Comparison of noninvasive markers of fibrosis in patients with nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease in 2015

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.

Cardiovascular risk across the histological spectrum and the clinical manifestations of non-alcoholic fatty liver disease: An update

Non-alcoholic fatty liver disease (NAFLD) is considered to be an independent cardiovascular disease (CVD) risk factor. However, simple steatosis has a benign clinical course without excess mortality. In contrast, the advanced form of NAFLD, non-alcoholic steatohepatitis (NASH) with liver fibrosis increases mortality by approximately 70%, due to an increase in CVD mortality by approximately 300%. Chronic kidney disease (CKD) may be caused by NAFLD/NASH and it substantially increases CVD risk, especially in the presence of type 2 diabetes mellitus. Moreover, CKD may trigger NAFLD/NASH deterioration in a vicious cycle. NAFLD/NASH is also related to increased arterial stiffness (AS), an independent CVD risk factor that further raises CVD risk. Diagnosis of advanced liver fibrosis (mainly by simple non-invasive tests), CKD, and increased AS should be made early in the course of NAFLD and treated appropriately. Lifestyle measures and statin treatment may help resolve NAFLD/NASH and beneficially affect the CVD risk factors mentioned above.

Prevalence and incidence of liver dysfunction and assessment of biomarkers of liver disease in HIV-infected Asian children

BACKGROUND

We determined the prevalence and incidence of liver dysfunction before and after initiation of combination antiretroviral therapy (cART) in the TREAT Asia Pediatric HIV Observational Database.

METHODS

Data from children initiated on cART between 2 and 18 years of age with baseline alanine aminotransferase (ALT) available before and at least once after cART initiation in TREAT Asia Pediatric HIV Observational Database between 2008 and 2012 were analyzed. Prevalence and incidence of liver dysfunction and biomarkers including the aspartate aminotransferase to platelet ratio index and FIB4 index (a noninvasive panel to stage liver disease) were assessed.

RESULTS

Data from 1930 children were included. Their median age was 6.9 years; 49% were male; 98% were perinatally infected and 94% were initiated on non-nucleoside reverse transcriptase-based cART regimens. Before cART, the prevalence of ALT ≥3 times the upper limit of normal (×ULN) was 5.8%. There were 8.5% of children with aspartate aminotransferase to platelet ratio index >1.5 (suggestive of liver fibrosis) and 2.7% with FIB4 index >1.3 (predictive of possible cirrhosis). Among the 1143 cases with normal baseline ALT (≤1×ULN), the incidence of ALT 3×ULN after cART was 1.19 of 1000 person-months (95% confidence interval: 0.93-1.51). Two of 350 with available tests (0.6%) met Hy's law (ALT >3×ULN and total bilirubin >2×ULN). By multivariate analysis, baseline hemoglobin <7.5 g/dL was a predictor of ALT >3×ULN, whereas age 5-9 years at cART initiation was protective for liver dysfunction.

CONCLUSIONS

We demonstrated a low prevalence and incidence of liver dysfunction before and after cART initiation in children with normal baseline chemistries. In this population facing life-long cART, prospective surveillance for emergence of liver disease is warranted.

Comparative diagnostic accuracy of magnetic resonance elastography vs. eight clinical prediction rules for non-invasive diagnosis of advanced fibrosis in biopsy-proven non-alcoholic fatty liver disease: a prospective study

BACKGROUND

Two-dimensional magnetic resonance elastography (2D-MRE) is an advanced magnetic resonance method with high diagnostic accuracy for predicting advanced fibrosis in non-alcoholic fatty liver disease (NAFLD) patients. However, no prospective, head-to-head comparisons between 2D-MRE and clinical prediction rules (CPRs) have been performed in patients with biopsy-proven NAFLD.

AIM

To compare the diagnostic utility of 2D-MRE against that of eight CPRs (AST:ALT ratio, APRI, BARD, FIB-4, NAFLD Fibrosis Score, Bonacini cirrhosis discriminant score, Lok Index and NASH CRN model) for predicting advanced fibrosis in a prospective cohort with paired liver biopsy as the gold standard.

METHODS

This is a cross-sectional analysis of a prospective study of 102 patients (58.8% women) with biopsy-proven NAFLD, 2D-MRE and clinical research assessment within 90 days of biopsy. Receiver operating characteristic (ROC) analysis was performed to assess the performance of 2D-MRE and CPRs for predicting advanced fibrosis.

RESULTS

The mean (±s.d.) age and BMI were 51.3 (±14.0) years and 31.7 (±5.5) kg/m(2) respectively. 48, 26, 9, 13 and 6 patients had stage 0, 1, 2, 3 and 4 fibrosis respectively. The area under ROC curve (AUROC) was 0.957 for 2D-MRE and between 0.796 and 0.861 for the CPRs. FIB-4 was the best-performing CPR at predicting advanced fibrosis with AUROC of 0.861. In head-to-head comparisons using the DeLong test, 2D-MRE had significantly better AUROC (P < 0.05) than each CPR for predicting advanced fibrosis.

CONCLUSION

Compared to clinical prediction rules, 2D-MRE provides significantly higher accuracy for the diagnosis of advanced fibrosis in NAFLD patients.

Nonalcoholic fatty liver disease and type 2 diabetes: common pathophysiologic mechanisms

Nonalcoholic fatty liver disease (NAFLD) is an independent risk factor for advanced liver disease, type 2 diabetes (T2DM), and cardiovascular diseases. The prevalence of NAFLD in the general population is around 30 %, but it is up to three times higher in those with T2DM. Among people with obesity and T2DM, the NAFLD epidemic also is worsening. Therefore, it is important to identify early metabolic alterations and to prevent these diseases and their progression. In this review, we analyze the pathophysiologic mechanisms leading to NAFLD, particularly, those common to T2DM, such as liver and muscle insulin resistance. However, it is mainly adipose tissue insulin resistance that results in increased hepatic de novo lipogenesis, inflammation, and lipotoxicity. Although genetics predispose to NAFLD, an unhealthy lifestyle, including high-fat/high-sugar diets and low physical activity, increases the risk. In addition, alterations in gut microbiota and environmental chemical agents, acting as endocrine disruptors, may play a role.

Composite prognostic models across the non-alcoholic fatty liver disease spectrum: Clinical application in developing countries

Heterogeneity in clinical presentation, histological severity, prognosis and therapeutic outcomes characteristic of non-alcoholic fatty liver disease (NAFLD) necessitates the development of scientifically sound classification schemes to assist clinicians in stratifying patients into meaningful prognostic subgroups. The need for replacement of invasive liver biopsies as the standard method whereby NAFLD is diagnosed, graded and staged with biomarkers of histological severity injury led to the development of composite prognostic models as potentially viable surrogate alternatives. In the present article, we review existing scoring systems used to (1) confirm the presence of undiagnosed hepatosteatosis; (2) distinguish between simple steatosis and NASH; and (3) predict advanced hepatic fibrosis, with particular emphasis on the role of NAFLD as an independent cardio-metabolic risk factor. In addition, the incorporation of functional genomic markers and application of emerging imaging technologies are discussed as a means to improve the diagnostic accuracy and predictive performance of promising composite models found to be most appropriate for widespread clinical adoption.

Validation of aspartate aminotransferase to platelet ratio for diagnosis of liver fibrosis and prediction of postoperative prognosis in infants with biliary atresia

AIM: To validate the value of aspartate aminotransferase to platelet ratio index (APRI) in assessment of liver fibrosis and prediction of postoperative prognosis of biliary atresia (BA) infants from Mainland China.

METHODS: Medical records of 153 BA infants who were hospitalized from January 2010 to June 2013 were reviewed. The efficacy of APRI for diagnosis of liver fibrosis was assessed using the receiver operator characteristic (ROC) curve compared to the pathological Metavir fibrosis score of the liver wedge specimens of 91 BA infants. The prognostic value of preoperative APRI for jaundice persistence, liver injury, and occurrence of cholangitis within 6 mo after KP was studied based on the follow-up data of 48 BA infants.

RESULTS: APRI was significantly correlated with Metavir scores (r_s = 0.433; P < 0.05). The mean APRI value was 0.76 in no/mild fibrosis group (Metavir score F0-F1), 1.29 in significant fibrosis group (F2-F3), and 2.51 in cirrhosis group (F4) (P < 0.001). The area under the ROC curve (AUC) of APRI for diagnosing significant fibrosis and cirrhosis was 0.75 (P < 0.001) and 0.81 (P = 0.001), respectively. The APRI cut-off of 0.95 was 60.6% sensitive and 76.0% specific for significant fibrosis diagnosis, and a threshold of 1.66 was 70.6% sensitive and 82.7% specific for cirrhosis. The preoperative APRI in infants who maintained jaundice around 6 mo after KP was higher than that in those who did not (1.86 ± 2.13 vs 0.87 ± 0.48, P < 0.05). The AUC of APRI for prediction of postoperative jaundice occurrence was 0.67. A cut-off value of 0.60 showed a sensitivity of 66.7% and a specificity of 83.3% for the prediction of jaundice persistence. Preoperative APRI had no significant association with later liver injury or occurrence of cholangitis.

CONCLUSION: Our study demonstrated that APRI could diagnose significant liver fibrosis, especially cirrhosis in BA infants, and the elevated preoperative APRI predicts jaundice persistence after KP.

Evidence of NAFLD progression from steatosis to fibrosing-steatohepatitis using paired biopsies: implications for prognosis and clinical management

BACKGROUND AND AIMS

There remains uncertainty about the natural history of non-alcoholic fatty liver disease (NAFLD). The spectrum of NAFLD includes non-alcoholic fatty liver (NAFL; steatosis without hepatocellular injury) and steatohepatitis (NASH; steatosis with hepatocyte ballooning degeneration±fibrosis). Our aim was to assess the histological severity of NAFLD in a cohort with serial biopsy data, and determine factors predicting progression.

METHODS

Patients with two liver biopsies more than a year apart were identified. Clinical and laboratory data were collected from the time of liver biopsy.

RESULTS

108 patients had serial biopsies (median interval 6.6years, range 1.3-22.6). 81 (75%) patients had NASH and 27 had NAFL. Overall, 45 (42%) patients had fibrosis progression, 43 (40%) had no change in fibrosis, while 20 (18%) had fibrosis regression. Importantly, no significant difference in the proportion exhibiting fibrosis progression was found between those with NAFL or NASH at index biopsy (37% vs. 43%, p=0.65). Progression to NASH was seen in 44% of patients with baseline NAFL. Of 10 patients with NAFL who had fibrosis progression, 3 progressed by 1 stage, 5 by 2 stages and 2 by 3 stages; all had NASH on follow-up biopsy. Of concern, 6 of 27 (22%) patients with baseline NAFL, reached stage 3 fibrosis at follow-up biopsy. Among the patients with NAFL, 80% of those having fibrosis progression were diabetic at the follow-up liver biopsy compared with 25% of non-progressors (p=0.005).

CONCLUSIONS

Contrary to current dogma, this study suggests that steatosis can progress to NASH and clinically significant fibrosis.

The combination of liver stiffness measurement and NAFLD fibrosis score improves the noninvasive diagnostic accuracy for severe liver fibrosis in patients with nonalcoholic fatty liver disease

BACKGROUND & AIMS

The accuracy of noninvasive tools for the diagnosis of severe fibrosis in patients with nonalcoholic fatty liver disease(NAFLD) in clinical practice is still limited. We aimed at assessing the diagnostic performance of combined noninvasive tools in two independent cohorts of Italian NAFLD patients.

METHODS

We analysed data from 321 Italian patients(179 Sicilian-training cohort, and 142 northern Italy-validation cohort) with an histological diagnosis of NAFLD. Severe fibrosis was defined as fibrosis ≥ F3 according to Kleiner classification. The APRI, AST/ALT, BARD, FIB-4, and NFS scores were calculated according to published algorithms. Liver stiffness measurement(LSM) was performed by FibroScan. Cut-off points of LSM, NFS and FIB-4 for rule-in or rule-out F3-F4 fibrosis were calculated by the reported formulas.

RESULTS

In the Sicilian cohort AUCs of LSM, NFS, FIB-4, LSM plus NFS, LSM plus FIB-4, and NFS plus FIB-4 were 0.857, 0.803, 0.790, 0.878, 0.888 and 0.807, respectively, while in the northern Italy cohort the corresponding AUCs were 0.848, 0.730, 0.703, 0.844, 0.850, and 0.733 respectively. In the training cohort, the combination of LSM plus NFS was the best performing strategy, providing false positive, false negative and uncertainty area rates of 0%,1.1% and 48% respectively. Similar results were obtained in the validation cohort with false positive, false negative and uncertainty area rates of 0%,7.3% and 40.8%.

CONCLUSIONS

The combination of LSM with NFS, two complementary, easy-to-perform, and widely available tools, is able to accurately diagnose or exclude the presence of severe liver fibrosis, also reducing of about 50-60% the number of needed diagnostic liver biopsies.

Non-invasive Testing for NASH and NASH with Advanced Fibrosis: Are We There Yet?

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent etiology of chronic liver disease in America. NAFLD can be broadly classified in two subtypes: nonalcoholic fatty liver (NAFL), which is generally considered a benign condition with negligible risk of progression to cirrhosis, and nonalcoholic steatohepatitis (NASH), which is generally considered to be progressive with substantial risk of progression to cirrhosis. Additionally, recent studies suggest the odds of liver mortality increases amongst NASH patients with advanced fibrosis (bridging fibrosis ± cirrhosis). Liver biopsy examination is the current gold standard to accurately discriminate between NAFL vs. NASH as well as diagnose advanced fibrosis. However, due to its invasive nature, risk of bleeding (and even rarely death), prohibitive cost, and sampling error, liver biopsies are imperfect for diagnosis and monitoring of NAFLD. As a result, noninvasive biomarkers that can accurately detect NASH and advanced fibrosis without biopsy are needed. This article will discuss the most novel noninvasive biomarkers in diagnosing NASH and advanced fibrosis.

Non-invasive methods for the diagnosis of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the commonest chronic liver disease and includes simple steatosis and nonalcoholic steatohepatitis (NASH). Since NASH progresses to cirrhosis more frequently and increases liver-related and cardiovascular disease risk substantially more than simple steatosis, there is a great need to differentiate the two entities. Liver biopsy is the gold standard for the diagnosis of NAFLD but its disadvantages, including the risk of complications and sampling bias, stress the need for developing alternative diagnostic methods. Accordingly, several non-invasive markers have been evaluated for the diagnosis of simple steatosis and NASH, including both serological indices and imaging methods. The present review summarizes the current knowledge on the role of these markers in the diagnosis of NAFLD. Current data suggest that ultrasound and the fibrosis-4 score are probably the most appealing methods for detecting steatosis and for distinguishing NASH from simple steatosis, respectively, because of their low cost and relatively high accuracy. However, currently available methods, both serologic and imaging, cannot obviate the need for liver biopsy for diagnosing NASH due to their substantial false positive and false negative rates. Therefore, the current role of these methods is probably limited in patients who are unwilling or have contraindications for undergoing biopsy.

Biomarkers in nonalcoholic fatty liver disease-the emperor has no clothes?

Fatty liver is present in over ten percentage of the world population and it is a growing public health problem. Nonalcoholic fatty liver disease (NAFLD) is not a single disease, but encompasses a spectrum of diseases of different etiologies. It is difficult to find highly specific and sensitive diagnostic biomarkers when a disease is very complex. Therefore, we should aim to find relevant prognostic markers rather than accurate diagnostic markers which will help to minimize the frequency of liver biopsies to evaluate disease progression. There are several biomarker panels commercially available, however, there is no clear evidence that more sophisticated panels are better compared to simple criteria such as, presence of diabetes over five years, metabolic syndrome, obesity, obstructive sleep apnea, aspartate transaminase/alanine transaminase (ALT) ratio > 0.8 or ferritin levels > 1.5 times normal in patients with over six month history of raised ALT and/or ultrasonological evidence of fat in the liver. Currently the biomarker panels are not a replacement for a liver biopsy. However the need and benefit of liver biopsy in NAFLD is questionable because there is no convincing evidence that biopsy and detailed staging of NAFLD improves the management of NAFLD and benefits the patient. After all there is no evidence based treatment for NAFLD other than management of lifestyle and components of “metabolic syndrome”.

Contemporary assessment of hepatic fibrosis

Newer noninvasive tests have begun to replace liver biopsy for staging purposes. The clinician must evaluate these tools and apply them to individual patients. None of these modalities give the exact same staging of fibrosis as a liver biopsy, but they are excellent tools for risk stratification. Still, it should be recognized that there are disease-specific issues with different utilizations and cutoffs for different clinical diseases. This article provides a framework for incorporating the use of serum biomarkers and elastography-based approaches to stage fibrosis into clinical practice. This review also covers recent developments in this rapidly advancing area.

Comparison of noninvasive scores for the detection of advanced fibrosis in patients with nonalcoholic fatty liver disease

BACKGROUND

The presence of advanced liver fibrosis portends a poor prognosis in nonalcoholic fatty liver disease (NAFLD). We aimed to compare the diagnostic performance of five noninvasive scores [aspartate aminotransferase/platelet ratio (APRI), BARD, FIB-4, NAFLD fibrosis score (NFSA), and FibroMeter] for the assessment of advanced stages of fibrosis (F ≥ 3) in patients with biopsy-proven NAFLD.

METHODS

APRI, BARD, FIB-4, NFSA, and FibroMeter scores were determined in 142 patients with NAFLD. The histopathological analysis of liver biopsies was considered the gold standard. Sensitivity and specificity were calculated for each noninvasive test using receiver operating characteristic (ROC) curve analysis, with a cut-off value of F ≥ 3 for advanced fibrosis. The diagnostic accuracies were assessed by measuring the area under the ROC curve (AUROC). The AUROCs for different noninvasive tests were compared using paired significance tests.

RESULTS

At histopathological examination, 40 patients (28.2%) had a fibrosis stage F0, 50 patients (35.2%) had F1, 22 patients (15.5%) had F2, 20 patients (14.1%) had F3, and 10 patients (7.0%) had F4. The sensitivity of APRI, BARD, FIB-4, NFSA, and FibroMeter scores for advanced fibrosis was 70.0, 73.3, 70.0, 66.7, and 66.7%, respectively, and the specificity was 74.5, 66.4, 71.8, 71.8, and 74.5%, respectively. No significant differences in terms of sensitivity and specificity were evident for the five noninvasive scores. Moreover, the AUROCs did not differ significantly for all scores.

CONCLUSION

Our study suggests that different noninvasive scores have similar accuracy for the diagnosis of advanced hepatic fibrosis in NAFLD.

Clinical features of hepatocellular carcinoma associated with nonalcoholic fatty liver disease: a review of human studies

Most cases of hepatocellular carcinoma (HCC) in Japan develop in the background of chronic liver disease caused by hepatitis C virus (HCV). Recently, however, HCV-associated HCC has been shown to be decreasing, while non-B and non-C HCC (NBNC-HCC), which is negative for HCV and hepatitis B virus infection, has increased. The main cause of NBNC-HCC is alcoholic liver disease, but the recent increase of NBNC-HCC is thought to be due to an increase in patients with nonalcoholic fatty liver disease (NAFLD). Approximately 10% of NAFLD cases involve nonalcoholic steatohepatitis (NASH), and NASH can progress to liver cirrhosis and its associated complications such as HCC. There are no accurate data on the percentage of NASH-related HCC among all-cause HCC in Japan, because no large-scale investigation has been performed. However, the rate is thought to be about 3% of overall HCC, which is lower than that in the United States. The incidence of HCC in patients with NASH-related cirrhosis is thought to be 2% per year, which is lower than that in HCV-related cirrhosis. Risks for NASH-related HCC include advanced hepatic fibrosis, older age, and being male. NAFLD that includes NASH is associated with metabolic syndrome, which includes obesity and diabetes, and metabolic syndrome is a risk factor for HCC. Genetic factors and dietary patterns may also be related to NASH-related HCC. Thus, regular HCC surveillance, as performed for patients with viral chronic liver disease, is required for patients with NAFLD, and diagnostic markers are required for simple, rapid and specific detection of NASH-related HCC.

New discriminant score to predict the fibrotic stage of non-alcoholic steatohepatitis in Japan

Background and aim

Currently, non-alcoholic steatohepatitis (NASH) can only be diagnosed histopathologically. Our objective was to establish a new scoring system for the fibrotic stage of NASH.

Methods

We enrolled 139 patients with histologically proven NASH and divided them into two groups to construct (n = 90) and validate (n = 49) a fibrotic score for NASH (FSN). We used 17 variables and their natural logarithmic transformations in the multivariate analysis. To assess the accuracy of the FSN in determining NASH advanced fibrosis (stages 3–4), we compared various fibrotic scores for NASH.

Results

In the construct group, multivariate regression analysis ultimately obtained the following function: z = 1.022 × ln (type IV collagen 7S) (ng/mL) − 0.00680 × (platelet count) (×10⁹/L) + 1.925 × ln (AST) (IU/L) − 1.239 × ln (ALT) (IU/L) + 0.249. Median values of the FSN for stages 1, 2, 3 and 4 were 1.87, 2.14, 3.26 and 3.89, respectively. The multiple regression coefficient and coefficient of determination were 0.70 and 0.46, respectively. In the validation group, the median value was 2.00, 2.83, 3.08 and 4.37 in each stage. With regard to the utility of the FSN for predicting advanced fibrosis of NASH (stage ≥3), the area under the receiver operating characteristic curves (AUROC), 0.909 (95 % CI 0.847–0.970, p < 0.001), was higher than that for the other fibrotic scores (APRI, NAFLD fibrosis score, FIB-4 index, BARD score, NIKEI) in the construct group.

Conclusions

This simple scoring system accurately predicts fibrotic stage and discriminates patients with advanced fibrosis of NASH.

Republished: Non-alcoholic fatty liver disease: non-invasive investigation and risk stratification

Non-alcoholic fatty liver disease (NAFLD) encompasses a histological spectrum of liver disease, from simple steatosis through to cirrhosis. As the worldwide rates of obesity have increased, NAFLD has become the commonest cause of liver disease in many developed countries, affecting up to a third of the population. The majority of patients have simple steatosis that carries a relatively benign prognosis. However, a significant minority have non-alcoholic steatohepatitis, and have increased liver related and cardiovascular mortality. Identifying those at risk of progressive disease is crucial. Liver biopsy remains the gold standard investigation for assessing stage of disease but its invasive nature makes it impractical for widespread use as a prognostic tool. Non-invasive tools for diagnosis and disease staging are required, reserving liver biopsy for those patients where it offers clinically relevant additional information. This review discusses the non-invasive modalities available for assessing steatosis, steatohepatitis and fibrosis. We propose a pragmatic approach for the assessment of patients with NAFLD to identify those at high risk of progressive disease who require referral to specialist services.

Background of the FIB-4 index in Japanese non-alcoholic fatty liver disease

OBJECTIVE

We investigated the distribution and characteristics of the FIB-4 index of liver fibrosis in 1,441 Japanese men (age 50.7±10.2 years) and 304 women (age 53.9±10.3 years) who underwent comprehensive general health checkups and were identified as having non-alcoholic fatty liver disease. With respect to the FIB-4 index, differences according to sex, metabolic indices, and ultrasonic findings were investigated.

METHODS

Among 9,255 individuals who underwent comprehensive general health checkups, 2,750 (29.8%) were found to have mild fatty liver or fatty liver based on ultrasound findings. After excluding patients who consumed ≥150 g alcohol/week (818 individuals), those testing positive for hepatitis B surface antigens or hepatitis C virus antibody (184 individuals), and those for whom data were insufficient (three individuals), we investigated the FIB-4 indices in the remaining 1,745 subjects.

RESULTS

There were no sex differences in the FIB-4 index. A total of 1,370 patients (78.5%) exhibited a low cut-off index (COI) (<1.30), 357 (20.5%), exhibited an indeterminate COI (1.30-2.67), and 18 (1.0%) exhibited a high COI (>2.67). There were no associations between the FIB-4 index and the constituent factors of metabolic syndrome. In contrast, there was a significant difference in the ln FIB-4 index between the patients with and without mild fatty liver or fatty liver on ultrasound among men (0.006±0.43 and -0.092±0.39, p<0.001), but not women.

CONCLUSION

The FIB-4 index was is significantly lower in men, but not women, with fatty liver. The FIB-4 index must be calculated separately during medical checkups and evaluated in conjunction with ultrasound findings.

Noninvasive Assessment of Fibrosis in Patients with Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is prevalent in 20-25% of the general population and is associated with metabolic risk factors such as obesity, diabetes mellitus, and dyslipidemia. Histologically, NAFLD ranges from simple steatosis to nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. As NASH develops in only 10-15% of patients with NAFLD, it is not practical to biopsy all patients who present with NAFLD. Noninvasive fibrosis tests have been extensively developed recently and offer alternatives for staging fibrosis. Despite their increasing use, such tests cannot adequately differentiate simple steatosis from NASH. At present, such tests can be used as first line tests to rule out patients without advanced fibrosis and thus prevent unnecessary secondary care referrals in a significant number of patients. In this review we present the evidence for the use of noninvasive fibrosis tests in patients with NAFLD.

Non-invasive diagnosis of advanced fibrosis and cirrhosis

Liver cirrhosis is a common and growing public health problem globally. The diagnosis of cirrhosis portends an increased risk of morbidity and mortality. Liver biopsy is considered the gold standard for diagnosis of cirrhosis and staging of fibrosis. However, despite its universal use, liver biopsy is an invasive and inaccurate gold standard with numerous drawbacks. In order to overcome the limitations of liver biopsy, a number of non-invasive techniques have been investigated for the assessment of cirrhosis. This review will focus on currently available non-invasive markers of cirrhosis. The evidence behind the use of these markers will be highlighted, along with an assessment of diagnostic accuracy and performance characteristics of each test. Non-invasive markers of cirrhosis can be radiologic or serum-based. Radiologic techniques based on ultrasound, magnetic resonance imaging and elastography have been used to assess liver fibrosis. Serum-based biomarkers of cirrhosis have also been developed. These are broadly classified into indirect and direct markers. Indirect biomarkers reflect liver function, which may decline with the onset of cirrhosis. Direct biomarkers, reflect extracellular matrix turnover, and include molecules involved in hepatic fibrogenesis. On the whole, radiologic and serum markers of fibrosis correlate well with biopsy scores, especially when excluding cirrhosis or excluding fibrosis. This feature is certainly clinically useful, and avoids liver biopsy in many cases.

Biomarkers in nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a chronic liver condition characterized by insulin resistance, type 2 diabetes and fat accumulation in the liver that may cause hepatic inflammation and progressive scarring leading to nonalcoholic steatohepatitis (NASH) and irreversible liver damage (cirrhosis). As a result, there has been increased recognition of the need to assess and closely monitor individuals for risk factors of components of NAFLD and NASH, as well as the severity of these conditions using biomarkers.

AIM

To review the biomarkers used to diagnose and define the severity of NAFLD and NASH.

METHODS

A comprehensive PubMed and Google Scholar literature search was performed using the terms "non-alcoholic fatty liver disease", "non-alcoholic steatohepatitis", as well as the name of each biomarker known to be used. Articles indexed between 2004 and 2014 were used. Each author read the publications separately and the results were discussed.

RESULTS

Biomarkers offer a potential prognostic or diagnostic indicator for disease manifestation, progression or both. Serum biomarkers, including total cholesterol, triglycerides, insulin resistance and C-peptide, have been used for many years. Emerging biomarkers, such as apolipoprotein A1, apolipoprotein B, leptin, adiponectin, free fatty acids, ghrelin and tumour necrosis factor-alpha, have been proposed as tools that could provide valuable complementary information to that obtained from traditional biomarkers. Moreover, markers of cell death and mitochondrial dysfunction (cytokeratins) represent powerful predictors of risk. For biomarkers to be clinically useful in accurately diagnosing and treating disorders, age-specific reference intervals that account for differences in sex and ethnic origin are a necessity.

CONCLUSIONS

The present review attempts to provide a comprehensive analysis of the emerging risk biomarkers of NAFLD and NASH, and to use the clinical significance and analytical considerations of each biomarker pointing out sentinel features of disease progression.

The clinical significance of serum ferritin in pediatric non-alcoholic Fatty liver disease

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) in children has become an important public health issue because of its high prevalence and severity. Several noninvasive methods for estimating NAFLD are under investigation. We aimed to evaluate the usefulness of serum ferritin as a biomarker of severity of pediatric NAFLD patients.

METHODS

A total of 64 NAFLD patient were enrolled from Severance Children's Hospital from March 2010 to February 2013. Serum ferritin levels, liver related laboratory tests, liver magnetic resonance imaging (MRI) (2-dimensional [2D] proton density-fat fraction) and NAFLD severity markers were compared between obese group and overweight group. Correlation analyses were performed between serum ferritin and laboratory values including NAFLD severity markers.

RESULTS

In obese group, serum ferritin, alanine aminotransferase (ALT), total bilirubin, international normalized ratio (INR), MRI 2D proton density-fat fraction, aspartate aminotransferase (AST) to platelet ratio index (APRI) and fibrosis-4 (FIB-4) (an index score calculated from platelet count, ALT, AST and age) were significantly higher than those of overweight group. NAFLD severity markers, APRI and FIB-4, and liver specific important laboratory values, AST, ALT, INR, cholesterol, triglyceride and low density lipoprotein show significant correlation with serum ferritin in NAFLD patients.

CONCLUSION

Serum ferritin concentrations could be a candidate of useful severity marker in the pediatric NAFLD patients.

Magnetic resonance elastography predicts advanced fibrosis in patients with nonalcoholic fatty liver disease: a prospective study

Retrospective studies have shown that two-dimensional magnetic resonance elastography (2D-MRE), a novel MR method for assessment of liver stiffness, correlates with advanced fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). Prospective data on diagnostic accuracy of 2D-MRE in the detection of advanced fibrosis in NAFLD are needed. The aim of this study is to prospectively assess the diagnostic accuracy of 2D-MRE, a noninvasive imaging biomarker, in predicting advanced fibrosis (stage 3 or 4) in well-characterized patients with biopsy-proven NAFLD. This is a cross-sectional analysis of a prospective study including 117 consecutive patients (56% women) with biopsy-proven NAFLD who underwent a standardized research visit: history, exam, liver biopsy assessment (using the nonalcoholic steatohepatitis Clinical Research Network histological scoring system), and 2D-MRE from 2011 to 2013. The radiologist and pathologist were blinded to clinical and pathology/imaging data, respectively. Receiver operating characteristics (ROCs) were examined to assess the diagnostic test performance of 2D-MRE in predicting advanced fibrosis. The mean (± standard deviation) of age and body mass index was 50.1 (± 13.4) years and 32.4 (± 5.0) kg/m(2), respectively. The median time interval between biopsy and 2D-MRE was 45 days (interquartile range: 50 days). The number of patients with fibrosis stages 0, 1, 2, 3, and 4 was 43, 39, 13, 12, and 10, respectively. The area under the ROC curve for 2D-MRE discriminating advanced fibrosis (stage 3-4) from stage 0-2 fibrosis was 0.924 (P < 0.0001). A threshold of >3.63 kPa had a sensitivity of 0.86 (95% confidence interval [CI]: 0.65-0.97), specificity of 0.91 (95% CI: 0.83-0.96), positive predictive value of 0.68 (95% CI: 0.48-0.84), and negative predictive value of 0.97 (95% CI: 0.91-0.99).

CONCLUSIONS

MRE is accurate in predicting advanced fibrosis and may be utilized for noninvasive diagnosis of advanced fibrosis in patients with NAFLD.

Noninvasive Biomarkers of Liver Fibrosis: Clinical Applications and Future Directions

Chronic liver disease is a significant cause of morbidity and mortality worldwide. Current strategies for assessing prognosis and treatment rely on accurate assessment of disease stage. Liver biopsy is the gold standard for assessing fibrosis stage but has many limitations. Noninvasive biomarkers of liver fibrosis have been extensively designed, studied, and validated in a variety of liver diseases. With the advent of direct acting antivirals and the rise in obesity-related liver disease, there is a growing need to establish these noninvasive methods in the clinic. In addition, it has become increasingly clear over the last few years that noninvasive biomarkers can also be used to monitor response to antifibrotic therapies and predict liver outcomes, including hepatocellular carcinoma development. This review highlights the most well-established noninvasive biomarkers to-date, with a particular emphasis on serum and imaging-based methodologies.

Non-alcoholic fatty liver disease in patients with diabetes mellitus

Non-alcoholic fatty liver disease (NAFLD), including the disease stages steatosis and non-alcoholic steatohepatitis, is the most common cause of chronic liver disease worldwide and linked to the epidemic of diabetes mellitus and obesity. It is characterized by a high cardiovascular and liver-related mortality and expected to be the leading cause for liver transplantation in the near future. This review summarizes recent progress made in our understanding of the disease pathogenesis and the clinical management of patients with NAFLD. Strategies to manage diabetes mellitus will be evaluated in terms of their effectiveness in treating patients with NAFLD and novel pharmacological targets capable to treat diabetes mellitus and NAFLD will be highlighted.

Noninvasive biomarkers in non-alcoholic fatty liver disease: Current status and a glimpse of the future

The development of non invasive biomarkers of disease has become a major focus of interest in nonalcoholic fatty liver disease (NAFLD). The large prevalence of the disease and the invasive nature of the investigation means that screening with liver biopsy is impractical. In addition to screening, the differentiation of those with simple steatosis vs steatohepatitis and fibrosis is clinically important as the prognosis of each differs. Serum biomarkers may be a combination of simple markers derived from large data sets or direct markers of disease activity. Serum markers of inflammation, apoptosis and oxidative stress in addition to fibrosis have been extensively studied in patients with NAFLD. Other techniques such as transient elastography, magnetic resonance elastography and acoustic radiation force imaging are becoming more established as noninvasive methods of detecting fibrosis in a variety of chronic liver conditions in addition to NAFLD. Newer high throughput methods such as proteomics and glycomics allow the nonhypothesis-driven identification of novel markers and may also potentially contribute to our understanding of the pathogenesis of the condition. This review addresses some of the methodological issues which need to be considered in the search for the ideal biomarker. It is likely that a combination of serum biomarkers and techniques such as transient elastography may provide the optimal diagnostic discrimination however this remains to be proven in large studies.

Non-alcoholic fatty liver disease and diabetes: From physiopathological interplay to diagnosis and treatment

Non-alcoholic fatty liver disease (NAFLD) is highly prevalent in patients with diabetes mellitus and increasing evidence suggests that patients with type 2 diabetes are at a particularly high risk for developing the progressive forms of NAFLD, non-alcoholic steatohepatitis and associated advanced liver fibrosis. Moreover, diabetes is an independent risk factor for NAFLD progression, and for hepatocellular carcinoma development and liver-related mortality in prospective studies. Notwithstanding, patients with NAFLD have an elevated prevalence of prediabetes. Recent studies have shown that NAFLD presence predicts the development of type 2 diabetes. Diabetes and NAFLD have mutual pathogenetic mechanisms and it is possible that genetic and environmental factors interact with metabolic derangements to accelerate NAFLD progression in diabetic patients. The diagnosis of the more advanced stages of NAFLD in diabetic patients shares the same challenges as in non-diabetic patients and it includes imaging and serological methods, although histopathological evaluation is still considered the gold standard diagnostic method. An effective established treatment is not yet available for patients with steatohepatitis and fibrosis and randomized clinical trials including only diabetic patients are lacking. We sought to outline the published data including epidemiology, pathogenesis, diagnosis and treatment of NAFLD in diabetic patients, in order to better understand the interplay between these two prevalent diseases and identify the gaps that still need to be fulfilled in the management of NAFLD in patients with diabetes mellitus.

Clinical differences between alcoholic liver disease and nonalcoholic fatty liver disease

Alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD) are serious health problems worldwide. These two diseases have similar pathological spectra, ranging from simple hepatic steatosis to steatohepatitis, liver cirrhosis, and hepatocellular carcinoma. Although most subjects with excessive alcohol or food intake experience simple hepatic steatosis, a small percentage of individuals will develop progressive liver disease. Notably, both ALD and NAFLD are frequently accompanied by extrahepatic complications, including cardiovascular disease and malignancy. The survival of patients with ALD and NAFLD depends on various disease-associated conditions. This review delineates the clinical characteristics and outcomes of patients with ALD and NAFLD by comparing their epidemiology, the factors associated with disease susceptibility and progression, and the predictors and characteristics of outcomes. A comprehensive understanding of the characteristics and outcomes of ALD and NAFLD is imperative in the management of these chronic liver diseases.

Serum ferritin levels lack diagnostic accuracy for liver fibrosis in patients with nonalcoholic fatty liver disease

BACKGROUND & AIMS

Series studies have associated increased serum levels of ferritin with liver fibrosis in patients with nonalcoholic fatty liver disease. We aimed to determine the accuracy with which measurements of serum ferritin determine the presence and severity of liver fibrosis, and whether combining noninvasive scoring systems with serum ferritin analysis increases the accuracy of diagnosis of advanced liver fibrosis.

METHODS

We performed a retrospective analysis of data from 1014 patients with liver biopsy-confirmed nonalcoholic fatty liver disease. Three cut points of serum ferritin level, adjusted for sex, were established based on receiver operating characteristic curve analysis: 1.0-, 1.5-, and 2.0-fold the upper limit of normal. Three multiple logistic regression models were created to determine the association of these cutoff values with liver fibrosis, adjusting for age, sex, race, diabetes, body mass index, and level of alanine aminotransferase.

RESULTS

A greater proportion of patients with increased serum levels of ferritin had definitive nonalcoholic steatohepatitis and more-advanced fibrosis than patients without increased levels. In all models, serum level of ferritin was significantly associated with the presence and severity of liver fibrosis. However, for all 3 cutoff values, area under the receiver operating characteristic curve values were low (less than 0.60) for the presence of fibrosis or any stage of liver fibrosis; ferritin level identified patients with fibrosis with 16%-41% sensitivity and 70%-92% specificity. The accuracy with which noninvasive scoring systems identified patients with advanced fibrosis did not change with inclusion of serum ferritin values.

CONCLUSIONS

Although serum levels of ferritin correlate with more-severe liver fibrosis, based on adjusted multiple logistic regression analysis, serum ferritin levels alone have a low level of diagnostic accuracy for the presence or severity of liver fibrosis in patients with nonalcoholic fatty liver disease.

Non-alcoholic fatty liver disease: a practical approach to diagnosis and staging

Non-alcoholic fatty liver disease (NAFLD) is now the commonest cause of abnormal liver function tests (LFTs) in the UK with approximately a third of the population being affected. The exact prevalence is not known, but population studies from the USA and China using magnetic resonance spectroscopy estimate that approximately 30% of the general population have steatosis. It is a spectrum of disease ranging from simple steatosis, to non-alcoholic steatohepatitis (NASH), through to advanced fibrosis and cirrhosis. The majority have simple steatosis, but approximately 10-30% develop NASH and the development of NASH cirrhosis is associated with a poor long-term prognosis. Patients with NASH have increased liver-related and cardiovascular mortality. Many patients with NAFLD remain undiagnosed, and recognising those at risk is the first step. Clinicians overly rely on abnormal liver enzymes to identify patients with NAFLD, so patients with significant liver disease can be overlooked, potentially missing opportunities for intervention. Although liver biopsy is the gold standard method for diagnosing and staging NAFLD, the majority of patients can be effectively diagnosed non-invasively with tests that are routinely available in the clinic today. This review discusses a pragmatic approach to diagnosis and staging of NAFLD so that patients at the highest risk of liver-related complications can be identified.

Nonalcoholic fatty liver disease: Updates in noninvasive diagnosis and correlation with cardiovascular disease

Nonalcoholic fatty liver disease (NAFLD) refers to the accumulation of fat (mainly triglycerides) within hepatocytes. Approximately 20%-30% of adults in the general population in developed countries have NAFLD; this trend is increasing because of the pandemicity of obesity and diabetes, and is becoming a serious public health burden. Twenty percent of individuals with NAFLD develop chronic hepatic inflammation [nonalcoholic steatohepatitis (NASH)], which can be associated with the development of cirrhosis, portal hypertension, and hepatocellular carcinoma in a minority of patients. And thus, the detection and diagnosis of NAFLD is important for general practitioners. Liver biopsy is the gold standard for diagnosing NAFLD and confirming the presence of NASH. However, the invasiveness of this procedure limits its application to screening the general population or patients with contraindications for liver biopsy. The development of noninvasive diagnostic methods for NAFLD is of paramount importance. This review focuses on the updates of noninvasive diagnosis of NAFLD. Besides, we review clinical evidence supporting a strong association between NAFLD and the risk of cardiovascular disease because of the cross link between these two disorders.

Biomarkers of liver fibrosis

Liver fibrosis is the final common pathway for almost all causes of chronic liver injury. Liver fibrosis is now known to be a dynamic process having significant potential for resolution. Therefore, fibrosis prediction is an essential part of the assessment and management of patients with chronic liver disease. As such, there is strong demand for reliable liver biomarkers that provide insight into disease etiology, diagnosis, therapy, and prognosis in lieu of more invasive approaches such as liver biopsy. Current diagnostic strategies range from use of serum biomarkers to more advanced imaging techniques including transient elastography and magnetic resonance imaging. In addition to these modalities, there are other approaches including the use of novel, but yet to be validated, biomarkers. In this chapter, we discuss the biomarkers of liver fibrosis including the use of invasive and noninvasive biomarkers and disease-specific biomarkers in various chronic liver diseases.

Surgery in patients with portal hypertension: a preoperative checklist and strategies for attenuating risk

Patients with liver disease and portal hypertension are at increased risk of complications from surgery. Recent advances have allowed better optimization of patients with cirrhosis before surgery and a reduction in postoperative complications. Despite this progress, the estimation of surgical risk in a patient with cirrhosis is challenging. The MELD score has shown promise in predicting postoperative mortality compared with the Child-Turcotte-Pugh score. This article addresses current concepts in the perioperative evaluation of patients with liver disease and portal tension, including a preoperative liver assessment (POLA) checklist that may be useful towards mitigating perioperative complications.

Serum immunoglobulin levels predict fibrosis in patients with non-alcoholic fatty liver disease

BACKGROUND & AIMS

A third of the population are estimated to have NAFLD of varying severity. Serum immunoglobulins are frequently elevated in patients with chronic liver disease, but little is known about serum immunoglobulin levels in patients with NAFLD. Aim of this study was to evaluate serum immunoglobulin levels (IgA, IgG, and IgM) in a large cohort of patients with biopsy-proven NAFLD and determine if immunoglobulin levels are associated with clinical or histological features.

METHODS

Patients seen in a tertiary fatty liver clinic between 1999 and 2009 were included. Liver biopsies were assessed using the Kleiner score. Immunoglobulin levels and other blood tests were taken at time of biopsy.

RESULTS

285 patients (110 simple steatosis and 175 NASH) had serum immunoglobulins measured within 6months of liver biopsy. 130 (46%) patients had elevated (>1× upper limit of normal) serum IgA levels, 28 (10%) patients had elevated IgG and 22 (8%) raised IgM. Serum IgA levels were elevated more frequently in patients with NASH compared with subjects with simple steatosis (55% vs. 31%, p<0.001). Overall, 55 (19%) patients had advanced liver fibrosis (Kleiner stage 3-4). There was a significant positive association between serum IgA levels and the stage of fibrosis (p<0.001). Serum IgA, age, platelets, AST/ALT ratio and BMI were all independently with advanced fibrosis following multivariate analysis. A model constructed from these independent predictors accurately predicted advanced fibrosis (AUROC 0.87).

CONCLUSIONS

The serum IgA level was frequently elevated in patients with NAFLD and was an independent predictor of advanced fibrosis.

Noninvasive Diagnosis of NASH and Liver Fibrosis Within the Spectrum of NAFLD

Nonalcoholic fatty liver disease (NAFLD) is the most common type of chronic liver disease in the United States, affecting an estimated 70 million Americans. The histologic spectrum of NAFLD ranges from simple steatosis to nonalcoholic steatohepatitis (NASH), fibrosis, and eventually cirrhosis. Patients with NASH and significant fibrosis seen on liver biopsy have an increased risk for liver-related morbidity and mortality compared to patients with simple steatosis. Due to the high prevalence of NAFLD, there has been an urgent need to develop reliable noninvasive markers and tests that can accurately predict the presence of advanced disease without the need for liver biopsy. These tests can be divided into 2 groups: those that predict the presence of NASH (such as markers of hepatocyte apoptosis, oxidative stress, and inflammation, as well as predictive models based on clinical variables) and those that predict the presence of fibrosis (such as simple and complex predictive models). This paper provides an overview of various noninvasive methods for detecting NAFLD and suggests a diagnostic algorithm that can be used in clinical practice.

M30 does not predict the severity of hepatosteatosis, whereas adiponectin level declined with increase of ALT and the severity of hepatic steatosis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is an emerging problem all over the world. Because NAFLD and polycystic ovary syndrome (PCOS) are both closely related with insulin resistance, it would be necessary to determine the rate of presence of NAFLD in PCOS patients. So, this study aimed to investigate the utility of M30 in PCOS patients for the diagnosis of hepatic injury.

METHODS

Eighty patients with PCOS were included in the study. Ultrasonographic examination for the presence of hepatic steatosis, M30 serum level for determining the severity of ongoing apoptotic cell death in liver, and BARD index for defining the hepatic injury were performed during the study. 25-OH vitamin D and adiponectin level in sera were studied using ELISA (Enzyme-Linked ImmunoSorbent Assay).

RESULTS

M30 and vitamin D levels did not change significantly with the severity of hepatic steatosis. On the other hand, M30 levels showed a positive correlation with ALT and AST levels, and M30 level suddenly increased with the presence of hepatic steatosis from 159.7 to 170 U/l, however stabilized with the increasing severity of hepatic setatosis. Adiponectin levels decreased with the increasing severity of hepatic steatosis and significantly varied between ALT greater than 40 U/l and less than 40 U/l.

CONCLUSIONS

M30 level in serum increased with the appearance of hepatic steatosis and had a positive correlation with a noninvasive hepatic injury test, BARD (BMI, aspartate aminotransferase [AST]/alanine aminotransferase [ALT] ratio [AAR], diabetes mellitus [DM]) index. Adiponectin level decreased with the increasing ALT level and severity of hepatic steatosis.

Systematic review with meta-analysis: non-invasive assessment of non-alcoholic fatty liver disease--the role of transient elastography and plasma cytokeratin-18 fragments

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) affects 15-40% of the general population. Some patients have non-alcoholic steatohepatitis (NASH) and progressive fibrosis, and would be candidates for monitoring and treatment.

AIM

To review current literature on the use of non-invasive tests to assess the severity of NAFLD.

METHODS

Systematic literature searching identified studies evaluating non-invasive tests of NASH and fibrosis using liver biopsy as the reference standard. Meta-analysis was performed for areas with adequate number of publications.

RESULTS

Serum tests and physical measurements like transient elastography (TE) have high negative predictive value (NPV) in excluding advanced fibrosis in NAFLD patients. The NAFLD fibrosis score comprises of six routine clinical parameters and has been endorsed by current American guidelines as a screening test to exclude low-risk individuals. The pooled sensitivities and specificities for TE to diagnose F ≥ 2, F ≥ 3 and F4 disease were 79% and 75%, 85% and 85%, and 92% and 92% respectively. Liver stiffness measurement often fails in obese patients, but the success rate can be improved with the use of the XL probe. A number of biomarkers have been developed for the diagnosis of NASH, but few were independently validated. Serum/plasma cytokeratin-18 fragments have been most extensively evaluated and have a pooled sensitivity of 66% and specificity of 82% in diagnosing NASH.

CONCLUSIONS

Current non-invasive tests are accurate in excluding advanced fibrosis in NAFLD patients, and may be used for initial assessment. Further development and evaluation of NASH biomarkers are needed.

Review article: The prevention and reversal of hepatic fibrosis in autoimmune hepatitis

BACKGROUND

Immunosuppressive treatment of autoimmune hepatitis can prevent or reverse hepatic fibrosis, but these anti-fibrotic effects are inconsistent secondary gains.

AIM

To describe the anti-fibrotic effects of current therapies for autoimmune hepatitis, discuss the pathogenic mechanisms of hepatic fibrosis that might be targeted by anti-fibrotic interventions, indicate the non-invasive diagnostic tests of hepatic fibrosis that must be validated in autoimmune hepatitis and to suggest promising treatment opportunities.

METHODS

Studies cited in PubMed from 1972 to 2013 for autoimmune hepatitis, hepatic fibrosis, cirrhosis, anti-fibrotic therapy and non-invasive tests of hepatic fibrosis were selected.

RESULTS

Hepatic fibrosis improves in 53-57% of corticosteroid-treated patients with autoimmune hepatitis; progressive fibrosis slows or is prevented in 79%; and cirrhosis may be reversed. Progressive hepatic fibrosis is associated with liver inflammation, and the inability to fully suppress inflammatory activity within 12 months is associated with progression to cirrhosis (54%) and death or need for liver transplantation (15%). Liver tissue examination remains the gold standard for assessing hepatic fibrosis, but laboratory and radiological tests may be useful non-invasive methods to measure the fibrotic response. Severe liver inflammation can confound radiological assessments, and the preferred non-invasive test in autoimmune hepatitis is uncertain. Individualised treatment adjustments and adjunctive anti-fibrotic therapies are poised for study in this disease.

CONCLUSIONS

The prevention and reversal of hepatic fibrosis are achievable objectives in autoimmune hepatitis. Strategies that evaluate individualised therapies adjusted to the rapidity and completeness of the inflammatory response, and the use of adjunctive anti-fibrotic interventions, must be evaluated.

The interactions of nonalcoholic fatty liver disease and cardiovascular diseases

A complex interaction among metabolic factors, adipose tissue lipolysis, oxidative stress, and insulin resistance results in a deleterious process that may link nonalcoholic fatty liver disease (NAFLD) with severe cardiovascular (CV) outcomes. Patients with NAFLD are at higher risk of atherosclerosis, new onset of CV events, and overall mortality. The strong association between NAFLD and CV disease should affect clinical practice, with screening and surveillance of patients with NAFLD. This review discusses the data linking these major diseases.

Limitations of liver biopsy and non-invasive diagnostic tests for the diagnosis of nonalcoholic fatty liver disease/nonalcoholic steatohepatitis

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.

Cohort study of non-alcoholic fatty liver disease, NAFLD fibrosis score, and the risk of incident diabetes in a Korean population

OBJECTIVES

No study has evaluated an association between non-alcoholic fatty liver disease (NAFLD) severity and the incidence of diabetes. We examined whether NAFLD and its severity-using the NAFLD fibrosis score (NFS)-predict the development of diabetes.

METHODS

A cross-sectional study was performed in 43,166 apparently healthy Koreans aged 30-59 years, who underwent a health checkup in 2005 and 2006. Of these, 38,291 subjects without diabetes were followed annually or biennially until December 2011 for the cohort study. NAFLD was defined as hepatic steatosis on ultrasonography in the absence of excessive alcohol use or other identifiable causes. The NFS was used to categorize the severity of fibrosis. Diabetes was defined as fasting serum glucose ≥126 mg/dl, glycated hemoglobin (HbA1c) ≥6.5%, or medication use for diabetes.

RESULTS

During 175,996 person-years of follow-up, 2,025 participants developed diabetes. An increase across NAFLD categories was positively associated with an increased risk of diabetes in both the cross-sectional and cohort studies in a dose-response manner (P-trend <0.001). In multivariate-adjusted models, the hazard ratios (95% confidence intervals) for diabetes comparing NAFLD with low NFS and NAFLD with intermediate or high NFS vs. no NAFLD were 2.00 (1.79-2.24) and 4.74 (3.67-6.13), respectively. This association remained significant even in subjects with fasting glucose <100 mg/dl and subjects with HbA1c <5.8%.

CONCLUSIONS

In this cohort study of a healthy Korean population, NAFLD and its severity using NFS were independently and strongly associated with increased incidence of diabetes in men and women-even with a euglycemic range of glucose and HbA1c.

Paediatric gastroenterology evaluation of overweight and obese children referred from primary care for suspected non-alcoholic fatty liver disease

BACKGROUND

Screening overweight and obese children for non-alcoholic fatty liver disease (NAFLD) is recommended by paediatric and endocrinology societies. However, gastroenterology societies have called for more data before making a formal recommendation.

AIM

To determine whether the detection of suspected NAFLD in overweight and obese children through screening in primary care and referral to paediatric gastroenterology resulted in a correct diagnosis of NAFLD.

METHODS

Information generated in the clinical evaluation of 347 children identified with suspected NAFLD through screening in primary care and referral to paediatric gastroenterology was captured prospectively. Diagnostic outcomes were reported. The diagnostic performance of two times the upper limit of normal (ULN) for alanine aminotransferase (ALT) was assessed.

RESULTS

Non-alcoholic fatty liver disease was diagnosed in 55% of children identified by screening and referral. Liver disease other than NAFLD was present in 18% of those referred. Autoimmune hepatitis was the most common alternative diagnosis. Children with NAFLD had significantly (P < 0.05) higher screening ALT (98 ± 95) than children with liver disease other than NAFLD (86 ± 74). Advanced fibrosis was present in 11% of children. For the diagnosis of NAFLD, screening ALT two times the clinical ULN had a sensitivity of 57% and a specificity of 71%.

CONCLUSIONS

Screening of overweight and obese children in primary care for NAFLD with referral to paediatric gastroenterology has the potential to identify clinically relevant liver pathology. Consensus is needed on how to value the risk and rewards of screening and referral, to identify children with liver disease in the most appropriate manner.

Noninvasive evaluation of NAFLD

A common clinical concern in patients with NAFLD is whether they have NASH or simple steatosis and, more importantly, what the stage of fibrosis is and whether the level of fibrosis has increased over time. Such concern is based on the fact that patients with NAFLD with advanced fibrosis are at greatest risk of developing complications of end-stage liver disease. Although it lacks sensitivity, ultrasonography is an accepted tool for steatosis screening. The controlled attenuation parameter or CAP seems a promising screening technique, but requires further validation. Cytokeratin-18 has been extensively validated, but it is an imperfect serum marker of NASH. Ultrasonography-based transient elastography can exclude advanced fibrosis and cirrhosis, but its main limitation is its reduced applicability in patients with NAFLD, which is not completely solved by use of the XL probe. Of the noninvasive serum markers, the NAFLD fibrosis score is the most validated and has appropriate accuracy in distinguishing patients with and without advanced fibrosis. Although noninvasive methods require further validation, they could be useful for selecting those patients with NAFLD who require a liver biopsy. This Review discusses the advantages and limitations of noninvasive methods for the management of adults with NAFLD, including diagnosis and quantification of steatosis, diagnosis of NASH and staging of hepatic fibrosis.

Laboratory-based scoring system for prediction of hepatic inflammatory activity in patients with autoimmune hepatitis

BACKGROUND & AIMS

In autoimmune hepatitis (AIH), inflammation is closely related to fibrosis. Although transaminase levels are commonly used to assess hepatic inflammation, they may not relate directly to the histology. We developed a noninvasive diagnostic score as an alternative to liver biopsy to help optimize treatment for AIH and monitor disease progress.

METHODS

Eighty-two participants with type 1 AIH who had undergone liver biopsy were included (44 in training and 38 in validation sets). Liver histology was assessed according to the histologic activity index (HAI; score 0-18) and Ishak's histologic fibrosis index (HFI; score 0-6). High inflammation was defined as HAI>4, and advanced fibrosis was defined as HFI>2. Routine laboratory test findings and stepwise linear regression were used to develop the best models predicting HAI and HFI. The best cut-off value to predict high inflammation and advanced fibrosis for these formulas was then calculated based on receiver-operating characteristic analysis.

RESULTS

The cut-off value for a model predicting high inflammation was ≥3.57 (AUROC = 0.93; 95% CI: 0.86-1.00), with 100% sensitivity and 85% specificity. High inflammation was confirmed with an 81% positive predictive value and excluded with a 100% negative predictive value. In the validation set, the sensitivity, specificity, positive predictive value and negative predictive values were 100, 56, 88 and 100% respectively. The diagnostic yield of the fibrosis score was unsatisfactory.

CONCLUSIONS

The noninvasive inflammatory score based on four routine laboratory parameters discriminated patients with and without significant hepatic inflammation and may facilitate follow-up of type 1 AIH patients.

Simple noninvasive systems predict long-term outcomes of patients with nonalcoholic fatty liver disease

BACKGROUND & AIMS

Some patients with nonalcoholic fatty liver disease (NAFLD) develop liver-related complications and have higher mortality than other patients with NAFLD. We determined the accuracy of simple, noninvasive scoring systems in identification of patients at increased risk for liver-related complications or death.

METHODS

We performed a retrospective, international, multicenter cohort study of 320 patients diagnosed with NAFLD, based on liver biopsy analysis through 2002 and followed through 2011. Patients were assigned to mild-, intermediate-, or high-risk groups based on cutoff values for 2 of the following: NAFLD fibrosis score, aspartate aminotransferase/platelet ratio index, FIB-4 score, and BARD score. Outcomes included liver-related complications and death or liver transplantation. We used multivariate Cox proportional hazard regression analysis to adjust for relevant variables and calculate adjusted hazard ratios (aHRs).

RESULTS

During a median follow-up period of 104.8 months (range, 3-317 months), 14% of patients developed liver-related events and 13% died or underwent liver transplantation. The aHRs for liver-related events in the intermediate-risk and high-risk groups, compared with the low-risk group, were 7.7 (95% confidence interval [CI]: 1.4-42.7) and 34.2 (95% CI: 6.5-180.1), respectively, based on NAFLD fibrosis score; 8.8 (95% CI: 1.1-67.3) and 20.9 (95% CI: 2.6-165.3) based on the aspartate aminotransferase/platelet ratio index; and 6.2 (95% CI: 1.4-27.2) and 6.6 (95% CI: 1.4-31.1) based on the BARD score. The aHRs for death or liver transplantation in the intermediate-risk and high-risk groups compared with the low-risk group were 4.2 (95% CI: 1.3-13.8) and 9.8 (95% CI: 2.7-35.3), respectively, based on the NAFLD fibrosis scores. Based on aspartate aminotransferase/platelet ratio index and FIB-4 score, only the high-risk group had a greater risk of death or liver transplantation (aHR = 3.1; 95% CI: 1.1-8.4 and aHR = 6.6; 95% CI: 2.3-20.4, respectively).

CONCLUSIONS

Simple noninvasive scoring systems help identify patients with NAFLD who are at increased risk for liver-related complications or death. NAFLD fibrosis score appears to be the best indicator of patients at risk, based on HRs. The results of this study require external validation.

APRI, the FIB-4 score, and Forn's index have noninvasive diagnostic value for liver fibrosis in patients with chronic hepatitis B

OBJECTIVES

The aim of this study was to evaluate the potential use of serum transforming growth factor-β1 (TGF-β1), tissue inhibitor of metalloproteinase-1 (TIMP-1), fetuin-A, and fibroblast growth factor 21 (FGF21) in the detection of liver fibrosis in patients with chronic hepatitis B (CHB). The value of the noninvasive fibrosis models - that is, the aspartate aminotransferase to platelet ratio index (APRI), the fibrosis index based on the four factors (FIB-4) score, and Forn's index - was also examined.

MATERIALS AND METHODS

CHB patients who underwent liver biopsy for the evaluation of fibrosis were included in the study. A total of 73 patients were divided into two groups according to their METAVIR scores (F0-1, no/minimal fibrosis; F2-4, significant fibrosis). Serum levels of TGF-β1, TIMP-1, fetuin-A, and FGF21 were measured besides APRI, FIB-4, and Forn's scores. The area under the receiver operating characteristic curve was measured for each parameter, followed by calculation of sensitivity, specificity, and positive and negative predictive values.

RESULTS

APRI, FIB-4, and Forn's index scores were significantly higher in patients with significant fibrosis (P<0.05). There was no difference between no/minimal fibrosis and significant fibrosis groups in terms of serum levels of TGFβ-1, TIMP-1, fetuin-A, and FGF21 (P>0.05). The areas under the receiver operating characteristic curve for TGF-β1, TIMP-1, fetuin-A, FGF21, APRI, FIB-4, and Forn's index were 0.445, 0.483, 0.436, 0.585, 0.662, 0.687, and 0.680, respectively.

CONCLUSION

Our results suggest that serum TGF-β1, TIMP-1, fetuin-A, and FGF21 are not useful for the assessment of the extent of liver fibrosis in CHB in this patient group. However, APRI, FIB-4, and Forn's index have a better diagnostic value in patients with significant fibrosis than in those with no/minimal fibrosis.

Noninvasive scoring systems in patients with nonalcoholic fatty liver disease with normal alanine aminotransferase levels

BACKGROUND

The severity of liver fibrosis must be estimated to determine the prognosis, for surveillance, and for optimal treatment of nonalcoholic fatty liver disease (NAFLD). However, the severity of hepatic fibrosis tends to be underestimated in patients with normal ALT.

METHODS

We investigated histological data and scoring systems (FIB-4 index, NAFLD fibrosis score, BARD score, and AST/ALT ratio) of 1,102 liver-biopsy-confirmed NAFLD patients.

RESULTS

A total of 235 NAFLD patients with normal ALT were estimated to exist. The ratio of advanced fibrosis (stage 3-4) was seen in 16.1 % of subjects with normal ALT. Scoring systems, especially the FIB-4 index and NAFLD fibrosis score, were clinically very useful (AUROC >0.8), even in patients with normal ALT. Furthermore, with resetting of the cutoff values, the FIB-4 index (>1.659) and NAFLD fibrosis score (>0.735) were found to have a higher sensitivity and higher specificity for the prediction of advanced fibrosis, and all of these scoring systems (FIB-4 index, NAFLD fibrosis score, BARD score, and AST/ALT ratio) had higher negative predictive values (>90.3 %). By using the resetting cutoff value, liver biopsy could have been avoided in 60.4 % (FIB-4), 66.4 % (NAFLD fibrosis score), 51.9 % (BARD score), and 62.1 % (AST/ALT ratio).

CONCLUSIONS

We reset the cutoff values of numerous non-invasive scoring systems to improve their clinical usefulness in the prediction of liver fibrosis in NAFLD patients with normal ALT, and these non-invasive scoring systems with the reset cutoff values could be of substantial benefit to reduce the number of liver biopsies performed.