An extended fatty liver index to predict non-alcoholic fatty liver disease.

BACKGROUND: In clinical practice, there is a strong interest in non-invasive markers of non-alcoholic fatty liver disease (NAFLD). Our hypothesis was that the fold-change in plasma triglycerides (TG) during a 2-h oral glucose tolerance test (fold-change TGOGTT) in concert with blood glucose and lipid parameters, and the rs738409 C>G single nucleotide polymorphism (SNP) in PNPLA3 might improve the power of the widely used fatty liver index (FLI) to predict NAFLD. METHODS: The liver fat content of 330 subjects was quantified by 1H-magnetic resonance spectroscopy. Blood parameters were measured during fasting and after a 2-h OGTT. A subgroup of 213 subjects underwent these measurements before and after 9 months of a lifestyle intervention. RESULTS: The fold-change TGOGTT was closely associated with liver fat content (r=0.51, P<0.0001), but had less power to predict NAFLD (AUROC=0.75) than the FLI (AUROC=0.79). Not only was the fold-change TGOGTT independently associated with liver fat content and NAFLD, but so also were the 2-h blood glucose level and rs738409 C>G SNP in PNPLA3. In fact, a novel index (extended FLI) generated from these and the usual FLI parameters considerably increased its power to predict NAFLD (AUROC=0.79-0.86). The extended FLI also increased the power to predict changes in liver fat content with a lifestyle intervention (n=213; standardized beta coefficient: 0.23-0.29). CONCLUSION: This study has provided novel data confirming that the OGTT-derived fold-change TGOGTT and 2-h glucose level, together with the rs738409 C>G SNP in PNPLA3, allow calculation of an extended FLI that considerably improves its power to predict NAFLD.

Diagnostic performance of FibroTest, SteatoTest and ActiTest in patients with NAFLD using the SAF score as histological reference.

BACKGROUND: Blood tests of liver injury are less well validated in non-alcoholic fatty liver disease (NAFLD) than in patients with chronic viral hepatitis. AIMS: To improve the validation of three blood tests used in NAFLD patients, FibroTest for fibrosis staging, SteatoTest for steatosis grading and ActiTest for inflammation activity grading. METHODS: We pre-included new NAFLD patients with biopsy and blood tests from a single-centre cohort (FibroFrance) and from the multicentre FLIP consortium. Contemporaneous biopsies were blindly assessed using the new steatosis, activity and fibrosis (SAF) score, which provides a reliable and reproducible diagnosis and grading/staging of the three elementary features of NAFLD (steatosis, inflammatory activity) and fibrosis with reduced interobserver variability. We used nonbinary-ROC (NonBinAUROC) as the main endpoint to prevent spectrum effect and multiple testing. RESULTS: A total of 600 patients with reliable tests and biopsies were included. The mean NonBinAUROCs (95% CI) of tests were all significant (P < 0.0001): 0.878 (0.864-0.892) for FibroTest and fibrosis stages, 0.846 (0.830-0.862) for ActiTest and activity grades, and 0.822 (0.804-0.840) for SteatoTest and steatosis grades. FibroTest had a higher NonBinAUROC than BARD (0.836; 0.820-0.852; P = 0.0001), FIB4 (0.845; 0.829-0.861; P = 0.007) but not significantly different than the NAFLD score (0.866; 0.850-0.882; P = 0.26). FibroTest had a significant difference in median values between adjacent stage F2 and stage F1 contrarily to BARD, FIB4 and NAFLD scores (Bonferroni test P < 0.05). CONCLUSIONS: In patients with NAFLD, SteatoTest, ActiTest and FibroTest are non-invasive tests that offer an alternative to biopsy, and they correlate with the simple grading/staging of the SAF scoring system across the three elementary features of NAFLD: steatosis, inflammatory activity and fibrosis.

PNPLA3 rs738409 I748M is associated with steatohepatitis in 434 non-obese subjects with hepatitis C.

BACKGROUND: The PNPLA3/Adiponutrin rs738409 C/G single nucleotide polymorphism is associated with the severity of steatosis, steatohepatitis and fibrosis in patients with non-alcoholic fatty liver disease, as well as the severity of steatosis and fibrosis in patients with chronic hepatitis C (CHC). AIM: To test in genotype 1(G1)-CHC patients, the putative association between the PNPLA3 variant and histological features of steatohepatitis, as well as their impact on the severity of fibrosis. METHODS: Four hundred and thirty-four consecutively biopsied Caucasian G1-CHC patients were genotyped for PNPLA3 rs738409, its effect evaluated by using an additive model. Histological features of steatohepatitis in CHC were assessed using the Bedossa classification. Hepatic expression of PNPLA3 mRNA was evaluated in 63 patients. RESULTS: The prevalence of steatohepatitis increased from 16.5% in patients with PNPLA3 CC, to 23.2% in CG and 29.2% in the GG genotype (P = 0.02). By multiple logistic regression, PNPLA3 genotype (OR 1.54, 95% CI 1.03-2.30, P = 0.03), together with age (OR 1.03, 95% CI 1.00-1.05, P = 0.02), BMI ≥ 30 (OR 2.06, 95% CI 1.04-4.10, P = 0.03) and homoeostasis model assessment (HOMA, OR 1.18, 95% CI 1.04-1.32, P = 0.006) were independently linked to steatohepatitis. When stratifying for obesity, PNPLA3 was associated with NASH in non-obese patients only (12.0% in CC vs. 18.3% in CG vs. 27.3% in GG, P = 0.01), including after correction for metabolic confounders (OR 2.06, 95% CI 1.26-3.36, P = 0.004). We showed an independent association between steatohepatitis (OR 2.05, 95% CI 1.05-4.02, P = 0.003) and severe fibrosis. Higher liver PNPLA3 mRNA was associated both with the severity of steatosis (adjusted P = 0.03) and steatohepatitis after adjusting for gender, age, BMI and HOMA (P = 0.002). CONCLUSION: In patients with genotype 1 hepatitis C, the PNPLA3 G variant is associated with a higher risk of steatosis severity and steatohepatitis, particularly among non-obese subjects.

HCV genotype 3 and squamous cell carcinoma antigen (SCCA)-IgM are independently associated with histological features of NASH in HCV-infected patients.

Nonalcoholic steatohepatitis (NASH) enhances the risk of progressive liver disease. In chronic hepatitis C (CHC), liver steatosis is frequent, especially in genotype 3, but its clinical significance is debated. As squamous cell carcinoma antigen (SCCA)-IgM has been associated with advanced liver disease and risk of tumour development, we evaluated its occurrence in CHC and the possible relation with NASH at liver biopsy. Using a validated ELISA, serum SCCA-IgM was measured in 91 patients with CHC at the time of liver biopsy performed before antiviral treatment, at the end of treatment and 6 months thereafter, and in 93 HCV-negative patients with histological diagnosis of nonalcoholic fatty liver disease, as controls. SCCA-IgM was detected in 33% of CHC patients and in 4% of controls. This biomarker was found more elevated in CHC patients with histological NASH, and at multivariate analysis, SCCA-IgM and HCV genotype 3 were independently associated with NASH [OR (95% CI): 6.94 (1.21-40) and 27.02 (4.44-166.6)]. As predictors of NASH, HCV genotype 3 and SCCA-IgM had a specificity and a sensitivity of 97% and 44%, and of 95% and 27%, respectively. PPV and NPV were 80% and 86% for HCV genotype 3 vs 73% and 72% for SCCA-IgM. In patients with sustained virologic response to therapy, SCCA-IgM levels decreased significantly, while these remained unchanged in nonresponders. In conclusion, SCCA-IgM is detectable in one-third of patients with CHC and significantly correlates with histological NASH.

Non-alcoholic steatohepatitis (NASH) and oral lichen planus: a rare occurrence.

Oral lichen planus (OLP) is frequently associated with hepatitis C virus infection but uncommonly with other causes of liver disorder. The authors report the case of a 41-year-old male patient with a clinical and histological diagnosis of OLP who presented with a marked alteration of the transaminase values, with no signs of past or present HBV, HCV, HGV or TTV infection. The patient did not consume alcohol and no exposure to hepatotoxic substances was reported. All autoantibodies were negative. Hepatic fine needle biopsy showed macrovesicular steatosis with a slight chronic portal inflammatory infiltrate and signs of siderosis. Iron metabolism was slightly altered. Genetic tests showed a heterozygotic mutation for hereditary haemochromatosis gene (HLA-H C282Y) but not for HLA-H63D. The patient presented slight insulin resistance but had normal glycaemic values. The results are consistent with a diagnosis of non-alcoholic steatohepatitis (NASH). This is the first reported case of NASH associated with OLP.

Venesection for non-alcoholic fatty liver disease unresponsive to lifestyle counselling--a propensity score-adjusted observational study.

BACKGROUND/AIM: To test the short-term clinical usefulness of venesection associated with lifestyle counselling as against counselling alone on insulin resistance and liver enzymes in subjects with non-alcoholic fatty liver disease (NAFLD), using a propensity score approach. METHODS: We carried out a 6- to 8-month observational analysis of 198 NAFLD patients in three Italian referral centres (79 venesection and 119 counselling alone). Insulin resistance was measured by the homeostasis model assessment (HOMA) method. Logistic regression was used to identify factors associated with normal HOMA and normal alanine aminotransferase (ALT) at the end of observation. The results were adjusted for the propensity score to be enrolled in the venesection programme, based on clinical and laboratory data, including common HFE polymorphisms and liver biopsy (available in 161 cases). RESULTS: After adjustment for propensity and changes in BMI, venesection was significantly associated with normal HOMA [all cases: odds ratio (OR) 3.00; 95% confidence interval (CI) 1.51-5.97; cases with histology: OR 2.29; 95% CI 1.08-4.87] and ALT within normal limits (all cases: OR 2.56; 95% CI 1.29-5.10; cases with histology: OR 2.81; 95% CI 1.20-5.24). The results were confirmed in an analysis of 57 pairs matched for propensity, where venesection similarly increased the probability of normal HOMA (OR 3.27; 95% CI 1.16-7.84) and normal ALT (OR 5.60; 95% CI 2.09-15.00). Similar data were obtained in the subset of cases with normal basal ferritin (<350 ng/ml). CONCLUSION: Iron depletion by venesection favours the normalization of insulin resistance and raised liver enzymes in non-haemochromatosis patients with NAFLD.

Insulin resistance in nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) refers to a spectrum of liver damage ranging from simple steatosis to nonalcoholic steatohepatitis (NASH), advanced fibrosis and cirrhosis. NAFLD is considered the hepatic component of the metabolic syndrome and insulin resistance represents its pathophysiological hallmark. Insulin resistance in NAFLD is characterized by reduced whole-body, hepatic, and adipose tissue insulin sensitivity. The mechanism(s) underlying the accumulation of fat in the liver may include excess dietary fat, increased delivery of free fatty acids to the liver, inadequate fatty acid oxidation, and increased de novo lipogenesis. Liver fat is highly correlated with all the components of the metabolic syndrome, independent of obesity, and NAFLD may increase the risk of type 2 diabetes and atherosclerosis. Overproduction of glucose, very low-density lipoproteins, C-reactive protein and coagulation factors by the fatty liver could contribute to the excess risk of cardiovascular disease. The reason(s) why some patients will develop NASH are poorly understood. Circulating free fatty acids may be cytotoxic by inducing lipid peroxidation and hepatocyte apoptosis. Insulin resistance is often associated with chronic low-grade inflammation, and numerous mediators released from immune cells and adipocytes may contribute liver damage and liver disease progression. Understanding the molecular mediators of liver injury would promote the development of mechanism-based therapeutic interventions. This article briefly summarizes the recent advances in our understanding of the relationship between NAFLD/NASH, insulin resistance and the metabolic syndrome.

Practice guidelines for the diagnosis and management of nonalcoholic fatty liver disease. A decalogue from the Italian Association for the Study of the Liver (AISF) Expert Committee.

We report the evidence-based Italian Association for the Study of Liver guidelines for the appropriate diagnosis and management of patients with nonalcoholic fatty liver disease in clinical practice and its related research agenda. The prevalence of nonalcoholic fatty liver disease varies according to age, gender and ethnicity. In the general population, the prevalence of nonalcoholic fatty liver disease is about 25% and the incidence is of two new cases/100 people/year. 2-3% of individuals in the general population will suffer from nonalcoholic steatohepatitis. Uncomplicated steatosis will usually follow a benign course. Individuals with nonalcoholic steatohepatitis, however, have a reduced life expectancy, mainly owing to vascular diseases and liver-related causes. Moreover, steatosis has deleterious effects on the natural history of HCV infection. Nonalcoholic fatty liver disease is usually diagnosed in asymptomatic patients prompted by the occasional discovery of increased liver enzymes and/or of ultrasonographic steatosis. Medical history, complete physical examination, etiologic screening of liver injury, liver biochemistry tests, serum lipids and insulin sensitivity tests should be performed in every patient. Occult alcohol abuse should be ruled out. Ultrasonography is the first-line imaging technique. Liver biopsy, the gold standard in diagnosis and prognosis of nonalcoholic fatty liver disease, is an invasive procedure and its results will not influence treatment in most cases but will provide prognostic information. Assessment of fibrosis by composite scores, specific laboratory parameters and transient elastography might reduce the number of nonalcoholic fatty liver disease patients requiring liver biopsy. Dieting and physical training reinforced by behavioural therapy are associated with improved nonalcoholic fatty liver disease. Diabetes and the metabolic syndrome should be ruled out at timed intervals in nonalcoholic fatty liver disease. Nonalcoholic steatohepatitis patients should undergo periodic evaluation of cardiovascular risk and of advancement of their liver disease; those with nonalcoholic steatohepatitis-cirrhosis should be evaluated for early diagnosis of hepatocellular carcinoma.

Which treatment for nonalcoholic fatty liver disease?

Subjects with nonalcoholic fatty liver disease are at risk of progressive liver failure. Lifestyle changes including weight-loss strategies and increased physical activity remain the first-line approach, but a few pharmacological treatments have also been successfully tested. Several drugs improve biochemistry, only a few improve histology; in all cases, the results were not sustained after treatment stop. Pharmacological treatment is not so far indicated outside controlled clinical trials with histological outcomes.

Use of corticosteroids, immunomodulators, and infliximab at a third-level Day-Hospital Service of Gastro-Hepatology.

AIM: Third-level Day-Hospital Services of Gastro-Hepatology are likely to recruit patients with an increased disease severity. The burden of request for immunomodulation drugs is presently unclear. METHODS: The charts of 1 012 consecutive patients who underwent day-hospital admission were reviewed. Among them, 975 were admitted for several reasons (percutaneous liver biopsies, abdominal fluid aspirations, infiltrations of hepatic nodules, gastrointestinal endoscopies with specific treatments). Data of the remaining 37 patients were elaborated. RESULTS: Of them, 31 (83%) suffered from ulcerative colitis (UC) or Crohn's disease (CD) (17 and 14, respectively) and 6 from autoimmune type 1 hepatitis (AIH). Of the 14 non-operated UC patients, 12 were taking azathioprine (AZA) and 2 infliximab (IFX). Among CD patients, the majority received AZA (N=6) or IFX (N=6). Of the AIH patients, 5 were treated with AZA and 2 had also cyclosporine. Overall, corticosteroids (32%) and IFX (21%) ranked first and second among the induction drugs, and AZA ranked first (62%) as maintenance option. Of the 4 CD patients under IFX treatment, 2 were switched to leukapheresis for incomplete response, the third one developed thrombotic complications, and the last one achieved disease remission after 12 months. Of the 2 cases of UC, one lost response soon and was colectomized, the other is maintaining moderately active disease, requiring scheduled injections every 8 weeks. CONCLUSION: Despite the caution imposed by the very small numbers, this analysis confirms that the potent available options are difficult to be correctly positioned in the therapeutic algorithm of inflammatory bowel disease.

Histological progression of non-alcoholic fatty liver disease: a critical reassessment based on liver sampling variability.

BACKGROUND: In non-alcoholic fatty liver disease, histological lesions display a significant sampling variability that is ignored when interpreting histological progression during natural history or therapeutic interventions. AIM: To provide a method taking into account sampling variability when interpreting crude histological data, and to investigate how this alters the conclusions of available studies. METHODS: Natural history studies detailing histological progression and therapeutic trials were compared with the results of a previously published sampling variability study. RESULTS: Natural history studies showed an improvement in steatosis, which was significantly higher than expected from sampling variability (47% vs. 8%, P < 0.0001). In contrast, no study showed a change in activity grade or ballooning higher than that of sampling variability. There was only a marginal effect on fibrosis with no convincing demonstration of a worsening of fibrosis, a conclusion contrary to what individual studies have claimed. Some insulin sensitizing drugs and anti-obesity surgery significantly improved steatosis, while most did not significantly impact on fibrosis or activity. CONCLUSIONS: Sampling variability of liver biopsy is an overlooked confounding factor that should be considered systematically when interpreting histological progression in patients with non-alcoholic fatty liver disease.

Non-alcoholic steatohepatitis and cancer.

Hepatocellular carcinoma (HCC) is part of the natural history of non-alcoholic steatohepatitis (NASH). A significant proportion of people who have cryptogenic cirrhosis develop HCC. NASH-related cirrhosis carries a substantial risk for early HCC development. Diagnosis of HCC often is made at first referral; the tumor usually is large with multiple localizations. Patients who have obesity or diabetes are at risk for HCC and a variety of cancers. Given the epidemic of obesity and diabetes, the incidence of NASH-related HCC is expected to increase. In addition to developing new diagnostic tools and pharmacologic therapies, efforts should be directed at preventing non-alcoholic fatty liver disease.

Post-load insulin resistance is an independent predictor of hepatic fibrosis in virus C chronic hepatitis and in non-alcoholic fatty liver disease.

BACKGROUND: Insulin resistance is a significant risk factor for hepatic fibrosis in patients with both non-alcoholic fatty liver disease (NAFLD) and chronic hepatitis C (CHC), either directly or by favouring hepatic steatosis. Several methods are available to assess insulin resistance, but their impact on this issue has never been evaluated. AIMS: To determine the relative contribution of steatosis, metabolic abnormalities and insulin resistance, measured by different basal and post-load parameters, to hepatic fibrosis in CHC and in NAFLD patients. METHODS: In 90 patients with CHC and 90 pair-matched patients with NAFLD, the degree of basal insulin resistance (by the homeostasis model assessment, (HOMA)) and post-load insulin sensitivity (by the oral glucose insulin sensitivity (OGIS) index) was assessed, together with the features of the metabolic syndrome according to Adult Treatment Panel III definition. Data were correlated with hepatic histopathology. RESULTS: The prevalence of basal insulin resistance (HOMA values >75th percentile of normal) was 23.3% in CHC patients and 57.8% in NAFLD, but it increased to 28.8 and 67.8% when measured by post-load insulin resistance (OGIS <25th percentile). In a multivariate model, after adjustment for age, gender and body mass index, OGIS was a predictor of severe fibrosis in CHC and in NAFLD patients, independently of steatosis. An OGIS value below the cut-off of the 25th percentile increased the likelihood ratio of severe fibrosis by a factor of 1.5-2 and proved to be a more sensitive and generally more specific test than HOMA-R for the identification of subjects with severe fibrosis both in NAFLD and in CHC. CONCLUSIONS: Post-load insulin resistance (OGIS <9.8 mg/kg/min) is associated with severe hepatic fibrosis in both NAFLD and CHC patients, and may help identify subjects at risk of progressive disease.

Fatal liver failure following food supplements during chronic treatment with montelukast.

High aminotransferases and prolonged prothrombin time on entering our liver unit were revealing parenchymal collapse for this 45-year-old obese woman; treatment failure led her to death. Autoimmunity, paracetamol use, alcoholism, and Wilson's disease were all excluded as causes. Because of chronic asthma, she had been receiving a leukotriene receptor antagonist (montelukast) for 5 years before the current presentation; 1 week before onset she had had 1 week of treatment with two dietary supplements for weight control; one of these included Garcinia Cambogia, a possible cause of two recent cases of hepatitis in the USA; in addition, both formulas contained a citrus derivative that interferes cytochrome functions. We speculate on a causal relationship between the assumption of the additives and the fatal hepatitis and envisage a synergy between the additives and montelukast, which per se has well been studied as a hepatotoxic drug. Despite the speculative nature of this presentation, we believe the warning may serve to focus attention on the uncontrolled escalation of food additives going on in these days.

Steatosis and hepatocellular carcinoma risk.

The natural history of Non Alcoholic Fatty Liver Disease (NAFLD) is difficult to assess, but there is mounting evidence that patients with NAFLD may eventually develop cirrhosis and hepatocellular carcinoma (HCC). Retrospective, case-control studies have shown that features suggestive of Non Alcoholic SteatoHepatitis (NASH) are more frequent in HepatoCellular Carcinoma (HCC) complicating cryptogenic cirrhosis than in matched HCC patients with known etiology. In the only available prospective cohort study, there is the absence of HCC as a complication of NASH-associated cirrhosis after a mean follow up of 7 years (median 5 years). However prospective NASH studies are too short to exclude late complications. In fact the average lenght of cirrhosis before the diagnosis of HCC was 16 years. The prevalence of risk factors associated with NASH can account for the increasing incidence of cryptogenic cirrhosis and subsequent HCC. Obesity and diabetes per se are significantly associated with the development of HCC. In particular diabetes was found to be a risk factor for HCC independent of age, gender, and race. Chronic hyperinsulinaemia and insulin-like growth factor 1 (IGF-1) might be involved in hepato-carcinogenesis. Exposure to physiological insulin concentrations stimulate proliferation of human and rat hepatoma cell line. Changes in the expression pattern of IGF-system components has been observed in patients with HCC, in human hepatoma cell lines and in their conditioned culture medium.

Review article: steatosis, the metabolic syndrome and cancer.

The incidence of hepatocellular carcinoma is increasing, but the temporal changes of risk factors remain unclear. A significant proportion of hepatocellular carcinoma (7-30%) develops in cryptogenic cirrhosis, and may represent the most worrisome complication of non-alcoholic steatohepatitis. Non-alcoholic steatohepatitis is tightly related to insulin resistance and several features of the metabolic syndrome, i.e obesity, type 2 diabetes and dyslipidaemia. Nearly two-thirds of adults in the United States and an increasing percentage of the population worldwide are overweight or obese. Diabetes prevalence is increasing as well. The rising prevalence of risk factors associated with non-alcoholic steatohepatitis can partially account for the increasing incidence of cryptogenic cirrhosis and subsequent hepatocellular carcinoma. Moreover, recent evidence demonstrates that both obesity and diabetes are per se associated with an increased cancer risk. Large prospective studies show a significant association with obesity for several cancers, including cancers of the colon, female breast, endometrium, kidney, oesophagus and liver (hepatocellular carcinoma). Type 2 diabetes is also related with increased risks of colon, endometrial, kidney, pancreatic cancer and hepatocellular carcinoma. In western countries, the insulin resistance syndrome is emerging as a risk factor for a wide variety of cancers, including hepatocellular carcinoma.

Insulin resistance in non-diabetic patients with non-alcoholic fatty liver disease: sites and mechanisms.

AIMS/HYPOTHESIS: Non-alcoholic fatty liver disease (NAFLD) has been associated with the metabolic syndrome. However, it is not clear whether insulin resistance is an independent feature of NAFLD, and it remains to be determined which of the in vivo actions of insulin are impaired in this condition. METHODS: We performed a two-step (1.5 and 6 pmol min(-1) kg(-1)) euglycaemic insulin clamp coupled with tracer infusion ([6,6-2H2]glucose and [2H5]glycerol) and indirect calorimetry in 12 non-obese, normolipidaemic, normotensive, non-diabetic patients with biopsy-proven NAFLD and six control subjects. RESULTS: In NAFLD patients, endogenous glucose production (basal and during the clamp) was normal; however, peripheral glucose disposal was markedly decreased (by 30% and 45% at the low and high insulin doses, respectively, p<0.0001) at higher plasma insulin levels (p=0.05), due to impaired glucose oxidation (p=0.003) and glycogen synthesis (p<0.001). Compared with control subjects, glycerol appearance and lipid oxidation were significantly increased in NAFLD patients in the basal state, and were suppressed by insulin to a lesser extent (p<0.05-0.001). The lag phase of the in vitro copper-catalysed peroxidation of LDL particles was significantly shorter in the patients than in the control subjects (48+/-12 vs 63+/-13 min, p<0.04). Lipid oxidation was significantly related to endogenous glucose production, glucose disposal, the degree of hepatic steatosis, and LDL oxidisability. CONCLUSIONS/INTERPRETATION: Insulin resistance appears to be an intrinsic defect in NAFLD, with the metabolic pattern observed indicating that adipose tissue is an important site.