Quantification of hepatic steatosis: a comparison of computed tomography and magnetic resonance indices in candidates for living liver donation

Testosterone therapy reduces hepatic steatosis in men with type 2 diabetes and low serum testosterone concentrations

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is highly prevalent in people with diabetes with no available treatment.

AIM

To explore the effect of testosterone treatment on liver. Testosterone therapy improves insulin resistance and reduces total body fat, but its impact on the liver remains poorly studied.

METHODS

This secondary analysis of a 40 wk, randomised, double-blinded, placebo-controlled trial of intramuscular testosterone undecanoate in men with type 2 diabetes and lowered serum testosterone concentrations evaluated the change in hepatic steatosis as measured by liver fat fraction on magnetic resonance imaging (MRI).

RESULTS

Of 88 patients enrolled in the index study, 39 had liver MRIs of whom 20 received testosterone therapy and 19 received placebo. All patients had > 5% hepatic steatosis at baseline and 38 of 39 patients met diagnostic criteria for NAFLD. Median liver fat at baseline was 15.0% (IQR 11.5%-21.1%) in the testosterone and 18.4% (15.0%-28.9%) in the placebo group. Median ALT was 34units/L (26-38) in the testosterone and 32units/L (25-52) in the placebo group. At week 40, patients receiving testosterone had a median reduction in absolute liver fat of 3.5% (IQR 2.9%-6.4%) compared with an increase of 1.2% in the placebo arm (between-group difference 4.7% P < 0.001). After controlling for baseline liver fat, testosterone therapy was associated with a relative reduction in liver fat of 38.3% (95% confidence interval 25.4%-49.0%, P < 0.001).

CONCLUSION

Testosterone therapy was associated with a reduction in hepatic steatosis in men with diabetes and low serum testosterone. Future randomised studies of testosterone therapy in men with NAFLD focusing on liver-related endpoints are therefore justified.

Quantitative MRI Assessment of Pancreatic Steatosis Using Proton Density Fat Fraction in Pediatric Obesity

Objective

To assess the feasibility of quantitatively assessing pancreatic steatosis using magnetic resonance imaging (MRI) and its correlation with obesity and metabolic risk factors in pediatric patients.

Materials and Methods

Pediatric patients (≤ 18 years) who underwent liver fat quantification MRI between January 2016 and June 2019 were retrospectively included and divided into the obesity and control groups. Pancreatic proton density fat fraction (P-PDFF) was measured as the average value for three circular regions of interest (ROIs) drawn in the pancreatic head, body, and tail. Age, weight, laboratory results, and mean liver MRI values including liver PDFF (L-PDFF), stiffness on MR elastography, and T2^* values were assessed for their correlation with P-PDFF using linear regression analysis. The associations between P-PDFF and metabolic risk factors, including obesity, hypertension, diabetes mellitus (DM), and dyslipidemia, were assessed using logistic regression analysis.

Results

A total of 172 patients (male:female = 125:47; mean ± standard deviation [SD], 13.2 ± 3.1 years) were included. The mean P-PDFF was significantly higher in the obesity group than in the control group (mean ± SD, 4.2 ± 2.5% vs. 3.4 ± 2.4%; p = 0.037). L-PDFF and liver stiffness values showed no significant correlation with P-PDFF (p = 0.235 and p = 0.567, respectively). P-PDFF was significantly associated with obesity (odds ratio 1.146, 95% confidence interval 1.006–1.307, p = 0.041), but there was no significant association with hypertension, DM, and dyslipidemia.

Conclusion

MRI can be used to quantitatively measure pancreatic steatosis in children. P-PDFF is significantly associated with obesity in pediatric patients.

The Mexican consensus on alcoholic hepatitis

Alcoholic hepatitis is a frequent condition in the Mexican population. It is characterized by acute-on-chronic liver failure, important systemic inflammatory response, and multiple organ failure. The severe variant of the disease implies elevated mortality. Therefore, the Asociación Mexicana de Gastroenterología and the Asociación Mexicana de Hepatología brought together a multidisciplinary team of health professionals to formulate the first Mexican consensus on alcoholic hepatitis, carried out utilizing the Delphi method and resulting in 37 recommendations. Alcohol-related liver disease covers a broad spectrum of pathologies that includes steatosis, steatohepatitis, different grades of fibrosis, and cirrhosis and its complications. Severe alcoholic hepatitis is defined by a modified Maddrey's discriminant function score ≥ 32 or by a Model for End-Stage Liver Disease (MELD) score equal to or above 21. There is currently no specific biomarker for its diagnosis. Leukocytosis with neutrophilia, hyperbilirubinemia (> 3 mg/dL), AST > 50 U/l (< 400 U/l), and an AST/ALT ratio > 1.5-2 can guide the diagnosis. Abstinence from alcohol, together with nutritional support, is the cornerstone of treatment. Steroids are indicated for severe disease and have been effective in reducing the 28-day mortality rate. At present, liver transplantation is the only life-saving option for patients that are nonresponders to steroids. Certain drugs, such as N-acetylcysteine, granulocyte-colony stimulating factor, and metadoxine, can be adjuvant therapies with a positive impact on patient survival.

Alcohol associated liver disease 2020: A clinical practice guideline by the Italian Association for the Study of the Liver (AISF)

Alcohol use disorder which includes alcohol abuse and dependence represents one of the leading risk factors for premature mortality in Europe and it is responsible of over 200 conditions, including neuropsychiatric disorders, chronic diseases, cancers and accidents leading to permanent disability. Alcohol use disorder represents the most common cause of liver damage in the Western world, with a wide spectrum of diseases ranging from steatosis, steatohepatitis, fibrosis, cirrhosis and cancer. The present clinical practice guidelines by the Italian Association for the Study of the Liver (AISF) are focused on the current knowledge about epidemiology, pathophysiology, clinical features, diagnosis and treatment of alcohol associated liver disease, aiming to provide practical recommendations on the management of this complex pathological condition.

Computed Tomography Measurements of Hepatic Steatosis in Cholelitihiasis and Cholecystectomy Cases Using Unenhanced Images

INTRODUCTION

Computed tomography (CT) measurements of hepatic steatosis can be performed using unenhanced CT images. The purpose of this study was to assess the occurrence of hepatic steatosis using unenhanced CT images for patients undergoing cholecystectomy or having cholelithiasis.

METHODS

A total of 143 unenhanced CT cases from a single centre were retrospectively examined. The CT number of liver, ratio of CT number of liver to spleen, and CT number of liver minus CT number of spleen were measured in three groups: (1) patients undergoing cholecystectomy, (2) patients having cholelithiasis, and (3) control group. Abdominal circumference, anterior subcutaneous fat tissue thickness, and body mass index were obtained.

RESULTS

Mean CT number of liver was significantly different between the group of patients with cholecystectomy and cholelithiasis and the control group (P < .001) and also between cases of cholecystectomy and cholelithiasis (P = .041), with the lowest CT number of liver in the cholecystectomy group. The mean CT number of liver minus CT number of spleen and mean CT number (liver/spleen) ratios, evaluated separately for both lobes, were not different comparing the cholelithiasis and cholecystectomy groups. The mean CT number of liver minus CT number of spleen and mean CT number (liver/spleen) ratios differed significantly between the control group and both patient groups (P < .001). Positive correlations were identified between abdominal circumference, subcutaneous fat depth, body mass index, and liver size and hepatic steatosis.

CONCLUSION

There was an increased occurrence of hepatic steatosis in patients who have undergone a cholecystectomy compared with patients treated for cholelithiasis and the control group.

Computed Tomography Findings as a Novel Predictor of Alcohol-Associated Hepatitis Outcomes

BACKGROUND

Accurate prediction of outcomes for alcohol-associated hepatitis (AH) is critical, as prognosis determines treatment eligibility. Computed tomography (CT) features may provide prognostic information beyond traditional models.

AIMS

Our aim was to identify CT features that predict outcomes in AH.

METHODS

We studied 108 patients retrospectively with definite or probable AH, who underwent admission abdominal CT. A radiologist blinded to outcome evaluated eight CT features. The primary outcome was 90-day mortality.

RESULTS

Twenty-five (23.2%) patients died within 90 days. While traditional prognostic tools, including Maddrey discriminant function (DF), predicted 90-day mortality (OR 1.01 [1.00, 1.03], P = 0.02), abdominal CT findings were also accurate predictors. On abdominal CT, patients with severe AH had larger volume of ascites (moderate/large volume: 34.0 vs. 8.2%, P < 0.0001), longer liver length (17.1 vs. 15.1 cm, P = 0.001), greater liver heterogeneity (moderate/severe: 21.3 vs. 8.2%, P = 0.007), and more likely to have splenomegaly (42.6 vs. 18.0%, P = 0.009) than those with mild AH. Univariate analysis revealed that ascites volume (OR 2.59 [1.35, 4.96], P = 0.004) predicted 90-day mortality. In multivariate analysis, degree of ascites predicted 90-day mortality when controlling for Maddrey DF (OR 2.36 [1.19, 4.69], P = 0.01) and trended toward significance when controlling for MELD score (OR 2.02 [0.95, 4.30], P = 0.07).

CONCLUSION

CT findings in AH differentiate disease severity and predict 90-day mortality; therefore, the role of CT warrants further investigation as a tool in AH management.

Quantification of Hepatic Lipid Using 7.0T Proton Magnetic Resonance Spectroscopy and Computed Tomography in Mild Alcoholic Steatotic Mice

BACKGROUND

In vivo proton magnetic resonance spectroscopy (1H MRS) has been used to semi-quantify hepatic lipids in preclinical and clinical studies of fatty liver disease. Quantifying absolute amount of liver lipids utilizing 1H MRS and computerized tomography (CT) is essential to accurately interpret hepatic steatosis.

PURPOSE

To establish reliable parameters to convert relative hepatic lipid levels obtained by 1H-MRS and liver volumes by CT to the absolute amount of liver lipids in a mild hepatic steatosis, and to determinate the correlation between these absolute liver lipids with liver triglyceride (TG) and cholesterol (Chol) measured by biochemistry assays.

METHODS

Mild steatosis was induced in mice by a 3 week ethanol diet containing standard lipids. Evaporated liver water was measured after baking liver tissues and volume of liver was measured using water displacement. 1H MRS semiquantitation of hepatic lipids and CT measurement of liver volume were performed and then used to calculate amount of liver lipids. These data were compared with liver TG and Chol.

RESULTS

Percentage of liver water and liver density were persistent in two groups and were used to convert the percentage of liver lipids to liver water by 1H-MRS to the absolute amount of liver lipids per gram of liver or per milliliter of CT volume. Using 1H-MRS and biochemical assays, an increase of liver lipids was confirmed in mild steatosis mice compared to controls (P<0.01). The amounts of imaging detected liver lipids were strongly correlated to liver TG and Chol measured by biochemical assays in mild steatosis mice.

CONCLUSION

1H MRS and CT liver imaging techniques are able to quantify absolute hepatic lipid levels utilizing relative persistent parameters percentage of liver water and liver density in a preclinical mild steatosis setting.

Comparison of CT and magnetic resonance mDIXON-Quant sequence in the diagnosis of mild hepatic steatosis

OBJECTIVE:

To determine the diagnostic performance of CT in the assessment of mild hepatic steatosis by comparison with MR mDIXON-Quant as a reference standard, and to explore their clinical applications.

METHODS:

In this prospective study 169 volunteers were included. Each subject underwent CT and MR mDIXON-Quant examinations. Hepatic steatosis evaluations were performed via liver attenuation alone (CT L), liver to spleen attenuation ratio (CT L/S), difference between liver and spleen attenuation (CT L-S), and MR mDIXON-Quant imaging. The effectiveness of CT L, CT L/S, and CT L-S in diagnosing hepatic steatosis severity of ≥5%, ≥10%, and ≥15% was compared, using mDIXON-Quant results as standard.

RESULTS:

65 subjects exhibited mild hepatic steatosis. Hepatic steatosis measurement with mDIXON-Quant was strongly correlated with the three CT methods. Using cutoff value, the sensitivity and specificity of diagnosing hepatic steatosis ≥5, ≥10, and ≥15% were 64.6, 91.3, 100%, and 90.4, 89.7, 93.0% for CT L; 50.8, 87.0, 100%, and 96.2, 98.6, 97.5% for CT L/S; and 67.7, 87.0, 100%, and 81.7, 98.6, 97.5% for CT L-S, respectively. ROC analysis indicated that 58.9, 56.5, and 52.8 HU for CT L; 1.06, 0.98, and 0.90 HU for CT L/S; and 6.21,-1.04, and -4.93 HU for CT L-S were cutoff values for diagnosing hepatic steatosis ≥5%,≥10%, and ≥15%, respectively.

CONCLUSIONS:

The three CT methods exhibit better agreements with mDIXON-Quant imaging for diagnosing hepatic steatosis ≥10%. Hence, CT and mDIXON-Quant could serve as suitable tools for the accurate quantification of mild hepatic steatosis.

SIGNIFICANT FINDS OF THE STUDY:

The close agreement between the three different CT methods (based on our cutoff values) and mDIXON-Quant imaging suggests that CT could accurately diagnose hepatic steatosis ≥10%. Thus, CT and mDIXON-Quant imaging can accurately measure mild hepatic steatosis.

WHAT THIS STUDY ADDS:

Only few studies have compared hepatic steatosis quantification between CT and mDIXON-Quant. We are the first to determine the diagnostic performance of unenhanced CT for quantitatively assessing mild hepatic steatosis, in reference to magnetic resonance mDIXON-Quant imaging.

Liver volume is a prognostic indicator for clinical outcome of patients with alcoholic hepatitis

PURPOSE

To evaluate the prognostic value of abdominal computed tomography (CT) in patients with alcoholic hepatitis (AH).

METHODS

This ancillary study was based on data collected during a previous randomized controlled trial in patients with AH. Clinical response was defined as the improvement of the baseline MELD score ≥3 points at 3 months. All patients underwent contrast-enhanced CT of the abdomen. The following parameters were measured: (1) liver density, spleen density, and liver-to-spleen density ratio; (2) liver-to-body weight (LBW) ratio; and (3) subcutaneous fat, visceral fat, and muscular content. Improvers and non-improvers were compared with univariate, multivariate, and ROC analyses. Results were compared with a validation cohort of patients.

RESULTS

Fifty-eight patients (mean age, 56 years) were analyzed, including 34 (59 %) improvers. On multivariate analysis, LBW ratio (OR = 3.73; 95 % CI, 1.65-8.46; p = 0.002) and subcutaneous fat (OR = 1.01; 95 % CI, 1.00-1.02; p = 0.022) were associated with clinical response, with AUROC curves of 0.78 ± 0.06 (p < 0.001) and 0.66 ± 0.07 (p = 0.043), respectively. LBW ≥2.4 % predicted response with 88 % sensitivity and 63 % specificity. In the validation cohort (n = 42, 64 % improvers), the same cut-off value predicted response with 93 % sensitivity and 60 % specificity.

CONCLUSIONS

In patients suffering from AH, the liver volume appears to be a major positive prognostic factor.

Predictive Value of Unenhanced Computerized Tomography for Detecting Hepatosteatosis in Living Liver Donors

OBJECTIVE

Macrovesicular hepatosteatosis is related to post-transplantation complications, so preoperative hepatosteatosis determination plays a critical role in donor selection. The aim of this study was to evaluate the efficacy of unenhanced computerized tomography (CT) in determining hepatosteatosis in liver donor candidates.

METHODS

Information about donor candidates was retrospectively reviewed. In this screening, 27 donor candidates who underwent liver biopsy because of suspected hepatosteatosis in routine abdominal CT examination before transplantation, were reviewed. Liver biopsies and CT images were reevaluated by an experienced pathologist and radiologist. Macrovesicular hepatosteatosis was graded according to percentage and divided into 3 groups. Three radiologic liver attenuation indices were used: 1) hepatic attenuation value (CT(L)); 2) the difference between hepatic attenuation and spleen attenuation (CT(L-S)); and 3) the ratio of hepatic attenuation to splenic attenuation (CT(L/S)).

RESULTS

CT(L), CT(L-S), and CT(L/S) values of donors with hepatosteatosis were significantly higher than the donors without hepatosteatosis. In receiver operating characteristic analysis, the optimal cutoff value of these indices for determining hepatosteatosis were; 42.5, -5, and 0.98, respectively. At these cutoff values, the sensitivity and specificity of these indices were calculated to be 80% and 75%, 93.3% and 83.3%, and 93.3% and 83.3%, respectively. There were no statistical differences between their diagnostic performances. When these 3 indices were used for detect significant hepatosteatosis (>20%) it was observed that hepatosteatosis of only one donor could not be determined whereas it was seen that specificity was decreased markedly.

CONCLUSIONS

Despite the high diagnostic yield of unenhanced CT, it is not suitable to use alone for assessment of hepatosteatosis in clinical practice.

Liver steatosis and the risk of albuminuria: the multi-ethnic study of atherosclerosis

OBJECTIVE

To measure association between hepatic fat and albuminuria (an early marker of renal injury) in individuals without diabetes or hypertension.

METHODS

2,281 individuals in the Multi-Ethnic Study of Atherosclerosis without diabetes or hypertension, renal disease, or excess alcohol consumption underwent computed tomography (CT) for assessment of liver attenuation (marker of hepatic lipid content) and urinalysis (for albuminuria) at initial study visit, with assessment of incident and prevalent albuminuria by logistic regression in follow-up.

RESULTS

After adjustment for age, gender, race, smoking, blood pressure, insulin resistance, and body mass index, individuals with less liver fat (higher liver CT attenuation) had a lower probability of having albuminuria at Exam 1 (OR per 10 unit increase in attenuation 0.77, 95 % CI 0.61-0.97, P = 0.02). At median 9.3 years follow-up, albuminuria was identified in 129 individuals were (5.8 %). In fully adjusted models (with age, smoking, body mass index, blood pressure, diabetes and hypertension as time-dependent covariates), lower liver attenuation (greater liver fat) was associated with higher risk of incident albuminuria (OR 0.79, 95 % CI 0.66-0.94, P = 0.008).

CONCLUSIONS

Hepatic attenuation is associated with prevalent and incident albuminuria, an early, potent risk factor for renal risk in a population not clearly at risk for future renal failure.

Magnetic resonance fat quantification in living donor liver transplantation

OBJECTIVE

Hepatic steatosis can cause substantial problems for both donors and recipients in living donor liver transplantation (LDLT). The aim of this study is to evaluate the accuracy of the magnetic resonance IDEAL (iterative decomposition of water and fat with echo asymmetry and least squares estimation) sequence in quantifying the liver fat during LDLT.

MATERIALS AND METHODS

A total of 63 liver donors (29 men and 34 women ranging from 18 to 47 years old with a mean age of 30) who received both magnetic resonance imaging (MRI) and intraoperative liver biopsy were enrolled in this study. MR IDEAL IQ sequences were performed by 1.5-T MRI (Discovery 450; GE Healthcare, Milwaukee, Wis, United States) to estimate the liver fatty content. Accuracy was assessed through linear regression between fat fraction image and pathology grading. Sensitivity and specificity of MR IDEAL IQ fat fractions were also calculated.

RESULTS

A total of 63 LDLTs were performed and with pathology grading. No fatty content was found in 48 donors (76.2%; group 1), 5% to 10% fatty liver in 11 donors (17.4%; group 2), 11% to 15% fatty liver in 2 donors (3.2%; group 3), and >16% fatty change in 2 donors (3.2%; group 4). MR IDEAL fat fraction results were excellent in prediction of the normal and fatty content and with good correlation with the pathology grading (2.9 ± 0.9, 8.3 ± 4.2, P < .0001). Linear regression between IDEAL image and pathology grading indicated a high accuracy rate (R(2) = 0.813, R(2) = 0.9286) for all 4 groups. The sensitivity and specificity for detection of liver steatosis in MRI fat fraction image were 100% and 77.1% (P < .0001, 95% confidence interval 0.000-1.000).

CONCLUSION

MR IDEAL IQ sequencing is a highly precise and accurate method in quantifying hepatic steatosis for the living donor.