A clinical scoring system for predicting nonalcoholic steatohepatitis in morbidly obese patients

Platelet-derived thrombospondin 1 promotes immune cell liver infiltration and exacerbates diet-induced steatohepatitis

Background & Aims

Recent studies have implicated platelets, particularly α-granules, in the development of non-alcoholic steatohepatitis (NASH). However, the specific mechanisms involved have yet to be determined. Notably, thrombospondin 1 (TSP1) is a major component of the platelet α-granules released during platelet activation. Hence, we aimed to determine the role of platelet-derived TSP1 in NASH.

Methods

Platelet-specific Tsp1 knockout mice (TSP1Δpf4) and their wild-type littermates (TSP1F/F) were used. NASH was induced by feeding the mice with a diet enriched in fat, sucrose, fructose, and cholesterol (AMLN diet). A human liver NASH organoid model was also employed.

Results

Although TSP1 deletion in platelets did not affect diet-induced steatosis, TSP1Δpf4 mice exhibited attenuated NASH and liver fibrosis, accompanied by improvements in plasma glucose and lipid homeostasis. Furthermore, TSP1Δpf4 mice showed reduced intrahepatic platelet accumulation, activation, and chemokine production, correlating with decreased immune cell infiltration into the liver. Consequently, this diminished proinflammatory signaling in the liver, thereby mitigating the progression of NAFLD. Moreover, in vitro data revealed that co-culturing TSP1-deficient platelets in a human liver NASH organoid model attenuated hepatic stellate cell activation and NASH progression. Additionally, TSP1-deficient platelets play a role in regulating brown fat endocrine function, specifically affecting Nrg4 (neuregulin 4) production. Crosstalk between brown fat and the liver may also influence the progression of NAFLD.

Conclusions

These data suggest that platelet α-granule-derived TSP1 is a significant contributor to diet-induced NASH and fibrosis, potentially serving as a new therapeutic target for this severe liver disease.

Impact and implications

Recent studies have implicated platelets, specifically α-granules, in the development of non-alcoholic steatohepatitis, yet the precise mechanisms remain unknown. In this study, through the utilization of a tissue-specific knockout mouse model and human 3D liver organoid, we demonstrated that platelet α-granule-derived TSP1 significantly contributes to diet-induced non-alcoholic steatohepatitis and fibrosis. This contribution is, in part, attributed to the regulation of intrahepatic immune cell infiltration and potential crosstalk between fat and the liver. These findings suggest that platelet-derived TSP1 may represent a novel therapeutic target in non-alcoholic fatty liver disease.

Development and Validation of a Risk Prediction Model for NAFLD: A Study Based on a Physical Examination Population

Purpose

To construct and validate a precise and personalized predictive model for non-alcoholic fatty liver disease (NAFLD) to enhance NAFLD screening and healthcare administration.

Patients and Methods

A total of 730 participants' clinical information and outcome measurements were gathered and randomly divided into training and validation sets in a ratio of 3:7. Using the least absolute shrinkage and selection operator (LASSO) regression and multiple logistic regression, a nomogram was established to select risk predictor variables. The NAFLD prediction model was validated through the receiver operating characteristic (ROC) curve, calibration plot, and decision curve analysis (DCA).

Results

After random grouping, the cohort comprised 517 in the training set and 213 in the validation set. The prediction model employed nine of the 20 selected variables, namely gender, hypertension, waist circumference, body mass index, blood platelet, triglycerides, high-density lipoprotein cholesterol, plasma glucose, and alanine aminotransferase. ROC curve analysis yielded an area under the curve values of 0.877 (95% Confidence Interval [CI]: 0.848-0.907) for the training set and 0.871 (95% CI: 0.825-0.917) for the validation set. Optimal critical values were determined as 0.472 (0.786, 0.825) in the training set and 0.457 (0.743, 0.839) in the validation set. Calibration curves for both sets showed proximity to the ideal diagonal, with P-values of 0.972 and 0.370 for the training and validation sets, respectively (P > 0.05). DCA indicated favorable clinical applicability of the model.

Conclusion

We constructed a nomogram model that could complement traditional NAFLD detection methods, aiding in individualized risk assessment for NAFLD.

Identification and multicentric validation of soluble CDCP1 as a robust serological biomarker for risk stratification of NASH in obese Chinese

The definitive diagnosis of non-alcoholic steatohepatitis (NASH) currently relies on invasive and labor-intensive liver biopsy. Here, we identified soluble CUB domain-containing protein 1 (sCDCP1) as a top-ranked non-invasive biomarker for NASH using Olink-based proteomics in 238 obese individuals with liver biopsies. Both the circulating concentration and hepatic mRNA abundance of sCDCP1 were significantly elevated in patients with NASH and correlated closely with each histological feature of NASH. In the pooled multicenter validation cohort, sCDCP1 as a standalone biomarker achieved an area under the receiver operating characteristic (AUROC) of 0.838 (95% confidence interval [CI] 0.789-0.887) for diagnosing NASH, which is better than those achieved with cytokeratin-18 and other non-invasive tests. Furthermore, the C-DAG model established by the combination of sCDCP1 with diabetes, aspartate aminotransferase (AST), and gender accurately rules in and rules out both NASH and fibrotic NASH (gray zones <20%). Thus, sCDCP1-based non-invasive tests can be potentially implemented for screening and early diagnosis of NASH and for ruling out low-risk individuals to avoid unnecessary liver biopsies.

Thyroid hormone Beta receptor agonists for treatment of kidney disease: A promising agent?

BACKGROUND

Chronic kidney disease is a common disorder affecting a significant portion of the adult population with high mortality and morbidity. Obesity and hyperlipidemia are prevalent in chronic kidney disease, and they may trigger fat accumulation in renal parenchyma and eventually fatty kidney. Chronic kidney disease and fatty kidney are also strongly associated with nonalcoholic fatty liver disease. Because they both lead to detrimental effects on organ function, they both need to be treated effectively to improve the outcome.

AIM

In this narrative review, we have hypothesized that thyroid hormone beta receptor agonists, a novel drug group, may potentially be beneficial in the management of chronic kidney disease due to its promising outcomes among patients with nonalcoholic fatty liver disease, a condition sharing multiple common underlying pathophysiological mechanisms.

RESULTS AND CONCLUSION

Thyroid hormone beta receptors are abundantly expressed in liver and kidney tissues, while both nonalcoholic fatty liver disease and chronic kidney disease share various similar pathophysiological mechanisms and triggers. Therefore, thyroid hormone beta receptor agonists may become a promising tool in the management of patients with chronic kidney disease.

[State of the art on the pathophysiology, diagnosis and treatment of non-alcoholic steatohepatitis (NASH)]

NAFLD or non-alcoholic fatty liver disease is one of the complications of obesity and diabetes, the prevalence of which is increasing. The causes of the pathology and its development towards its severe form, NASH or non-alcoholic steatohepatitis, are multiple and still poorly understood. Many different pharmacological classes are being tested in clinical trials to treat NASH, but no pharmaceutical treatment is currently on the market. Moreover, the diagnosis of certainty is only possible by liver biopsy and histological analysis, an invasive procedure with high risk for the patient. It is therefore necessary to better understand the natural history of the disease in order to identify therapeutic targets, but also to identify markers for the diagnosis and monitoring of the disease using a blood sample, which will allow an improvement in patient management.

Stellate cell expression of SPARC-related modular calcium-binding protein 2 is associated with human non-alcoholic fatty liver disease severity

Background & Aims

Histological assessment of liver biopsies is the gold standard for diagnosis of non-alcoholic steatohepatitis (NASH), the progressive form of non-alcoholic fatty liver disease (NAFLD), despite its well-established limitations. Therefore, non-invasive biomarkers that can offer an integrated view of the liver are needed to improve diagnosis and reduce sampling bias. Hepatic stellate cells (HSCs) are central in the development of hepatic fibrosis, a hallmark of NASH. Secreted HSC-specific proteins may, therefore, reflect disease state in the NASH liver and serve as non-invasive diagnostic biomarkers.

Methods

We performed RNA-sequencing on liver biopsies from a histologically characterised cohort of obese patients (n = 30, BMI >35 kg/m²) to identify and evaluate HSC-specific genes encoding secreted proteins. Bioinformatics was used to identify potential biomarkers and their expression at single-cell resolution. We validated our findings using single-molecule fluorescence in situ hybridisation (smFISH) and ELISA to detect mRNA in liver tissue and protein levels in plasma, respectively.

Results

Hepatic expression of SPARC-related modular calcium-binding protein 2 (SMOC2) was increased in NASH compared to no-NAFLD (p.adj <0.001). Single-cell RNA-sequencing data indicated that SMOC2 was primarily expressed by HSCs, which was validated using smFISH. Finally, plasma SMOC2 was elevated in NASH compared to no-NAFLD (p <0.001), with a predictive accuracy of AUROC 0.88.

Conclusions

Increased SMOC2 in plasma appears to reflect HSC activation, a key cellular event associated with NASH progression, and may serve as a non-invasive biomarker of NASH.

Impact and implications

Non-alcoholic fatty liver disease (NAFLD) and its progressive form, non-alcoholic steatohepatitis (NASH), are the most common forms of chronic liver diseases. Currently, liver biopsies are the gold standard for diagnosing NAFLD. Blood-based biomarkers to complement liver biopsies for diagnosis of NAFLD are required. We found that activated hepatic stellate cells, a cell type central to NAFLD pathogenesis, upregulate expression of the secreted protein SPARC-related modular calcium-binding protein 2 (SMOC2). SMOC2 was elevated in blood samples from patients with NASH and may hold promise as a blood-based biomarker for the diagnosis of NAFLD.

A diagnostic proposal for sarcopenic obesity in adults based on body composition phenotypes

BACKGROUND & AIMS

Sarcopenic obesity (SO) associates a decrease in lean body mass (LBM) with an excessive increase in fat mass (FM). A number of diagnostic methods, definitions criteria, and thresholds have been proposed for SO resulting in markedly discordant prevalence estimates in populations with obesity. In this study, we first assessed several previously described SO diagnostic criteria and their limitations, and then we propose an innovative approach for identifying SO.

METHODS

Data were from a cross-sectional study of a cohort of overweight/obese patients who underwent clinical, laboratory, and body composition assessments by dual-energy X-ray absorptiometry (DXA). We performed unsupervised machine learning through clustering analysis to discriminate lean and fat compartments, and multivariate logistic regressions which provided prognostic variables applied on sex-specific models for SO diagnosis evaluation based on a training dataset (80% of total sample, n = 1165). The predicted models were validated by random forest (RF) machine learning algorithm in the validation dataset (20% of total sample, n = 262).

RESULTS

Data from 1427 subjects were analyzed, 79.8% women, mean (±s.d.) age 45.0 (±12.9) years, grade III obesity (BMI over 40 kg/m²) in 42.7%, diabetes in 20.7%, dyslipidemia in 86.3%, and arterial hypertension in 30.3%. Patients with grade III obesity had higher amounts of LBM, FM, and bone mass than subjects with overweight (BMI between 25.0 and 29.9 kg/m²) (p-values < 0.001). When published definitions of SO were applied to this cohort, the prevalence ranged from 0.6% to 96.6%. We built a model that identified 62 (4.3%) individuals as SO, 1125 (78.9%) as non-SO, and 240 (16.8%) as borderline-SO. SO patients showed higher body weight, FM, bone mass, leptin levels, and hepatic steatosis index, but lower LBM and all muscle indexes than non-SO subjects (p-values ≤ 0.001). Patients in the SO and borderline-SO categories were more often females than males (4.5% vs. 3.8% and 16.9% vs. 16.7% respectively, p-value < 0.001) and had significantly higher prevalence of metabolic syndrome and hypertension than non-SO subjects. Males with SO also had higher cardiovascular risk score, while females had higher prevalence of respiratory disorders (p-values < 0.05 for all).

CONCLUSIONS

Current diagnostic criteria for SO result in widely discrepant prevalence values leading to diagnosis uncertainty. We developed and validated diagnostic criteria based on body composition phenotypes, specifically for overweight/obese subjects, which identified patients at risk of cardio-metabolic complications. This approach may improve the identification of sarcopenia in subjects with obesity.

Factors Predicting the Development of Necrosis in Patients Presenting With Edematous Acute Pancreatitis

OBJECTIVES

There is no marker that can accurately predict the development of pancreatic necrosis in edematous acute pancreatitis (AP). This study aimed to investigate the factors associated with necrosis development in cases of edematous AP and to create an easy-to-use scoring system.

METHODS

We retrospectively reviewed patients diagnosed with edematous AP between 2010 and 2021. Among the patients, those who were found to have developed necrosis during follow-up were categorized as the necrotizing group, whereas the others constituted the edematous group.

RESULTS

With multivariate analysis, white blood cell, hematocrit, lactate dehydrogenase, and C-reactive protein levels at the 48th hour were revealed to be independent risk factors for necrosis. Using these 4 independent predictors, the Necrosis Development Score 48 (NDS-48) was derived. While the cutoff value was 2.5, the sensitivity and specificity of the NDS-48 for necrosis were 92.5% and 85.9%, respectively. The area under the curve value of the NDS-48 for necrosis was 0.949 (95% confidence interval, 0.920-0.977).

CONCLUSIONS

White blood cell, hematocrit, lactate dehydrogenase, and C-reactive protein levels at the 48th hour are independent predictors of necrosis development. The NDS-48, a new scoring system created with these 4 predictors, satisfactorily predicted the development of necrosis.

A liver secretome gene signature-based approach for determining circulating biomarkers of NAFLD severity

Non-invasive biomarkers of non-alcoholic fatty liver disease (NAFLD) supporting diagnosis and monitoring disease progression are urgently needed. The present study aimed to establish a bioinformatics pipeline capable of defining and validating NAFLD biomarker candidates based on paired hepatic global gene expression and plasma bioanalysis from individuals representing different stages of histologically confirmed NAFLD (no/mild, moderate, more advanced NAFLD). Liver secretome gene signatures were generated in a patient cohort of 26 severely obese individuals with the majority having no or mild fibrosis. To this end, global gene expression changes were compared between individuals with no/mild NAFLD and moderate/advanced NAFLD with subsequent filtering for candidate gene products with liver-selective expression and secretion. Four candidate genes, including LPA (lipoprotein A), IGFBP-1 (insulin-like growth factor-binding protein 1), SERPINF2 (serpin family F member 2) and MAT1A (methionine adenosyltransferase 1A), were differentially expressed in moderate/advanced NAFLD, which was confirmed in three independent RNA sequencing datasets from large, publicly available NAFLD studies. The corresponding gene products were quantified in plasma samples but could not discriminate among different grades of NAFLD based on NAFLD activity score. Conclusion: We demonstrate a novel approach based on the liver transcriptome allowing for identification of secreted hepatic gene products as potential circulating diagnostic biomarkers of NAFLD. Using this approach in larger NAFLD patient cohorts may yield potential circulating biomarkers for NAFLD severity.

Prevalence and predictors of non-alcoholic steatohepatitis in subjects with morbid obesity and with or without type 2 diabetes

AIM

To investigate the prevalence of biopsy-proven non-alcoholic steatohepatitis (NASH) in a cohort of patients with morbid obesity and with or without type 2 diabetes (T2D) and to find non-invasive predictors of NASH severity.

METHODS

We evaluated a cohort of 412 subjects (age 19-67 years, body mass index-BMI: 44.98 kg/m²), who underwent fine-needle liver biopsy during bariatric surgery. Thirty-six percent of the subjects were affected by T2D. Liver biopsies were classified according to the Kleiner's NAFLD Activity Score (NAS). NAFLD Fibrosis Score (NFS), AST/ALT ratio, AST to Platelet ratio (APRI), fibrosis-4 score (FIB4) were calculated. A neural network analysis (NNA) was run to predict NASH severity.

RESULTS

The prevalence of biopsy-proven NASH was 63% and 78% in subjects with obesity and without or with T2D, respectively. T2D doubled the risk of NASH [OR 2.079 (95% IC=1.31-3.29)]. The prevalence of NAFL increased with the increase of BMI, while there was an inverse correlation between BMI and NASH (r=-0.145 p=0.003). Only mild liver fibrosis was observed. HOMA-IR was positively associated with hepatocyte ballooning (r=0.208, p<0.0001) and fibrosis (r=0.159, p=0.008). The NNA highlighted a specificity of 77.3% using HDL-cholesterol, BMI, and HOMA-IR as main determinants of NASH.

CONCLUSIONS

Our data show a higher prevalence of NASH in patients with morbid obesity than reported in the literature and the pivotal role of T2D among the risk factors for NASH development. However, the inverse correlation observed between BMI and biopsy-proven NASH suggests that over a certain threshold adiposity can be somewhat protective against liver damage. Our model predicts NASH presence with high specificity, thus helping identifying subjects who should promptly undergo liver biopsy.

Hepatic Steatosis Is Associated with High White Blood Cell and Platelet Counts

The incidence of hepatic steatosis is increasing globally, and it is important to identify those at risk to prevent comorbidities. Complete blood count is a simple, convenient, and inexpensive laboratory examination which can be used to obtain white blood cell (WBC) and platelet counts. The aims of this study were to investigate the relationships between WBC and platelet counts with hepatic steatosis, and whether WBC and platelet counts were associated with the severity of hepatic steatosis. We enrolled 1969 participants residing in southern Taiwan who took part in a health survey from June 2016 to September 2018 in this cross-sectional study. None of the participants were heavy alcohol users or had a history of hepatitis B or C. We collected laboratory data, and the severity of hepatic steatosis was determined by abdominal ultrasound. The overall prevalence rate of hepatic steatosis was 42.0%. There were significant trends of stepwise increases in WBC count (p < 0.001) corresponding to the severity of hepatic steatosis. After multivariable linear regression analysis, hepatic steatosis was significantly associated with high WBC count (coefficient β, 0.209; 95% confidence interval (CI), 0.055 to 0.364; p = 0.008) and high platelet count (coefficient β, 12.213; 95% CI, 6.092 to 18.334; p < 0.001); also, higher WBC counts corresponded with the severity of hepatic steatosis.

Prevalence and predictors of non-alcoholic steatohepatitis in patients with morbid obesity

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is highly prevalent in morbid obesity (MO). A considerable proportion of patients with MO have non-alcoholic steatohepatitis (NASH). Liver biopsy (LB) is the only procedure that reliably differentiates NASH from other stages of NAFLD, but its invasive nature prevents it from being generalisable. Hence, non-invasive assessment is critical in this group of patients.

OBJECTIVES

To report NAFLD/NASH prevalence in a cohort of patients with MO and to identify predictors of NASH.

METHODS

Fifty-two consecutive patients subjected to bariatric surgery in a University hospital in Spain underwent LB. Anthropometric, clinical and biochemical variables were registered. According of the results of the LB, individuals were classified by whether they had NASH or not. Multiple logistic regression analysis was performed to identify independent factors associated with NASH.

RESULTS

NAFLD was reported in 94.2% of the patients, simple steatosis was present in 51.92% and NASH in 42.31%. Meanwhile, 17.3% of patients exhibited significant fibrosis (≥F2). HIGHT score for NASH risk was established using five independent predictors: systemic Hypertension, Insulin resistance, Gamma-glutamyl transferase, High density lipoprotein cholesterol and alanine Transaminase. This score ranges from 0 to 7 and was used to predict NASH in our cohort (area under the receiver operator characteristic curve 0.846). A score of 4 or greater implied high risk (sensitivity 77.3%, specificity 73.3%, positive predictive value 68%, negative predictive value 81.5%, accuracy 75%).

CONCLUSIONS

NAFLD is practically a constant in MO with a considerable proportion of patients presenting NASH. The combination of five independent predictors in a scoring system may help the clinician optimise the selection of patients with MO for LB.

FAT score: an Indian insight to a novel diagnostic score to differentiate non-alcoholic steatohepatitis (NASH) from simple steatosis

Background

The aim of this study was to propose a simple predictive score to differentiate NASH from simple steatosis.

Results

This study included 64 patients who had biopsy-proven NAFLD, of which 34 patients had steatohepatitis and 30 had simple steatosis. Clinical, anthropometric, and biochemical variables of the study population were analyzed. Univariate analysis showed platelet count, ferritin, and transaminases (ALT&AST) were predictors of NASH. This led to the proposal of a new diagnostic tool, FAT score (F signifies Ferritin, A indicates AST&ALT, T denotes t in Platelet) with AUROC of 0.95. The ROC curves for the significant variables were plotted and cutoff values were identified. Each component is awarded a score of 0 or 1, based on this cutoff value. The component is awarded a score of 1 if the component score is above the cutoff value and 0, if the score is below cutoff. The maximum score which can be obtained is 4. A score of ≥ 3 was able to predict NASH from simple steatosis with a sensitivity of 76.5% and a specificity of 100%. The score was validated with a cohort of 84 liver biopsy patients wherein a cutoff ≥ 3 was found to give a specificity of 100% in the validation cohort.

Conclusions

FAT score is a simple predictive model to differentiate NASH from simple steatosis (cutoff of more than or equal to 3) without performing a liver biopsy. A FAT score less than 3 rules out the need for biopsy.

Expert opinion on the preoperative medical optimization of adults with diabetes undergoing metabolic surgery

Diabetes mellitus (DM) and obesity are interrelated in a complex manner, and their coexistence predisposes patients to a plethora of medical problems. Metabolic surgery has evolved as a promising therapeutic option for both conditions. It is recommended that patients, particularly those of Asian origin, maintain a lower body mass index threshold in the presence of uncontrolled DM. However, several comorbidities often accompany these chronic diseases and need to be addressed for successful surgical outcome. Laparoscopic Roux-en-Y gastric bypass (RYGB) and laparoscopic sleeve gastrectomy (LSG) are the most commonly used bariatric procedures worldwide. The bariatric benefits of RYGB and LSG are similar, but emerging evidence indicates that RYGB is more effective than LSG in improving glycemic control and induces higher rates of long-term DM remission. Several scoring systems have been formulated that are utilized to predict the chances of remission. A glycemic target of glycated hemoglobin < 7% is a reasonable goal before surgery. Cardiovascular, pulmonary, gastrointestinal, hepatic, renal, endocrine, nutritional, and psychological optimization of surgical candidates improves perioperative and long-term outcomes. Various guidelines for preoperative care of individuals with obesity have been formulated, but very few specifically focus on the concerns arising from the presence of concomitant DM. It is hoped that this statement will lead to the standardization of presurgical management of individuals with DM undergoing metabolic surgery.

Multidimensional Biomarker Analysis Including Mitochondrial Stress Indicators for Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is accompanied by a complex and multifactorial pathogenesis with sequential progressions from inflammation to fibrosis and then to cancer. This heterogeneity interferes with the development of precise diagnostic and prognostic strategies for NAFLD. The current approach for the diagnosis of simple steatosis, steatohepatitis, and cirrhosis mainly consists of ultrasonography, magnetic resonance imaging, elastography, and various serological analyses. However, individual dry and wet biomarkers have limitations demanding an integrative approach for the assessment of disease progression. Here, we review diagnostic strategies for simple steatosis, steatohepatitis and hepatic fibrosis, followed by potential biomarkers associated with fat accumulation and mitochondrial stress. For mitochondrial stress indicators, we focused on fibroblast growth factor 21 (FGF21), growth differentiation factor 15 (GDF15), angiopoietin-related growth factor and mitochondrial-derived peptides. Each biomarker may not strongly indicate the severity of steatosis or steatohepatitis. Instead, multidimensional analysis of different groups of biomarkers based on pathogenic mechanisms may provide decisive diagnostic/prognostic information to develop a therapeutic plan for patients with NAFLD. For this purpose, mitochondrial stress indicators, such as FGF21 or GDF15, could be an important component in the multiplexed and contextual interpretation of NAFLD. Further validation of the integrative evaluation of mitochondrial stress indicators combined with other biomarkers is needed in the diagnosis/prognosis of NAFLD.

Prevalence and predictors of non-alcoholic steatohepatitis in patients with morbid obesity

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is highly prevalent in morbid obesity (MO). A considerable proportion of patients with MO have non-alcoholic steatohepatitis (NASH). Liver biopsy (LB) is the only procedure that reliably differentiates NASH from other stages of NAFLD, but its invasive nature prevents it from being generalisable. Hence, non-invasive assessment is critical in this group of patients.

OBJECTIVES

To report NAFLD/NASH prevalence in a cohort of patients with MO and to identify predictors of NASH.

METHODS

Fifty-two consecutive patients subjected to bariatric surgery in a University hospital in Spain underwent LB. Anthropometric, clinical and biochemical variables were registered. According of the results of the LB, individuals were classified by whether they had NASH or not. Multiple logistic regression analysis was performed to identify independent factors associated with NASH.

RESULTS

NAFLD was reported in 94.2% of the patients, simple steatosis was present in 51.92% and NASH in 42.31%. Meanwhile, 17.3% of patients exhibited significant fibrosis (≥F2). HIGHT score for NASH risk was established using five independent predictors: systemic Hypertension, Insulin resistance, Gamma-glutamyl transferase, High density lipoprotein cholesterol and alanine Transaminase. This score ranges from 0 to 7 and was used to predict NASH in our cohort (area under the receiver operator characteristic curve 0.846). A score of 4 or greater implied high risk (sensitivity 77.3%, specificity 73.3%, positive predictive value 68%, negative predictive value 81.5%, accuracy 75%).

CONCLUSIONS

NAFLD is practically a constant in MO with a considerable proportion of patients presenting NASH. The combination of five independent predictors in a scoring system may help the clinician optimise the selection of patients with MO for LB.

Non-alcoholic fatty liver and chronic kidney disease: Retrospect, introspect, and prospect

With the growing prevalence of obesity and diabetes in the United States and across the world, a rise in the overall incidence and prevalence of non-alcoholic fatty liver disease (NAFLD) is expected. The risk factors for NAFLD are also associated with the development of chronic kidney disease (CKD). We review the epidemiology, risk factors, genetics, implications of gut dysbiosis, and specific pathogenic mechanisms linking NAFLD to CKD. Mechanisms such as ectopic lipid accumulation, cellular signaling abnormalities, and the interplay between fructose consumption and uric acid accumulation have led to the emergence of potential therapeutic implications for this patient population. Transplant evaluation in the setting of both NAFLD and CKD is also reviewed. Potential strategies for surveillance and management include the monitoring of comorbidities, the use of non-invasive fibrosis scoring systems, and the measurement of laboratory markers. Lastly, we discuss the management of patients with NAFLD and CKD, from preventative measures to experimental interventions.

Utility of Multiparametric CT for Identification of High-Risk NAFLD

OBJECTIVE. The purpose of this study was to evaluate the utility of laboratory and CT metrics in identifying patients with high-risk nonalcoholic fatty liver disease (NAFLD). MATERIALS AND METHODS. Patients with biopsy-proven NAFLD who underwent CT within 1 year of biopsy were included. Histopathologic review was performed by an experienced gastrointestinal pathologist to determine steatosis, inflammation, and fibrosis. The presence of any lobular inflammation and hepatocyte ballooning was categorized as nonalcoholic steatohepatitis (NASH). Patients with NAFLD and advanced fibrosis (stage F3 or higher) were categorized as having high-risk NAFLD. Aspartate transaminase to platelet ratio index and Fibrosis-4 (FIB-4) laboratory scores were calculated. CT metrics included hepatic attenuation, liver segmental volume ratio (LSVR), splenic volume, liver surface nodularity score, and selected texture features. In addition, two readers subjectively assessed the presence of NASH (present or not present) and fibrosis (stages F0-F4). RESULTS. A total of 186 patients with NAFLD (mean age, 49 years; 74 men and 112 women) were included. Of these, 87 (47%) had NASH and 112 (60%) had moderate to severe steatosis. A total of 51 patients were classified as fibrosis stage F0, 42 as F1, 23 as F2, 37 as F3, and 33 as F4. Additionally, 70 (38%) had advanced fibrosis (stage F3 or F4) and were considered to have high-risk NAFLD. FIB-4 score correlated with fibrosis (ROC AUC of 0.75 for identifying high-risk NAFLD). Of the individual CT parameters, LSVR and splenic volume performed best (AUC of 0.69 for both for detecting high-risk NAFLD). Subjective reader assessment performed best among all parameters (AUCs of 0.78 for reader 1 and 0.79 for reader 2 for detecting high-risk NAFLD). FIB-4 and subjective scores were complementary (combined AUC of 0.82 for detecting high-risk NAFLD). For NASH assessment, FIB-4 performed best (AUC of 0.68), whereas the AUCs were less than 0.60 for all individual CT features and subjective assessments. CONCLUSION. FIB-4 and multiple CT findings can identify patients with high-risk NAFLD (advanced fibrosis or cirrhosis). However, the presence of NASH is elusive on CT.

Development and Validation of a Novel Scoring System for Noninvasive Nonalcoholic Steatohepatitis Detection in Bariatric Patients

INTRODUCTION

Nonalcoholic fatty liver disease covers a broad spectrum. Simple steatosis has usually a benign course while nonalcoholic steatohepatitis (NASH) can progress into hepatocellular carcinoma, and cirrhosis. Therefore, differentiating patients with benign steatosis and NASH is crucial. Liver biopsy, the usual gold standard for NASH diagnosis, cannot be used as a screening method due to its associated risks. This is especially problematic for obese patients with a prevalence of nonalcoholic fatty liver disease (NAFLD) in >80% of patients. The aim of this study was therefore to develop and validate a noninvasive NASH screening test in a cohort of high-risk, morbidly obese patients.

METHODS

This prospective study examined diagnostic accuracy in accordance with STARD guidelines. 112 liver biopsies were consecutively assigned to either a training or validation cohort. Using the Bedossa histological scoring system, the cohorts were subdivided into NASH versus NAFLD/No NAFLD. Predictors of NASH were evaluated with receiver operating characteristic (ROC) curves. A model was then constructed using a backward stepwise logistic regression and evaluated in an independent validation cohort.

RESULTS

53.5% of the patients had NASH and 4 patients had cirrhosis. Mean body mass index (BMI) was 49.8 ± 7.5 kg/m2. Backward stepwise logistic regression identified 4 parameters associated with the presence of NASH: alanin-aminotransferase, albumin, BMI, and triglycerides. The noninvasive NASH detection score (NI-NASH-DS) had an ROC of 0.851 and 0.727 in the training and validation cohorts, respectively. Sensitivity and specificity were 77.1% and 88% in the training cohort and 88% and 48% in the validation cohort which was much better than the established noninvasive scores.

DISCUSSION/CONCLUSION

The NI-NASH-DS is easy-to-use, inexpensive, and noninvasive and can reliably detect NASH in patients with morbid obesity. Due to its simplicity, it can be used frequently and repeatedly.

Sleep disorder in patients with chronic liver disease: a narrative review

Sleep disturbance is a common feature of chronic liver disease (CLD) with impact on health-related quality of life; 60-80% of patients with CLD report subjective poor sleep; frequent presentations of sleep disturbance include insomnia, reduced sleep efficiency, increased sleep latency, reduced time in rapid eye movement (REM) sleep, restless leg syndrome and excessive daytime sleepiness (EDS). Key contributors to sleep disturbance include hepatic encephalopathy (HE) and circadian rhythm imbalance due to altered melatonin metabolism. Specific conditions causing CLD, such as non-alcoholic fatty liver disease (NAFLD), chronic viral hepatitis and primary biliary cholangitis (PBC) result in different types of sleep disturbance, and the treatment of these conditions can often also lead to sleep disturbance. There are currently limited management options for sleep disturbance in CLD. Obstructive sleep apnoea (OSA) is a common condition that causes chronic intermittent hypoxia due to airway collapse during sleep. This chronic intermittent hypoxia appears to contribute to the development of NAFLD. The presence of reactive oxygen species and the overexpression of hypoxia inducible factor 1-alpha secondary to hypoxia may be responsible for the second 'hit' of the 'two-hit' hypothesis of NAFLD. Treatment of the intermittent hypoxia with continuous positive airway pressure therapy has limited efficacy against liver dysfunction. There remain many outstanding areas of investigation in the management of sleep disturbance in CLD, and of liver dysfunction in OSA.

The diagnostic conundrum in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) has become the most common liver alteration worldwide. It encompasses a spectrum of disorders that range from simple steatosis to a progressive form, defined non-alcoholic steatohepatitis (NASH), that can lead to advanced fibrosis and eventually cirrhosis and hepatocellular carcinoma. On liver histology, NASH is characterized by the concomitant presence of significant fat accumulation and inflammatory reaction with hepatocellular injury. Until now, liver biopsy is still required to differentiate simple steatosis from NASH and evaluate the degree of liver fibrosis. Unfortunately, this technique has well-known limitations, including invasiveness and expensiveness. Moreover, it may be biased by sampling error and intra- or inter-observed variability. Furthermore, due to the increasing prevalence of NAFLD worldwide, to program a systematic screening with liver biopsy is not imaginable. In recent years, different techniques were developed and validated with the aim of non-invasively identifying NASH and assess liver fibrosis degrees. The non-invasive tests range from simple blood-tests analyses to composite scores and complex imaging techniques. Nevertheless, even if they could represent cost-effective strategies for diagnosing NASH, advanced fibrosis and cirrhosis, their accuracy and consequent usefulness are to be discussed. With this aim, in this review the authors summarize the current state of non-invasive assessment of NAFLD. In particular, in addition to the well-established tests, the authors describe the future perspectives in this field, reporting the latest tests based on OMICS, gut-miocrobioma and micro-RNAs. Finally, the authors provide an accurate assessment of how these non-invasive tools perform in clinical practice depending on the clinical context, with the aim of giving the clinicians a useful tool to try to resolve the diagnostic conundrum of NAFLD.

Evaluation of NAFLD and fibrosis in obese patients - a comparison of histological and clinical scoring systems

Background

Non-alcoholic fatty liver disease (NAFLD) is a frequent condition in obese patients and regularly progresses to non-alcoholic steatohepatitis (NASH) and subsequent cirrhosis. Histologic evaluation is the gold standard for grading and staging, but invasive biopsies are associated with obvious risks. The aim of this study was to evaluate different non-invasive tools for screening of NAFLD and fibrosis in obese patients.

Methods

In a prospective cohort study liver specimens of 141 patients were taken during bariatric surgery. Serological parameters and clinical data were collected and the following scores calculated: NASH clinical scoring system (NCS), aspartate aminotransferase to platelet ratio index (APRI), FIB-4 as well as NAFLD fibrosis score (NFS). Liver function capacity was measured preoperatively by LiMAx test (enzymatic capacity of cytochrome P450 1A2). Intraoperative liver biopsies were classified using NAFLD activity score (NAS) and steatosis, activity and fibrosis (SAF) score.

Results

APRI was able to differentiate between not NASH and definite NASH with a sensitivity of 74% and specificity of 67% (AUROC 0.76). LiMAx and NCS also showed significant differences between not NASH and definite NASH. No significant differences were found for NFS and Fib-4. APRI had a high sensitivity (83%) and specificity (76%) in distinguishing fibrosis from no fibrosis (AUROC = 0.81). NCS and Fib-4 also revealed high AUROCs (0.85 and 0.67), whereas LiMAx and NFS did not show statistically significant differences between fibrosis stages. Out of the patients with borderline NASH in the histologic NAS score, 48% were classified as NASH by SAF score.

Conclusions

APRI allows screening of NAFLD as well as fibrosis in obese patients. This score is easy to calculate and affordable, while conveniently only using routine clinical parameters. Using the NAS histologic scoring system bears the risk of underdiagnosing NASH in comparison to SAF score.

Insulin sensitizer MSDC-0602K in non-alcoholic steatohepatitis: A randomized, double-blind, placebo-controlled phase IIb study

BACKGROUND & AIMS

MSDC-0602K is a novel insulin sensitizer designed to preferentially target the mitochondrial pyruvate carrier while minimizing direct binding to the transcriptional factor PPARγ. Herein, we aimed to assess the efficacy and safety of MSDC-0602K in patients with non-alcoholic steatohepatitis.

METHODS

Patients with biopsy-confirmed NASH and fibrosis (F1-F3) were randomized to daily oral placebo, or 1 of 3 MSDC-0602K doses in a 52-week double-blind study. The primary efficacy endpoint was hepatic histological improvement of ≥2 points in non-alcoholic fatty liver disease activity score (NAS) with a ≥1-point reduction in either ballooning or lobular inflammation and no increase in fibrosis stage at 12 months. Secondary endpoints included NAS improvement without worsening fibrosis, NASH resolution, and fibrosis reduction. Exploratory endpoints included changes in insulin sensitivity, liver injury and liver fibrosis markers.

RESULTS

Patients were randomly assigned to placebo (n = 94), or 62.5 mg (n = 99), 125 mg (n = 98), or 250 mg (n = 101) of MSDC-0602K. At baseline, glycated hemoglobin was 6.4 ± 1.0%, 61.5% of patients had fibrosis F2/F3 and the average NAS was 5.3. The primary endpoint was reached in 29.7%, 29.8%, 32.9% and 39.5% of patients in the placebo, 62.5 mg, 125 mg and 250 mg dose arms, respectively, with adjusted odds ratios relative to placebo of 0.89 (95% CI 0.44-1.81), 1.22 (95% CI 0.60-2.48), and 1.64 (95% CI 0.83-3.27). The 2 highest doses of MSDC-0602K led to significant reductions in glucose, glycated hemoglobin, insulin, liver enzymes and NAS compared to placebo. The incidence of hypoglycemia and PPARγ-agonist-associated events such as edema and fractures were similar in the placebo and MSDC-0602K groups.

CONCLUSIONS

MSDC-0602K did not demonstrate statistically significant effects on primary and secondary liver histology endpoints. However, effects on non-invasive measures of liver cell injury and glucose metabolism support further exploration of MSDC-0602K's safety and potential efficacy in patients with type 2 diabetes and liver injury. [ClinicalTrials.gov Identifier: NCT02784444].

LAY SUMMARY

First-generation insulin sensitizers are used to treat type 2 diabetes, but are associated with side effects including edema, bone fractures, and hypoglycemia. MSDC-0602K is a second-generation insulin sensitizer designed to reduce these side effects. We hypothesized that insulin sensitization could improve non-alcoholic steatohepatitis. In the current study of patients with non-alcoholic steatohepatitis, MSDC-0602K did not demonstrate significant effects on liver histology with the biopsy techniques used. However, useful information was gained for the design of future studies and MSDC-0602K significantly decreased fasting glucose, insulin, glycated hemoglobin, and markers of liver injury without dose-limiting side effects.

Differentiation between stages of non-alcoholic fatty liver diseases using surface-enhanced Raman spectroscopy

Non-alcoholic fatty liver disease (NAFLD) is a chronic disorder progressing from an initial benign accumulation of fat (NAFL) towards steatohepatitis (NASH), a degenerative form that can lead to liver cirrhosis and cancer. The development of non-invasive, rapid and accurate method to diagnose NASH is of high clinical relevance. Surface-enhanced Raman spectroscopy (SERS) of plasma was tested as a method to distinguish NAFL from NASH. SERS spectra from plasma of female patients diagnosed with NAFL (n = 32) and NASH (n = 35) were obtained in few seconds, using a portable Raman spectrometer. The sample consisted of 5 μL of biofluid deposited on paper coated with Ag nanoparticles. The spectra show consistent differences between the NAFL and NASH patients, with the uric acid/hypoxanthine band area ratio statistically different (p-value <0.001) between the two groups. The average figures of merit for a diagnostic test based on these ratios, as derived from a repeated 4-fold cross-validation of a logistic regression model, are all between 0.73 and 0.79, with an average area under the curve of 0.81. We conclude that SERS may be a reliable and rapid method to discriminate NAFLD from NASH.

Obstructive Sleep Apnea, Hypoxia, and Nonalcoholic Fatty Liver Disease

Recent studies have demonstrated that obstructive sleep apnea (OSA) is associated with the development and evolution of nonalcoholic fatty liver disease (NAFLD), independent of obesity or other shared risk factors. Like OSA, NAFLD is a prevalent disorder associated with major adverse health outcomes: Patients with NAFLD may develop cirrhosis, liver failure, and hepatocellular carcinoma. One major finding that has emerged from these studies is that the OSA-NAFLD association is related to the degree of nocturnal hypoxemia in OSA. Animal models have therefore largely focused on intermittent hypoxia, a key manifestation of OSA, to shed light on the mechanisms by which OSA may give rise to the complex metabolic disturbances that are seen in NAFLD. Intermittent hypoxia leads to tissue hypoxia and can result in oxidative stress, mitochondrial dysfunction, inflammation, and overactivation of the sympathetic nervous system, among many other maladaptive effects. In such models, intermittent hypoxia has been shown to cause insulin resistance, dysfunction of key steps in hepatic lipid metabolism, atherosclerosis, and hepatic steatosis and fibrosis, each of which is pertinent to the development and/or progression of NAFLD. However, many intriguing questions remain unanswered: Principally, how aggressively should the clinician screen for NAFLD in patients with OSA, and vice versa? In this review, we attempt to apply the best evidence from animal and human studies to highlight the relationship between these two disorders and to advocate for further trials aimed at defining these relationships more precisely.

NonInvasive Biomarkers in Nonalcoholic Fatty Liver Disease: Are We There Yet?

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. NAFLD encompasses a spectrum of disease ranging from simple steatosis (NAFL) to nonalcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma. However, despite the growing recognition of this important disease burden, there are significant challenges to accurately and noninvasively diagnose the various forms of NAFLD, especially to differentiate benign steatosis from the progressive NASH. This is of utmost importance because although liver biopsy is considered the current imperfect 'gold' standard for diagnosing NASH and staging fibrosis, it is an invasive procedure with significant limitations. Although, a number of noninvasive markers have been or are currently undergoing investigation, until date, no highly sensitive and specific tests are available to differentiate NASH from simple steatosis. At the moment, further investigations are needed before prediction models or blood-based biomarkers become available and acceptable for routine clinical care. There is a great need for developing inexpensive, easily accessible, highly sensitive and specific biomarkers that permit not only the identification of patients at high risk of adverse outcomes, but also the monitoring of disease progression and response after therapeutic interventions.

Histologic Findings of Advanced Fibrosis and Cirrhosis in Patients With Nonalcoholic Fatty Liver Disease Who Have Normal Aminotransferase Levels

OBJECTIVES

Patients with nonalcoholic fatty liver disease (NAFLD) and normal aminotransferase levels may have advanced liver histology. We conducted a study to characterize the prevalence of and factors associated with advanced liver histology in patients with histologically characterized NAFLD and normal aminotransferase levels.

METHODS

We evaluated 534 adults with biopsy-proven NAFLD and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) <40U/L within 3 months of their liver biopsy. Histological phenotypes of primary interest were nonalcoholic steatohepatitis (NASH) with stage 2-3 fibrosis (NASH F2-3) and cirrhosis. Using multiple logistic regression models with Akaike's Information Criteria (AIC), we identified variables associated with these histological phenotypes. We developed and internally validated their clinical prediction models.

RESULTS

The prevalence of NASH F2-F3 and cirrhosis was 19% and 7%, respectively. The best multiple regression AIC model for NASH F2-3 consisted of type 2 diabetes, white race, lower low-density lipoprotein, lower platelet count, higher AST/ALT ratio, higher serum triglycerides, and hypertension. The best AIC model for cirrhosis consisted of lower platelet count, lower AST/ALT ratio, higher body mass index, and female sex. The area under the receiver operator curves of the prediction models were 0.70 (95% confidence interval: 0.65-0.76) for detecting NASH-F2-3 and 0.85 (95% confidence interval: 0.77-0.92) for detecting cirrhosis. When models were fixed at maximum Youden's index, their positive and negative predictive values were 35% and 88% for NASH F2-F3 and 30% and 98% for cirrhosis, respectively.

DISCUSSION

Clinically significant histological phenotypes are observed in patients with NAFLD and normal aminotransferase levels. Our models can assist the clinicians in excluding advanced liver histology in NAFLD patients with normal aminotransferase levels.

Hepatic steatosis in patients undergoing resection of colorectal liver metastases: A target for prehabilitation? A narrative review

The prevalence of elevated intra-hepatic fat (IHF) is increasing in the Western world, either alone as hepatic steatosis (HS) or in conjunction with inflammation (steatohepatitis). These changes to the hepatic parenchyma are an independent risk factor for post-operative morbidity following liver resection for colorectal liver metastases (CRLM). As elevated IHF and colorectal malignancy share similar risk factors for development it is unsurprisingly frequent in this cohort. In patients undergoing resection IHF may be elevated due to excess adiposity or its elevation may be induced by neoadjuvant chemotherapy, termed chemotherapy associated steatosis (CAS). Additionally, chemotherapy is implicated in the development of inflammation termed chemotherapy associated steatohepatitis (CASH). Following cessation of chemotherapy, patients awaiting resection have a 4-6 week washout period prior to resection that is a window for prehabilitation prior to surgery. In patients with NAFLD dietary and pharmacological interventions can reduce IHF within this timeframe but this approach to modifying IHF is untested in this population. In this review, the aetiology of CAS and CASH is reviewed with recommendations to identify those at risk. We also focus on the post-chemotherapy washout period, reviewing dietary interventions applied to the metabolic population and suggest this window may be used as an opportunity to optimise IHF with such a regime as part of a pre-operative prehabilitation programme to produce improved patient outcomes.

Relations of liver fat with prevalent and incident chronic kidney disease in the Framingham Heart Study: A secondary analysis

BACKGROUND & AIMS

Prior studies demonstrated an association between non-alcoholic fatty liver disease and chronic kidney disease (CKD), though data are conflicting. We examined the association between liver fat and prevalent and incident CKD in the Framingham Heart Study (FHS).

METHODS

We included FHS participants who underwent computed tomography (CT) from 2002 to 2005 (n = 1315). After excluding heavy alcohol use (n = 211) and missing covariates (n = 117), the final sample included 987 participants. For the incident CKD analysis, we excluded 73 participants with prevalent CKD. Liver fat was measured by the average liver attenuation on CT. Estimated glomerular filtration rate (eGFR) was obtained using the CKD Epidemiology Collaboration Creatinine-Cystatin C equation, and CKD was defined as eGFR < 60 ml/min/1.73 m² . Microalbuminuria was defined by sex-specific urinary albumin-creatinine ratio cut-offs. Multivariable-adjusted regression models were performed to determine the association between liver fat and CKD.

RESULTS

The prevalence of hepatic steatosis and CKD were 19% and 14% respectively (55.9% women, mean age 60 ± 9 years). After adjusting for covariates, we observed no significant associations between liver fat and CKD, microalbuminuria or eGFR in cross-sectional analyses. We observed positive associations between liver fat, incident microalbuminuria and reduced eGFR in age- and sex-adjusted models; these relationships were not significant in multivariable-adjusted models.

CONCLUSIONS

In this community-based cohort study, we did not observe significant associations between liver fat and prevalent or incident CKD with a median follow-up time of 12.5 years. The association between NAFLD and CKD may be accounted for by shared risk factors; confirmatory studies are needed.

Noninvasive Assessment of Liver Disease in Patients With Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is estimated to afflict approximately 1 billion individuals worldwide. In a subset of NAFLD patients, who have the progressive form of NAFLD termed nonalcoholic steatohepatitis (NASH), it can progress to advanced fibrosis, cirrhosis, hepatocellular carcinoma, and liver-related morbidity and mortality. NASH is typically characterized by a specific pattern on liver histology, including steatosis, lobular inflammation, and ballooning with or without peri-sinusoidal fibrosis. Thus, key issues in NAFLD patients are the differentiation of NASH from simple steatosis and identification of advanced hepatic fibrosis. Until now, liver biopsy has been the gold standard for identifying these 2 critical end points, but has well-known limitations, including invasiveness; rare but potentially life-threatening complications; poor acceptability; sampling variability; and cost. Furthermore, due to the epidemic proportion of individuals with NAFLD worldwide, liver biopsy evaluation is impractical, and noninvasive assessment for the diagnosis of NASH and fibrosis is needed. Although much of the work remains to be done in establishing cost-effective strategies for screening for NASH, advanced fibrosis, and cirrhosis, in this review, we summarize the current state of the noninvasive assessment of liver disease in NAFLD, and we provide an expert synthesis of how these noninvasive tools could be utilized in clinical practice. Finally, we also list the key areas of research priorities in this area to move forward clinical practice.

Noninvasive Evaluation of Liver Function in Morbidly Obese Patients

Background

More than half of the obese patients develop nonalcoholic fatty liver disease (NAFLD), which may further progress to nonalcoholic steatohepatitis (NASH) and cirrhosis. The aim of this study was to assess alterations in liver function in obese patients with a noninvasive liver function test.

Methods

In a prospective cohort study 102 morbidly obese patients undergoing bariatric surgery were evaluated for their liver function. Liver function capacity was determined by the LiMAx® test (enzymatic capacity of cytochrome P450 1A2). Liver biopsy specimens were obtained intraoperatively and classified according to the NAFLD Activity Score (NAS). NASH clinical score was additionally calculated from laboratory and clinical parameters.

Results

Median liver function capacity was 286 (IQR = 141) μg/kg/h. 27% of patients were histologically categorized as definite NASH, 39% as borderline, and 34% as not NASH. A significant correlation was observed between liver function capacity and NAS (r = −0.492; p < 0.001). The sensitivity and specificity of the LiMAx® test to distinguish between definite NASH and not NASH were 85.2% and 82.9% (AUROC 0.859), respectively. According to the NASH clinical scoring system, 14% were classified as low risk, 31% as intermediate, 26% as high, and 29% as very high risk. Liver function capacity is also significantly correlated with the NASH clinical scoring system (r = −0.411; p < 0.001).

Conclusions

Obese patients show a diminished liver function capacity, especially those suffering from type 2 diabetes. The liver function capacity correlates with histological and clinical scoring systems. The LiMAx® test may be a valuable tool for noninvasive screening for NASH in obese patients.

Including Fibroblast Growth Factor-21 in Combined Biomarker Panels Improves Predictions of Liver Steatosis Severity in Children

Background: Previous studies reported conflicting results regarding the association between fibroblast growth factor-21 (FGF-21) and non-alcoholic fatty liver disease (NAFLD). This study aimed to evaluate the feasibility of combining FGF-21, obesity indices, and biochemical tests for predicting high-grade liver steatosis in children. Methods: A total of 203 children and adolescents aged 5-18 years were enrolled, and their anthropometric data, body composition, liver ultrasound score for NAFLD (range, 0-6), biochemical test results, and FGF-21, leptin, and adiponectin levels were analyzed. Children were categorized according to body mass index (BMI) and NAFLD scores. Univariate analysis and multivariate linear regression were used to identify independent predictors for the degree of liver steatosis. The accuracy of the models was also evaluated using a receiver-operating characteristic (ROC) curve. Results: FGF-21 levels were significantly higher in subjects with high-grade liver steatosis (P < 0.001). In obese and overweight children, regression analysis indicated that higher BMI and higher gamma-glutamyl transferase (γ-GT), triglycerides (TG), and FGF-21 levels were independent risk factors strongly correlated with NAFLD scores. FGF-21 combined with any of the above parameters showed a larger area under the ROC (AUROC, 0.861-0.873) than either parameter used alone. Overall, the best performance was obtained by combing FGF-21, γ-GT, and TG, with an AUROC of 0.871, specificity of 82.54%, and sensitivity of 83.78% for predicting high-grade liver steatosis. Conclusion: BMI, FGF-21, γ-GT, and TG levels were strongly correlated with liver steatosis severity. Including FGF-21 in the biomarker panels may improve the accuracy for identifying obese and overweight children with high-grade liver steatosis.

Renal Dysfunction in Patients With Nonalcoholic Fatty Liver Disease is Related to the Presence of Diabetes Mellitus and Severity of Liver Disease

BACKGROUND AND AIMS

There is sparse data on the prevalence of renal dysfunction in patients with nonalcoholic fatty liver disease (NAFLD). The aim of the present study was to evaluate the presence of renal dysfunction in patients with NAFLD and correlate it with the severity of liver disease.

METHODS

One hundred nonalcoholic patients with ultrasound showing hepatic steatosis were enrolled into the study after exclusion of other causes. Presence of renal dysfunction was estimated by glomerular filtration rate and by evaluating 24 h urinary protein and microalbumin. Various risk factors including components of metabolic syndrome, severity of hepatic steatosis (as assessed on ultrasound), hepatic necro-inflammation (as assessed by hepatic transaminases) and hepatic fibrosis (as assessed by transient elastography) were correlated with the presence of renal dysfunction.

RESULTS

Twenty eight (28%) patients with NAFLD had evidence of impaired renal function with 5 (5%) having abnormal glomerular filtration rate, 18 (18%) having significant proteinuria and 5 (5%) having both. Presence of type 2 diabetes mellitus, raised hepatic transaminases and advanced fibrosis on transient elastography were found as independent predictors of impaired renal function with raised hepatic transaminases having the best sensitivity (89%) and presence of advanced fibrosis the best specificity (90%). A model comprising of these three parameters had good accuracy (AUROC = 0.763) in predicting impaired renal function in patients with NAFLD.

CONCLUSIONS

Around one-third of patients with NAFLD have impaired renal functions. Prevalence of impaired renal function in patients with NAFLD is dependent on the severity of liver disease and presence of diabetes mellitus.

Magnitude of Nonalcoholic Fatty Liver Disease: Western Perspective

The incidence of nonalcoholic fatty liver disease (NAFLD) is continuing to rise worldwide, and it is estimated that this disquieting trend will continue for another 10-15 years before prevalence begins to decrease. NAFLD is the hepatic manifestation of metabolic syndrome. As obesity, diabetes, and other lifestyle-related diseases continue to rise, the spectrum of NAFLD, e.g., nonalcoholic steatohepatitis, liver fibrosis, liver cirrhosis, liver-related morbidity, and mortality, will increase in parallel. Its widespread prevalence and associated economic burden have drawn significant attention, and a multitude of pharmaceutical companies are participating in active research trying to find a "cure". Unfortunately, as of now, no targeted treatment exists to treat this condition, and therefore, emphasis has been on its prevention. The current review focuses on the epidemiology, clinical characteristics, risk factors, and clinical outcomes of NAFLD in Western countries. It is important to understand the magnitude of NAFLD and its risk factors in Western countries where the prevalence of NAFLD has now reached epidemic proportions to identify the best strategy to prevent and possibly control this epidemic.

Serum CK 18-M30 reflect liver pathological severity during NAFLD progression in a rat model

BACKGROUND

CK 18-M30 was increased in patients with NAFLD. However, little is known about the relationship between CK 18-M30 and NAFLD progression. We aimed to analyze the variety of CK 18-M30 and other metabolism indices during NAFLD progression. Meanwhile, we aimed to investigate the correlation between CK 18-M30 and liver pathology during NAFLD progression.

MATERIALS AND METHODS

Rats were fed with high sucrose and high fat diet for building NAFLD models. We detected liver pathology by hematoxylin-eosin (HE) staining. We also detected serum CK 18-M30 and metabolism indices including liver enzymes, serum lipids and glycometabolism indices.

RESULTS

The aggravating degree of liver pathology appeared with prolonged feeding period. The relevance of CK 18-M30 to the severity of liver pathology were higher relative to other indices.

CONCLUSION

Our results suggested the significance of CK 18-M30 in the progression of NAFLD and provided new evidence for the early diagnosis and prognostic estimation of NAFLD.

Long-term effect of bariatric surgery on resolution of nonalcoholic steatohepatitis (NASH): An external validation and application of a clinical NASH score

BACKGROUND

Nonalcoholic steatohepatitis (NASH) is an important etiology of end-stage liver disease. Long-term effect of bariatric surgery in improvement of NASH is not clear.

OBJECTIVES

To validate a scoring system for predicting NASH in morbidly obese patients and using it to evaluate the long-term effect of bariatric surgery on NASH.

SETTING

Tertiary referral hospital, Taiwan.

METHODS

A new 5-point clinical NASH (C-NASH) score incorporating body mass index, alanine aminotransferase, and triglyceride was validated in a group of 307 bariatric patients (mean age 30.2 years, incorporating body mass index 45.0 kg/m²) with concurrent liver biopsy from 2003 to 2008. Remission of NASH in 5741 obese patients undergoing bariatric/metabolic surgery with long-term follow-up was then evaluated using the C-NASH score.

RESULTS

Among 307 patients with liver biopsy, the prevalence of NASH was 44.0%. At baseline, the NASH group had significantly worse fasting glucose levels, triglycerides, uric acid, aspartate aminotransferase, alanine aminotransferase, gamma glutamyl transferase, and glycated hemoglobin. The diagnostic sensitivity of C-NASH score was 84.4%, and the accuracy was 68.4%. Among 5741 bariatric patients, the prevalence of high risk for NASH evaluated by C-NASH score was 40.9%. Postoperative follow-up showed good weight loss and almost complete remission of high risk for NASH up to 10 years. Patients with gastric banding had less weight loss, higher mean level of C-NASH score, and a higher incidence of high risk for NASH compared with other procedures at follow-up.

CONCLUSION

This study demonstrated that improvement in C-NASH score suggesting remission of NASH is durable up to 10 years in all kinds of bariatric procedures.

Noninvasive Tests Do Not Accurately Differentiate Nonalcoholic Steatohepatitis From Simple Steatosis: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Nonalcoholic fatty liver disease is a rapidly increasing health problem. Liver biopsy analysis is the most sensitive test to differentiate between nonalcoholic steatohepatitis (NASH) and simple steatosis (SS), but noninvasive methods are needed. We performed a systematic review and meta-analysis of noninvasive tests for differentiating NASH from SS, focusing on blood markers.

METHODS

We performed a systematic search of the PubMed, Medline and Embase (1990-2016) databases using defined keywords, limited to full-text papers in English and human adults, and identified 2608 articles. Two independent reviewers screened the articles and identified 122 eligible articles that used liver biopsy as reference standard. If at least 2 studies were available, pooled sensitivity (sens_p) and specificity (spec_p) values were determined using the Meta-Analysis Package for R (metafor).

RESULTS

In the 122 studies analyzed, 219 different blood markers (107 single markers and 112 scoring systems) were identified to differentiate NASH from simple steatosis, and 22 other diagnostic tests were studied. Markers identified related to several pathophysiological mechanisms. The markers analyzed in the largest proportions of studies were alanine aminotransferase (sens_p, 63.5% and spec_p, 74.4%) within routine biochemical tests, adiponectin (sensp, 72.0% and spec_p, 75.7%) within inflammatory markers, CK18-M30 (sens_p, 68.4% and spec_p, 74.2%) within markers of cell death or proliferation and homeostatic model assessment of insulin resistance (sens_p, 69.0% and spec_p, 72.7%) within the metabolic markers. Two scoring systems could also be pooled: the NASH test (differentiated NASH from borderline NASH plus simple steatosis with 22.9% sens_p and 95.3% spec_p) and the GlycoNASH test (67.1% sens_p and 63.8% spec_p).

CONCLUSION

In the meta-analysis, we found no test to differentiate NASH from SS with a high level of pooled sensitivity and specificity (≥80%). However, some blood markers, when included in scoring systems in single studies, identified patients with NASH with ≥80% sensitivity and specificity. Replication studies and more standardized study designs are urgently needed. At present, no marker or scoring system can be recommended for use in clinical practice to differentiate NASH from simple steatosis.

A Case of Concomitant Obstructive Sleep Apnea and Non-Alcoholic Steatohepatitis Treated With CPAP Therapy

Obstructive sleep apnea syndrome is a disorder of sleep breathing that is a result of recurrent and intermittent hypoxia during sleep induced by the repeated partial or complete collapse of the upper airway, eventually causing chronic intermittent hypoxia. Non-alcoholic fatty liver disease is divided into non-alcoholic fatty liver and non-alcoholic steatohepatitis. Animal and human studies showed that obesity is associated with chronic liver hypoxia, even in the presence of systemic normoxia causing inflammation and release of cytokines. A "two-hit" model has been proposed. The first hit is characterized by insulin resistance and excess hepatic lipid accumulation secondary to abnormal fatty acid metabolism. Oxidative stress and inflammation are thought to comprise the second hit. Gold standard for the diagnosis of non-alcoholic steatohepatitis is a liver biopsy. Many clinical scores and non-invasive tools are used for the diagnosis of non-alcoholic steatohepatitis. Conservative management with lifestyle modifications including diet, exercise and weight loss remains the therapy of choice today. We present a case report of a 39-year-old man who was diagnosed with concomitant non-alcoholic steatohepatitis and severe obstructive sleep apnea. He was started treatment with continuous positive airway pressure and demonstrated excellent adherence to therapy for 6 years, with concomitant obstructive sleep apnea and non-alcoholic steatohepatitis which reversed with prolonged optimal continuous positive airway pressure therapy. Physical examination remained unremarkable except for morbid obesity. His abdominal girth, as well as body mass index, remained unchanged. After 6 years of optimal continuous positive airway pressure therapy, liver enzymes and relevant lipid panel normalized, suggesting reversal of non-alcoholic steatohepatitis.

Racial and Ethnic Disparities in Nonalcoholic Fatty Liver Disease Prevalence, Severity, and Outcomes in the United States: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the United States, affecting 75-100 million Americans. However, the disease burden may not be equally distributed among races or ethnicities. We conducted a systematic review and meta-analysis to characterize racial and ethnic disparities in NAFLD prevalence, severity, and prognosis.

METHODS

We searched MEDLINE, EMBASE, and Cochrane databases through August 2016 for studies that reported NAFLD prevalence in population-based or high-risk cohorts, NAFLD severity including presence of nonalcoholic steatohepatitis (NASH) and significant fibrosis, and NAFLD prognosis including development of cirrhosis complications and mortality. Pooled relative risks, according to race and ethnicity, were calculated for each outcome using the DerSimonian and Laird method for a random-effects model.

RESULTS

We identified 34 studies comprising 368,569 unique patients that characterized disparities in NAFLD prevalence, severity, or prognosis. NAFLD prevalence was highest in Hispanics, intermediate in Whites, and lowest in Blacks, although differences between groups were smaller in high-risk cohorts (range 47.6%-55.5%) than population-based cohorts (range, 13.0%-22.9%). Among patients with NAFLD, risk of NASH was higher in Hispanics (relative risk, 1.09; 95% CI, 0.98-1.21) and lower in Blacks (relative risk, 0.72; 95% CI, 0.60-0.87) than Whites. However, the proportion of patients with significant fibrosis did not significantly differ among racial or ethnic groups. Data were limited and discordant on racial or ethnic disparities in outcomes of patients with NAFLD.

CONCLUSIONS

In a systematic review and meta-analysis, we found significant racial and ethnic disparities in NAFLD prevalence and severity in the United States, with the highest burden in Hispanics and lowest burden in Blacks. However, data are discordant on racial or ethnic differences in outcomes of patients with NAFLD.

Non-invasive assessment of non-alcoholic fatty liver disease: Clinical prediction rules and blood-based biomarkers

The correct identification of patients at increased risk of non-alcoholic steatohepatitis (NASH) and advanced fibrosis is a critical step in the assessment of non-alcoholic fatty liver disease (NAFLD). Since liver biopsy is invasive, expensive and prone to sampling error, several clinical prediction rules and blood-based biomarkers have been developed as attractive and affordable alternatives for identification of patients at high risk of NASH and advanced fibrosis. Current biomarkers constitute predictive models (e.g. NAFLD fibrosis score, FIB-4 index and BARD score) or direct measures of inflammation (e.g. circulating keratin 18 fragments), or fibrosis (e.g. FibroTest®, ELF™ or Pro-C3 tests). In the clinical setting, biomarkers may discriminate between patients with NASH or advanced fibrosis, predict dynamic changes in NASH/fibrosis over time, and provide long-term prognostic information. Although clinically useful, current biomarker predictions may be influenced by hepatic and extrahepatic conditions (e.g. age, patient comorbidities, and fibrosis or NASH prevalence), which may lead to inaccurate estimates in small subsamples of patients. No highly sensitive and specific tests are available to differentiate NASH from simple steatosis. However, diagnostic accuracy can be improved by combining blood biomarkers. NAFLD fibrosis score and FIB-4 index are both cost-effective and highly sensitive tools to exclude patients with advanced fibrosis. Moreover, their higher scores may identify patients at higher risk of non-liver- and liver-related morbidity and mortality. More expensive tests such as FibroTest or ELF are more specific for detection of patients with significant and advanced fibrosis. Recent efforts have concentrated on "omics" approaches for developing and validating novel biomarkers. Herein, we describe currently available clinical prediction rules and blood-based biomarkers for identifying NASH and advanced fibrosis in patients with NAFLD, discussing their advantages and disadvantages, as well as their potential clinical utility for predicting dynamic changes over time and identifying patients at increased risk of adverse outcomes.

Evolution of Liver Steatosis Quantified by MR Imaging and MR Spectroscopy, in Morbidly Obese Patients Undergoing Sleeve Gastrectomy: Short-Term Outcomes

BACKGROUND

Currently, the standard procedure used to evaluate hepatic steatosis is the liver biopsy. This is an invasive practice that presents inherent risks. Increasing evidence suggests that magnetic resonance imaging (MRI) and MR spectroscopy (MRS) may represent an accurate method to determine the hepatic lipid content. The aim of this study was to evaluate the effect of sleeve gastrectomy on liver steatosis, quantified by MRI and MRS.

PATIENTS AND METHODS

A prospective observational study of patients undergoing laparoscopic sleeve gastrectomy was performed. All patients underwent a MRI and a MRS study 2 weeks before the intervention and 6 months after the surgery. Anthropometric, biochemical, and radiological parameters were analyzed.

RESULTS

Twenty-three patients were included, 21 females and 2 males, with a mean age of 47.6 ± 10.6 years and mean pre-op BMI 47.6 ± 6.7 Kg/m². Six months after surgery, mean BMI was 32.2 ± 5.1 Kg/m², with a mean excess weight loss of 68.2 ± 18.6%. Mean preoperative hepatic volume was 1999.9 ± 436.2 ml and 6 months after surgery it decreased to 1568 ± 170.3 ml (p = 0.005). Mean preoperative percentage of lipid content was 14.2 ± 15.4% and 6 months after surgery, it decreased to 4.3 ± 3.2% (p = 0.007). A significant reduction of steatosis grade was observed, with disappearance of preoperative steatosis in 54.9% of the patients.

CONCLUSION

Six months after sleeve gastrectomy, a significant reduction of liver steatosis is observed, as demonstrated by reduction in the percentage of intrahepatocitary lipids and liver volume, determined by MRS and MRI. These imaging techniques can be considered as noninvasive, accurate methods for monitoring liver steatosis in morbidly obese patients undergoing bariatric surgery.

Protective effect of black relative to white race against non-alcoholic fatty liver disease in patients with severe obesity, independent of type 2 diabetes

Severe obesity (body mass index ⩾35 kg m^-2) and type 2 diabetes (T2D) are potent and additive risk factors for non-alcoholic fatty liver disease (NAFLD), including non-alcoholic steatohepatitis (NASH). Scant available evidence indicates that black relative to white patients with severe obesity are less susceptible to NAFLD, but it is unclear if T2D abolishes this apparent racial disparity. Therefore, we compared biopsy-proven NAFLD and its progression between black (n=71) and white (n=155) patients with severe obesity stratified by presence or absence of T2D. Although prevalence of T2D was similar between races (37%, P>0.9), whites were significantly more likely than blacks to have NAFLD, NASH and advanced fibrosis (defined as bridging fibrosis and/or cirrhosis). Importantly, T2D was associated with increased odds of NAFLD, NASH and advanced fibrosis (defined as bridging fibrosis or cirrhosis) in whites only (P<0.05). In turn, a higher proportion of blacks than whites with T2D were free of NAFLD (58 versus 22%, P<0.01). These preliminary findings question translation of the powerful interconnection between T2D and NAFLD in whites with severe obesity to blacks and point to an important role of race in the pathophysiology and treatment of these diseases.

The association of nonalcoholic steatohepatitis and obstructive sleep apnea

BACKGROUND AND AIM

The association between obstructive sleep apnea (OSA) and abnormal liver enzymes has been reported in multiple studies. The existing literature regarding the relationship between OSA and nonalcoholic steatohepatitis (NASH) is conflicting. Thus we aimed to determine the relationship between OSA and NASH from a large database.

PATIENTS AND METHODS

A cross-sectional study was performed using the 2012 Nationwide Inpatient Sample. We identified adult patients (18-90 years) who had a diagnosis of OSA using the International Classification of Diseases 9th version codes. The control group was comprised of adult individuals with no discharge records of OSA. NASH diagnosis was also identified using the International Classification of Diseases 9th version codes. The association between OSA and NASH was calculated using univariable and multivariable logistic regression.

RESULTS

A total of 30 712 524 hospitalizations were included. The OSA group included 1 490 150 patients versus 29 222 374 in the control non-OSA group. The OSA group average age was 61.8±0.07 years (44.2% females) compared with 57.0±0.11 years (60.1% females) in the non-OSA group. NASH prevalence was significantly higher in the OSA group compared with the non-OSA group [2% (95% confidence interval (CI): 1.9, 2.1) vs. 0.65% (95% CI: 0.63, 0.66), P<0.001]. After adjusting for obesity, diabetes, hypertension, dyslipidemia, the metabolic syndrome and Charlson comorbidity index, OSA patients were three times more likely to have NASH [adjusted odds ratio: 3.1 (95% CI: 3.0-3.3), P<0.001].

CONCLUSION

Patients with OSA are three times more likely to have NASH compared with patients without OSA after controlling for other confounders. These data indicate that OSA should be considered as an independent risk factor for developing NASH.

Improvement of nonalcoholic fatty liver disease in morbidly obese patients after sleeve gastrectomy: association of ultrasonographic findings with lipid profile and liver enzymes

BACKGROUND

After bariatric surgery an improvement or even complete resolution of nonalcoholic fatty liver disease (NAFLD) in morbidly obese patients is achieved, but little is known about the effect of laparoscopic sleeve gastrectomy (LSG).

PATIENTS AND METHODS

A prospective observational study of patients undergoing LSG was performed. An abdominal ultrasonography and blood sample extraction (investigating liver enzymes and lipid profile) were performed preoperatively and 12 months after surgery.

RESULTS

Fifty patients were included in the study. Preoperatively, 84% of the patients presented liver steatosis. A significant reduction of steatosis could be observed 12 months after surgery (p < .001). Preoperative degree of steatosis showed a direct correlation with AST (p = .008) and ALT (p = .007) and an inverse correlation with HDL-cholesterol (p = .019). The reduction of liver steatosis showed an inverse correlation with the increase of HDL-cholesterol between pre- and postoperative determinations (p = .008).

CONCLUSIONS

Liver steatosis, as measured by ultrasonography, improves after sleeve gastrectomy, achieving a complete resolution in 90% of the cases. Preoperative steatosis correlates directly with AST and ALT levels and inversely with HDL-cholesterol. The postoperative increase of HDL-cholesterol shows an inverse correlation with liver steatosis improvement, suggesting that it could be a good marker for monitoring the postoperative liver status.

Liver steatosis: The new epidemic of the Third Millennium. Benign liver state or silent killer?

Until the end of the 90's of the last century, rather little attention was paid to the issue of the non-alcoholic fatty liver disease (NAFLD), perhaps due to the fact that the newly discovered hepatitis C virus did attract a paramount interest of hepatologists and researchers. On the other side, fatty liver was considered a relatively uncommon cause of liver damage, occurring almost exclusively in obese females, often associated with non-insulin dependent diabetes mellitus (NIDDM), and with a relatively benign prognosis. Due to the complexity of international available guidelines, we decide to approach the main unsolved issues on this topic in the form of a dialog between a hepatologist and a man suffering from NAFLD, trying to give evidence-based answers to the more frequently asked questions from patients and their GPs. This is the third instalment of the Trilogy of Dr. Calm, a skilled hepatologist who will try to clearly explain to his patient Mr. Frightened the natural history of NAFLD, the diagnostic workup, indications for liver biopsy and suggested medical treatments, advicing him on the importance of dietary intervention and lifestyle modifications.