may be increased as a by-product of altered hepatocyte regeneration and activation of bipotential hepatic progenitor cells. In conclusion, active management of obesity and a reduction in steatosis may improve liver injury and decrease the progression of fibrosis.

The extent of liver steatosis in chronic hepatitis C virus infection is mirrored by caspase activity in serum

Hepatic steatosis is a frequent histological alteration in chronic hepatitis C virus (HCV) infection that sensitizes the liver to cell injury, inflammation, and fibrosis via unclear mechanisms. Although apoptosis has been implicated in various liver diseases, its importance in HCV-associated steatosis is largely unknown. In this study, we investigated the role of caspases, the key regulators of apoptosis, and employed two novel caspase assays, an immunological and a luminometric enzyme test, to detect hepatic caspase activation in sera from HCV patients with different grades of steatosis. Our data show that increased caspase activation can be found not only in liver biopsies, but also in sera from HCV patients with liver steatosis. Patients with steatosis exhibited significantly higher serum levels of caspase activity compared with normal healthy individuals. Moreover, the extent of steatosis closely correlated with serum caspase activity, whereas in particular in cases of low or moderate steatosis, no correlation was found with aminotransferase levels. In conclusion, apoptotic caspase activation is considerably elevated in HCV-associated steatosis. More importantly, our data imply that measurement of caspase activation might be a sensitive serum biomarker to detect liver steatosis in patients with chronic HCV infection and other liver diseases.

Genes transactivated by hepatitis C virus core protein, a microarray assay

AIM: To explore the new target genes transactivated by hepatitis C virus (HCV) core protein and to elucidate the pathogenesis of HCV infection.

METHODS: Reverse transcribed cDNA was subjected to microarray assay. The coding gene transactivated by HCV core protein was cloned and analyzed with bioinformatics methods.

RESULTS: The expressive vector of pcDNA3.1(-)-core was constructed and confirmed by restriction enzyme digestion and DNA sequencing and approved correct. mRNA was purified from HepG2 and HepG2 cells transfected with pcDNA3.1(-)-core, respectively. The cDNA derived was subjected to microarray assay. A new gene named HCTP4 was cloned with molecular biological method in combination with bioinformatics method.

CONCLUSION: HCV core is a potential transactivator. Microarray is an efficient and convenient method for analysis of differentially expressed genes.

Hyperhomocysteinemia and the MTHFR C677T polymorphism promote steatosis and fibrosis in chronic hepatitis C patients

The factors and mechanisms implicated in the development of hepatitis C virus (HCV)-related steatosis are unknown. Hyperhomocysteinemia causes steatosis, and the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism induces hyperhomocysteinemia. We investigated the role of these factors in the development of HCV-related steatosis and in the progression of chronic hepatitis C (CHC). One hundred sixteen CHC patients were evaluated for HAI, fibrosis and steatosis grades, body mass index, HCV genotypes, HCV RNA levels, homocysteinemia, and the MTHFR C677T polymorphism. Hyperhomocysteinemia was associated with the TT genotype of MTHFR (r = 0.367; P = .001). Median values of homocysteine in the CC, CT, and TT genotypes of the MTHFR gene were 9.3, 12.2, and 18.6 micromol/L, respectively (P = .006). Steatosis correlated with the MTHFR polymorphism, homocysteinemia, HAI and fibrosis. Steatosis above 20% was significantly associated with fibrosis. Prevalence and high grade (>20%) of steatosis were 41% and 11% in CC, 61% and 49% in CT, and 79% and 64% in TT, respectively (P = .01). Relative risk of developing high levels of steatosis was 20 times higher for TT genotypes than CC genotypes. According to multivariate analysis, steatosis was independently associated with hyperhomocysteinemia (OR = 7.1), HAI (OR = 3.8), liver fibrosis (OR = 4.0), and HCV genotype 3 (OR = 4.6). On univariate analysis, fibrosis was associated with age, steatosis, MTHFR, homocysteinemia and HAI; however, on multivariate analysis, liver fibrosis was independently associated with age (P = .03), HAI (P = .0001), and steatosis (P = .007). In conclusion, a genetic background such as the MTHFR C677T polymorphism responsible for hyperhomocysteinemia plays a role in the development of higher degree of steatosis, which in turn accelerates the progression of liver fibrosis in CHC.

Fibrosis correlates with a ductular reaction in hepatitis C: roles of impaired replication, progenitor cells and steatosis

The mechanisms for progressive fibrosis and exacerbation by steatosis in patients with chronic hepatitis C (HCV) are still unknown. We hypothesized that proliferative blockade in HCV-infected and steatotic hepatocytes results in the default activation of hepatic progenitor cells (HPC), capable of differentiating into both biliary and hepatocyte lineages, and that the resultant ductular reaction promotes portal fibrosis. To study this concept, 115 liver biopsy specimens from subjects with HCV were scored for steatosis, inflammation, and fibrosis. Biliary epithelium and HPC were decorated by cytokeratin 7 immunoperoxidase, and the replicative state of hepatocytes was assessed by p21 and Ki-67 immunohistochemistry. A ductular reaction at the portal interface was common. There was a highly significant correlation between the area of ductular reaction and fibrosis stage (r = 0.453, P < .0001), which remained independently associated after multivariate analysis. HPC numbers also correlated with fibrosis (r = 0.544, P < .0001) and the ductular area (r = 0.624, P < .0001). Moreover, steatosis correlated with greater HPC proliferation (r = 0.372, P = .0004) and ductular reaction (r = 0.374, P < .0001) but was not an obligate feature. Impaired hepatocyte replication by p21 expression was independently associated with HPC expansion (P = .002) and increased with the body mass index (P < .001) and lobular inflammation (P = .005). In conclusion, the strong correlation between portal fibrosis and a periportal ductular reaction with HPC expansion, the exacerbation by steatosis, and the associations with impaired hepatocyte replication suggest that an altered regeneration pathway drives the ductular reaction. We believe this triggers fibrosis at the portal tract interface. This may be a stereotyped response of importance in other chronic liver diseases.

Proposal for a histological scoring and grading system for non-alcoholic fatty liver disease

AIM/BACKGROUND

The spectrum of histopathological features in non-alcoholic fatty liver disease (NAFLD) has been well described. At least two scoring systems have been established. We propose here a system in which numerical scores are obtained using the different features.

METHODS

Twenty-five cases of well-defined NAFLD were identified. Two pathologists blinded to identifiers and clinical data independently scored the liver biopsies twice for portal fibrosis (PF: 0-6), lobular inflammation and necrosis (LIN: 0-3), Mallory bodies (MB: 0-3), hepatocyte ballooning (HB: 0-3), perisinusoidal fibrosis (PSF: 0-3) and fatty change (FC: 1-4). The kappa statistic tested observer concordance. Non-parametric measures of correlation and hierarchical cluster analysis were used to elaborate a grading system.

RESULTS

A broad spectrum of NAFLD was observed. Intra- and interobserver concordance was satisfactory. An activity score was created (AS: 0-12) as the sum of LIN, MB, HB and PSF, but not FC. A system for severity of NAFLD was developed: Grade 1 (PF: 0-2 and AS: 0-4), Grade 2 (PF: 3 or AS: 5-7) and Grade 3 (PF: 4-6 or AS: 8-12). Diabetes, elevated alkaline phosphatase and decreased platelets were associated with advanced grade.

CONCLUSIONS

This simple, reproducible NAFLD score produces a three-tier severity grade. This numerical system may prove useful in assessing disease severity and interval changes.

Decreased plasma adiponectin concentrations are closely related to steatosis in hepatitis C virus-infected patients

OBJECTIVES

The mechanisms underlying steatosis during hepatitis C virus (HCV) infection are complex and multifactorial. Obesity is a well-recognized risk factor for the development of steatosis in chronic hepatitis C infection. The aim of our study was to investigate the role of adipocytokines in HCV-related steatosis. Therefore, we hypothesized that the endocrine function of adipose tissue could be, in part, responsible for HCV-related steatosis. Seventy-one consecutive untreated chronic hepatitis C patients were studied to assess the effects of adipocytokines, body mass index (BMI), age, and HCV genotype on steatosis. We used ELISA to determine serum adiponectin, leptin, and soluble TNF receptors I and II concentrations.

RESULTS

Steatosis was observed in 42 (59.1%) patients. BMI was significantly associated with leptin (r = 0.64; P = 0.0001) and was border significantly associated with adiponectin concentrations (r = -0.22; P = 0.06). In univariate analyses, age, HCV genotype 3, BMI, increased leptin level, increased insulin level, and decreased adiponectin concentration were associated with steatosis. In multivariate analysis, steatosis was significantly associated with low adiponectin concentration, age, HCV genotype 3, and aspartate aminotransferase (ASAT) level, whereas steatosis was not associated with leptin, insulin, and BMI.

CONCLUSION

In chronic HCV patients, hypoadiponectinemia is significantly associated with the development of liver steatosis. The fact that the plasma levels of adiponectin inversely correlate with steatosis in HCV-infected subjects suggests that hypoadiponectinemia may contribute to hepatic steatosis progression and liver injury in this population. One practical implication is that therapy to increase circulating adiponectin concentration, such as overweight reduction or thiazolidinediones, provides the potential to improve steatosis in chronic hepatitis C infection.

Hepatic steatosis and antiretroviral drug use among adults coinfected with HIV and hepatitis C virus

OBJECTIVE

To ascertain the prevalence and severity of hepatic steatosis among patients coinfected with HIV and hepatitis C virus (HCV) who had been taking antiretroviral therapy (ART); to investigate if steatosis is associated with more advanced liver disease, and to identify factors that might contribute to the process.

METHODS

Steatosis was assessed among a randomly selected subset of HIV-HCV-coinfected patients who had received at least 2 years of ART in a cohort study at the Johns Hopkins University HIV clinic. Liver histology was evaluated by a single pathologist. The primary outcome measure was the hepatic steatosis grade, which was classified on a 5 point scale: 0, none; 1, steatosis involving < 5% of hepatocytes; 2, 5-29%; 3, 30-60%; 4 > 60%.

RESULTS

Liver histology was assessed in 112 patients, 74% of whom were taking ART at the time of biopsy. The median cumulative exposure to nucleoside reverse transcriptase inhibitors and protease inhibitors was 5.8 and 3.7 years, respectively. No steatosis was detected in 60%; grades 2-4 steatosis was recognized in 18%. In multivariate analysis, steatosis was independently associated with Caucasian race, weight > 86 kg, hyperglycemia, and stavudine use. Patients with steatosis also were more likely to have greater hepatic fibrosis (P = 0.02) and necroinflammatory activity (P = 0.005).

CONCLUSIONS

Steatosis was observed in 40% of HIV-HCV-coinfected patients with extensive ART exposure and was associated with more severe HCV-related liver disease. Metabolic abnormalities (excess weight and hyperglycemia) and stavudine use were modifiable risk factors for steatosis in this population.

Hepatitis C virus-induced hepatocellular steatosis

Two distinct forms of hepatocellular steatosis can be seen in patients with chronic hepatitis C virus (HCV) infection. Classical metabolic risk factors for hepatocellular steatosis account for the vast majority of cases of steatosis in patients infected by non-genotype 3 HCV strains. In contrast, in patients infected by HCV genotype 3, steatosis is generally induced by the virus itself through a direct cytopathic effect, the mechanisms of which remain debated. Mixed forms of steatosis can also be seen in HCV genotype 3-infected patients with metabolic risk factors. Hepatocellular steatosis appears to be associated with more rapid progression of hepatic fibrosis. However, it is unclear whether this association is due to steatosis itself, or rather to metabolic and host factors that promote steatosis and fibrosis concomitantly. This review discusses current knowledge of HCV-induced steatosis and its relation to chronic HCV-associated liver disease.

Insulin resistance impairs sustained response rate to peginterferon plus ribavirin in chronic hepatitis C patients

BACKGROUND & AIMS

We evaluated the effect of insulin resistance and viral factors on sustained virological response in patients with chronic hepatitis C treated with peginterferon plus ribavirin.

METHODS

Patients (n=159; 94 men; age, 41.7 +/- 11.1 years) with chronic hepatitis C (genotype 1, n=113; non-1 genotype, n=46) received treatment with interferon plus ribavirin. Serum levels of leptin and insulin were measured, and the insulin resistance index (HOMA-IR: homeostasis model of assessment) and body mass index were calculated.

RESULTS

A sustained virological response was associated with lower age, insulin resistance index, body mass index, and gamma-glutamyltranspeptidase and serum leptin levels. There was no association with viral load, sex, type of interferon, or cholesterol levels. A sustained virological response was achieved in 43.4% (46/113) of genotype 1 and 89% (32/36) of genotype 2 and 3 (P=.0001) patients. Necroinflammatory activity and steatosis were not associated with the sustained virological response rate. Multivariate regression analysis indicated that the independent variables related to sustained virological response were genotype (odds ratio, 3.57; 95% confidence interval, 1.49-8.3; P=.001), insulin resistance index (odds ratio, 1.82; 95% confidence interval, 1.08-3.06; P=.012), and fibrosis (odds ratio, 1.36; 95% confidence interval, 1.01-1.84; P=.029). A sustained virological response in patients with genotype 1 and insulin resistance (HOMA-IR > 2) occurred in 23 of 70 (32.8%; 95% confidence interval, 21.9%-43.9%) patients, vs. 26 of 43 (60.5%; 95% confidence interval, 45.9%-75.1%) genotype 1 patients without insulin resistance (P=.007; odds ratio, 3.12, 95% confidence interval, 1.42-6.89).

CONCLUSIONS

Insulin resistance, fibrosis, and genotype are independent predictors of the response to antiviral therapy in chronic hepatitis C patients treated with peginterferon plus ribavirin.

Identification of chronic hepatitis B patients without significant liver fibrosis by a simple noninvasive predictive model

OBJECTIVE

Histological assessment of liver fibrosis is important in the management of chronic hepatitis B (CHB) infection but poorly accepted by patients because of its invasiveness. The aim of this study was to develop a noninvasive model to assess liver fibrosis in CHB patients using clinical and routine laboratory data.

PATIENTS AND METHODS

This was a retrospective study on 235 treatment-naive viremic CHB patients. Univariate analysis of data from the training cohort (n = 150) followed by multivariate logistic regression were performed to identify independent predictors of significant fibrosis and generate predictive models. The models were validated with the remaining patients or validation cohort (n = 85) and by receiver operating characteristics (ROC) analysis.

RESULTS

Body mass index (BMI), platelet count, serum albumin, and total bilirubin levels were identified as independent predictors of bridging fibrosis or cirrhosis (Ishak stage 3-6). ROC analysis was performed using the predictive probabilities derived from the regression models. The area under the ROC curve of the best model was 0.803 (95% CI: 0.729-0.878) for the training cohort, 0.765 (95% CI: 0.644-0.885) for the validation cohort, and 0.791 (95% CI: 0.728-0.854) for the entire cohort. Using the low cut-off probability of 0.15, significant fibrosis could be excluded in 83 patients of the total patient population (negative predictive value 0.92).

CONCLUSIONS

Our noninvasive model comprising BMI and three routine laboratory tests was accurate in predicting absence of significant fibrosis. Application of this model could provide useful additional information on the stage of disease, guide future management decisions, and potentially decrease the need for liver biopsy in some CHB patients.

The Role of Hepatitis C Virus (HCV) in Mitochondrial Dna Damage in HIV/HCV-Coinfected Individuals

Oxidative stress accompanying hepatitis C virus (HCV) infection seems to result in mitochondrial (mt) dysfunction. In HIV/HCV-coinfected individuals, HCV-related mt damage could be further enhanced and clinical manifestations of mt damage may appear, particularly following exposure to some antiretroviral drugs. Furthermore, when HCV medications are used together with certain antiretrovirals, the risk of developing mt adverse events may be particularly frequent, such as development of pancreatitis when ribavirin and didanosine are coadministered. The management of HIV/HCV-coinfected individuals needs to consider the high risk of mitochondria-associated toxicities in this population, which may significantly influence treatment decisions and therapeutic modalities.

Should nonalcoholic fatty liver disease be renamed?

BACKGROUND

None of the synonyms of nonalcoholic fatty liver disease (NAFLD) include clinical correlates nor do they mention insulin resistance, a recognized determinant of the etiopathogenesis and natural history of NAFLD.

METHOD

The literature concerning the pathogenesis and definition of NAFLD is reviewed.

RESULTS

The reasons why NAFLD should be renamed are: (a) clinically meaningful hepatic steatosis could be present at less than 5% triglyceride hepatic content; (b) steatosis is usually no longer observed in the most advanced forms of NAFLD ('cryptogenic cirrhosis'); (c) the concurrence of metabolic derangements could be more important than alcohol in the pathogenesis of alcoholic liver disease; (d) a concurrent metabolic etiology might worsen the course of chronic HCV and autoimmune hepatitis; (e) in NAFLD the liver is a target organ of the metabolic syndrome, a systemic subclinical inflammatory state.

CONCLUSION

The introduction of a positive criterion also mentioned in its definition would benefit the diagnosis of NAFLD and of steatohepatitis observed in the setting of other liver diseases, help to estimate the risk of its progression and aid the treatment of metabolic (fatty) liver disorders. There is a compelling need for an experts' agreement on a new definition of insulin resistance/metabolic-related liver disease.

Plasma adiponectin is decreased in nonalcoholic fatty liver disease

OBJECTIVES

Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver-related morbidity and is frequently associated with obesity and metabolic syndrome. The recently discovered hormone adiponectin is produced by adipose tissue, and low plasma adiponectin is considered a key factor in the development of the insulin resistance underlying metabolic syndrome. Animal studies suggest that adiponectin may protect against non-alcoholic steatohepatitis, but direct evidence in humans is lacking. We therefore conducted this study to assess the relationship between plasma adiponectin and nonalcoholic fatty liver disease to explore its role in the pathogenesis of this disease.

DESIGN AND METHODS

We measured plasma adiponectin and anthropometric, biochemical, hormonal and metabolic correlates in a group of 17 NAFLD patients with diagnosis confirmed by biopsy, and 20 controls with comparable age, body-mass index and sex. Furthermore we compared plasma adiponectin in patients with simple steatosis and steatohepatitis.

RESULTS

Plasma adiponectin was significantly lower in NAFLD patients than controls (5.93+/-0.45 vs 15.67+/-1.60ng/ml). Moreover, NAFLD patients were significantly more insulin resistant while having similar serum leptin. Adiponectin was similar in simple steatosis and in steatohepatitis (6.16+/-0.78 vs 5.69+/-0.49ng/ml). An inverse correlation was observed between adiponectin and homeostatic model assessment (HOMA) of insulin resistance (P = 0.008), while adiponectin did not correlate with serum transaminases and lipid values.

CONCLUSIONS

These data support a role for low circulating adiponectin in the pathogenesis of NAFLD and confirm the strict association between reduced adiponectin production by adipose tissue, NAFLD and insulin resistance.

Special considerations in the initiation and management of antiretroviral therapy in individuals coinfected with HIV and hepatitis C

BACKGROUND

Although hepatitis C (HCV) treatment efficacy has improved in recent years, the majority of HIV/HCV-coinfected individuals may not enjoy the full benefits of these treatments and appropriate HIV management is crucial. Evidence is accumulating regarding the impact of HIV/HCV coinfection on the response to, and safety and tolerability of, antiretroviral therapy (ART) in this population.

METHODS

Computerized, English-language literature searches of MEDLINE and PubMed databases (January 1985 to May 2004) for studies of HIV and HCV infection in humans to examine critically (a) the impact of HCV on the HIV virologic and immunologic response to ART; (b) the safety and tolerability of ART in coinfected individuals; and (c) the relationship between immune suppression and immune restoration on hepatic injury.

RESULTS

Three key messages emerged regarding the use of ART in HIV/HCV-coinfected individuals: (a) although HCV appeared to have no impact on HIV virologic response, the data are equivocal regarding immunologic response; (b) morbidities associated with HCV infection, such as insulin resistance, diabetes, mitochondrial dysfunction, and liver inflammation, are also associated toxicities of ART, and (c) both immune suppression and restoration can contribute to the onset and acceleration of HCV-related liver disease.

CONCLUSIONS

The CD4 cell count threshold for initiating ART in HIV/HCV-coinfected patients may be higher because of the impact of immune suppression and restoration on the onset of HCV-associated liver disease and the possibility of a blunted immune response to ART at lower CD4 cell counts. Further, overlapping morbidity between HCV-related mitochondrial and metabolic disease manifestations and ART toxicities warrant careful attention by clinicians.

Central obesity and elevated liver enzymes

Nonalcoholic fatty liver disease is commonly associated with obesity, a growing epidemic worldwide. A new large, population-based investigation has shown a statistically significant association between central adiposity and elevated liver enzymes. This finding adds to the growing research specifically linking central adiposity, and more specifically, visceral adiposity, with adverse health effects.

Postprandial insulin response and mitochondrial oxidation in obese men nutritionally treated to lose weight

Obesity, hyperglycemia, and insulin resistance have been associated to an oxidative mitochondrial dysfunction. The aim of this research was to evaluate the relation between carbohydrate metabolism and mitochondrial oxidation, as affected by the weight status and the weight loss induced by a calorie-restricted diet. Lean control men (BMI<25 kg/m2, n = 6) and obese men (BMI>30 kg/m2, n = 14), who were characterized as insulin resistant (n = 6) or insulin sensitive (n = 8) based on HOMA index values, participated in the trial. Plasma insulin levels and mitochondrial oxidation estimated by the 2-keto(1-13C)isocaproate breath test, were measured after ingestion of a test meal during 3 h. Obese subjects repeated the breath test protocol after a 10-week caloric restriction diet to lose weight. Postprandial insulin secretion tended to be marginally higher (P = 0.059) in both obese groups than in controls, while the rate of postprandial mitochondrial oxidation was markedly decreased (P = 0.019) in the obese subjects as compared with lean individuals. The nutritionally induced weight loss produced a rise in the postprandial oxidative process in volunteers initially considered as insulin resistant (P = 0.036), while no statistical differences in the insulin-sensitive obese (P = 0.241) were found. Interestingly, the percentage of oxidized tracer was inversely related to postprandial insulin secretion (r = -0.56; P = 0.001). In conclusion, these results support the hypothetized relation between carbohydrate metabolism and mitochondrial oxidation at a postprandial state in obese subjects, raising interest about mitochondria stimulation as a target in the therapy of obesity.

The wide spectrum of steatohepatitis: a report of four cases and a review of the literature

We report on four cases displaying the wide range of aetiological risk factors (presence or absence of family history of dyslipidaemia and cryptogenic cirrhosis, from subnormal body mass index through morbid obesity, from absent through hepatotoxic alcohol consumption), laboratory test results (from subnormal through elevated uric acid and ferritin values), ultrasonographic changes (from normal findings through 'bright liver' with or without attenuation of ultrasound beam and absence/presence of focal lesions), and histological severity of steatohepatitis (fibrosis appearing to be inversely related to the amount of liver fat but zone 3 accentuation of lesions and ballooning being observed in all cases). Cases illustrate the concepts of overlapping aetiologies of steatohepatitis (hepatitis C, diabetes and lipodystrophy); the relationships between cryptogenic cirrhosis, familial cirrhosis, non-alcoholic fatty liver disease and hepatocellular carcinoma; familial hypobetalipoproteinaemia as an aetiology of steatohepatitis; and alcoholic liver disease in the obese. These issues, which are worthy of future investigation, are reviewed.