Hepatic Steatosis: Etiology, Patterns, and Quantification

Development of a Deep Learning Model for Classification of Hepatic Steatosis from Clinical Standard Ultrasound

OBJECTIVE

Early detection and monitoring of hepatic steatosis can help establish appropriate preventative measures against progression to more advanced disease. We aimed to develop a deep learning (DL) program for classification of hepatic steatosis from standard-of-care grayscale ultrasound (US) images.

METHODS

In this single-center retrospective study, we utilized grayscale US images from January 1, 2010, to October 23, 2022, labeled with magnetic resonance imaging (MRI) proton density fat fraction (MRI-PDFF) to develop a DL multi-instance program for differentiating normal (S0) from steatotic liver (S1/2/3) and normal/mild steatosis (S0/1) from moderate/severe steatosis (S2/3). Diagnostic performances were assessed with area under the receiver operating characteristic curves (AUC), sensitivity, specificity and balanced accuracy with 95% confidence interval (CI).

RESULTS

A total of 403 patients with 403 US exams were included: 171 (42%) were normal (S0: MRI-PDFF <5%), 154 (38%) had mild steatosis (S1: MRI-PDFF 5-17.4%), 29 (7%) had moderate steatosis (S2: MRI-PDFF >17.4%-22.1%) and 49 (12%) had severe steatosis (S3: MRI-PDFF >22.1%). The dataset was split to include 322 patients in train/validation and 81 patients in a holdout test set (kept blind). The S0 versus S1/2/3 model achieved 81.3% (95% CI 72.1-90.5) AUC, 81.1% (70.6-91.6) sensitivity, 71.4% (54.7-88.2) specificity and 76.3% (66.4-86.2) balanced accuracy. The S0/1 versus S2/3 model achieved 95.9% (89-100) AUC, 87.5% (71.3-100) sensitivity, 96.9% (92.7-100) specificity and 92.2% (83.8-100) balanced accuracy. A multi-class model achieved a sensitivity of 71.4% (54.7-88.2) for S0, 67.6% (52.5-82.7) for S1 and 87.5% (71.3-100) for S2/3; specificity for the same model was 81.1% (70.6-91.6) for S0, 77.3% (64.9-89.7) for S1 and 96.9% (92.7-100) for S2/3.

CONCLUSION

Our DL program offered high sensitivity and accuracy in detecting and categorizing hepatic steatosis from standard-of-care ultrasound.

Practical approach to quantitative liver and pancreas MRI in children

Quantitative abdominal magnetic resonance imaging (MRI) offers non-invasive, objective assessment of diseases in the liver, pancreas, and other organs and is increasingly being used in the pediatric population. Certain quantitative MRI techniques, such as liver proton density fat fraction (PDFF), R2* mapping, and MR elastography, are already in wide clinical use. Other techniques, such as liver T1 mapping and pancreas quantitative imaging methods, are emerging and show promise for enhancing diagnostic sensitivity and treatment monitoring. Quantitative imaging techniques have historically required a breath-hold, making them more difficult to implement in the pediatric population. However, technological advances, including free-breathing techniques and compressed sensing imaging, are making these techniques easier to implement. The purpose of this article is to review current liver and pancreas quantitative techniques and to provide a practical guide for implementing these techniques in pediatric practice. Future directions of liver and pancreas quantitative imaging will be briefly discussed.

The zebrafish embryo as a model for chemically-induced steatosis: A case study with three pesticides

There is an increasing incidence and prevalence of fatty liver disease in the western world, with steatosis as the most prevalent variant. Known causes of steatosis include exposure to food-borne chemicals, and overconsumption of alcohol, carbohydrates and fat, and it is a well-known side effect of certain pharmaceuticals such as tetracycline, amiodarone and tamoxifen (drug-induced hepatic steatosis). Mechanistic knowledge on chemical-induced steatosis has greatly evolved and has been organized into adverse outcome pathways (AOPs) describing the chain of events from first molecular interaction of a substance with a biological system to the adverse outcome, intrahepatic lipid accumulation. In this study, three known steatosis-inducing pesticides (imazalil, clothianidin, and thiacloprid) were tested for their ability to induce hepatic triglyceride accumulation in the zebrafish (Danio rerio) embryo (ZFE) at 5 days post fertilization, both as single compounds and equipotent binary mixtures. The results indicate that the ZFE is very well applicable as a higher tier testing model to confirm effects in downstream key events in AOPs, that is, chemically-induced triglyceride accumulation in the whole organism and production of visible steatosis. Moreover, dose addition could be concluded for binary mixtures of substances with similar and with dissimilar modes of action.

MRI Dixon Fat-Corrected Look-Locker T1 Mapping for Quantification of Liver Fibrosis and Inflammation-A Comparison With the Non-Fat-Corrected Shortened Modified Look-Locker Inversion Recovery Technique

OBJECTIVES

This study evaluates the impact of liver steatosis on the discriminative ability for liver fibrosis and inflammation using a novel Dixon water-only fat-corrected Look-Locker T1 mapping sequence, compared with a standard shortened Modified Look-Locker Inversion Recovery (shMOLLI) sequence, with the aim of overcoming the limitation of steatosis-related confounding in liver T1 mapping.

MATERIALS AND METHODS

3 T magnetic resonance imaging of the liver including the 2 T1 mapping sequences and proton density fat fraction (PDFF) was prospectively performed in 24 healthy volunteers and 38 patients with histologically proven liver fibrosis evaluated within 90 days of liver biopsy. Paired Mann-Whitney test compared sequences between participants with and without significant liver steatosis (PDFF cutoff 10%), and unpaired Kruskal-Wallis test compared healthy volunteers to patients with early (F0-2) and advanced (F3-4) liver fibrosis, as well as low (A0-1) and marked (A2-3) inflammatory activity. Univariate and multivariate logistic regression models assessed the impact of liver steatosis on both sequences.

RESULTS

Dixon_W T1 was higher than shMOLLI T1 in participants without steatosis (median 896 ms vs 890 ms, P = 0.04), but lower in participants with liver steatosis (median 891 ms vs 973 ms, P < 0.001). Both methods accurately differentiated between volunteers and patients with early and advanced fibrosis (Dixon_W 849 ms, 910 ms, 947 ms, P = 0.011; shMOLLI 836 ms, 918 ms, 978 ms, P < 0.001), and those with mild and marked inflammation (Dixon_W 849 ms, 896 ms, 941 ms, P < 0.01; shMOLLI 836 ms, 885 ms, 978 ms, P < 0.001). Univariate logistic regression showed slightly lower performance of the Dixon_W sequence in differentiating fibrosis (0.69 vs 0.73, P < 0.01), compensated by adding liver PDFF in the multivariate model (0.77 vs 0.75, P < 0.01).

CONCLUSIONS

Dixon water-only fat-corrected Look-Locker T1 mapping accurately identifies liver fibrosis and inflammation, with less dependency on liver steatosis than the widely adopted shMOLLI T1 mapping technique, which may improve its predictive value for these conditions.

The safety, tolerability and clinical impact of pre-operative very low-calorie diet prior to non-bariatric abdominal surgery: a systematic review

BACKGROUND

The use of pre-operative very low-calorie diets (VLCD) is established within bariatric and gallbladder surgery. However, their use in patients with high BMI and hepatic steatosis (HS) requiring upper abdominal procedures is unclear. This review aims to assess the safety, adherence, and outcomes of a pre-operative VLCD prior to non-bariatric elective surgery.

METHODS

A systematic search on PubMed MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL and AMED was performed to identify the included studies. Studies were included, if they administered a VLCD to patients undergoing non-bariatric elective surgery and reported on outcomes.

RESULTS

Eight studies were included in this review and all administered a VLCD through either dietician led diet plans or meal replacement shakes. The adherence to the VLCD was heterogeneously measured but was excellent overall with a good safety profile. The VLCD was able to significantly reduce HS and resulted in a less technically difficult operation with reduced intra-operative blood loss. There was no significant impact on intraoperative or early post-operative outcomes.

CONCLUSION

This review highlights that a VLCD can be administered safely during the pre-operative period and overall adherence is excellent, however heterogeneously measured. There was an overall positive impact on reducing hepatic steatosis, operative difficulty and intraoperative blood loss, however no significant impact on overall morbidity and mortality.

Interobserver Reproducibility of Ultrasound Attenuation Imaging Technology in Liver Fat Quantification

PURPOSE

This study aims to investigate the interobserver variability in the quantitative assessment of liver fat content using ultrasound attenuation imaging technology (USAT).

METHODS

This prospective, single-center study included 96 adult patients who were either diagnosed with or suspected of having metabolic dysfunction-associated steatotic liver disease. Independent observers, blinded to each other's assessments, evaluated hepatic steatosis visually and through USAT measurements. Separate measurements were taken at five intercostal and subcostal sites, and the median values of these measurements were recorded. The correlation between USAT measurements and visual steatosis grades was examined using Spearman's correlation test. Intraclass correlation coefficient (ICC) and Bland-Altman analysis were used to evaluate the interobserver variability of USAT measurements.

RESULTS

Interobserver agreement for USAT measurements was excellent for the intercostal examination and good for the subcostal examination (p < 0.001). Body mass index did not significantly affect the level of interobserver agreement. Interobserver variability in Bland-Altman plots of USAT measurements was within the 95% limits of agreement. USAT measurements correlated very strongly with the visual degree of hepatic steatosis, both intercostal and subcostal (p < 0.001). USAT measurements were also significantly different between different visual degrees of hepatic steatosis (p < 0.001).

CONCLUSION

In the assessment of hepatic steatosis, USAT measurements obtained from the intercostal space showed excellent agreement in terms of interobserver reproducibility.

Evaluation of Liver Parenchyma in Dogs with Hyperlipidemia Using Ultrasound Attenuation Imaging (ATI)

(1) Background: Ultrasound attenuation imaging (ATI) is an innovative technique that allows for the evaluation of the degree of lipid infiltration of the liver parenchyma in a simple and non-invasive way. The objective of this study was to verify the applicability of the ATI method in the evaluation of hyperlipidemia. (2) Methods: This study included 53 dogs between January 2021 and December 2022, of which 21 were healthy (A) and 32 had hyperlipidemia (B). The dogs of Group B were divided into mild hyperlipidemic (B1; n = 15) and moderate/severe hyperlipidemic (B2; n = 17). Each dog underwent biochemical examination, B-mode ultrasound and ATI investigation at the liver level via a right intercostal approach. (3) Results: The mean AC value was significantly higher in Group B (0.95 ± 0.23 dB/cm/MHz) compared to Group A (0.81 ± 0.10 dB/cm/MHz). No statistically significant differences were highlighted regarding the ATI values between the subjects with mild and moderate/severe hyperlipidemia. (4) Conclusion: ATI could be a promising method for the non-invasive evaluation of hepatic steatosis in veterinary medicine.

I thought it was a hemangioma! A pictorial essay about common and uncommon liver hemangiomas' mimickers

Focal liver lesions are frequently encountered during imaging studies, and hemangiomas represent the most common solid liver lesion. Liver hemangiomas usually show characteristic imaging features that enable characterization without the need for biopsy or follow-up. On the other hand, there are many benign and malignant liver lesions that may show one or more imaging features resembling hemangiomas that radiologists must be aware of. In this article we will review the typical imaging features of liver hemangiomas and will show a series of potential liver hemangiomas' mimickers, giving radiologists some hints for improving differential diagnoses. CRITICAL RELEVANCE STATEMENT: The knowledge of imaging features of potential liver hemangiomas mimickers is fundamental to avoid misinterpretation. KEY POINTS: Liver hemangiomas typically show imaging features that enable avoiding a biopsy. Many benign and malignant liver lesions show imaging features resembling hemangiomas. Radiologists must know the potentially misleading imaging features of hemangiomas' mimickers.

Correlation between Serum Levels of Nitric Oxide and Adropin and Erectile Dysfunction in Males with Nonalcoholic Fatty Liver Disease: An Observational Study

The current study aimed to evaluate the serum levels of nitric oxide (NO) and adropin in males with non-alcoholic fatty liver disease (NAFLD) induced erectile dysfunction (ED) and NAFLD patients without ED and controls. The current study selected 165 participants from the hepatology department from November 2021 to November 2022. The patients were either suffering from NAFLD with normal liver functions or non-alcoholic steatohepatitis with abnormal liver functions. They were diagnosed by abdominal ultrasonography. Participants were evaluated using the validated Arabic version of the International Index of Erectile Function (ArIIEF-5), the Arabic form of the Generalized Anxiety Disorder-7 (GAD-7) questionnaire and the Patient Health Questionnaire-9 (PHQ-9). Noteworthy, there were significant positive correlations between ArIIEF-5 score, NO, adropin and total testosterone (r = 0.380, p = 0.001; r = 0.507, p =  < 0.001; r = 0.246, p = 0.038, respectively). Meanwhile, there were significant negative correlations between ArIIEF-5 score, creatinine, duration of the disease and scores of GAD-7 and PHQ-9 (r = -0.656, p =  < 0.001; r = -0.368, p = 0.002; r = -0.663, p =  < 0.001; r = -0.248, p = 0.037, respectively). Finally, a linear regression analysis revealed that GAD-7, creatinine, and adropin were the only strong independent predictors of ArIIEF-5, as the 95% confidence interval in the form of upper and lower bounds was -0.349, -0.843, p < 0.001, -6.507, -18.402, p < 0.001, 0.476, 0.117, and p 0.002, respectively. Impaired NO and adropin levels play a potential role in the development of ED in patients with NAFLD.

Codonopsis pilosula polysaccharides (CPP) intervention alleviates sterigmatocystin (STC)-induced liver injury and gut microbiota dysbiosis

Codonopsis pilosula polysaccharides (CPP), the main active ingredient of Codonopsis pilosula, has gained significant attention as a liver-protective agent. Previous studies have demonstrated that CPP could alleviate gut microbiota dysbiosis in colitis or obese mice. However, the effects of CPP on mycotoxin-induced liver injury and gut microbiota dysbiosis are still poorly understood. In this study, we aimed to investigate the protective effects of CPP on sterigmatocystin (STC)-induced liver injury, as well as its regulatory effects on gut microbiota. Our results revealed that CPP intervention significantly alleviated STC-induced liver injury, as evidenced by decreased liver index, reduced liver histopathological changes, and modulation of related molecular markers. Additionally, we found that CPP could alleviate liver injury by reducing liver inflammation and oxidative stress, inhibiting hepatocyte apoptosis, and regulating lipid metabolism. Notably, we also observed that CPP could alleviate STC-induced gut microbiota dysbiosis by modulating the diversity and richness of gut microbiota, suggesting that gut microbiota modulation may also serve as a mechanism for CPP-mediated remission of liver injury. In summary, our study not only provided a new theoretical basis for understanding the hepatotoxicity of STC and the protective effects of CPP against STC-induced liver injury, but also provided new perspectives for the application of CPP in the fields of food, healthcare products, and medicine.

Obesity, liver steatosis and metabolic syndrome: The hidden enemies in transfusion-dependent thalassaemia

In their paper, the authors quantified liver iron concentration (LIC) and hepatic steatosis (HS) using MRI-T2* technology in transfusion-dependent thalassaemia (TDT) patients and healthy controls and found that the prevalence of HS among patients with TDT was 36.4%. In comparison with healthy controls, the hepatic fat fraction (FF) was significantly higher in the TDT population (p = 0.013). Active hepatitis C virus infection, body mass index (BMI) and LIC were independent predictors of HS. An inverse correlation between hepatic FF and high-density lipoprotein cholesterol (p = 0.042) and a significant association of high glycaemia level (p = 0.037) with higher hepatic FF and a significant relationship (p = 0.026) between HS and higher BMI (though in a 'lean' group of patients) in TDT patients indicated that 'metabolic syndrome' was present in this subset with TDT. The impact of metabolic syndrome on TDT, including cardiac disease unrelated to iron overload, needs further study. Commentary on: Ricchi et al. Liver steatosis in patients with transfusion-dependent thalassaemia. Br J Haematol 2024;204:2458-2467.

Role of formyl peptide receptor 2 in steatosis of L02 cells exposed to Mono-(2-ethylhexyl) phthalate

Mono-(2-ethylhexyl) phthalate (MEHP) can accumulate in the liver and then lead to hepatic steatosis, while the underlying mechanism remains unclear. Inflammation plays an important role in the disorder of hepatic lipid metabolism. This study aims to clarify the role of the inflammatory response mediated by formyl peptide receptor 2 (FPR2) in steatosis of L02 cells exposed to MEHP. L02 cells were exposed to MEHP of different concentrations and different time. A steatosis model of L02 cells was induced with oleic acid and the cells were exposed to MEHP simultaneously. In addition, L02 cells were incubated with FPR2 antagonist and then exposed to MEHP. Lipid accumulation was determined by oil red O staining and extraction assay. The indicators related to lipid metabolism and inflammatory response were measured with appropriate kits. The relative expression levels of FPR2 and its ligand were determined by Western blot, and the interaction of them was detected by co-immunoprecipitation. As a result, MEHP exposure could promote the occurrence and progression of steatosis and the secretion of chemokines and inflammatory factors in L02 cells. MEHP could also affect the expression and activation of FPR2 and the secretion of FPR2 ligands. In addition, the promotion effect of MEHP on the secretion of total cholesterol and interleukin 1β in L02 cells could be significantly inhibited by the FPR2 antagonist. We concluded that FPR2 might affect the promotion effect of MEHP on steatosis of L02 cells by mediating inflammatory response.

Imaging features and management of focal liver lesions

Notably, the number of incidentally detected focal liver lesions (FLLs) has increased dramatically in recent years due to the increased use of radiological imaging. The diagnosis of FLLs can be made through a well-documented medical history, physical examination, laboratory tests, and appropriate imaging methods. Although benign FLLs are more common than malignant ones in adults, even in patients with primary malignancy, accurate diagnosis of incidental FLLs is of utmost clinical significance. In clinical practice, FLLs are frequently evaluated non-invasively using ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI). Although US is a cost-effective and widely used imaging method, its diagnostic specificity and sensitivity for FLL characterization are limited. FLLs are primarily characterized by obtaining enhancement patterns through dynamic contrast-enhanced CT and MRI. MRI is a problem-solving method with high specificity and sensitivity, commonly used for the evaluation of FLLs that cannot be characterized by US or CT. Recent technical advancements in MRI, along with the use of hepatobiliary-specific MRI contrast agents, have significantly improved the success of FLL characterization and reduced unnecessary biopsies. The American College of Radiology (ACR) appropriateness criteria are evidence-based recommendations intended to assist clinicians in selecting the optimal imaging or treatment option for their patients. ACR Appropriateness Criteria Liver Lesion-Initial Characterization guideline provides recommendations for the imaging methods that should be used for the characterization of incidentally detected FLLs in various clinical scenarios. The American College of Gastroenterology (ACG) Clinical Guideline offers evidence-based recommendations for both the diagnosis and management of FLL. American Association for the Study of Liver Diseases (AASLD) Practice Guidance provides an approach to the diagnosis and management of patients with hepatocellular carcinoma. In this article, FLLs are reviewed with a comprehensive analysis of ACR Appropriateness Criteria, ACG Clinical Guideline, AASLD Practice Guidance, and current medical literature from peer-reviewed journals. The article includes a discussion of imaging methods used for the assessment of FLL, current recommended imaging techniques, innovations in liver imaging, contrast agents, imaging features of common nonmetastatic benign and malignant FLL, as well as current management recommendations.

Hepatic fat quantification in dual-layer computed tomography using a three-material decomposition algorithm

OBJECTIVES

The purpose of this study was to evaluate a three-material decomposition algorithm for hepatic fat quantification using a dual-layer computed tomography (DL-CT) and MRI as reference standard on a large patient cohort.

METHOD

A total of 104 patients were retrospectively included in our study, i.e., each patient had an MRI exam and a DL-CT exam in our institution within a maximum of 31 days. Four regions of interest (ROIs) were positioned blindly and similarly in the liver, by two independent readers on DL-CT and MRI images. For DL-CT exams, all imaging phases were included. Fat fraction agreement between CT and MRI was performed using intraclass correlation coefficients (ICC), determination coefficients R2, and Bland-Altman plots. Diagnostic performance was determined using sensitivity, specificity, and positive and negative predictive values. The cutoff for steatosis was 5%.

RESULTS

Correlation between MRI and CT data was excellent for all perfusion phases with ICC calculated at 0.99 for each phase. Determination coefficients R2 were also good for all perfusion phases (about 0.95 for all phases). Performance of DL-CT in the diagnosis of hepatic steatosis was good with sensitivity between 89 and 91% and specificity ranging from 75 to 80%, depending on the perfusion phase. The positive predictive value was ranging from 78 to 93% and the negative predictive value from 82 to 86%.

CONCLUSION

Multi-material decomposition in DL-CT allows quantification of hepatic fat fraction with a good correlation to MRI data.

CLINICAL RELEVANCE STATEMENT

The use of DL-CT allows for detection of hepatic steatosis. This is especially interesting as an opportunistic finding CT performed for other reasons, as early detection can help prevent or slowdown the development of liver metabolic disease.

KEY POINTS

• Hepatic fat fractions provided by the dual-layer CT algorithm is strongly correlated with that measured on MRI. • Dual-layer CT is accurate to detect hepatic steatosis ≥ 5%. • Dual-layer CT allows opportunistic detection of steatosis, on CT scan performed for various indications.

Ultrasonography of Hepatocellular Carcinoma: From Diagnosis to Prognosis

Hepatocellular carcinoma (HCC) is a prominent contributor to cancer-related mortality worldwide. Early detection and diagnosis of liver cancer can significantly improve its prognosis and patient survival. Ultrasound technology, serving has undergone substantial advances as the primary method of HCC surveillance and has broadened its scope in recent years for effective management of HCC. This article is a comprehensive overview of ultrasound technology in the treatment of HCC, encompassing early detection, diagnosis, staging, treatment evaluation, and prognostic assessment. In addition, the authors summarized the application of contrast-enhanced ultrasound in the diagnosis of HCC and assessment of prognosis. Finally, the authors discussed further directions in this field by emphasizing overcoming existing obstacles and integrating cutting-edge technologies.

Clinical research of fibroscan ‒ TE-CAP at noninvasive diagnosis of hepatic steatosis in children

BACKGROUND & AIMS

The authors assess the diagnostic accuracy of the Transient Elastography-Controlled Attenuation Parameter (TE-CAP) in children of Southern China.

METHODS

105 obese or overweight children and adolescents were enrolled in the diagnostic test of TE-CAP assessment of hepatic steatosis using MRI-PDFF. Hepatic steatosis grades S0-S3 were classified. Statistical correlation, agreement and consistency between methods were evaluated. The diagnostic efficiency of TE-CAP was evaluated. The authors used the cutoff value of TE-CAP to detect hepatic steatosis in another 356 children.

RESULTS

The Area Under Curve (AUC) of TE-CAP for grade ≥ S1, ≥ S2, and ≥ S3 steatosis were 0.975, 0.984, and 0.997, respectively. For detecting ≥ S1 steatosis, TE-CAP had a sensitivity of 96 % and a specificity of 97 %. For detecting ≥ S2 steatosis, TE-CAP had a sensitivity of 97 % and a specificity of 93 %. For detecting ≥ S3 steatosis, TE-CAP had a sensitivity of 1 and a specificity of 94 %. TE-CAP and MRI-PDFF had a linear correlation (r = 0. 0.87, p < 0.001). The hepatic steatosis was identified in 40.2 % (143/356) of children in which the obesity and overweight were 69.8 % (113/162) and 40.0 % (18/45).

CONCLUSION

TE-CAP showed excellent diagnostic accuracy in pediatric hepatic steatosis.

Deep-learning segmentation to select liver parenchyma for categorizing hepatic steatosis on multinational chest CT

Unenhanced CT scans exhibit high specificity in detecting moderate-to-severe hepatic steatosis. Even though many CTs are scanned from health screening and various diagnostic contexts, their potential for hepatic steatosis detection has largely remained unexplored. The accuracy of previous methodologies has been limited by the inclusion of non-parenchymal liver regions. To overcome this limitation, we present a novel deep-learning (DL) based method tailored for the automatic selection of parenchymal portions in CT images. This innovative method automatically delineates circular regions for effectively detecting hepatic steatosis. We use 1,014 multinational CT images to develop a DL model for segmenting liver and selecting the parenchymal regions. The results demonstrate outstanding performance in both tasks. By excluding non-parenchymal portions, our DL-based method surpasses previous limitations, achieving radiologist-level accuracy in liver attenuation measurements and hepatic steatosis detection. To ensure the reproducibility, we have openly shared 1014 annotated CT images and the DL system codes. Our novel research contributes to the refinement the automated detection methodologies of hepatic steatosis on CT images, enhancing the accuracy and efficiency of healthcare screening processes.

Diagnostic performance of the GGT/HDL-C ratio for NAFLD in adults with obesity undergoing bariatric surgery

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has become the most frequent liver disease, closely related with metabolic risk factors such as obesity, insulin resistance, dyslipidemia, diabetes mellitus, and metabolic syndrome. In this context, γ-Glutamyl transpeptidase (GGT) and high-density lipoprotein cholesterol (HDL-C) have shown correlations with steatosis severity and metabolic syndrome, respectively. This positions the GGT/HDL-C ratio as a potential diagnostic indicator for NAFLD.

OBJECTIVE

To assess the diagnostic performance of the GGT/HDL-C ratio for NAFLD in adults with obesity undergoing bariatric surgery.

METHODS

We conducted an analytical cross-sectional study, designed as a diagnostic test evaluation. A secondary database of 249 adults with obesity was analyzed. The optimal cut-off point was ascertained using three methodologies, and five adjustment models were constructed for the total population, further stratified by sex.

RESULTS

The optimal cut-off point was 20.5 U/mmol and the AUC of the ratio was 0.81 (95% CI: 0.64-0.98), with sensitivity and specificity being 82.5% and 77.8%, respectively. In the overall group with an elevated GGT/HDL-C ratio, the prevalence of NAFLD increased by 14% (PR: 1.14; 95% CI: 1.04-1.33). Specifically, women displaying this altered ratio showed a 19% increased prevalence (PR: 1.19; 95% CI: 1.07-1.42) compared to those with normal values.

CONCLUSIONS

The GGT/HDL-C ratio is a promising biomarker for the diagnosis of NAFLD in an adult population living with obesity.

Remission of Nonalcoholic Fatty Liver Disease After Radical Surgery in Patients with Colorectal Cancer: A Single-Center Retrospective Study

Purpose: The purpose of this study was to investigate the relationship between remission of nonalcoholic fatty liver disease (NAFLD) and radical surgery for colorectal cancer (CRC) patients. Methods: From January 2014 to December 2021, data of patients with concurrent CRC and NAFLD who underwent radical surgery in a single-center hospital were retrospectively collected. NAFLD was defined as a mean computed tomography (CT) liver attenuation value of <40 Hounsfield units (HUs). Comparison of preoperative and 1-year postoperative CT images was performed to evaluate the change of NAFLD. Multivariate logistic regression analysis was performed to identify independent predictive factors for NAFLD remission. The Kaplan-Meier method was used to estimate overall survival (OS) and disease-free survival (DFS) between the remission group and no remission group. Results: In this study, a total of 55 eligible patients were included. The remission group had 33 (60.0%) patients and the no remission group had 22 (40.0%) patients. The mean preoperative weight was 66.1 ± 9.9 kg. The mean preoperative body mass index (BMI) was 25.4 ± 2.5 kg/m2. We found that the average weight was significantly decreased (P < 0.01), average BMI was significantly decreased (P < 0.01), and HU score was significantly increased (P < 0.01). By comparing baseline characteristics between the remission group and no remission group, we found that the remission group exhibited larger tumor sizes (P = 0.036) than the no remission group. In the multivariate logistic regression analysis, we found that weight change was a predictor for NAFLD (odds ratio = 0.764, 95% confidence interval = 0.618-0.944, P = 0.013). We did not find any statistically significant differences in OS (P = 0.182) or DFS (P = 0.248) between the remission group and no remission group. Conclusions: The NAFLD remission rate reached 60.0% for CRC patients 1 year after radical surgery. In addition, we found that weight change was a predictor of NAFLD remission.

Kidney and liver fat accumulation: from imaging to clinical consequences

BACKGROUND

Recent studies indicate that accumulation of adipose tissue in various organs such as liver and kidney may contribute to the pathophysiology of metabolic syndrome. We aim to investigate the association between kidney and liver adipose tissue accumulation, assessed by the magnetic resonance imaging (MRI) proton density fat fraction technique, along with its relation to clinical and biochemical parameters.

METHODS

We included 51 volunteers with phenotypical features of metabolic syndrome (mean age = 34 years, mean body-mass index = 26.4 kg/m2) in our study in which liver and kidney adipose tissue accumulation was assessed via MRI-proton density fat fraction along with multiple other clinical and biochemical parameters such as estimated glomerular filtration rate (eGFR), urine albumin-to-creatinine ratio, serum lipid profile, liver function tests and body-mass index (BMI).

RESULTS

Our results from the univariate linear regression analysis indicate that both the kidney and liver scores were positively correlated with markers such as BMI, urine albumin-to-creatinine ratio, triglycerides (p < 0.001) and negatively correlated with eGFR (p < 0.05). In multivariate analysis, urine albumin-to-creatinine ratio (p < 0.05), triglycerides (p < 0.01), eGFR (p < 0.05) and BMI (p < 0.001) were found to be independently associated with kidney and liver fat accumulation, respectively (R2 = 0.64; R2 = 0.89). There was also a positive correlation between kidney and liver fat accumulation.

CONCLUSION

We have found a significant association between adipose tissue accumulation in liver and kidney and the parameters of metabolic syndrome. Moreover, the presence of a strong association between kidney and liver fat accumulation and kidney function parameters such as urine albumin-to-creatinine ratio and eGFR may be an indicator of the clinical significance of parenchymal fat accumulation.

Clinical correlates of CT imaging-derived phenotypes among lean and overweight patients with hepatic steatosis

The objective of this study is to define CT imaging derived phenotypes for patients with hepatic steatosis, a common metabolic liver condition, and determine its association with patient data from a medical biobank. There is a need to further characterize hepatic steatosis in lean patients, as its epidemiology may differ from that in overweight patients. A deep learning method determined the spleen-hepatic attenuation difference (SHAD) in Hounsfield Units (HU) on abdominal CT scans as a quantitative measure of hepatic steatosis. The patient cohort was stratified by BMI with a threshold of 25 kg/m2 and hepatic steatosis with threshold SHAD ≥  - 1 HU or liver mean attenuation ≤ 40 HU. Patient characteristics, diagnoses, and laboratory results representing metabolism and liver function were investigated. A phenome-wide association study (PheWAS) was performed for the statistical interaction between SHAD and the binary characteristic LEAN. The cohort contained 8914 patients-lean patients with (N = 278, 3.1%) and without (N = 1867, 20.9%) steatosis, and overweight patients with (N = 1863, 20.9%) and without (N = 4906, 55.0%) steatosis. Among all lean patients, those with steatosis had increased rates of cardiovascular disease (41.7 vs 27.8%), hypertension (86.7 vs 49.8%), and type 2 diabetes mellitus (29.1 vs 15.7%) (all p < 0.0001). Ten phenotypes were significant in the PheWAS, including chronic kidney disease, renal failure, and cardiovascular disease. Hepatic steatosis was found to be associated with cardiovascular, kidney, and metabolic conditions, separate from overweight BMI.

Non-invasive hepatic fat quantification: Can multi-echo Dixon help?

Objective

To evaluate the diagnostic accuracy of multi-echo Dixon magnetic resonance imaging (MRI) in hepatic fat quantification, in comparison with that of magnetic resonance spectroscopy (MRS), on 3.0-T MRI.

Materials and Methods

Fifty-five adults with no known liver disease underwent MRI in a 3.0-T scanner for determination of the hepatic fat fraction, with two techniques: multi-echo Dixon, in a manually drawn region of interest (ROI) and in the entire liver parenchyma (automated segmentation); and MRS. The diagnostic accuracy and cutoff value for multi-echo Dixon were determined, with MRS being used as the reference standard.

Results

The mean fat fraction obtained by multi-echo Dixon in the manually drawn ROI and in the entire liver was 5.2 ± 5.8% and 6.6 ± 5.2%, respectively, whereas the mean hepatic fat fraction obtained by MRS was 5.7 ± 6.4%. A very strong positive correlation and good agreement were observed between MRS and multi-echo Dixon, for the ROI (r = 0.988, r2 = 0.978, p < 0.001) and for the entire liver parenchyma (r = 0.960, r2 = 0.922, p < 0.001). A moderate positive correlation was observed between the hepatic fat fraction and body mass index of the participants, regardless of the fat estimation technique employed.

Conclusion

For hepatic fat quantification, multi-echo Dixon MRI demonstrated a very strong positive correlation and good agreement with MRS (often considered the gold-standard noninvasive technique). Because multi-echo Dixon MRI is more readily available than is MRS, it can be used as a rapid tool for hepatic fat quantification, especially when the hepatic fat distribution is not homogeneous.

Perilipin2 inhibits the replication of hepatitis B virus deoxyribonucleic acid by regulating autophagy under high-fat conditions

BACKGROUND

Chronic hepatitis B virus (HBV) infection is often associated with increased lipid deposition in hepatocytes. However, when combined with non-alcoholic fatty liver disease or hyperlipidemia, it tends to have a lower HBV deoxyribonucleic acid (DNA) load. The relationship between lipid metabolism and HBV DNA replication and its underlying mechanisms are not well understood.

AIM

To investigate the relationship between lipid metabolism and HBV DNA replication and its underlying mechanisms.

METHODS

1603 HBsAg-seropositive patients were included in the study. We first explored the relationship between patients' lipid levels, hepatic steatosis, and HBV DNA load. Also, we constructed an HBV infection combined with a hepatic steatosis cell model in vitro by fatty acid stimulation of HepG2.2.15 cells to validate the effect of lipid metabolism on HBV DNA replication in vitro. By knocking down and overexpressing Plin2, we observed whether Plin2 regulates autophagy and HBV replication. By inhibiting both Plin2 and cellular autophagy under high lipid stimulation, we examined whether the Plin2-autophagy pathway regulates HBV replication.

RESULTS

The results revealed that serum triglyceride levels, high-density lipoprotein levels, and hepatic steatosis ratio were significantly lower in the HBV-DNA high load group. Logistic regression analysis indicated that hepatic steatosis and serum triglyceride levels were negatively correlated with HBV-DNA load. Stratified analysis by HBeAg showed significant negative correlations between HBV-DNA load and hepatic steatosis ratio in both HBeAg-positive and HBeAg-negative groups. An in vitro cell model was developed by stimulating HepG2.2.15 cells with palmitic acid and oleic acid to study the relationship between HBV-DNA load and lipid metabolism. The results of the in vitro experiments suggested that fatty acid treatment increased lipid droplet deposition and decreased the expression of cell supernatant HBsAg, HBeAg, and HBV DNA load. Western blot and polymerase chain reaction analysis showed that fatty acid stimulation significantly induced Plin2 protein expression and inhibited the expression of hepatocyte autophagy proteins. Inhibition of Plin2 protein expression under fatty acid stimulation reversed the reduction in HBsAg and HBeAg expression and HBV DNA load induced by fatty acid stimulation and the inhibition of cellular autophagy. Knocking down Plin2 and blocking autophagy with 3-methyladenine (3-MA) inhibited HBV DNA replication.

CONCLUSION

In conclusion, lipid metabolism is a significant factor affecting HBV load in patients with HBV infection. The in vitro experiments established that fatty acid stimulation inhibits HBV replication via the Plin2-autophagy pathway.

MiRNAs in Alcohol-Related Liver Diseases and Hepatocellular Carcinoma: A Step toward New Therapeutic Approaches?

Alcohol-related Liver Disease (ALD) is the primary cause of chronic liver disorders and hepatocellular carcinoma (HCC) development in developed countries and thus represents a major public health concern. Unfortunately, few therapeutic options are available for ALD and HCC, except liver transplantation or tumor resection for HCC. Deciphering the molecular mechanisms underlying the development of these diseases is therefore of major importance to identify early biomarkers and to design efficient therapeutic options. Increasing evidence indicate that epigenetic alterations play a central role in the development of ALD and HCC. Among them, microRNA importantly contribute to the development of this disease by controlling the expression of several genes involved in hepatic metabolism, inflammation, fibrosis, and carcinogenesis at the post-transcriptional level. In this review, we discuss the current knowledge about miRNAs' functions in the different stages of ALD and their role in the progression toward carcinogenesis. We highlight that each stage of ALD is associated with deregulated miRNAs involved in hepatic carcinogenesis, and thus represent HCC-priming miRNAs. By using in silico approaches, we have uncovered new miRNAs potentially involved in HCC. Finally, we discuss the therapeutic potential of targeting miRNAs for the treatment of these diseases.

The use of bicarbonate-sulphate-calcium-magnesium and sodium-low drinkable water improves functional gastrointestinal symptoms in patients with non-alcoholic fatty liver disease: A prospective study

BACKGROUND & AIMS

Non-alcoholic fatty liver disease is increasingly gaining epidemiological ground in liver diseases. Among the proposed non-pharmacologic interventions, dietary interventions have been widely used. Several patients suffering from it complain of gastrointestinal symptoms unrelated to organic gastrointestinal tract disease. However, the role of drinking water quality modifications in this regard has not been investigated in depth.

METHODS

Patients with upper or lower functional gastrointestinal symptoms were enrolled and divided into groups based on bright liver ultrasound relief's presence (SP) or absence (NSP). These patients were asked to drink bicarbonate-sulphate-calcium-magnesium and sodium-low drinkable water (Fonte Essenziale ®) for six months. Participants were assessed at baseline (T0), at the end of six months of drinking water intake (T6), and after an additional six months of washout (T12) by questionnaires designed to evaluate lower and upper gastrointestinal symptoms (Leeds dyspepsia score, short form) severity and frequency.

RESULTS

A total of 61 patients were enrolled. In the SP population, the severity of lower gastrointestinal symptoms improved between T0-T6 (Z: -2.437; ES: 0.312) and worsened after the water washout (Z: -2.492; ES: 0.319). The same was for the Leeds score severity sub score in T0-T6 (Z: -2.850; ES: 0.364) and T6-T12 (Z: -2.921; ES: 0.374). These improvements seem unrelated to the severity of liver steatosis at baseline. Furthermore, no safety issues were recorded while taking the water nor during the six-month follow-up afterwards.

CONCLUSION

Regular six-month intake of 400 mL of Fonte Essenziale® water was associated, in the absence of dietary regimen modifications, with an improvement in some qualitative and quantitative features of upper and lower functional gastrointestinal symptoms in both an SP and NSP sample.

Oxidative Stress-Induced Liver Damage and Remodeling of the Liver Vasculature

As an organ critically important for targeting and clearing viruses, bacteria, and other foreign material, the liver operates via immune-tolerant, anti-inflammatory mechanisms indispensable to the immune response. Stress and stress-induced factors disrupt the homeostatic balance in the liver, inflicting tissue damage, injury, and remodeling. These factors include oxidative stress (OS) induced by viral infections, environmental toxins, drugs, alcohol, and diet. A recurrent theme seen among stressors common to multiple liver diseases is the induction of mitochondrial dysfunction, increased reactive oxygen species expression, and depletion of ATP. Inflammatory signaling additionally exacerbates the condition, generating a proinflammatory, immunosuppressive microenvironment and activation of apoptotic and necrotic mechanisms that disrupt the integrity of liver morphology. These pathways initiate signaling pathways that significantly contribute to the development of liver steatosis, inflammation, fibrosis, cirrhosis, and liver cancers. In addition, hypoxia and OS directly enhance angiogenesis and lymphangiogenesis in chronic liver diseases. Late-stage consequences of these conditions often narrow the outcomes for liver transplantation or result in death. This review provides a detailed perspective on various stress-induced factors and the specific focus on role of OS in different liver diseases with special emphasis on different molecular mechanisms. It also highlights how resultant changes in the liver vasculature correlate with pathogenesis.

Liver Cell Type-Specific Targeting by Nanoformulations for Therapeutic Applications

Hepatocytes exert pivotal roles in metabolism, protein synthesis and detoxification. Non-parenchymal liver cells (NPCs), largely comprising macrophages, dendritic cells, hepatic stellate cells and liver sinusoidal cells (LSECs), serve to induce immunological tolerance. Therefore, the liver is an important target for therapeutic approaches, in case of both (inflammatory) metabolic diseases and immunological disorders. This review aims to summarize current preclinical nanodrug-based approaches for the treatment of liver disorders. So far, nano-vaccines that aim to induce hepatitis virus-specific immune responses and nanoformulated adjuvants to overcome the default tolerogenic state of liver NPCs for the treatment of chronic hepatitis have been tested. Moreover, liver cancer may be treated using nanodrugs which specifically target and kill tumor cells. Alternatively, nanodrugs may target and reprogram or deplete immunosuppressive cells of the tumor microenvironment, such as tumor-associated macrophages. Here, combination therapies have been demonstrated to yield synergistic effects. In the case of autoimmune hepatitis and other inflammatory liver diseases, anti-inflammatory agents can be encapsulated into nanoparticles to dampen inflammatory processes specifically in the liver. Finally, the tolerance-promoting activity especially of LSECs has been exploited to induce antigen-specific tolerance for the treatment of allergic and autoimmune diseases.

Novel insights and mechanisms of diet-induced obesity: Mid-term versus long-term effects on hepatic transcriptome and antioxidant capacity in Sprague-Dawley rats

AIMS

The study of molecular mechanisms related to obesity and associated pathologies like type 2-diabetes and non-alcoholic fatty liver disease requires animal experimental models in which the type of obesogenic diet and length of the experimental period to induce obesity deeply affect the metabolic alterations. Therefore, this study aimed to test the influence of aging along a rat model of diet-induced obesity in gene expression of the hepatic transcriptome.

MAIN METHODS

A high-fat/high-fructose diet to induce obesity was used. Mid- (13 weeks) and long-term (21 weeks) periods were established. Caloric intake, bodyweight, hepatic fat, fatty acid profile, histological changes, antioxidant activity, and complete transcriptome were analyzed.

KEY FINDINGS

Excess bodyweight, hepatic steatosis and altered lipid histology, modifications in liver antioxidant activity, and dysregulated expression of transcripts related to cell structure, glucose & lipid metabolism, antioxidant & detoxifying capacity were found. Modifications in obese and control rats were accounted for by the different lengths of the experimental period studied.

SIGNIFICANCE

Main mechanisms of hepatic fat accumulation were de novo lipogenesis or altered fatty acid catabolism for mid- or long-term study, respectively. Therefore, the choice of obesity-induction length is a key factor in the model of obesity used as a control for each specific experimental design.

Correlation between CT Abdominal Anthropometric Measurements and Liver Density in Individuals with Non-Alcoholic Fatty Liver Disease

Background: With a growing frequency, nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease worldwide. NAFLD has a strong correlation with other metabolic disorders, such as obesity, particularly abdominal obesity, even though the underlying causes or risk factors are not entirely understood. This study aims to investigate correlations between abdominal anthropometric measurements and the presence and intensity of liver steatosis as assessed by unenhanced computed tomography (CT). Methods: One hundred and nineteen patients (male/female, 66/53; mean age 54.54 +/− 12.90 years) underwent abdominal non–contrast-enhanced CT. CT images were examined to determine the attenuation of liver parenchyma, subcutaneous fat depth, and waist circumference (WC). Results: Among all patients, WC (r = −0.78, p < 0.0001), infraumbilical subcutaneous fat thicknesses (r = −0.51, p < 0.0001), right paraumbilical subcutaneous fat thicknesses (r = −0.62, p < 0.0001), and left paraumbilical subcutaneous fat thicknesses (r = −0.53, p < 0.0001) had a high inverse correlation with the liver attenuation values. The presence of T2D (OR: 2.40, p = 0.04), WC (OR: 11.45, p < 0.001), right paraumbilical (OR: 10.09, p < 0.001), left paraumbilical (OR: 2.81, p = 0.01), and infraumbilical (OR: 3.06, p = 0.007) were strongly independent predictors of NAFLD risk. Moreover, regarding the laboratory parameters, only the higher value of GGT (OR: 2.84, p = 0.009) is a predictor of NAFLD risk. Conclusions: Our data show that higher baseline values of all abdominal anthropometric measurements are correlated with liver attenuation and act as predictors of NAFLD risk.

The association between steatosis and liver damage in transfusion-dependent beta thalassaemia patients

Non-alcoholic fatty liver disease (NAFLD) is a global health problem. Iron is the leading cause of liver damage in patients with transfusion-dependent thalassaemia (TDT), and data on the contribution of NAFLD to liver damage in TDT is lacking. Forty-five heavily transfused TDT patients who did not have biochemical or ultrasonic evidence of liver cirrhosis were evaluated for effects of iron overload, including the presence of diabetes mellitus, hypogonadism, serum ferritin, R2-MRI-liver, and liver enzymes alanine aminotransferase and aspartate aminotransferase. Liver fibrosis and steatosis were estimated using transient elastography (TE). Nine (20%) patients had significant steatosis (S1), and their body mass index (BMI) and liver fibrosis scores were higher than in patients without significant steatosis (S0) (p = 0.03 and p = 0.004, respectively). On regression analysis, the controlled attenuation parameter (CAP) score (i.e., degree of liver steatosis) was associated only with increasing BMI. The TE score (i.e., degree of liver fibrosis) was associated with increasing age, CAP score, male gender, and presence of diabetes. Neither liver steatosis nor fibrosis showed significant association with the liver iron concentration or iron-related organ damage (hypogonadism). In this cohort of TDT patients, steatosis of the liver, which is associated with increasing BMI, appeared to increase the risk of liver fibrosis.

Correlation between the Severity of Metabolic Dysfunction-Associated Fatty Liver Disease and Serum Uric Acid to Serum Creatinine Ratio

PURPOSE

As one of the most common chronic liver diseases, metabolic dysfunction-associated fatty liver disease (MAFLD) had different prognoses between mild and moderate-severe levels. Serum uric acid to serum creatinine ratio (sUA/Cr) can reflect the overall metabolic status of the body. To explore a convenient indicator to screen MAFLD and distinguish the severity of the disease, this study analyzed the correlation between sUA/Cr and the severity of MAFLD.

METHODS

228 participants were enrolled and divided into 2 groups, including mild MAFLD and non-MAFLD group and moderate-severe MAFLD group, based on liver/spleen computed tomography (CT) ratios. The correlations between sUA/Cr and the severity of MAFLD were analyzed by logistic and linear regression. Receiver operating characteristics (ROCs) analyzed the predictive ability of sUA/Cr for the severity of MAFLD expressed by the area under curve (AUC).

RESULTS

The level of sUA/Cr was higher in themoderate-severe MAFLD group than mild MAFLD and non-MAFLD group (6.14 ± 1.55 vs. 5.51 ± 1.19, P = 0.008). After adjustment for confounders, the correlation analysis showed that patients with elevated sUA/Cr had a higher risk of moderate-severe MAFLD (OR: 1.350, P = 0.036). A higher sUA/Cr level was associated with lower liver CT values (β = -0.133, P = 0.039) and liver/spleen CT ratio (β = -0.154, P = 0.016). sUA/Cr had the ability to discriminate the severity of MAFLD (AUC: 0.623).

CONCLUSION

sUA/Cr was positively associated with the risk of moderate-severe MAFLD and had the predictive ability to discriminate the moderate-severe MAFLD from mild MAFLD and non-MAFLD. The sUA/Cr level was suggested to be monitored and controlled in the screening and treatment of MAFLD.

Updates on Quantitative MRI of Diffuse Liver Disease: A Narrative Review

Diffuse liver diseases are highly prevalent conditions around the world, including pathological liver changes that occur when hepatocytes are damaged and liver function declines, often leading to a chronic condition. In the last years, Magnetic Resonance Imaging (MRI) is reaching an important role in the study of diffuse liver diseases moving from qualitative to quantitative assessment of liver parenchyma. In fact, this can allow noninvasive accurate and standardized assessment of diffuse liver diseases and can represent a concrete alternative to biopsy which represents the current reference standard. MRI approach already tested for other pathologies include diffusion-weighted imaging (DWI) and radiomics, able to quantify different aspects of diffuse liver disease. New emerging MRI quantitative methods include MR elastography (MRE) for the quantification of the hepatic stiffness in cirrhotic patients, dedicated gradient multiecho sequences for the assessment of hepatic fat storage, and iron overload. Thus, the aim of this review is to give an overview of the technical principles and clinical application of new quantitative MRI techniques for the evaluation of diffuse liver disease.

Exome-wide association analysis of CT imaging-derived hepatic fat in a medical biobank

Nonalcoholic fatty liver disease is common and highly heritable. Genetic studies of hepatic fat have not sufficiently addressed non-European and rare variants. In a medical biobank, we quantitate hepatic fat from clinical computed tomography (CT) scans via deep learning in 10,283 participants with whole-exome sequences available. We conduct exome-wide associations of single variants and rare predicted loss-of-function (pLOF) variants with CT-based hepatic fat and perform cross-modality replication in the UK Biobank (UKB) by linking whole-exome sequences to MRI-based hepatic fat. We confirm single variants previously associated with hepatic fat and identify several additional variants, including two (FGD5 H600Y and CITED2 S198_G199del) that replicated in UKB. A burden of rare pLOF variants in LMF2 is associated with increased hepatic fat and replicates in UKB. Quantitative phenotypes generated from clinical imaging studies and intersected with genomic data in medical biobanks have the potential to identify molecular pathways associated with human traits and disease.

De novo non-alcoholic fatty liver disease after pancreatectomy: A systematic review

BACKGROUND

As operative techniques and mortality rates of pancreatectomy have improved, there has been a shift in focus to maintaining and improving the nutritional status of these patients as we continue to learn more about post-operative complications. Although pancreatic endocrine and exocrine insufficiencies are known complications of pancreatectomy, increased longevity of these patients has also led to a higher incidence of de novo fatty liver disease which differs from traditional fatty liver disease given the lack of metabolic syndrome.

AIM

To identify and summarize patterns and risk factors of post-pancreatectomy de novo fatty liver disease to guide future management.

METHODS

We performed a database search on PubMed selecting papers published between 2001 and 2022 in the English language. PubMed was last accessed 1 June 2022.

RESULTS

Various factors influence the development of de novo fatty liver including indication for surgery (benign vs malignant), type of pancreatectomy, amount of pancreas remnant, and peri-operative nutritional status. With an incidence rate up to 75%, de novo non-alcoholic fatty liver disease (NAFLD) can develop within 12 mo after pancreatectomy and various risk factors have been established including pancreatic resection line and remnant pancreas volume, peri-operative malnutrition and weight loss, pancreatic exocrine insufficiency (EPI), malignancy as the indication for surgery, and postmenopausal status.

CONCLUSION

Since majority of risk factors leads to EPI and malnutrition, peri-operative focus on nutrition and enzymes replacement is key in preventing and treating de novo NAFLD after pancreatectomy.

Regression of Graft Steatosis After Liver Transplantation

Introduction: Liver grafts with limited steatosis are currently used for liver transplantation, but the natural history of graft steatosis is not well known. Project Aims or Questions: This program evaluation aimed at assessing changes of steatosis after liver transplantation. Design: A retrospective chart review was performed assessing presence and severity of steatosis in the liver explant and in time zero donor graft biopsies carried out at the time-point of liver transplantation on histopathology and on imaging one year thereafter in 30 well characterized patients. Results: Ten patients (33%) showed steatosis on explant. Time zero biopsy revealed steatosis in 18 grafts (60%) and no steatosis in 12 (40%). One year after transplantation, 8 patients (27%) had steatosis and 22 patients (63%) had none. Fourteen patients (47%) showed changes in steatosis: 12 showed resolution and 2 showed de novo steatosis. Explant macrovesicular steatosis was associated with presence of steatosis 1 year after transplantation (binary logistic regression model, p = 0.014), but not macrovesicular steatosis in the donor graft at time-point of transplantation. Conclusion: Resolution of graft steatosis was frequent. Presence of steatosis in the recipient's liver, but not graft steatosis, was a risk factor for steatosis 1 year after transplantation. Factors related to the recipient seem to prevail over donor-related factors in determining the persistence or de novo appearance of steatosis after liver transplantation.

Hepatic steatosis with mass effect: A case report

BACKGROUND

Hepatic steatosis is a common radiologic finding. Some imaging inklings are the absence of a mass effect, and there is currently no report of hepatic steatosis with mass effect.

CASE SUMMARY

A 23-year-old female was admitted due to a liver mass for half a month. No obvious abnormalities were found in physical and laboratory examinations. Ultrasound, computed tomography, and magnetic resonance imaging showed a huge mass between the liver and stomach with a significant mass effect, and the caudate lobe and left lobe of the liver were involved. The signal on T2- and T1- weighted fat-saturated images of the mass was significantly reduced, and the enhanced scan showed inhomogeneous enhancement. Surgical and pathological findings indicated the diagnosis of hepatic steatosis. The operation and re-review of the patient's images showed that the lesion was supplied by the branch of the hepatic artery. The signal on T1-weighted out-of-phase images of the lesion was lower than on in-phase images, and there was no black rim cancellation artifact around the hepatic steatosis area on T1-weighted out-of-phase images. The dynamic enhancement pattern of the lesion was similar to that of the adjacent normal liver parenchyma. The above characteristics suggested that the lesion was hepatic steatosis. However, in this case, the lesion showed exogenous growth and was mass-like, with an obvious mass effect, which has not been reported previously.

CONCLUSION

Hepatic steatosis could grow exogenously and has an obvious mass effect. It needs to be distinguished from fat-rich tumors. The T1-weighted in- and out-of-phase images and dynamic enhanced scanning are valuable for differential diagnosis of this lesion.

Unraveling the Complexity of Liver Disease One Cell at a Time

The human liver is a complex organ made up of multiple specialized cell types that carry out key physiological functions. An incomplete understanding of liver biology limits our ability to develop therapeutics to prevent chronic liver diseases, liver cancers, and death as a result of organ failure. Recently, single-cell modalities have expanded our understanding of the cellular phenotypic heterogeneity and intercellular cross-talk in liver health and disease. This review summarizes these findings and looks forward to highlighting new avenues for the application of single-cell genomics to unravel unknown pathogenic pathways and disease mechanisms for the development of new therapeutics targeting liver pathology. As these technologies mature, their integration into clinical data analysis will aid in patient stratification and in developing treatment plans for patients suffering from liver disease.

Just Drink a Glass of Water? Effects of Bicarbonate–Sulfate–Calcium–Magnesium Water on the Gut–Liver Axis

Background and Aim: Fonte Essenziale® water is a bicarbonate–sulfate–calcium–magnesium water, low in sodium, recognized by the Italian health care system in hydropinotherapy and hepatobiliary dyspepsia therapy. We wanted to explore its effects on the gut–liver axis and microbiota in non-alcoholic fatty liver disease patients.

Patients and Methods: We considered enrollment for 70 patients, of which four were excluded. We finally enrolled 55 patients with ultrasound-documented steatosis (SPs+) and 11 patients without it (SPs−). They then drank 400 ml of water for 6 months in the morning on an empty stomach. Routine hematochemical and metabolic parameters, oxidative stress parameters, gastrointestinal hormone levels, and fecal parameters of the gut microbiota were evaluated at three different assessment times, at baseline (T0), after 6 months (T6), and after a further 6 months of water washout (T12). We lost, in follow-up, 4 (T6) and 22 (T12) patients.

Results: Between T0–T6, we observed a significant Futuin A and Selenoprotein A decrease and a GLP-1 and PYY increase in SPs+ and the same for Futuin A and GLP-1 in SPs−. Effects were lost at T12. In SPs+, between T0–T12 and T6–12, a significant reduction in Blautia was observed; between T0–T12, a reduction of Collinsella unc. was observed; and between T0–T12 and T6–12, an increase in Subdoligranulum and Dorea was observed. None of the bacterial strains we analyzed varied significantly in the SPs− population.

Conclusion: These results indicate beneficial effects of water on gastrointestinal hormones and hence on the gut–liver axis in the period in which subjects drank water both in SPs− and in SPs+.

Fat-only Dixon: how to use it in body MRI

The Dixon method for fat/water separation is widely used to obtain uniform fat suppression using the water-only reconstruction. However, the fat-only reconstruction is potentially neglected in clinical practice, either not sent to the PACS or ignored upon imaging review. Fat-only Dixon provides a valuable tool for rapid screening for microscopic fat and problem-solving of lesions of interest. This work will review the physics of Dixon fat/water separation, some clinical applications, artifacts, and protocol design considerations of Dixon imaging, and how to integrate the Dixon method into the clinical practice of body MRI.

A New SteatoScore in the Evaluation of Non-Alcoholic Liver Disease in Oncologic Patients

Purpose

The aims of this study were to evaluate the reproducibility of a new multi-parametric steatoscore (new SteatoScore) in oncologic patients with non-alcoholic fatty liver disease (NAFLD) and to compare it with computed tomography (CT).

Materials and Methods

Fifty-one (31 men, 20 women) oncologic patients, with a mean age and weight of 63.9 years and 78.33 kg, respectively, were retrospectively enrolled in the study. Patients underwent ultrasound (US) and computed tomography (CT) examinations as part of their oncologic follow-up protocol. US examinations were performed by using a 3.5-MHz convex probe. During the US examination, three standardized clips were obtained in each patient. Two operators performed all measurements, one of whom repeated the processing twice in 1 year. Hepatic/renal ratio (HR), attenuation rate (AR), diaphragm visualization (DV), hepatic/portal vein ratio (HPV), and portal vein wall visualization (PVW) were acquired and calculated by using Matlab and inserted in a multi-parametric algorithm called new SteatoScore. On unenhanced CT scan, hepatic attenuation (HA), liver-spleen difference (L-S), and liver/spleen ratio (L/S) were measured by placement of a region of interest (ROI) within liver and spleen parenchyma, avoiding areas with vessels and biliary ducts.

Results

The intra-observer variability was greater than the inter-observer one, with intraclass correlation coefficient (ICC) values of 0.94 and 0.97, respectively. Correlation between single US and CT parameters provided an agreement in no case exceeding 50%. New SteatoScore showed high reproducibility, and high coefficient of correlation with L-S (R = -0.64; p < 0.0001) and L/S (R = -0.62; p < 0.0001) at CT.

Conclusion

New SteatoScore has a high reproducibility and shows a good correlation with unenhanced CT in evaluation of oncologic patients with NAFLD.

Chemotherapy-Induced Liver Injury in Patients with Colorectal Liver Metastases: Findings from MR Imaging

Chemotherapy-induced liver injury has been found to be quite common in cancer patients undergoing chemotherapy. Being aware of chemotherapy-induced hepatotoxicity is important for avoiding errors in detecting liver metastases and for defining the most appropriate clinical management strategy. MRI imaging has proven to be a useful troubleshooting tool that helps overcome false negatives in tumor response imaging after chemotherapy due to liver parenchyma changes. The purpose of this review is, therefore, to describe the characteristics of magnetic resonance imaging of the broad spectrum of liver damage induced by systemic chemotherapeutic agents in order to avoid misdiagnoses of liver metastases and disease progression and to define the most appropriate clinical management strategy.

Deciphering the toxicological role of Porphyromonas gingivalis derived endotoxins in liver diseases

Periodontitis is a most prevalent and infectious multifactorial inflammatory disease and is characterized by the progressive destruction of the tooth-supporting tissues. Porphyromonas gingivalis, a Gram‑negative oral anaerobe, mainly causes periodontitis and it is one of the most important risk factors responsible for aggravation of existing systemic diseases. Several experimental and clinical studies have shown the positive association between periodontitis and different forms of liver disease. Periodontal diseases increase the prevalence of non-alcoholic fatty liver diseases and cirrhosis. Infected periodontium and pathogens in the periodontal microenvironments release pathogen-associated molecular patterns such as peptidoglycan, lipopolysaccharides, gingipain, fimbria, bacterial DNA, etc, and damage-associated molecular patterns such as interleukins-1α, β, - 8, and galectin-3, etc. These virulence factors and cytokines enter the bloodstream, disseminate into the whole body, and induce a variety of systemic pathological effects, including liver diseases (steatosis and fibrosis). Maintaining oral hygiene by scaling and root planning significantly improves liver damage in patients with periodontitis. Dentists and physicians should have more awareness in understanding the bidirectional nature of the relationship between oral and systemic diseases. Importantly, periodontitis condition aggravates simple fatty liver into fibrotic disease and therefore, the aim of this review is to understand the possible link between periodontitis and liver diseases.

Correlation of Hepatic Steatosis Among Cohabitants Using Hounsfield Unit From Coronary Computed Tomography

Background

Individuals living in the same household are exposed to common risk factors. We hypothesized that living with someone who has fatty liver disease increases the risk of having the same disease.

Methods

This was a retrospective study that included pairs of men and women who shared the same residential addresses, underwent screening non-contrast computed tomography for coronary calcium scoring and had Hounsfield Unit density for liver and spleen in the field of view available for measurement. The primary goal was to determine the association between hepatic steatosis and living in the same household. Secondary end-points compared to body mass index, triglyceride levels, type 2 diabetes mellitus (T2DM) and hypertension.

Results

Out of 1,362 cohabitant pairs, there were 202 couples with either the male or female having hepatic steatosis and 10 cohabitant pairs with both the male and female having hepatic steatosis. In 1,150 cohabitant pairs out of 1,362, neither man nor woman had hepatic steatosis. Pearson correlation coefficient (r) for hepatic steatosis between cohabitant pairs was 0.122 (p-value: < 0.001), suggesting that no correlation was found. Elevated triglyceride levels were prevalent among cohabitant pairs with hepatic steatosis, when compared to pairs without hepatic steatosis (p-value < 0.05). Female gender and having a diagnosis of hepatic steatosis also showed a strong association with higher body mass index, T2DM and hypertension (p-value < 0.05).

Conclusion

Despite the assumption of exposure to similar environmental factors, our results did not show any correlation of hepatic steatosis among the cohabitants.

Relationship between Quantitative Sonographic Measurements and Serum Biochemical Parameters in Childhood Obesity

PURPOSE

We investigated the relationship between sonographic measurements of fatty liver and body mass index standard deviation score (BMI-Z score), abdominal wall fat thickness (AWFT), and serum biochemical parameters in childhood obesity.

METHODS

Anthropometric, laboratory, and ultrasonography data were obtained from 174 children with BMI-Z score >1. After the qualitative grading of hepatosteatosis (grades 0-3), the quantitative liver-kidney echogenicity ratio (LKER) was calculated using a software tool. Groups according to sex, age (AG-I to AG-III), BMI-Z score (BMG-I to BMG-III), and hepatosteatosis degree (HS-I and HS-II) were formed. The differences and distributions of the variables were statistically analyzed and compared among the groups.

RESULTS

Serum transaminase and glucose levels showed a positive correlation with LKER, whereas the HDL level showed a negative correlation. BMI-Z score and AWFT showed a positive correlation with fasting insulin level and HOMA-IR value. LKER was significantly higher in girls than in boys (p=0.008). In the AG-I group (age 3-8.9 years), the BMI-Z score was significantly higher, whereas AWFT was significantly lower than in the other age groups (p<0.001). The cutoff point of LKER for predicting grade 2 or higher steatosis (HS-II group) was determined to be 1.83. Cardiovascular disease risk was significantly higher in the HS-II group (p=0.035).

CONCLUSION

As a valuable quantitative measurement tool, LKER can be used for the sonographic screening of fatty liver. AWFT, on the basis of its correlation with fasting insulin level and HOMA-IR value, may be a useful sonographic parameter in the management of childhood obesity.

The feasibility of T2 mapping in the assessment of hepatic steatosis, inflammation, and fibrosis in patients with non-alcoholic fatty liver disease: a preliminary study

AIM

To determine the feasibility of magnetic resonance imaging T2 mapping in the quantification of liver steatosis in patients with biopsy-proven non-alcoholic fatty liver disease (NAFLD), and to assess the effect of inflammation and fibrosis on T2 values of the liver.

MATERIAL AND METHODS

Twenty-three consecutive patients with biopsy-proven NAFLD who underwent T2 mapping between December 2013 and September 2014 were included in this study. All patients underwent fast spin echo multi-echo sequence with eight echoes for T2 measurements.

RESULTS

The mean liver T2 value and percentage of histological steatosis was 64.9 ± 7.4 ms and 46.5 ± 27.6%, respectively. There was a good correlation between the liver T2 value and histology-determined steatosis (r = 0.780, p<0.001) and grade of steatosis (r_s = 0.779, p<0.001). The mean T2 value in patients with definitive non-alcoholic steatohepatitis (NASH) was significantly higher in comparison with patients without NASH (69 ± 7.37 versus 61.73 ± 5.99 ms, p=0.016). The correlation between T2 value and NAFLD activity score (NAS) was significant (r_s = 0.443, p=0.034); however, the correlation disappeared after adjustment for hepatic steatosis and fibrosis (r=0.131, p=0.572). There was a close inverse correlation between T2 value and fibrosis stage after adjusting for hepatic steatosis (r=-0.536, p=0.012).

CONCLUSION

T2 mapping can be used for quantification of hepatic steatosis, as there is a close correlation between T2 relaxation values and histology-determined steatosis. Patients with definite NASH have increased T2 values and there is an inverse correlation between the T2 value and fibrosis stage of the liver. T2 mapping in NAFLD may be a useful clinical tool for disease assessment and prognostication.

Can Dual-energy CT-based Virtual Monoenergetic Imaging Improve the Assessment of Hypodense Liver Metastases in Patients With Hepatic Steatosis?

RATIONALE AND OBJECTIVES

To evaluate the impact of noise-optimized virtual monoenergetic imaging (VMI) on lesion demarcation and measuring accuracy of hypoattenuating liver metastases in patients with fatty liver disease compared to standard reconstructions.

MATERIALS AND METHODS

Twenty-eight patients (mean age 62.2 ± 7.7 years) with fatty liver disease and hypoattenuating liver metastases who underwent unenhanced and contrast-enhanced portal-venous dual-energy CT (DECT) were enrolled. Standard linearly blended and VMI series were reconstructed in 10-keV intervals. Lesion-to-parenchyma contrast-to-noise ratio (CNR) was calculated and the best VMI series was further investigated in a subjective evaluation of overall image quality and lesion demarcation. Size measurements were performed independently by measuring all hypodense lesions (n = 58) twice in a predefined sequence. Inter- and intra-rater agreement was assessed using intra-class correlation coefficient (ICC) statistics.

RESULTS

The calculated CNR was greatest at 40-keV VMI (4.3 ± 2.6), significantly higher compared to standard reconstructions (2.9 ± 1.9; p < 0.001). Subjective ratings for overall image quality showed no significant difference between the 2 reconstruction techniques (both medians 4; p = 0.147), while lesion margin demarcation was found to be superior for 40-keV VMI (median 5; p ≤ 0.001). Inter- (ICC, 0.98 for 40-keV VMI; ICC, 0.93 for standard reconstruction) and intra-rater (ICC, 0.99 for 40-keV VMI; ICC, 0.94 for standard image series) analysis showed an excellent agreement for lesion measurements in both reconstruction techniques.

CONCLUSION

Noise-optimized VMI reconstructions significantly improve contrast and lesion demarcation of hypoattenuating liver metastases in patients with the fatty liver disease compared to standard reconstruction.

PAR2 promotes high-fat diet-induced hepatic steatosis by inhibiting AMPK-mediated autophagy

Protease-activated receptor 2 (PAR2) is a member of G protein-coupled receptors. There are two types of PAR2 signaling pathways: Canonical G-protein signaling and β-arrestin signaling. Although PAR2 signaling has been reported to aggravate hepatic steatosis, the exact mechanism is still unclear, and the role of PAR2 in autophagy remains unknown. In this study, we investigated the regulatory role of PAR2 in autophagy during high-fat diet (HFD)-induced hepatic steatosis in mice. Increased protein levels of PAR2 and β-arrestin-2 and their interactions were detected after four months of HFD. To further investigate the role of PAR2, male and female wild-type (WT) and PAR2-knockout (PAR2 KO) mice were fed HFD. PAR2 deficiency protected HFD-induced hepatic steatosis in male mice, but not in female mice. Interestingly, PAR2-deficient liver showed increased AMP-activated protein kinase (AMPK) activation with decreased interaction between Ca²⁺/calmodulin-dependent protein kinase kinase β (CAMKKβ) and β-arrestin-2. In addition, PAR2 deficiency up-regulated autophagy in the liver. To elucidate whether PAR2 plays a role in the regulation of autophagy and lipid accumulation in vitro, PAR2 was overexpressed in HepG2 cells. Overexpression of PAR2 decreased AMPK activation with increased interaction of CAMKKβ with β-arrestin-2 and significantly inhibited autophagic responses in HepG2 cells. Inhibition of autophagy by PAR2 overexpression further exacerbated palmitate-induced lipid accumulation in HepG2 cells. Collectively, these findings suggest that the increase in the PAR2-β-arrestin-2-CAMKKβ complex by HFD inhibits AMPK-mediated autophagy, leading to the alleviation of hepatic steatosis.