Imaging techniques for assessing hepatic fat content in nonalcoholic fatty liver disease

Metabolic-associated fatty liver voxel-based quantification on CT images using a contrast adapted automatic tool

BACKGROUND & AIMS

Metabolic-dysfunction associated fatty liver disease (MAFLD) is highly prevalent and can lead to liver complications and comorbidities, with non-invasive tests such as vibration-controlled transient elastography (VCTE) and invasive liver biopsies being used for diagnosis The aim of the present study was to develop a new fully automatized method for quantifying the percentage of fat in the liver based on a voxel analysis on computed tomography (CT) images to solve previously unconcluded diagnostic deficiencies either in contrast (CE) or non-contrast enhanced (NCE) assessments.

METHODS

Liver and spleen were segmented using nn-UNet on CE- and NCE-CT images. Radiodensity values were obtained for both organs for defining the key benchmarks for fatty liver assessment: liver mean, liver-to-spleen ratio, liver-spleen difference, and their average. VCTE was used for validation. A classification task method was developed for detection of suitable patients to fulfill maximum reproducibility across cohorts and highlight subjects with other potential radiodensity-related diseases.

RESULTS

Best accuracy was attained using the average of all proposed benchmarks being the liver-to-spleen ratio highly useful for CE and the liver-to-spleen difference for NCE. The proposed whole-organ automatic segmentation displayed superior potential when compared to the typically used manual region-of-interest drawing as it allows to accurately obtain the percent of fat in liver, among other improvements. Atypical patients were successfully stratified through a function based on biochemical data.

CONCLUSIONS

The developed method tackles the current drawbacks including biopsy invasiveness, and CT-related weaknesses such as lack of automaticity, dependency on contrast agent, no quantification of the percentage of fat in liver, and limited information on region-to-organ affectation. We propose this tool as an alternative for individualized MAFLD evaluation by an early detection of abnormal CT patterns based in radiodensity whilst abording detection of non-suitable patients to avoid unnecessary exposure to CT radiation. Furthermore, this work presents a surrogate aid for assessing fatty liver at a primary assessment of MAFLD using elastography data.

Drug-Induced Fatty Liver Disease (DIFLD): A Comprehensive Analysis of Clinical, Biochemical, and Histopathological Data for Mechanisms Identification and Consistency with Current Adverse Outcome Pathways

Drug induced fatty liver disease (DIFLD) is a form of drug-induced liver injury (DILI), which can also be included in the more general metabolic dysfunction-associated steatotic liver disease (MASLD), which specifically refers to the accumulation of fat in the liver unrelated to alcohol intake. A bi-directional relationship between DILI and MASLD is likely to exist: while certain drugs can cause MASLD by acting as pro-steatogenic factors, MASLD may make hepatocytes more vulnerable to drugs. Having a pre-existing MASLD significantly heightens the likelihood of experiencing DILI from certain medications. Thus, the prevalence of steatosis within DILI may be biased by pre-existing MASLD, and it can be concluded that the genuine true incidence of DIFLD in the general population remains unknown. In certain individuals, drug-induced steatosis is often accompanied by concomitant injury mechanisms such as oxidative stress, cell death, and inflammation, which leads to the development of drug-induced steatohepatitis (DISH). DISH is much more severe from the clinical point of view, has worse prognosis and outcome, and resembles MASH (metabolic-associated steatohepatitis), as it is associated with inflammation and sometimes with fibrosis. A literature review of clinical case reports allowed us to examine and evaluate the clinical features of DIFLD and their association with specific drugs, enabling us to propose a classification of DIFLD drugs based on clinical outcomes and pathological severity: Group 1, drugs with low intrinsic toxicity (e.g., ibuprofen, naproxen, acetaminophen, irinotecan, methotrexate, and tamoxifen), but expected to promote/aggravate steatosis in patients with pre-existing MASLD; Group 2, drugs associated with steatosis and only occasionally with steatohepatitis (e.g., amiodarone, valproic acid, and tetracycline); and Group 3, drugs with a great tendency to transit to steatohepatitis and further to fibrosis. Different mechanisms may be in play when identifying drug mode of action: (1) inhibition of mitochondrial fatty acid β-oxidation; (2) inhibition of fatty acid transport across mitochondrial membranes; (3) increased de novo lipid synthesis; (4) reduction in lipid export by the inhibition of microsomal triglyceride transfer protein; (5) induction of mitochondrial permeability transition pore opening; (6) dissipation of the mitochondrial transmembrane potential; (7) impairment of the mitochondrial respiratory chain/oxidative phosphorylation; (8) mitochondrial DNA damage, degradation and depletion; and (9) nuclear receptors (NRs)/transcriptomic alterations. Currently, the majority of, if not all, adverse outcome pathways (AOPs) for steatosis in AOP-Wiki highlight the interaction with NRs or transcription factors as the key molecular initiating event (MIE). This perspective suggests that chemical-induced steatosis typically results from the interplay between a chemical and a NR or transcription factors, implying that this interaction represents the primary and pivotal MIE. However, upon conducting this exhaustive literature review, it became evident that the current AOPs tend to overly emphasize this interaction as the sole MIE. Some studies indeed support the involvement of NRs in steatosis, but others demonstrate that such NR interactions alone do not necessarily lead to steatosis. This view, ignoring other mitochondrial-related injury mechanisms, falls short in encapsulating the intricate biological mechanisms involved in chemically induced liver steatosis, necessitating their consideration as part of the AOP's map road as well.

Association of non-alcoholic fatty liver disease with cardiovascular disease and all cause death in patients with type 2 diabetes mellitus: nationwide population based study

OBJECTIVE

To investigate the risk of non-alcoholic fatty liver disease (NAFLD) for cardiovascular disease and all cause death in patients with type 2 diabetes mellitus (T2DM).

DESIGN

Nationwide population based study.

SETTING

Longitudinal cohort study in Korea.

PARTICIPANTS

7 796 763 participants in the National Health Screening Programme in 2009 were divided into three groups based on NAFLD status: no NAFLD (fatty liver index<30); grade 1 NAFLD (30≤fatty liver index<60); and grade 2 NAFLD (fatty liver index≥60). Median follow-up was 8.13 years.

MAIN OUTCOME MEASURES

The primary outcome was incident cardiovascular disease (myocardial infarction, ischaemic stroke) or all cause death.

RESULTS

Of 7 796 763 participants, 6.49% (n=505 763) had T2DM. More patients with T2DM had grade 1 NAFLD (34.06%) and grade 2 NAFLD (26.73%) than those without T2DM (grade 1 NAFLD: 21.20%; grade 2 NAFLD: 10.02%). The incidence rate (per 1000 person years) of cardiovascular disease and all cause death increased in the order of no NAFLD, grade 1 NAFLD, and grade 2 NAFLD, and the incidence rates in patients with T2DM were higher than those in patients without T2DM. The five year absolute risk for cardiovascular disease and all cause death increased in the order of no NAFLD, grade 1 NAFLD, and grade 2 NAFLD in patients without and with T2DM (no NAFLD, without T2DM: 1.03, 95% confidence interval 1.02 to 1.04, and 1.25, 1.24 to 1.26, respectively; grade 1 NAFLD, without T2DM: 1.23, 1.22 to 1.25, and 1.50, 1.48 to 1.51, respectively; grade 2 NAFLD, without T2DM: 1.42, 1.40 to 1.45, and 2.09, 2.06 to 2.12, respectively; no NAFLD, with T2DM: 3.34, 3.27 to 3.41, and 3.68, 3.61 to 3.74, respectively; grade 1 NAFLD, with T2DM: 3.94, 3.87 to 4.02, and 4.25, 4.18 to 4.33, respectively; grade 2 NAFLD, with T2DM: 4.66, 4.54 to 4.78, and 5.91, 5.78 to 6.05, respectively). Patients with T2DM and without NAFLD had a higher five year absolute risk for cardiovascular disease and all cause death than those without T2DM and with grade 2 NAFLD. Risk differences for cardiovascular disease and all cause death between no NAFLD and grade 1 or grade 2 NAFLD were higher in patients with T2DM than in those without T2DM.

CONCLUSIONS

NAFLD in patients with T2DM seems to be associated with a higher risk of cardiovascular disease and all cause death, even in patients with mild NAFLD. Risk differences for cardiovascular disease and all cause death between the no NAFLD group and the grade 1 or grade 2 NAFLD groups were higher in patients with T2DM than in those without T2DM.

Metabolic-Associated Fatty Liver Disease and Diabetes: A Double Whammy

Metabolic-associated fatty liver disease (MAFLD) is the hepatic manifestation of metabolic syndrome and affects about 55% of people living with diabetes. MAFLD has been shown to be an individual risk factor for cardiovascular disease and its associated mortality. Although common, MAFLD is often underdiagnosed and not given adequate attention during clinical visits. This review highlights the most recent literature available on the evaluation and management of MAFLD in the presence of diabetes. The more recently available antidiabetic agents including glucagon-like peptide-1 analogs and sodium-glucose cotransporter-2 inhibitors have been shown to effectively manage both diabetes and MAFLD.

US Attenuation Imaging for the Evaluation and Diagnosis of Fatty Liver Disease

Purpose

This study aimed to determine whether the attenuation coefficient (AC) from attenuation imaging (ATI) was correlated with visual US assessment in patients with hepatic steatosis. Moreover, it aimed to assess whether the patient's blood chemistry results and CT attenuation were correlated with AC.

Materials and Methods

Patients who underwent abdominal US with ATI between April 2018 and December 2018 were included in this study. Patients with chronic liver disease or cirrhosis were excluded. The correlation between AC and other parameters, such as visual US assessment, blood chemistry results, liver attenuation, and liver-to-spleen (L/S) ratio, were analyzed. AC values according to visual US assessment grades were compared using analysis of variance.

Results

A total of 161 patients were included in this study. The correlation coefficient between US assessment and AC was 0.814 (p < 0.001). The mean AC values for the normal, mild, moderate, and severe grades were 0.56, 0.66, 0.74, and 0.85, respectively (p < 0.001). Alanine aminotransferase levels were significantly correlated with AC (r = 0.317, p < 0.001). The correlation coefficients between liver attenuation and AC and between L/S ratio and AC were -0.702 and -0.626, respectively (p < 0.001).

Conclusion

Visual US assessment and AC showed a strong positive correlation with the discriminative value between the groups. Computed tomography attenuation and AC showed a strong negative correlation.

Novel measures for the diagnosis of hepatic steatosis using contrast-enhanced computer tomography images

PURPOSE

Hepatic steatosis is often diagnosed non-invasively. Various measures and accompanying diagnostic thresholds based on contrast-enhanced CT and virtual non-contrast images have been proposed. We compare these established criteria to novel and fully automated measures.

METHOD

CT data sets of 197 patients were analyzed. Regions of interest (ROIs) were manually drawn for the liver, spleen, portal vein, and aorta to calculate four established measures of liver-fat. Two novel measures capturing the deviation between the empirical distributions of HU measurements across all voxels within the liver and spleen were calculated. These measures were calculated with both manual ROIs and using fully automated organ segmentations. Agreement between the different measures was evaluated using correlational analysis, as well as their ability to discriminate between fatty and healthy liver.

RESULTS

Established and novel measures of fatty liver were at a high level of agreement. Novel methods were statistically indistinguishable from the established ones when taking established diagnostic thresholds or physicians' diagnoses as ground truth and this high performance level persisted for automatically selected ROIs.

CONCLUSION

Automatically generated organ segmentations led to comparable results as manual ROIs, suggesting that the implementation of automated methods can prove to be a valuable tool for incidental diagnosis. Differences in the distribution of HU measurements across voxels between liver and spleen can serve as surrogate markers for the liver-fat-content. Novel measures do not exhibit a measurable disadvantage over established methods based on simpler measures such as across-voxel averages in a population with low incidence of fatty liver.

Development of de novo nonalcoholic fatty liver disease following pancreatectomy

De novo non-alcoholic fatty liver disease (NAFLD) after pancreatectomy is a recognized phenomenon; however, its pathophysiology is poorly understood. This study aimed to determine the incidence and identify peri-operative risk factors for the development of de novo NAFLD within various pancreatectomy groups. This single-center retrospective cohort study included patients who underwent pancreatectomy between 2000 and 2020. The incidence rate of de novo NAFLD and time to diagnosis were recorded across patients with malignant versus benign indications for pancreatectomy. The overall incidence of de novo NAFLD after pancreatectomy was 17.5% (24/136). Twenty-one percent (20/94) of patients with malignant indications for surgery developed NAFLD compared to 9.5% (4/42) with benign indications (P = .09). Time to development of hepatic steatosis in the malignant group was 26.4 months and was significantly shorter by an average of 6 months when compared to the benign group (32.8 months, P = .03). Higher pre-operative body mass index was associated with new-onset NAFLD (P = .03). Pre-operative body mass index is a significant predictor for de novo NAFLD and highlights a group that should be closely monitored post-operatively, especially after resections for pancreatic malignancy.

Regularized Ultrasound Phantom-Free Local Attenuation Coefficient Slope (ACS) Imaging in Homogeneous and Heterogeneous Tissues

Attenuation maps or measurements based on the local attenuation coefficient slope (ACS) in quantitative ultrasound (QUS) have shown potential for the diagnosis of liver steatosis. In liver cancers, tissue abnormalities and tumors detected using ACS are also of interest to provide new image contrast to clinicians. Current phantom-based approaches have the limitation of assuming a comparable speed of sound between the reference phantom and insonified tissues. Moreover, these methods present the inconvenience for operators to acquire data on phantoms and patients. The main goal was to alleviate these drawbacks by proposing a methodology for constructing phantom-free regularized (PF-R) local ACS maps and investigate the performance in both homogeneous and heterogeneous media. The proposed method was tested on two tissue-mimicking media with different ACS constructed as homogeneous phantoms, side-by-side and top-to-bottom phantoms, and inclusion phantoms with different attenuations. Moreover, an in vivo proof-of-concept was performed on healthy, steatotic, and cancerous human liver datasets. Modifications brought to previous works include: 1) a linear interpolation of the power spectrum in the log scale; 2) the relaxation of the underlying hypothesis on the diffraction factor; 3) a generalization to nonhomogeneous local ACS; and 4) an adaptive restriction of frequencies to a more reliable range than the usable frequency range. Regularization was formulated as a generalized least absolute shrinkage and selection operator (LASSO), and a variant of the Bayesian information criterion (BIC) was applied to estimate the Lagrangian multiplier on the LASSO constraint. In addition, we evaluated the proposed algorithm when applying median filtering before and after regularization. Tests conducted showed that the PF-R yielded robust results in all tested conditions, suggesting potential for additional validation as a diagnosis method.

Steatosis Grading Comparison Between Qualitative Ultrasonography and Magnetic Resonance Spectroscopy in Patients With Nonalcoholic Fatty Liver Disease

Objective:

Assess the correlation between the qualitative sonographic score for detecting hepatic steatosis (HS) and liver fat quantification, using proton magnetic resonance spectroscopy (MRS).

Materials and Methods:

Sixty-six patients with known or suspected nonalcoholic fatty liver disease (NAFLD) underwent ultrasonography (US) and magnetic resonance imaging (MRI). The qualitative sonographic score and fat quantification, measured by MRS, were the techniques used. A Kappa coefficient was used for agreement calculation, and a Fisher test was used to assess the normality of the variables. The MRS results were the gold standard for US quality assessment.

Results:

The agreement between MRS and US was 50% (Kappa 0.35). Ultrasonography results were more severe in 42.4% of the cases, and 66.7% of the patients had a body mass index greater than 30 ( P = .017). For diagnosis of HS, US presented 100% sensitivity, 30.8% to 60% specificity, 61.7% to 72.7% accuracy, 40% to 69.2% false-positive rate, 0% false-negative rate, 53.8% positive predictive value, and 100% negative predictive value.

Conclusion:

Ultrasonography is a reliable exam for detecting HS, although not for grading purposes. Therefore, US is not a good predictor of HS severity for the management and follow-up of NAFLD.

Effects of Thyroid Hormones on Lipid Metabolism Pathologies in Non-Alcoholic Fatty Liver Disease

The typical modern lifestyle contributes to the development of many metabolic-related disorders, as exemplified by metabolic syndrome. How to prevent, resolve, or avoid subsequent deterioration of metabolic disturbances and the development of more serious diseases has become an important and much-discussed health issue. Thus, the question of the physiological and pathological roles of thyroid hormones (THs) in metabolism has never gone out of fashion. Although THs influence almost all organs, the liver is one of the most important targets as well as the hub of metabolic homeostasis. When this homeostasis is out of balance, diseases may result. In the current review, we summarize the common features and actions of THs, first focusing on their effects on lipid metabolism in the liver. In the second half of the review, we turn to a consideration of non-alcoholic fatty liver disease (NAFLD), a disease characterized by excessive accumulation of fat in the liver that is independent of heavy alcohol consumption. NAFLD is a growing health problem that currently affects ~25% of the world’s population. Unfortunately, there are currently no approved therapies specific for NAFLD, which, if left uncontrolled, may progress to more serious diseases, such as cirrhosis or liver cancer. This absence of effective treatment can also result in the development of non-alcoholic steatohepatitis (NASH), an aggressive form of NAFLD that is the leading cause of liver transplantation in the United States. Because THs play a clear role in hepatic fat metabolism, their potential application in the prevention and treatment of NAFLD has attracted considerable research attention. Studies that have investigated the use of TH-related compounds in the management of NAFLD are also summarized in the latter part of this review. An important take-home point of this review is that a comprehensive understanding of the physiological and pathological roles of THs in liver fat metabolism is possible, despite the complexities of this regulatory axis—an understanding that has clinical value for the specific management of NAFLD.

Association between Physical Activity and Non-Alcoholic Fatty Liver Disease in Adults with Metabolic Syndrome: The FLIPAN Study

Background: A lifestyle with regular PA (physical activity) and Mediterranean diet has benefits on NAFLD (non-alcoholic fatty liver disease) and MetS (metabolic syndrome). Objectives: To assess the association between physical activity and NAFLD in adults with MetS. Design: Cross-sectional study in 155 participants (40−60 years old) from Balearic Islands and Navarra (Spain) with diagnosis of NAFLD and MetS, and BMI (body mass index) between 27 and 40 Kg/m2. Methods: PA level was categorized into two groups according to weekly METs (metabolic equivalents of tasks). PA was assessed using a validated Minnesota questionnaire and accelerometers. MetS parameters were assessed by blood collection analysis and NAFLD by abdominal MRI (magnetic resonance imaging). Results: Participants with high PA showed more energy expenditure and expended more calories than ingested (−143.9 Kcal/day; p < 0.001). PA was a risk factor for AST (aspartate aminotransferase) (adjusted OR: 7.26; 95% CI: 1.79−29.40) and a protective factor for ALT (alanine aminotransferase) (adjusted OR: 0.24; 95% CI: 0.12−0.48), GGT (gamma-glutamyl transferase) (adjusted OR: 0.52; 95% CI: 0.29−0.94) and IFC-NMR (intrahepatic fat content by nuclear magnetic resonance) (adjusted OR: 0.26; 95% CI: 0.12−0.56) when sociodemographic confounders were considered. Conclusions: NAFLD patients with high PA showed more positive relationship on MetS parameters and liver profile (ALT, GGT, IFC-NMR) than subjects with low PA, but not for AST. Difference between calories ingested and expended influenced this relationship.

Periodontal disease-related nonalcoholic fatty liver disease and nonalcoholic steatohepatitis: An emerging concept of oral-liver axis

Periodontal disease, a chronic inflammatory disease of the periodontal tissues, is not only a major cause of tooth loss, but it is also known to exacerbate/be associated with various metabolic disorders, such as obesity, diabetes, dyslipidemia, and cardiovascular disease. Recently, growing evidence has suggested that periodontal disease has adverse effects on the pathophysiology of liver disease. In particular, nonalcoholic fatty liver disease, a hepatic manifestation of metabolic syndrome, has been associated with periodontal disease. Nonalcoholic fatty liver disease is characterized by hepatic fat deposition in the absence of a habitual drinking history, viral infections, or autoimmune diseases. A subset of nonalcoholic fatty liver diseases can develop into more severe and progressive forms, namely nonalcoholic steatohepatitis. The latter can lead to cirrhosis and hepatocellular carcinoma, which are end‐stage liver diseases. Extensive research has provided plausible mechanisms to explain how periodontal disease can negatively affect nonalcoholic fatty liver disease and nonalcoholic steatohepatitis, namely via hematogenous or enteral routes. During periodontitis, the liver is under constant exposure to various pathogenic factors that diffuse systemically from the oral cavity, such as bacteria and their by‐products, inflammatory cytokines, and reactive oxygen species, and these can be involved in disease promotion of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis. Also, gut microbiome dysbiosis induced by enteral translocation of periodontopathic bacteria may impair gut wall barrier function and promote the transfer of hepatotoxins and enterobacteria to the liver through the enterohepatic circulation. Moreover, in a population with metabolic syndrome, the interaction between periodontitis and systemic conditions related to insulin resistance further strengthens the association with nonalcoholic fatty liver disease. However, most of the pathologic links between periodontitis and nonalcoholic fatty liver disease in humans are provided by epidemiologic observational studies, with the causal relationship not yet being established. Several systematic and meta‐analysis studies also show conflicting results. In addition, the effect of periodontal treatment on nonalcoholic fatty liver disease has hardly been studied. Despite these limitations, the global burden of periodontal disease combined with the recent nonalcoholic fatty liver disease epidemic has important clinical and public health implications. Emerging evidence suggests an association between periodontal disease and liver diseases, and thus we propose the term periodontal disease–related nonalcoholic fatty liver disease or periodontal disease–related nonalcoholic steatohepatitis. Continued efforts in this area will pave the way for new diagnostic and therapeutic approaches based on a periodontologic viewpoint to address this life‐threatening liver disease.

Non-Alcoholic Fatty Liver Disease in Obese Youth With Insulin Resistance and Type 2 Diabetes

Currently, Non-Alcoholic Fatty Liver Disease (NAFLD) is the most prevalent form of chronic liver disease in children and adolescents worldwide. Simultaneously to the epidemic spreading of childhood obesity, the rate of affected young has dramatically increased in the last decades with an estimated prevalence of NAFLD of 3%-10% in pediatric subjects in the world. The continuous improvement in NAFLD knowledge has significantly defined several risk factors associated to the natural history of this complex liver alteration. Among them, Insulin Resistance (IR) is certainly one of the main features. As well, not surprisingly, abnormal glucose tolerance (prediabetes and diabetes) is highly prevalent among children/adolescents with biopsy-proven NAFLD. In addition, other factors such as genetic, ethnicity, gender, age, puberty and lifestyle might affect the development and progression of hepatic alterations. However, available data are still lacking to confirm whether IR is a risk factor or a consequence of hepatic steatosis. There is also evidence that NAFLD is the hepatic manifestation of Metabolic Syndrome (MetS). In fact, NAFLD often coexist with central obesity, impaired glucose tolerance, dyslipidemia, and hypertension, which represent the main features of MetS. In this Review, main aspects of the natural history and risk factors of the disease are summarized in children and adolescents. In addition, the most relevant scientific evidence about the association between NAFLD and metabolic dysregulation, focusing on clinical, pathogenetic, and histological implication will be provided with some focuses on the main treatment options.

Optimal thresholds for ultrasound attenuation parameter in the evaluation of hepatic steatosis severity: evidence from a cohort of patients with biopsy-proven fatty liver disease

OBJECTIVE

FibroTouch is a newly developed device to assess ultrasound attenuation parameter (UAP) and liver stiffness measurement to quantify hepatic steatosis and fibrosis, respectively. However, there is currently a lack of defined thresholds of UAP to diagnose different stages of hepatic steatosis. We aimed to assess the optimal thresholds of UAP for hepatic steatosis in individuals with biopsy-proven fatty liver disease (FLD).

METHODS

We enrolled 497 adults with FLD undergoing FibroTouch and liver biopsy. Area under the receiver operating characteristic curve (AUROC) was performed to calculate the performance of UAP in staging hepatic steatosis. Hepatic steatosis >33% was defined as significant steatosis. We determined the optimal cutoff values of UAP and the sensitivity or specificity higher than 90%. Sensitivity, specificity, positive predictive value and negative predictive value were subsequently calculated.

RESULTS

The median UAP for the enrolled patients was 308 dB/m. Multivariable logistic regression analysis showed that UAP was associated with significant steatosis [adjusted-odds ratio 1.05, 95% confidence interval (CI), 1.02-1.09; P = 0.001]. The AUROCs for S ≥ 1, S ≥ 2 and S = 3 were 0.88 (95% CI, 0.84-0.91), 0.77 (95% CI, 0.73-0.81), and 0.70 (95% CI, 0.63-0.77), respectively. The optimal UAP cutoffs were 295 dB/m for S ≥ 1, 314 dB/m for S ≥ 2, and 324 dB/m for S = 3. Almost identical results were observed in the subgroup of patients with biopsy-confirmed nonalcoholic fatty liver disease (n = 435).

CONCLUSION

We found that the AUROC values of UAP by FibroTouch were ranging from 0.70 to 0.88 for assessing hepatic steatosis severity. These UAP cutoffs could be applicable for clinical use.

Usefulness of US attenuation imaging for the detection and severity grading of hepatic steatosis in routine abdominal ultrasonography

PURPOSE

To assess the diagnostic performance of ultrasound (US) attenuation imaging (ATI) for diagnosis and grading of hepatic steatosis with comparison to magnetic resonance imaging-proton density fat fraction (MRI-PDFF) using mDIXON-Quant sequence.

METHODS

Total 100 patients who underwent abdominal US ATI and MRI-PDFF within one month were included. Subjects were divided into three groups according to MRI-PDFF; Group 1 (no fatty liver), Q < 5.1%; Group 2 (mild fatty liver), 5.1% ≤ Q < 14.1%; and Group 3 (moderate fatty liver), Q ≥ 14.1%. US attenuation coefficients (AC) of enrolled patients were measured and correlated with MRI-PDFF. And their diagnostic performances were assessed. AC, MRI-PDFF, and liver function tests were compared among all groups.

RESULTS

Mean AC value of each group was as follows: Group 1 = 0.58 ± 0.11 dB/cm/MHz, Group 2 = 0.68 ± 0.08 dB/cm/MHz, and Group 3 = 0.77 ± 0.06 dB/cm/MHz. Mean AC value of each group of hepatic steatosis showed statistically significant difference (p < 0.001). There was a significant correlation between AC and MRI-PDFF in Pearson correlation (r = 0.751, p < 0.001). The area under the ROC curve (AUROC) of AC was 0.914 with sensitivity of 91.5%, and specificity of 80.0% for detection of mild fatty liver, and 0.935 for detection of moderate fatty liver with sensitivity of 93.3%, and specificity of 87.1%.

CONCLUSION

AC using ultrasound ATI showed high diagnostic performance and provided discriminative values for severity grading of fatty liver disease.

Preventive Effect of High-Dose Digestive Enzyme Management on Development of Nonalcoholic Fatty Liver Disease after Pancreaticoduodenectomy: A Randomized Controlled Clinical Trial

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a complication of pancreaticoduodenectomy (PD). We conducted a randomized clinical trial to determine if high-dose digestive enzymes prevented the development of NAFLD after PD.

STUDY DESIGN

This parallel-group, nonblinded, multicenter study enrolled patients undergoing elective PD at Shinshu University School of Medicine, from June 2011 to April 2017. Patients were randomly assigned to receive normal-dose (Excelase: 3.0 g/day [Meiji Seika Pharma Holdings Co, Ltd]) or high-dose digestive enzyme treatment (Excelase: 3.0 g/day; Pancreatin [Tokyo Chemical Industry Co Ltd]: 3.0 g/day; Berizym [Kyowa Pharmaceutical Industry Co Ltd]: 3.0 g/day; and Toughmac-E [Ono Pharmaceutical Co, Ltd]: 3.0 g/day) within 1 week after surgery. Because patients in the control group switched interventions upon receiving a diagnosis of NAFLD, intention-to-treat analysis was used. The primary endpoint was incidence of NAFLD within 1 year, and the secondary endpoints were the incidences of NAFLD at 1, 3, 6, and 12 months and the rate of improvement in NAFLD with high-dose transfer in the control group. The secondary analysis comprised assessment of risk factors for the development of NAFLD.

RESULTS

Eighty-four patients were randomly assigned (42 per group), 80 of whom were finally analyzed (39 normal-dose, 41 high-dose). The incidence of NAFLD was significantly lower in the high-dose (8 of 41) compared with the normal-dose (25 of 39) patients (p < 0.001). Multivariate analysis identified normal-dose (odds ratio [OR] 14.65, p < 0.001), total protein ≤ 6.5g/dL (OR 9.01, p = 0.018), pre-albumin ≤ 22.0 mg/dL (OR 7.71, p = 0.018), and pancreatic function diagnostic test ≤ 70% (OR 6.66, p = 0.009) as independent risk factors. There were no adverse effects. The model was accurate (c-index = 0.92) and reliable (Hosmer-Lemeshow test p = 0.32).

CONCLUSIONS

High-dose administration of digestive enzymes significantly reduced the onset of NAFLD after PD compared with normal-dose administration. Registration number: UMIN000005595 (http://www.umin.ac.jp/ctr/).

Ultrasound Assessment of Hepatic Steatosis by Using the Double Nakagami Distribution: A Feasibility Study

Ultrasound imaging is a first-line assessment tool for hepatic steatosis. Properties of tissue microstructures correlate with the statistical distribution of ultrasound backscattered signals, which can be described by the Nakagami distribution (a widely adopted approximation of backscattered statistics). The double Nakagami distribution (DND) model, which combines two Nakagami distributions, was recently proposed for using high-frequency ultrasound to analyze backscattered statistics corresponding to lipid droplets in the fat-infiltrated liver. This study evaluated the clinical feasibility of the DND model in ultrasound parametric imaging of hepatic steatosis by conducting clinical experiments using low-frequency ultrasound dedicated to general abdominal examinations. A total of 204 patients were recruited, and ultrasound image raw data were acquired using a 3.5 MHz array transducer for DND parametric imaging using the sliding window technique. The DND parameters were compared with hepatic steatosis grades identified histologically. A receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance. The results indicated that DND parametric imaging constructed using a sliding window with the side length of five times the pulse length of the transducer provided stable and reliable DND parameter estimations and visualized changes in the backscattered statistics caused by hepatic steatosis. The DND parameter increased with the hepatic steatosis grade. The areas under the ROC curve for identifying hepatic steatosis were 0.76 (≥mild), 0.81 (≥moderate), and 0.82 (≥severe). When using low-frequency ultrasound, DND imaging allows the clinical detection of hepatic steatosis and reflects information associated with lipid droplets in the fat-infiltrated liver.

Genome-Wide Association Study of Lean Nonalcoholic Fatty Liver Disease Suggests Human Leukocyte Antigen as a Novel Candidate Locus

Nonalcoholic fatty liver disease (NAFLD) is supposed to manifest its metabolic phenotype in the liver, but it is common to have lean individuals diagnosed with NAFLD, known as lean NAFLD. We conducted a two-stage analysis to identify NAFLD-associated loci in Japanese patients. In stage I, 275 metabolically healthy normal-weight patients with NAFLD were compared with 1,411 non-NAFLD controls adjusted for age, sex, and alcohol consumption by a genome-wide association study (GWAS). In stage II, human leukocyte antigen (HLA) in chromosome 6 (chr6) (P = 6.73E-08), microRNA (MIR) MIR548F3 in chr7 (P = 4.25E-07), myosin light chain 2 (MYL2) in chr12 (P = 4.39E-07), and glycoprotein precursor (GPC)6 in chr13 (P = 5.43E-07), as suggested by the GWAS, were assessed by single nucleotide polymorphism (SNP) association analysis of whole NAFLD against non-NAFLD in 9,726 members of the general population. A minor allele of the secondary lead SNP in chr6, rs2076529, was significantly associated (odds ratio [OR], 1.19; 95% confidence interval [CI], 1.11-1.28; P = 2.10E-06) and the lead SNP in chr7 was weakly associated (OR 1.15; 95% CI, 1.04-1.27; P = 6.19E-03) with increased NAFLD risk. Imputation-based typing of HLA showed a significant difference in the distribution of HLA-B, HLA-DR-beta chain 1 (DRB1), and HLA-DQ-beta chain 1 (DQB1) alleles in lean NAFLD GWAS. Next-generation sequence-based typing of HLA in 5,649 members of the general population replicated the significant difference of HLA-B allele distribution and the significant increase of the HLA-B*54:01 allele in whole NAFLD. Fecal metagenomic analysis of 3,420 members of the general population showed significant dissimilarity in beta-diversity analysis of rs2076529 and HLA-B*54:01 allele carriers from noncarriers. Veillonellaceae was increased but Verrucomicrobia was decreased in rs2076529 minor allele and HLA-B*54:01 allele carriers as in NAFLD. Conclusion: HLA was identified as a novel locus associated with NAFLD susceptibility, which might be affected by the alteration of gut microbiota.

Overweight and obesity status from the prenatal period to adolescence and its association with non-alcoholic fatty liver disease in young adults: cohort study

OBJECTIVE

To examine the associations of maternal and child overweight status across multiple time-points with liver fat content in the offspring during young adulthood.

DESIGN

Cohort study.

SETTING

ELEMENT Cohort in Mexico City.

POPULATION

Pregnant women with singleton births (n = 97).

METHODS

We quantified hepatic triglyceride content (liver fat content) by proton magnetic resonance spectroscopy (1H MRS) and conventional T2-weighted MRIs (3T scanner) in 97 young adults from the ELEMENT birth cohort in Mexico City. Historical records of the cohort were used as a source of pregnancy, and childhood and adolescence anthropometric information, overweight and obesity (OWOB) were defined. Adjusted structural equation models were run to identify the association between OWOB in different life stages with liver fat content (log-transformed) in young adulthood.

MAIN OUTCOME

Maternal OWOB at the time of delivery was directly and indirectly associated with the liver fat content in the offspring at young adulthood.

RESULTS

Seventeen percent of the participants were classified as having NAFLD. We found a strong association of OWOB between all periods assessed. Maternal OWOB at time of delivery (β = 1.97, 95% CI 1.28-3.05), and OWOB status in the offspring at young adulthood (β = 3.17, 95% CI 2.10-4.77) were directly associated with the liver fat content in the offspring. Also, maternal OWOB was indirectly associated with liver fat content through offspring OWOB status.

CONCLUSION

We found that maternal OWOB status is related to fatty liver content in the offspring as young adults, even after taking into account OWOB status and lifestyle factors in the offspring.

TWEETABLE ABSTRACT

There was an association between pre-pregnancy overweight and the development of NAFLD in adult offspring.

Noninvasive Imaging Modalities in Nonalcoholic Fatty Liver Disease: Where Do We Stand?

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. Liver biopsy is the gold standard for diagnosis and staging of fibrosis in patients with NAFLD; however, it is invasive, costly, and may be associated with morbidity and even mortality, so is not suitable for screening the large number of individuals who are at risk of, or have, NAFLD. Therefore, there has been tremendous focus on finding noninvasive diagnostic modalities, including imaging. New imaging modalities are emerging and may potentially replace biopsy. This review discusses the different noninvasive imaging modalities for the assessment of NAFLD.

Effect of Sodium Glucose Co-Transporter 2 Inhibitors on Liver Fat Mass and Body Composition in Patients with Nonalcoholic Fatty Liver Disease and Type 2 Diabetes Mellitus

BACKGROUND AND OBJECTIVE

Sodium glucose co-transporter 2 inhibitors increase urinary glucose excretion and reduce visceral adiposity and body weight, but their efficacy on patients with nonalcoholic fatty liver disease has not been sufficiently investigated. The aim of this study was to assess the effect of sodium glucose co-transporter 2 inhibitors on liver fat mass and body composition in patients with nonalcoholic fatty liver disease and type 2 diabetes mellitus.

METHODS

We retrospectively analyzed 17 patients with nonalcoholic fatty liver disease and type 2 diabetes who received sodium glucose co-transporter 2 inhibitors between November 2016 and July 2017. Changes in liver fat, subcutaneous and visceral fat, body composition, and liver function-related parameters were assessed after 24 weeks of sodium glucose co-transporter 2 inhibitor treatment and compared to baseline values.

RESULTS

Ten patients received dapagliflozin at 5 mg/day and seven patients received canagliflozin at 100 mg/day for 24 weeks. All patients completed the study without any serious adverse effects and achieved body weight loss and improved glycated hemoglobin levels. Liver fat mass evaluated by proton magnetic resonance spectroscopy was significantly reduced (19.1% vs. 9.2%, p < 0.01), and so were both subcutaneous and visceral fat mass. The body fat/body weight ratio decreased, whereas the skeletal muscle mass/body weight ratio increased. Liver function (aspartate aminotransferase, alanine aminotransferase, and γ-glutamyl transpeptidase) improved significantly.

CONCLUSIONS

Sodium glucose co-transporter 2 inhibitor treatment not only improved glycemic control but also reduced liver fat mass in patients with nonalcoholic fatty liver disease and type 2 diabetes. Body weight loss was primarily attributable to a reduction in fat mass, especially visceral fat. Thus, sodium glucose co-transporter 2 inhibitors could potentially serve as a therapeutic agent for patients with nonalcoholic fatty liver disease and type 2 diabetes.

Accuracy of ultrasonography in the assessment of liver fat compared with MRI

AIM

To investigate the accuracy of ultrasonography in the assessment of hepatic steatosis using magnetic resonance imaging (MRI) as standard of reference and to explore the influence of additional hepatic iron overload.

MATERIAL AND METHODS

A total of 2,783 volunteers (1,442 women, 1,341 men; mean age, 52.3±13.8 years) underwent confounder-corrected chemical-shift-encoded MRI of the liver at 1.5 T. Proton-density fat fraction (PDFF) and transverse relaxation rate (R2*) were calculated to estimate hepatic steatosis and liver iron overload, respectively. In addition, the presence of hepatic steatosis was assessed by B-mode ultrasonography. The sensitivity, specificity, and accuracy of hepatic ultrasonography were determined for different degrees of hepatic steatosis and different amounts of liver iron.

RESULTS

MRI revealed hepatic steatosis in 40% of participants (n=1,112), which was mild in 68.9% (n=766), moderate in 26.7% (n=297), and severe in 4.4% (n=49) of patients. Ultrasonography detected hepatic steatosis in 37.8% (n=1,052), corresponding to 74.5% sensitivity and 86.6% specificity. The sensitivity of ultrasound increased with the amount of hepatic fat present and was 65.1%, 95%, and 96% for low, moderate, and high fat content; whereas the specificity was constantly high at 86.6%. The diagnostic accuracy of ultrasound for detection of hepatic steatosis did not vary significantly with the amount of liver iron present.

CONCLUSION

Ultrasonography is an excellent tool to assess hepatic steatosis in the clinical setting with some limitations in patients with a low liver fat content. The detection of hepatic steatosis by ultrasonography is not influenced by liver iron.

Dietary Sources of Fructose and Its Association with Fatty Liver in Mexican Young Adults

Fructose intake has been associated with non-alcoholic fatty liver disease (NAFLD). The objective of this study was to assess the consumption of dietary fructose according to: 1) classification of hepatic steatosis by two indexes and 2) diagnosis of NAFLD by MRI. We conducted a cross-sectional analysis among 100 young adults from Mexico City. The Hepatic Steatosis Index (HSI) and the Fatty Liver Index (FLI) were estimated using Body Mass Index (BMI), waist circumference, and fasting concentrations of glucose, triglycerides, and hepatic enzymes (ALT, AST, GGT). A semi-quantitative food frequency questionnaire was administered to obtain dietary sources of fructose. We estimated the concordance between the hepatic indices and NAFLD and the correlation between the index scores and the percentage of liver fat. Eighteen percent presented NAFLD; 44% and 46% were classified with hepatic steatosis according to HSI and FLI, respectively. We compared dietary intake of fructose by each outcome: HSI, FLI, and NAFLD. Sugar-sweetened beverages (SSB) and juices were consumed significantly more by those with steatosis by FLI and NAFLD suggesting that SSB intake is linked to metabolic alterations that predict the risk of having NAFLD at a young age.

Ratio of muscle mass to fat mass assessed by bioelectrical impedance analysis is significantly correlated with liver fat accumulation in patients with type 2 diabetes mellitus

AIMS

Obesity and ectopic fat accumulation are important conditions of type 2 diabetes mellitus (T2DM). Our aim was to determine whether bioelectrical impedance body composition analysis combined with blood test results could estimate liver ectopic fat accumulation in patients with treatment-naïve T2DM.

METHODS

Subjects were 119 untreated T2DM patients. Computed tomography scans were performed to calculate the liver to spleen attenuation ratio (L/S ratio) as a measure of liver fat accumulation, with excess liver fat accumulation defined as an L/S ratio <1.0. Elementary body composition was measured by bioelectrical impedance analysis using InBody770.

RESULTS

The Nagelkerke R² test showed that the muscle mass/fat mass ratio (muscle/fat ratio) was the most suitable variable among anthropometric factors and body component indexes for estimating liver fat accumulation. The muscle/fat ratio was significantly correlated with the L/S ratio (ρ = 0.4386, P < 0.0001). Multivariable logistic regression analysis showed that the muscle/fat ratio (odds ratio 0.40, 95% confidence interval 0.22-0.73, P < 0.01) and alanine aminotransferase (odds ratio 1.06, 95% confidence interval 1.02-1.10, P < 0.01) were independently and significantly associated with liver fat accumulation. In receiver operating characteristic curve analysis, the cutoff value of the muscle/fat ratio for excess liver fat accumulation was 2.34.

CONCLUSION

In patients with treatment-naïve T2DM, the muscle/fat ratio and ALT are useful for estimating the presence of excess liver fat accumulation in daily clinical practice.

Clinical usefulness of controlled attenuation parameter to screen hepatic steatosis for potential donor of living donor liver transplant

OBJECTIVE

Hepatic steatosis is associated with an increased risk of graft loss. Although the controlled attenuation parameter (CAP), a process based on transient elastography, has been suggested as a noninvasive method of assessing hepatic steatosis, to date, there is no study on the usefulness of CAP as a single screening tool for detecting hepatic steatosis in potential living donor liver. We evaluated the accuracy of CAP for detecting hepatic steatosis in potential liver donors.

PATIENTS AND METHODS

All potential donors of living-donor liver transplantation who underwent a CAP assessment and ultrasonography-guided liver biopsy were enrolled. The steatosis grades were as follows: S0 less than 5%; S1, 5-33%; S2, 34-66%; and S3, more than 66%.

RESULTS

According to the liver biopsies, 19 (34.5%) patients had S0, 30 (54.5%) patients had S1, and 6 (11.0%) patients had S2. The CAP value was correlated positively with BMI (r=0.242, P=0.01), waist circumference (r=0.268, P=0.006), hip circumference (r=0.334, P=0.001), Magnetic resonance fat signal fraction (r=0.465, P=0.001), and histologic steatosis grade (r=0.542, P=0.001). The area under the receiver operator characteristic curve for the diagnosis of steatosis (≥S2) by CAP was 0.88 (sensitivity 83.3% and specificity 81.6% at a cutoff value of 276 dB/m, P<0.0001).

CONCLUSION

This study suggests that CAP, as a simple and noninvasive preoperative assessment for hepatic steatosis, may be sufficient for identifying and thus excluding significant hepatic steatosis (>33%) in potential liver donors.

Feline Hepatic Lipidosis

Feline hepatic lipidosis (FHL) is a common and potentially fatal liver disorder. Although the pathophysiologic mechanisms of FHL remain elusive, there is an imbalance between the influx of fatty acids from peripheral fat stores into the liver, de novo liposynthesis, and the rate of hepatic oxidation and dispersal of hepatic TAG via excretion of very-low density lipoproteins. The diagnosis of FHL is based on anamnestic, clinical, and clinicopathologic findings, associated with diagnostic imaging of the liver, and cytology, or histological examination of liver biopsies. Fluid therapy, electrolyte correction and adequate early nutrition are essential components of the therapy for FHL.

Diagnosis and quantification of fibrosis, steatosis, and hepatic siderosis through multiparametric magnetic resonance imaging

BACKGROUND

The presence of liver fibrosis is the common denominator in numerous chronic liver diseases that can progress to fibrosis and hepatocellular carcinoma. Most important, with respect to frequency, are viral hepatitis and non-alcoholic fatty liver disease, the prevalence of which is increasing in epidemic proportions. Liver biopsy, albeit imperfect, continues to be the criterion standard, but in many clinical situations tends to be replaced with noninvasive imaging methods.

OBJECTIVES

The aim of the present article was to describe our imaging department experience with magnetic resonance elastography and to analyze and discuss recently published results in gastroenterology, hepatology, and radiology from other authors in the literature, complemented with a PubMed search covering the last 10 years.

RESULTS AND CONCLUSIONS

Magnetic resonance elastography is an efficacious, noninvasive method with results that are concordant with liver biopsy. It is superior to ultrasound elastography because it evaluates a much greater volume of hepatic tissue and shows the often heterogeneous lesion distribution. The greatest advantage of the magnetic resonance protocol described is the fact that it quantifies fibrosis, fat content, and iron content in the same 25min examination specifically directed for that purpose, resulting in a favorable cost-benefit ratio for the patient and/or institution.

Prevalence of hepatic steatosis in apparently healthy medical students: a transient elastography study on the basis of a controlled attenuation parameter

OBJECTIVE

Despite the increasing burden of nonalcoholic fatty liver disease (NAFLD) in modern societies, the optimal screening method to detect hepatic steatosis in the general population remains to be established. Controlled attenuation parameter (CAP) measured with transient elastography (TE) has recently emerged as a reliable imaging tool for the screening and diagnosis of NAFLD. Here, we sought to investigate the prevalence of TE-defined hepatic steatosis in a sample of apparently healthy medical students. We also assessed the relationships between CAP and traditional NAFLD risk factors.

MATERIALS AND METHODS

A total of 112 Turkish medical students (48 women and 64 men, mean age 20.5±1.1 years) underwent TE. On the basis of previous studies, a cut-off value of 238 dB/m for CAP was used for the diagnosis of hepatic steatosis.

RESULTS

On the basis of the selected cut-off for CAP, we identified 26 students (23.2%) with TE-defined NAFLD. Univariate correlation analyses showed that CAP values were significantly associated with BMI (r=0.40, P<0.001), waist circumference (r=0.39, P<0.001), and hip circumference (r=0.34, P<0.001). In multivariable analysis, only BMI retained its independent association with CAP (β=0.36, t=3.4, P<0.001).

CONCLUSION

NAFLD is highly prevalent even in apparently healthy young individuals. CAP assessment with TE may be useful for an early, noninvasive identification of hepatic steatosis.

Associations among the Degree of Nonalcoholic Fatty Liver Disease, Metabolic Syndrome, Degree of Obesity in Children, and Parental Obesity

PURPOSE

To analyze the associations among the degrees of nonalcoholic fatty liver disease (NAFLD) by ultrasonography and metabolic syndrome, degrees of obesity in children, and degrees of parental obesity.

METHODS

A total of 198 children with obesity who visited a pediatric obesity clinic were prospectively enrolled in this study. The severity of NAFLD based on ultrasonography was classified into no, mild, moderate, or severe NAFLD group. The degree of obesity based on the percentage over standard weight for height per sex was classified into mild, moderate, or severe.

RESULTS

Of 132 patients evaluated for the degree of NAFLD and metabolic syndrome, the p-value of correlation between the two factors was 0.009. Therefore, metabolic syndrome might significantly affect the degree of NAFLD. Of 158 patients evaluated for the degree of NAFLD and the degree of obesity, the p-value of correlation between the two factors was 0.122. Of 154 patients evaluated for the degree of obesity and father's obesity, the p-value was 0.076. Of 159 patients evaluated for the degree of obesity and mother's obesity, the p-value was 0.000, indicating that mother's obesity could significantly affect the degree of obesity in children. Of 142 patients evaluated for the degree of obesity and metabolic syndrome, the p-value was 0.288.

CONCLUSION

Metabolic syndrome might significantly affect the degree of nonalcoholic fatty liver in children. In addition, mother's obesity might be a significant factor that affects the degree of obesity in children.

Prevalence and risk factors of nonalcoholic fatty liver disease in breast cancer patients

AIMS AND BACKGROUND

We aimed to evaluate the prevalence of nonalcoholic fatty liver disease (NAFLD) in breast cancer patients using liver magnetic resonance imaging (MRI), and to investigate factors associated with NAFLD.

METHODS

We evaluated 104 patients surgically treated for breast cancer at our hospital between September and November 2013. None of the patients had any other causes of secondary hepatic fat accumulation (such as significant alcohol consumption, use of steatogenic medication or inborn disorders). Hepatic fat accumulation was measured using liver MRI perfomed in all patients before surgical treatment.

RESULTS

Based on the fat signal percentage from liver MRIs, 19 of 104 breast cancer patients were diagnosed with NAFLD, so the prevalence of NAFLD was 18.3%. In univariate analysis, factors associated with NAFLD were older age, high body mass index, type 2 diabetes mellitus (DM), hypertension, elevated aspartate aminotransferase, elevated alanine aminotransferase and elevated triglycerides (TG). In multivariate analysis, factors associated with NAFLD were high body mass index (BMI) (odds ratio [OR] 1.403; 95% confidence interval [CI] 1.111-1.771; p = 0.005), type 2 DM (OR 11.872; 95% CI 1.065-132.373; p = 0.044), and an elevated TG level (OR 50.267; 95% CI 4.409-573.030; p = 0.002).

CONCLUSIONS

The prevalence of NAFLD in breast cancer patients was not different from that of the general population. High BMI, type 2 DM and an elevated serum TG level were factors associated with NAFLD.

Quantitative Imaging Biomarkers of NAFLD

Conventional imaging modalities, including ultrasonography (US), computed tomography (CT), and magnetic resonance (MR), play an important role in the diagnosis and management of patients with nonalcoholic fatty liver disease (NAFLD) by allowing noninvasive diagnosis of hepatic steatosis. However, conventional imaging modalities are limited as biomarkers of NAFLD for various reasons. Multi-parametric quantitative MRI techniques overcome many of the shortcomings of conventional imaging and allow comprehensive and objective evaluation of NAFLD. MRI can provide unconfounded biomarkers of hepatic fat, iron, and fibrosis in a single examination-a virtual biopsy has become a clinical reality. In this article, we will review the utility and limitation of conventional US, CT, and MR imaging for the diagnosis NAFLD. Recent advances in imaging biomarkers of NAFLD are also discussed with an emphasis in multi-parametric quantitative MRI.

Decreased risk of cholangiocarcinogenesis following repeated cycles of Opisthorchis viverrini infection-praziquantel treatment: Magnetic Resonance Imaging (MRI) and histopathological study in a hamster model

It has been suggested that repeated infection of Opisthorchis viverrini followed by repeated treatment with praziquantel (PZQ) increases risk of development of cholangiocarcinoma (CCA). Evidence for the prediction has accumulated based on findings of indirect approaches involving molecular changes and epidemiological trends. By contrast, here we directly monitored the impact of repeated liver fluke infection and treatment with PZQ on cholangiocarcinogenesis in a rodent model of human opisthorchiasis, using magnetic resonance imaging (MRI) and histopathology. Twenty five Syrian golden hamsters were assigned to five treatment groups: 1) infection with O. viverrini (OV group), 2) treatment with the carcinogen N-nitrosodimethylamine (NDMA) at 12.5ppm (DMN), 3) O. viverrini infection in tandem with NDMA (OD), 4) O. viverrini infection, NDMA, and treatment with PZQ (ODP), and 5) uninfected, untreated control. The repeated infections were established by intragastric inoculation of 50 metacercariae of O. viverrini to the OV, OD and ODP hamsters at weeks 0, 5 and 10. PZQ at 300mg/kg body weight was given to each hamster of the ODP group on weeks 4, 9 and 13 (four weeks after each infection). Imaging by MRI was undertaken on weeks 5, 10 and 14 (i.e. one week after each PZQ treatment). MRI revealed that the ODP hamsters did not develop CCA, whereas necropsy at week 40 revealed CCA in hamsters of the OD and DMN groups. Findings for histopathology and for proliferating cell nuclear antigen index conformed to the MRI findings. In overview, and notwithstanding that the immune response of individual hosts may play roles in cholangiocarcinogenesis, three cycles of the infection with O. viverrini followed treatment of the infection with PZQ did not increase the risk of bile duct cancer in this hamster model of liver fluke infection-induced CCA.

Physical Activity Is Prospectively Associated With Adolescent Nonalcoholic Fatty Liver Disease

OBJECTIVES

The aim of the present study was to assess whether objectively measured physical activity at mean ages 12 and 14 years are prospectively associated with ultrasound scan liver fat and stiffness (alanine aminotransferase, aspartate aminotransferase [AST], and γ-glutamyl transferase [GGT]) assessed at mean age 17.8 years.

METHODS

Participants were from the Avon Longitudinal Study of Parents and Children. Total physical activity (counts per minute) and minutes of moderate to vigorous physical activity (MVPA) were measured using ActiGraph accelerometers at mean ages 12 and 14 years.

RESULTS

Greater total physical activity and MVPA at ages 12 and 14 years were associated with lower odds of liver fat and lower GGT levels at mean age 17.8 years, such as per 15-minute increase in daily MVPA at age 12 years, the confounder adjusted odds ratio of liver fat was 0.47 (95% confidence interval [CI] 0.27-0.84). Associations attenuated after additional adjustment for fat mass as a potential confounder (eg, per 15-minute increase in daily MVPA at age 12 years, the odds ratio of liver fat attenuated to 0.65 [95% CI 0.35-1.21]) or a potential mediator (eg, per 15-minute increase in daily MVPA at age 12 years the odds ratio of liver fat attenuated to 0.59 [95% CI 0.32-1.09]). Results did not further attenuate after additional adjustment for insulin resistance. There was some evidence that greater total physical activity and MVPA at age 12 years were associated with the higher AST levels.

CONCLUSIONS

Adolescents who were more active in childhood have lower odds of fatty liver and lower GGT levels. These findings are likely to be, at least in part, explained by adiposity.

The impact of postoperative adjuvant chemotherapy on the development of nonalcoholic fatty liver disease after pancreatoduodenectomy

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) after pancreatoduodenectomy (PD) is increasingly being recognized as a late postoperative complication, but the main causes have not been fully investigated. This study aimed to clarify the relationship between NAFLD after PD and postoperative adjuvant chemotherapy, focusing particularly on the adjuvant chemotherapy regimens administered.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 154 patients who underwent PD from April 2007 to December 2013, to identify the clinicopathologic factors most strongly influencing NAFLD development after PD. Moreover, the postoperative adjuvant chemotherapeutic regimen and the course after the cessation of adjuvant chemotherapy were examined in detail.

RESULTS

The incidence of postoperative NAFLD was 26.6% (41/154). The incidence of NAFLD was significantly higher in the patients with than in those without adjuvant chemotherapy: 38% versus 19% (P = 0.016). Multivariate analysis identified postoperative adjuvant chemotherapy (P = 0.021) and remnant pancreatic volume (P < 0.0001) as independent risk factors. The prevalence of NAFLD after PD was higher in patients treated with the S-1 regimen than in those given either regimens such as those containing gemcitabine or no adjuvant chemotherapy. Recovery from NAFLD 1 y after the cessation of adjuvant chemotherapy was observed in 54.5% (12/22) of patients receiving this treatment. In those treated with the S-1 regimen, improvement was more frequent than in those not receiving adjuvant chemotherapy (57.1% versus 11.8%, P = 0.018).

CONCLUSIONS

Considering the development of NAFLD, adjuvant chemotherapy after PD should be cared for the patients with small remnant pancreas.

Fatty liver formation in fulminant type 1 diabetes

Summary

A 32-year-old woman presented with 3days of epigastric pain and was admitted to our hospital (day 3 of disease). We diagnosed acute pancreatitis based on epigastric abdominal pain, hyperamylasemia, and an inflammatory reaction of withdrawn blood, pancreatic enlargement, and so on. Her condition improved with treatment; however, on day 8, she had decreased level of consciousness. Laboratory results led to a diagnosis of fulminant type 1 diabetes mellitus (FT1DM) with concomitant diabetic ketoacidosis. Insulin therapy improved her blood glucose levels as well as her symptoms. Fatty liver with liver dysfunction was observed on day 14, which improved by day 24. Blood levels of free fatty acids (FFAs) increased rapidly from 440μEq/L (normal range: 140–850μEq/L) on day 4 to 2097μEq/L on days 7–8 (onset of FT1DM) and subsequently decreased to 246μEq/L at the onset of fatty liver. The rapid decrease in insulin at the onset of FT1DM likely freed fatty acids derived from triglycerides in peripheral adipocytes into the bloodstream. Insulin therapy rapidly transferred FFAs from the periphery to the liver. In addition, insulin promotes the de novo synthesis of triglycerides in the liver, using newly acquired FFAs as substrates. At the same time, inhibitory effects of insulin on VLDL secretion outside of the liver promote the accumulation of triglycerides in the liver, leading to fatty liver. We describe the process by which liver dysfunction and severe fatty liver occurs after the onset of FT1DM, from the perspective of disturbed fatty acid metabolism.

Learning Points

FT1DM is rare but should be considered in patients with pancreatitis and a decreased level of consciousness. Fatty liver should be considered in patients with FT1DM when liver dysfunction is observed. Insulin is involved in mechanisms that promote fatty liver formation. Pathophysiological changes in fatty acid metabolism may provide clues on lipid metabolism in the early phases of FT1DM.

Improvement of Nonalcoholic Fatty Liver Disease With Carnitine-Orotate Complex in Type 2 Diabetes (CORONA): A Randomized Controlled Trial

OBJECTIVE

We aimed to evaluate the effects of carnitine-orotate complex in patients with nonalcoholic fatty liver disease (NAFLD) and diabetes.

RESEARCH DESIGN AND METHODS

Eight hospitals in Korea participated in this randomized, controlled, double-blind trial of patients with diabetes and NAFLD. Seventy-eight patients were randomly assigned in a 1:1 ratio to receive carnitine-orotate complex (824 mg, three times daily) or matching placebo. The primary study outcome was decline in alanine aminotransferase (ALT) to the normal range. Secondary study outcomes were change in ALT, radiological hepatic steatosis, parameters for anthropometry, liver function, lipid profiles, and glycemic control. Hepatic steatosis was assessed using Hounsfield units on noncontrast computed tomography (CT) imaging with hepatic attenuation.

RESULTS

After 12 weeks of treatment, compared with placebo group, carnitine-orotate complex-treated participants had a significantly higher rate of normalization of serum ALT level (17.9% vs. 89.7%, P < 0.001). On hepatic CT analysis, participants treated with carnitine-orotate complex showed an increased liver attenuation index (0.74 ± 8.05 vs. 6.21 ± 8.96, P < 0.008). A significant decrease in HbA1c was observed in the carnitine-orotate complex group (-0.33 ± 0.82% [-3.6 ± 9.0 mmol/mol], P = 0.007), but no significant change was seen in the placebo group.

CONCLUSIONS

Treatment with carnitine-orotate complex improves serum ALT and may improve hepatic steatosis as assessed by CT in patients with diabetes and NAFLD. Further studies using more advanced magnetic resonance imaging and liver histology as an end point are needed to assess its efficacy in NAFLD.

MRI and (1)H MRS findings of hepatobilary changes and cholangiocarcinoma development in hamsters infected with Opisthorchis viverrini and treated with N-nitrosodimethylamine

3 T MRI and (1)H MRS were useful for quantitative investigation of the serial development of hepatobiliary changes in Opisthorchis viverrini infection in hamsters, and the differential diagnosis of cholangiocacinoma (CCA) development from bile duct changes and normal condition is unclear. In this study, we investigated the serial development of hepatobiliary changes and CCAgenesis in O. viverrini-infected and N-nitrosodimethylamine (NDMA) treated hamsters (ON group) using 3 T MRI and (1)H MRS and the results were compared with those either in the O. viverrini-infected group (OV group) and uninfected normal controls. In the ON group, CCAs were first found at 9 weeks post-infection, with sizes of ~2 mm. The typical MR signal characteristics of CCA were hypo- and occasionally isointensity signal on T1-weighted images, and mild-moderate to hyper-intensity signal on T2-weighted images compared to the liver parenchyma. T2-weighted images with fat suppression revealed dilatation of the intra- and extrahepatic bile ducts, and often defined the anatomical level of biliary obstruction, cystic lesions, liver abscesses, and CCA which was starting seen of these noticeable abnormalities at 5 weeks onwards. The results of fibrosis grading using MR images showed a positive correlation (r=0.90, P<0.038 by Spearman's rank correlation test) with those of the histopathological grading. In addition, 3.0 T (1)H MRS showed elevated choline and decreased lipids levels in the liver tissues of the ON group. In conclusion, MRI and (1)H MRS are useful for the quantitative investigation of the serial development of hepatobilary changes and CCA in hamsters, and are potentially useful as early diagnostic tools for CCA.

Relation of nonalcoholic fatty liver disease and Framingham Risk Score to flow-mediated dilation in patients with cardiometabolic risk factors

Nonalcoholic fatty liver disease (NAFLD) has a high prevalence in the general population. Brachial artery flow-mediated dilation (FMD) is a surrogated marker of early atherosclerosis. Few data investigating the relation between FMD, NAFLD, and cardiovascular (CV) risk are available. We recruited 367 consecutive outpatients with cardiometabolic risk factors who underwent ultrasound scanning for liver steatosis and FMD. Mean age was 54.2 ± 12.2 years, and 37% were women. NAFLD was present in 281 patients (77%). Median FMD was 5.1%. FMD was significantly reduced in patients with NAFLD (p <0.001), diabetes (p = 0.001), history of coronary heart disease (p = 0.034), and metabolic syndrome (p = 0.050) and in those taking antihypertensive drugs (p = 0.022). Women disclosed greater FMD than males (p = 0.033). Moreover, FMD inversely correlated with age (Spearman rank correlation test [Rs], -0.171; p = 0.001), waist circumference (Rs, -0.127; p = 0.016), fasting blood glucose (Rs, -0.204; p <0.001), and gamma-glutamyl transpeptidase (Rs, -0.064; p = 0.234). At multivariate regression analysis, fasting blood glucose (β, -0.148; p = 0.008), age (β, -0.158; p = 0.005), and the presence of NAFLD (β, -0.132; p = 0.016) inversely correlated with FMD, whereas female gender predicted a better FMD (β, 0.125; p = 0.022). FMD and Framingham Risk Score (FRS) were inversely correlated (Rs, -0.183; p <0.001). After dividing patients into low (FRS <10; FMD, 5.5% [3.1% to 8.9%]), intermediate (FRS 10 to 20; FMD, 4.9% [2.7% to 7.5%]), and high (FRS >20; FMD, 3.3% [1.7% to 4.5%]) risk, FMD significantly decreased across risk classes of FRS (p = 0.003). At multivariate regression analysis, both FRS (β, -0.129; p = 0.016) and NAFLD (β, -0.218; p <0.001) were variables independently associated with FMD. In conclusion, the presence of NAFLD and FRS inversely correlated with FMD.

Childhood energy intake is associated with nonalcoholic fatty liver disease in adolescents

BACKGROUND

Greater adiposity is an important risk factor for nonalcoholic fatty liver disease (NAFLD). Thus, it is likely that dietary intake is involved in the development of the disease. Prospective studies assessing the relation between childhood dietary intake and risk of NAFLD are lacking.

OBJECTIVE

This study was designed to explore associations between energy, carbohydrate, sugar, starch, protein, monounsaturated fat, polyunsaturated fat, saturated fat, and total fat intake by youth at ages 3, 7, and 13 y and subsequent (mean age: 17.8 y) ultrasound scan (USS)-measured liver fat and stiffness and serum alanine aminotransferase, aspartate aminotransferase, and γ-glutamyltransferase. We assessed whether observed associations were mediated through fat mass at the time of outcome assessment.

METHODS

Participants were from the Avon Longitudinal Study of Parents and Children. Trajectories of energy and macronutrient intake from ages 3-13 y were obtained with linear-spline multilevel models. Linear and logistic regression models examined whether energy intake and absolute and energy-adjusted macronutrient intake at ages 3, 7, and 13 y were associated with liver outcomes.

RESULTS

Energy intake at all ages was positively associated with liver outcomes; for example, the odds of having a USS-measured liver fat per 100 kcal increase in energy intake at age 3 y were 1.79 (95% CI: 1.14, 2.79). Associations between absolute macronutrient intake and liver outcomes were inconsistent and attenuated to the null after adjustment for total energy intake. The majority of associations attenuated to the null after adjustment for fat mass at the time liver outcomes were assessed.

CONCLUSION

Higher childhood and early adolescent energy intake is associated with greater NAFLD risk, and the macronutrients from which energy intake is derived are less important. These associations appear to be mediated, at least in part, by fat mass at the time of outcome assessment.

Evidence-based clinical practice guidelines for nonalcoholic fatty liver disease/nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is currently the most common cause of chronic liver disease in industrialized countries worldwide, and has become a serious public health issue not only in Western countries but also in many Asian countries including Japan. Within the wide spectrum of NAFLD, nonalcoholic steatohepatitis (NASH) is a progressive form of disease, which often develops into liver cirrhosis and increases the risk of hepatocellular carcinoma. In turn, a large proportion of NAFLD/NASH is the liver manifestation of metabolic syndrome, suggesting that NAFLD/NASH plays a key role in the pathogenesis of systemic atherosclerotic diseases. Currently, a definite diagnosis of NASH requires liver biopsy, though various noninvasive measures are under development. The mainstays of prevention and treatment of NAFLD/NASH include dietary restriction and exercise; however, pharmacological approaches are often necessary. Currently, vitamin E and thiazolidinedione derivatives are the most evidence-based therapeutic options, although the clinical evidence for long-term efficacy and safety is limited. This practice guideline for NAFLD/NASH, established by the Japanese Society of Gastroenterology in cooperation with The Japan Society of Hepatology, covers lines of clinical evidence reported internationally in the period starting from 1983 to January 2012, and each clinical question was evaluated using the GRADE system. Based on the primary release of the full version in Japanese, this English summary provides the core essentials of this clinical practice guideline comprising the definition, diagnosis, and current therapeutic recommendations for NAFLD/NASH in Japan.

Estimation of normal values of serum transaminases based on liver histology in healthy Asian Indians

BACKGROUND AND AIM

Liver biopsy-based studies have shown that serum levels of aminotransferases are lower than conventional cut-off of 40 IU/mL in persons with normal histology. There is no such study in Indian population based on liver histology. This study aims to estimate normal values of serum aminotransferases in healthy Indian population with normal liver histology.

METHODS

This retrospective study includes all liver donors who underwent liver donation at our centre and had a preoperative liver biopsy done for various reasons. All the donors had negative viral markers. Nonalcoholic fatty liver (NAFL) was defined as > 5% hepatocytes having steatosis and no changes of steatohepatitis.

RESULTS

The study included 331 donors (147 males) with the ages of 35.7 ± 10.2 years. NAFL was present in 167 donors (50.4%). In comparison with male donors with normal histology (n = 67), donors with NAFL (n = 80) had significantly higher age, body mass index, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, gamma-glutamyl transpeptidase, total cholesterol, low-density lipoprotein, and fasting blood sugar. In comparison with female donors with normal histology, donors with NAFL had significantly higher body mass index, ALT, and triglycerides; however, there was no significant difference regarding other parameters. Of the AST and ALT in normal histology donors, 95th percentile were 33.8 IU/L and 38.6 IU/L for males and 31 IU/L and 35.2 IU/L for females. Twenty-five donors had lean NAFL (body mass index < 23 kg/m2).

CONCLUSION

Serum aminotransferase values in healthy Asian Indian population with normal histology are provided. Histological NAFL is present in half of apparently normal donors, and it has different clinical and biochemical associations in males and females.

Evidence-based clinical practice guidelines for nonalcoholic fatty liver disease/nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is currently the most common cause of chronic liver disease in industrialized countries worldwide, and has become a serious public health issue not only in Western countries but also in many Asian countries including Japan. Within the wide spectrum of NAFLD, non-alcoholic steatohepatitis (NASH) is a progressive form of disease, which often develops into liver cirrhosis and increases the risk of hepatocellular carcinoma. In turn, a large proportion of NAFLD/NASH is the liver manifestation of metabolic syndrome, suggesting that NAFLD/NASH plays a key role in the pathogenesis of systemic atherosclerotic diseases. Currently, a definite diagnosis of NASH requires liver biopsy, though various non-invasive measures are under development. The mainstays of prevention and treatment of NAFLD/NASH include dietary restriction and exercise; however, pharmacological approaches are often necessary. Currently, vitamin E and thiazolidinedione derivatives are the most evidence-based therapeutic options, although the clinical evidence for long-term efficacy and safety is limited. This practice guideline for NAFLD/NASH, established by the Japanese Society of Gastroenterology in cooperation with The Japan Society of Hepatology, covers lines of clinical evidence reported internationally in the period starting from 1983 through January 2012, and each clinical question was evaluated using the GRADE system. Based on the primary release of the full version in Japanese, this English summary provides the core essentials of this clinical practice guideline comprising the definition, diagnosis, and current therapeutic recommendations for NAFLD/NASH in Japan.

Weight trajectories through infancy and childhood and risk of non-alcoholic fatty liver disease in adolescence: the ALSPAC study

BACKGROUND & AIMS

Adiposity is a key risk factor for NAFLD. Few studies have examined prospective associations of infant and childhood adiposity with subsequent NAFLD risk. We examined associations of weight-for-height trajectories from birth to age 10 with liver outcomes in adolescence, and assessed the extent to which associations are mediated through fat mass at the time of outcome assessment.

METHODS

Individual trajectories of weight and height were estimated for participants in the Avon Longitudinal Study of Parents and Children using random-effects linear-spline models. Associations of birthweight (adjusted for birth length) and weight change (adjusted for length/height change) from 0-3 months, 3 months-1 y, 1-3 y, 3-7 y, and 7-10 y with ultrasound scan (USS) determined liver fat and stiffness, and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT) at mean age 17.8 y were assessed with linear and logistic regressions. Mediation by concurrent fat mass was assessed with adjustment for fat mass at mean age 17.8 y.

RESULTS

Birth weight was positively associated with liver stiffness and negatively with ALT and AST. Weight change from birth to 1 y was not associated with outcomes. Weight change from 1-3 y, 3-7 y, and 7-10 y was consistently positively associated with USS and blood-based liver outcomes. Adjusting for fat mass at mean age 17.8 y attenuated associations toward the null, suggesting associations are largely mediated by concurrent body fatness.

CONCLUSIONS

Greater rates of weight-for-height change between 1 y and 10 y are consistently associated with adverse liver outcomes in adolescence. These associations are largely mediated through concurrent fatness.

Ultrasonic integrated backscatter in assessing liver steatosis before and after liver transplantation

BACKGROUND

Liver steatosis affects 20%-30% of adults. Because of the increasing gap between graft supplies and demands, livers with steatosis are frequently used in liver transplantation. But severely steatotic liver grafts are associated with a high risk of intraoperative and postoperative complications. Accurate assessment of fat content of donor livers and monitoring of the extent of steatosis in recipients are required for liver transplantation. The present study aimed to determine the correlation between liver echogenicity and fat content, and to evaluate the use of an ultrasonic integrated backscatter system (IBS) in the assessment of changes in fat content after liver transplantation.

METHODS

Seventy-nine consecutive patients receiving liver grafts from living donors were evaluated in our center. Of these recipients, 67 survived for more than two years and were included in this study. Each liver graft was evaluated with IBS and ultrasound before operation and the fat content was estimated. The fat content of the grafts in the recipients was again assessed with ultrasound at 18 months after surgery.

RESULTS

A correlation was detected between each graft's IBS value and its fat content (P=0.001). The IBS value in fatty grafts with various degrees of steatosis was significantly decreased in 3 (P=0.02), 12, 15 and 18 (P=0.001) months after orthotopic liver transplantation. The IBS value returned to normal in all patients in 18 months after liver transplantation.

CONCLUSIONS

Decreased fat content in steatotic grafts can be observed in all recipients. Ultrasonic IBS is useful in determining the steatotic degree of grafts in donors as well as in monitoring the grafts after liver transplantation.