Spectrum of NAFLD and diagnostic implications of the proposed new normal range for serum ALT in obese women

Non-invasive diagnosis and staging of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is considered to be the hepatic manifestation of the metabolic syndrome and is characterized by ectopic accumulation of triglycerides in the cytoplasm of hepatocytes, i.e., steatosis. NAFLD has become the most common chronic liver disease, with an estimated global prevalence of 25%. Although the majority of NAFLD patients will never experience liver-related complications, the progressive potential of NAFLD is indisputable, with 5-10% of subjects progressing to cirrhosis, end-stage liver disease, or hepatocellular carcinoma. NAFLD patients with advanced fibrosis are at the highest risk of developing cardiovascular and cirrhosis-related complications. Liver biopsy has hitherto been considered the reference method for evaluation of hepatic steatosis and fibrosis stage. Given the limitations of biopsy for widescale screening, non-invasive tests (NITs) for assessment of steatosis and fibrosis stage, including serum-based algorithms and ultrasound- and magnetic resonance-based methods, will play an increasing role in the management of NAFLD patients. This comprehensive review presents the advantages and limitations of NITs for identification of steatosis and advanced fibrosis in NAFLD. The clinical implications of using NITs to identify and manage NAFLD patients are also discussed.

[Elevated liver function tests - as incidental finding in general practice]

Elevated liver function tests - as incidental finding in general practice Abstract. In general practice, elevated liver function tests are found in 25 % of patients presenting with unspecific symptoms or during a routine health checkup. Approximately 2.5 % of the general population are expected to show elevated values. Conversely, liver disease can present without abnormal liver function tests. Liver disease is not only frequent but may also imply a significant mortality. Worldwide its prevalence is steadily rising, and liver disease has become the fifth leading cause of death. Responsible for the rapidly increasing prevalence are primarily non-alcoholic fatty liver disease (NAFLD), alcohol-related liver disease (ARLD) and viral hepatitis. Due to the large range of possible differential diagnoses and the coexistence of aetiologies liver diseases represent a diagnostic challenge with important prognostic implication. In case of elevated liver function, a detailed medical history and a thorough clinical examination should be performed first. This allows narrowing down possible causes to the few most likely differential diagnoses. Subsequently, depending on the level of elevated liver function and the clinical presentation as hepatitis or cholestasis, screening tests for differential liver diseases are performed. Laboratory diagnostics and obligatory ultrasound scan can be supplemented by non-invasive methods (e. g. elastography, MRI / MRCP / CT) and in selected cases invasive methods (liver biopsy, ERCP). In the following article we delineate the diagnostic approach to elevated liver function tests using algorithms.

Noninvasive Evaluation of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver diseases and can progress to advanced fibrosis and end-stage liver disease. Thus, intensive research has been performed to develop noninvasive methods for the diagnosis of nonalcoholic steatohepatitis (NASH) and fibrosis. Currently, no single noninvasive tool covers all of the stages of pathologies and conditions of NAFLD, and the cost and feasibility of known techniques are also important issues. Blood biomarkers for NAFLD may be useful to select subjects who need ultrasonography (US) screening for NAFLD, and noninvasive tools for assessing fibrosis may be helpful to exclude the probability of significant fibrosis and to predict advanced fibrosis, thus guiding the decision of whether to perform liver biopsy in patients with NAFLD. Among various methods, magnetic resonance-based methods have been shown to perform better than other methods in assessing steatosis as well as in detecting hepatic fibrosis. Many genetic markers are associated with the development and progression of NAFLD. Further well-designed studies are needed to determine which biomarker panels, imaging studies, genetic marker panels, or combinations thereof perform well for diagnosing NAFLD, differentiating NASH and fibrosis, and following-up NAFLD, respectively.

Non-Alcoholic Fatty Liver Disease in Patients with Type 2 Diabetes Mellitus: A Position Statement of the Fatty Liver Research Group of the Korean Diabetes Association

This clinical practice position statement, a product of the Fatty Liver Research Group of the Korean Diabetes Association, proposes recommendations for the diagnosis, progression and/or severity assessment, management, and follow-up of non-alcoholic fatty liver disease (NAFLD) in patients with type 2 diabetes mellitus (T2DM). Patients with both T2DM and NAFLD have an increased risk of non-alcoholic steatohepatitis (NASH) and fibrosis and a higher risk of cardiovascular diseases and diabetic complications compared to those without NAFLD. With regards to the evaluation of patients with T2DM and NAFLD, ultrasonography-based stepwise approaches using noninvasive biomarker models such as fibrosis-4 or the NAFLD fibrosis score as well as imaging studies such as vibration-controlled transient elastography with controlled attenuation parameter or magnetic resonance imaging-proton density fat fraction are recommended. After the diagnosis of NAFLD, the stage of fibrosis needs to be assessed appropriately. For management, weight reduction achieved by lifestyle modification has proven beneficial and is recommended in combination with antidiabetic agent(s). Evidence that some antidiabetic agents improve NAFLD/NASH with fibrosis in patients with T2DM is emerging. However, there are currently no definite pharmacologic treatments for NAFLD in patients with T2DM. For specific cases, bariatric surgery may be an option if indicated.

Guidelines on the management of abnormal liver blood tests

These updated guidelines on the management of abnormal liver blood tests have been commissioned by the Clinical Services and Standards Committee (CSSC) of the British Society of Gastroenterology (BSG) under the auspices of the liver section of the BSG. The original guidelines, which this document supersedes, were written in 2000 and have undergone extensive revision by members of the Guidelines Development Group (GDG). The GDG comprises representatives from patient/carer groups (British Liver Trust, Liver4life, PBC Foundation and PSC Support), elected members of the BSG liver section (including representatives from Scotland and Wales), British Association for the Study of the Liver (BASL), Specialist Advisory Committee in Clinical Biochemistry/Royal College of Pathology and Association for Clinical Biochemistry, British Society of Paediatric Gastroenterology, Hepatology and Nutrition (BSPGHAN), Public Health England (implementation and screening), Royal College of General Practice, British Society of Gastrointestinal and Abdominal Radiologists (BSGAR) and Society of Acute Medicine. The quality of evidence and grading of recommendations was appraised using the AGREE II tool. These guidelines deal specifically with the management of abnormal liver blood tests in children and adults in both primary and secondary care under the following subheadings: (1) What constitutes an abnormal liver blood test? (2) What constitutes a standard liver blood test panel? (3) When should liver blood tests be checked? (4) Does the extent and duration of abnormal liver blood tests determine subsequent investigation? (5) Response to abnormal liver blood tests. They are not designed to deal with the management of the underlying liver disease.

Landmarks in research of nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) has become the leading cause of chronic liver disease all over the world, which places a crushing burden on public health. During the past three decades, steady progress has been made in the evolving concepts of NAFLD, novel diagnostic methods to stage liver steatosis and fibrosis progression, and new pharmacological approaches for disease treatment, which have contributed to a revolutionary success. However, effective preventive and therapeutic strategies are still urgently needed. A better understanding of the research history of NAFLD will be helpful for its scientific prevention and treatment. In this review, we will discuss the progress in the understanding of the epidemiology, diagnosis, treatment, and pathogenesis of NAFLD.

Genetic and clinical markers of elevated liver fat content in overweight and obese Hispanic children

OBJECTIVE

Genetic variation in six genes has been associated with elevated liver fat and nonalcoholic fatty liver disease in adults. The influence of these genes on liver fat and whether a genetic risk score (GRS) would improve upon the ability of common clinical risk factors to predict elevated liver fat content (ELF) in Hispanic children was determined.

DESIGN AND METHODS

223 obese Hispanic children were genotyped for six SNPs. MRI was used to measure liver fat. A GRS was tested for association with ELF using multivariate linear regression. Predictors were assessed via ROC curves and pair-wise analysis was used to determine significance alone and combined with clinical markers.

RESULTS

Only variants in PNPLA3 and APOC3 genes were associated with liver fat (P < 0.001, P = 0.01, respectively). Subjects with a GRS = 4 had ∼3-fold higher liver fat content than subjects with GRS of 0 (15.1 ± 12.7 vs. 5.1 ± 3.7%, P = 0.03). While the addition of the GRS to a model containing BMI and liver enzymes increased ROC AUC from 0.83 to 0.85 [95% CI, 0.79-0.89], (P = 0.01), it does not improve detection of ELF from a clinical perspective.

CONCLUSIONS

Only PNPLA3 and APOC3 were related to ELF and a GRS comprised of these susceptibility alleles did not add to the discriminatory power of traditional biomarkers for clinical assessment of liver fat.

Synergistic association between alcohol intake and body mass index with serum alanine and aspartate aminotransferase levels in older adults: the Rancho Bernardo Study

BACKGROUND

The association between body-mass-index (BMI), alcohol consumption and their joint effect in increasing the risk of elevated serum alanine (ALT) and aspartate (AST) is unclear in older community-dwelling adults.

AIM

To determine the association between alcohol, BMI, and their combined effect with serum ALT and AST in older community-dwelling adults in the United States.

METHODS

A cross-sectional, population-based study in participants (n = 2364) from the Rancho Bernardo Study (54% women; mean age: 70 years, BMI: 25 kg/m(2), alcohol users: 63%) who attended a research visit in 1984-87. BMI was recorded by a trained nurse and alcohol use ascertained by a validated questionnaire. Odds-ratio (OR) and 95% confidence intervals (CI) of elevated serum ALT and AST (defined as > or =30 U/L in men and > or =19 U/L in women) were calculated for alcohol and BMI separately and their joint exposure using logistic regression models.

RESULTS

In multivariate logistic regression models adjusted for age, alcohol use, total cholesterol, serum triglycerides, fasting plasma glucose, systolic blood pressure, and diabetes mellitus, obesity independently increased the odds of elevated ALT in this cohort of older men and women by 3.0 (95% CI, 1.7-5.3) and 1.8 (95% CI, 1.1-2.7) respectively. Joint effects of consuming >3 alcoholic drinks/day and obesity raised the odds of elevated ALT by 8.9 (95% CI, 2.4-33.1) and AST by 21-fold (95% CI, 2.6-170.1), demonstrating synergism. Obese participants had higher odds of elevated ALT even at 0 < or = 1 drink/day.

CONCLUSIONS

In older men and women, the combination of obesity with alcohol is synergistic in increasing the risk of liver injury.