Measurement of liver stiffness as a non-invasive method for diagnosis of non-alcoholic fatty liver disease

How to Identify Advanced Nonalcoholic Fatty Liver Disease in the Primary Care Setting

Nonalcoholic fatty liver disease (NAFLD) affects 30 to 40% of the population globally and is increasingly considered the most common liver disease. Patients with type 2 diabetes, obesity, and cardiovascular diseases are at especially increased risk for NAFLD. Although most patients with NAFLD do not have progressive liver disease, some patients progress to cirrhosis, liver cancer, and liver mortality. Given the sheer number of patients with NAFLD, the burden of disease is enormous. Despite this large and increasing burden, identification of NAFLD patients at risk for progressive liver disease in the primary care and diabetology practice settings remains highly suboptimal. In this review, our aim is to summarize a stepwise approach to risk stratify patients with NAFLD which should help practitioners in their management of patients with NAFLD.

Efficacy and safety of saroglitazar in real‐world patients of non‐alcoholic fatty liver disease with or without diabetes including compensated cirrhosis: A tertiary care center experience

Background and Aim

Saroglitazar, a dual PPAR α/γ agonist, is useful in management of NAFLD and diabetic dyslipidemia. Here, we report the safety and efficacy of saroglitazar in NAFLD patients with or without diabetes including compensated cirrhosis.

Methods

Patients, started on saroglitazar 4 mg were prospectively evaluated for 52 weeks in a tertiary care center in Eastern India. Effectiveness was measured in terms of anthropometric measurements, fasting blood glucose, LFT, lipid profile, HbA1c, and elastography parameters (LSM and CAP) measured at baseline, 24, and 52 weeks. Adverse drug reactions were monitored.

Results

A total of 112 patients were enrolled in the study, of whom 63 patients were taken up for per-protocol analysis. Mean age was 49.11 ± 11.09 years and 46(73%) were male. Thirty-four (54%) were nondiabetic. Eleven patients had compensated cirrhosis. There was significant improvement of LSM from baseline (11.03 ± 7.19 kPa) to 24-week (9.29 ± 6.39 kPa) and 52-week (8.59 ± 6.35 kPa) values respectively (P < 0.001). Significant reduction was also seen in CAP values, ALT, AST, HbA1c, LDL, total cholesterol, and triglyceride values. There was no significant weight change along the study interval. Pruritus occurred in one patient who required treatment discontinuation and another patient had mild symptomatic loose motion.

Conclusions

Saroglitazar is effective and safe in improving biochemical parameters and LSM and CAP values irrespective of weight reduction. It may be used in compensated cirrhotics with close monitoring for side effects.

Diagnosis and Staging of Pediatric Non-Alcoholic Fatty Liver Disease: Is Classical Ultrasound the Answer?

The increased prevalence of non-alcoholic fatty liver disease (NAFLD) requires special attention in pediatric patients, as it manifests in them in a more severe and progressive way compared to adults. The implementation of the appropriate therapeutic interventions is determinant of the attempts to treat it. For that purpose, early diagnosis and staging of the disease is essential. The purpose of this review was to find and reveal the most appropriate diagnostic strategies and tools for diagnosis and staging of pediatric NAFLD/NASH based on their accuracy, safety and effectiveness. The methodology followed was that of the literature review. Particular emphasis was put on the recent bibliography. A comparative study of published articles about the diagnosis and management of pediatric NAFLD/NASH was also performed. In terms of diagnosis, the findings converged on the use of classical ultrasound. Ultrasound presented average sensitivity and specificity for diagnosing the disease in children, while in the adult population, sensitivity and specificity were significantly higher. Proton density fat fraction magnetic resonance imaging has been increasingly used for the diagnosis of steatosis in pediatric patients. Elastography is an effective tool for staging liver fibrosis and discriminating NASH from NAFLD in children. Even though liver biopsy is the gold standard, especially for NASH, it should be avoided for pediatric patients. Biochemical tests are less specific and less sensitive for the diagnosis of NAFLD, and some of them are of high cost. It seems that diagnostic imaging should be a first-line tool for the staging and monitoring pediatric NAFLD/NASH in order for appropriate interventions to be implanted in a timely way.

The association of adiponectin gene polymorphisms with susceptibility and progression of NAFLD in a cohort of Egyptian patients

Background

Several genetic polymorphisms have been proven to play a key role in the progression of non-alcoholic fatty liver disease (NAFLD) from simple steatosis to NASH with fibrosis. Our aim was to study the effect of single nucleotide polymorphisms (SNPs) in the adiponectin gene, namely rs266729 and rs3774261, on susceptibility to NAFLD and disease progression.

Results

There was a definitive association between polymorphisms of the studied SNPs and NAFLD. Among rs266729, CG was significantly higher among patients than controls showing increased risk for NAFLD (P<0.05). AA genotype of the rs3774261 variant was significantly lower in patients than in controls (P value< 0.001) while AG and GG genotypes were significantly higher in patients than in controls (P value<0.05); A allele was significantly higher among controls (P=0.019) which might have a protective effect. None of the variants correlated significantly with the degree of steatosis. Using multivariate regression analysis, there was no significant correlation with any of the independent risk factors to the degree of steatosis.

Conclusions

There was an association between polymorphisms of the studied SNPs of rs266729 and rs3774261 of the adiponectin gene and NAFLD.

Associations between Pre-Bariatric High-Sensitivity C-Reactive Protein and Post-Surgery Outcomes

Background: Obesity is a chronic inflammatory condition associated with increased circulating levels of C-reactive protein (CRP). Bariatric surgery has been reported to be effective in improving both inflammatory and liver status. Our aims were to elucidate the relationships between pre-surgery high sensitivity-CRP (hs-CRP) values and post-surgery weight loss and liver steatosis and fibrosis in patients with severe obesity undergoing Roux-en-Y gastric bypass. Methods: We conducted an observational prospective study on 90 individuals with morbid obesity, who underwent gastric bypass. Anthropometric indices, laboratory assessment (lipid panel, glycemic status, liver enzymes, and hs-CRP), liver stiffness and steatosis were evaluated at baseline and 6-months after surgery. Results: There was a significant post-surgery reduction in all the anthropometric variables, with an average weight loss of 33.93 ± 11.79 kg; the mean percentage of total weight loss (TWL) was 27.96 ± 6.43%. Liver elasticity was significantly reduced (from 6.1 ± 1.25 to 5.42 ± 1.52 kPa; p = 0.002), as well as liver aminotransferases, nonalcoholic fatty liver disease fibrosis score (NFS) and the grade of steatosis. Serum hs-CRP levels significantly reduced (from 9.26 ± 8.45 to 3.29 ± 4.41 mg/L; p < 0.001). The correlations between hs-CRP levels and liver fibrosis (elastography), steatosis (ultrasonography), fibrosis-4 index, NFS, and surgery success rate were not significant. Regression analyses showed that serum hs-CRP levels were not predictive of liver status and success rate after surgery in both unadjusted and adjusted models. Conclusions: In patients with morbid obesity, bariatric surgery caused a significant decrease in hs-CRP levels, liver stiffness and steatosis. Baseline hs-CRP values did not predict the weight-loss success rate and post-surgery liver status.

A novel rapid immunoassay of serum type IV collagen 7S for the diagnosis of fibrosis stage of nonalcoholic fatty liver diseases

AIM

Type IV collagen 7S (T4C7S) is a valuable biomarker for detecting liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). The conventional T4C7S measurement via radioimmunoassay (T4C7S RIA) has shortcomings of radioisotope usage and longer assay periods. We compared T4C7S RIA with a newly developed, fast T4C7S chemiluminescent enzyme immunoassay (T4C7S CLEIA) and examined the diagnostic accuracies of and correlation between the two techniques.

METHODS

We evaluated 170 biopsy-confirmed patients with NAFLD. T4C7S was measured via both T4C7S RIA and T4C7S CLEIA. The correlation between T4C7S RIA and T4C7S CLEIA was analyzed in 305 total serum samples via exploratory research and 47 validation samples. The diagnostic accuracies of T4C7S CLEIA and T4C7S RIA were compared in the sera of patients with NAFLD and test samples.

RESULTS

Sera T4C7S levels of T4C7S CLEIA and T4C7S RIA significantly correlated in patients' samples via exploratory (r = 0.914, P = 0.000) and validation (r = 0.929, P = 0.000) research. At a 10% coefficient, T4C7S CLEIA concentration was 0.26 ng/ml in the serum samples, indicating high accuracy at even low concentrations. T4C7S CLEIA revealed distinct changes between each stage and high sensitivity in detecting the F2 stage, indicating a higher sensitivity in detecting low fibrosis stages than T4C7S RIA in patients with NAFLD.

CONCLUSIONS

The T4C7S CLEIA correlated well with the T4C7S RIA. Favorably, the T4C7S CLEIA has a higher sensitivity and rapid measurement time and requires a small sample volume; thus, it is a promising and popular biomarker for fibrosis stage diagnosis in NAFLD.

Liver Stiffness Is Increased in Polycystic Ovary Syndrome and Related With Complement C1q/Tumor Necrosis Factor-Related Protein 3 Levels: A Point Shear Wave Elastography Study

ABSTRACT

Nonalcoholic fatty liver disease is very common in patients with polycystic ovary syndrome (PCOS). In patients with PCOS, the clinical use of liver stiffness (LS) and whether LS increases or decreases are still unclear. The purpose of this study was to determine the parameters related to LS and whether there is an increase in LS in patients with PCOS compared with healthy controls. Thirty-eight women diagnosed with PCOS according to Rotterdam criteria and 28 healthy age- and sex-matched controls were included in this study. In addition to routine follow-up parameters for all patients, serum homeostatic model assessment of insulin resistance (HOMA-IR) and complement C1q/tumor necrosis factor-related protein 3 (CTRP3) levels were measured, and point shear wave elastography was performed. Body mass index; waist circumference; systolic blood pressure; serum glucose, alanine aminotransferase, highly sensitive C-reactive protein, and dehydroepiandrosterone sulfate, testosterone, and HOMA-IR levels; and luteinizing hormone/follicle-stimulating hormone ratio were higher in PCOS group compared with healthy controls (P < 0.05). Serum CTRP3 levels were lower in patients with PCOS (P < 0.05). Liver stiffness value was significantly higher in PCOS group than healthy controls (P < 0.001). Positive correlation was found between LS and waist circumference as well as calcium, dehydroepiandrosterone sulfate, testosterone, and HOMA-IR levels (P < 0.05 for each one). Negative correlation was found between LS and CTRP (P < 0.01 for each one). In linear regression analysis, only CTRP3 level was found to be related to LS (P < 0.001 and β = 0.734). Liver stiffness value obtained by point shear wave elastography increases in patients with PCOS compared with healthy controls and is closely and negatively related to serum CTRP3 levels.

Open-label phase II study evaluating safety and efficacy of the non-steroidal farnesoid X receptor agonist PX-104 in non-alcoholic fatty liver disease

Background

The PX-104 is an oral non-steroidal agonist for the farnesoid X receptor (FXR), a key regulator of bile acid (BA), glucose and lipid homeostasis.

Aims and methods

This single center, proof of concept study evaluated the efficacy, safety and tolerability of PX-104 in non-diabetic NAFLD patients. 12 individuals were treated daily with 5 mg of PX-104 orally for 4 weeks. Serum liver enzymes, insulin sensitivity by clamp like index (CLIX) and hepatic fat by proton ¹H‑MRS, MRI-PDFF and CAP were assessed. Hepatic energy metabolism and Kupffer cell function were evaluated by phosphorus ³¹P‑MRS and superparamagnetic iron oxide MRI (SPIO-MRI). Other readouts included serum lipids and markers of BA metabolism/signaling besides fecal microbiome and BA analysis.

Results

A significant decrease in ALT (p = 0.027; 1‑tailed) and GGT (p = 0.019) was observed, without changes in serum alkaline phosphatase or serum lipids. Insulin sensitivity improved in 92% of patients (p = 0.02). However, hepatic steatosis measured by PDFF-MRI, ¹H‑MRS and CAP besides extended serum lipoprotein and BA profiles did not change. NADPH/γATP ratios at ³¹P‑MRS significantly decreased (p = 0.022) possibly reflecting reduced hepatic inflammatory stress, but SPIO-MRI remained unchanged. Reduced preponderance of Coriobacteriaceae (p = 0.036) correlated with a relative reduction of total fecal BAs. There were no serious adverse events but short intervals of cardiac arrhythmia recorded in 2 patients led to termination of the study.

Conclusion

The non-steroidal FXR agonist PX-104 improved insulin sensitivity and liver enzymes after 4 weeks of treatment in non-diabetic NAFLD patients. Changes in fecal BAs and gut microbiota deserve more extensive investigations.

Electronic supplementary material

The online version of this article (10.1007/s00508-020-01735-5) contains supplementary material, which is available to authorized users.

Transient hepatic elastography has the best performance to evaluate liver fibrosis in non-alcoholic fatty liver disease (NAFLD)

INTRODUCTION AND AIM

The gold-standard for fibrosis diagnosis in non-alcoholic fatty liver disease (NAFLD) is liver biopsy, despite its invasive approach, sampling limitations and variability among observers. The objective was to validate the performance of non-invasive methods (Fibroscan™; APRI, FIB4 and NAFLD score) comparing with liver biopsy in the evaluation of liver fibrosis in patients with NAFLD.

MATERIAL AND METHODS

NAFLD patients ≥18 years of age who were submitted to liver biopsy were included and evaluated at two reference tertiary hospitals in Brazil with transient hepatic elastography (THE) assessment through Fibroscan™, APRI, FIB4 and NAFLD scores were determined. Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values for the diagnosis of advanced fibrosis were calculated to evaluate the performance of these non-invasive methods in NAFLD patients, adopting liver biopsy as the gold standard.

RESULTS

A total of 104 patients were studied. At three different cutoff values (7.9, 8.7 and 9.6kPa) THE presented the highest sensitivity values (95%, 90% and 85% respectively), and the highest NPV (98%, 96.4% and 95.1% respectively) for the diagnosis of advanced fibrosis. It also presented the highest AUROC (0.87; CI 95% 0.78-0.97).

CONCLUSION

When compared to the gold standard, transient hepatic elastography presented the best performance for the diagnosis and exclusion of advanced fibrosis in patients with NAFLD, overcoming APRI, FIB4 and NAFLD score.

Diagnostic accuracy of combined biomarker measurements and vibration-controlled transient elastography (VCTE) for predicting fibrosis stage of non-alcoholic fatty liver disease

BACKGROUND

Numerous biomarkers have been developed for assessing the presence and severity of liver fibrosis associated with non-alcoholic fatty liver disease (NAFLD). Fibrosis can be assessed by liver stiffness measurement (LSM) using vibration-controlled transient elastography (VCTE). Here we examined whether diagnostic accuracy and applicability can be further improved by combining various biomarker measurements with LSM.

METHODS

A total of 278 patients with biopsy-confirmed Japanese NAFLD patients were enrolled. Area under the receiver operator characteristic curve (AUROC) was evaluated for obtaining the optimum interpretation criteria for LSM by VCTE and comparing various biomarkers alone and in combination with LSM.

RESULTS

Liver stiffness measurements including cases with interquartile range (IQR)/median (M) < 30% or LSM ≤ 7.1 kPa demonstrated high applicability (90% of patients with NAFLD) and accuracy (AUROC: 0.891) for predicting stage ≥ 3 fibrosis. For all biomarkers tested, the AUROC values for predicting stage ≥ 3 fibrosis were increased when combined with LSM [platelet count, 0.734 vs. 0.912; type-4 collagen 7s (T4C7s), 0.894 vs. 0.921; aspartate aminotransferase to alanine aminotransferase ratio (AST/ALT), 0.774 vs. 0.906; AST to platelet ratio index, 0.789 vs. 0.902; FIB-4 index, 0.828 vs. 0.922; NAFLD fibrosis score, 0.800 vs. 0.906; CA index-fibrosis, 0.884 vs. 0.913; FM-fibro index, 0.920 vs. 0.943; FIB-4 index + T4C7s, 0.901 vs. 0.930], demonstrating the advantage of concurrent LSM.

CONCLUSIONS

While VCTE has slightly limited applicability (90%) for patients with NAFLD, concurrent measurement with certain biomarkers (especially FM-fibro, T4C7s, and FIB-4) greatly improves the diagnostic accuracy.

Acoustic Radiation Force Impulse and Conventional Ultrasound in the Prediction of Cirrhosis Complicating Fatty Liver: Does Body Mass Index Independently Alter the Results?

We investigated whether ultrasound (US) could quantify steatosis and fibrosis in non-alcoholic fatty liver disease (NAFLD). Estimates of fat by gray-scale, hepatorenal index (HRI) and fibrosis by acoustic radiation force impulse (ARFI) were made using the interquartile range (IQR)/median for ARFI quality. Biopsy was the gold standard. US fat assessment correlated with histologic grade and predicted steatosis. HRI predicted steatosis but did not improve accuracy. ARFI of good quality was highly sensitive toward severe fibrosis. The median ARFI value depended linearly on body mass index (BMI). Poor quality ARFI data had higher histologic steatosis, leading to higher mean steatosis grades in rejected data (p = 0.018). The ARFI quality cut with IQR/median >0.15 or >0.3 excluded many more patients with severe steatosis versus normal, influenced by increasing BMI. By combining the baseline US with ARFI, patients can be concurrently diagnosed for steatosis and fibrosis, two of the key pathologies of NAFLD and non-alcoholic steatohepatitis (NASH). However, severe steatosis and high BMI may falsely alter ARFI results.

Practical Use of Transient Elastography in Screening for Nonalcoholic Steatohepatitis in a Japanese Population

Background and Aims: Fatty infiltration of liver may induce insulin resistance (IR), and a proportion of patients with nonalcoholic fatty liver disease (NAFLD) is diagnosed with nonalcoholic steatohepatitis. Transient elastography is gaining popularity as a means of non-invasively determining both liver stiffness (fibrosis level) and degree of fatty infiltration, expressed as controlled attenuation parameter (CAP) value. Methods: The aims of this study were to investigate the association between IR and level of fatty liver, and to identify the group at a greater risk of nonalcoholic steatohepatitis using transient elastography and other noninvasive fibrosis markers. A total of 169 patients without chronic hepatitis B and C were analyzed. Results: The CAP value was significantly associated with IR (HOMA-IR ≥2.5; AUROC = 0.81), and the optimal cut-off to discriminate IR was 264 dB/m. The liver stiffness measurement and aspartate aminotransferase-to-platelet ratio index values were significantly higher for CAP ≥264 than in CAP <264. The 9 patients among the overall 169 patients (5.3%) and among the 102 NAFLD patients (8.8%) who showed ≥264 dB and ≥7.0 kPa in transient elastography could represent good candidates for liver biopsy. Conclusions: Evaluation of NAFLD based on CAP values was useful in diagnosing IR. About 9% of NAFLD patients in a Japanese outpatient clinic with a few metabolic complications might be considered good candidates for liver biopsy to confirm nonalcoholic steatohepatitis.

Diagnosis and management of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in Western industrialised countries. The prevalence of NAFLD is increasing in parallel with the global rise in obesity and type 2 diabetes mellitus. NAFLD represents a spectrum of liver disease severity. NAFLD begins with accumulation of triacylglycerols in the liver (steatosis), and is defined by hepatic fatty infiltration amounting to greater than 5% by liver weight or the presence of over 5% of hepatocytes loaded with large fat vacuoles. In almost a quarter of affected individuals, steatosis progresses with the development of liver inflammation to non-alcoholic steatohepatitis (NASH). NASH is a potentially progressive liver condition and with ongoing liver injury and cell death can result in fibrosis. Progressive liver fibrosis may lead to the development of cirrhosis in a small proportion of patients. With the growing prevalence of NAFLD, there is an increasing need for a robust, accurate and non-invasive approach to diagnosing the different stages of this condition. This review will focus on (1) the biochemical tests and imaging techniques used to diagnose the different stages of NAFLD; and (2) a selection of the current management approaches focusing on lifestyle interventions and pharmacological therapies for NAFLD.

Long-term Results of Bariatric Surgery for Non-alcoholic Fatty Liver Disease/Non-alcoholic Steatohepatitis Treatment in Morbidly Obese Japanese Patients

BACKGROUND

Patients with morbid obesity are complicated with metabolic diseases and have a high incidence of non-alcoholic fatty liver disease (NAFLD), including non-alcoholic steatohepatitis (NASH).

METHODS

We report on a follow-up study of a cohort included 102 obese patients (55 males and 47 females, mean age 42.9 ± 10.6 years) undergoing bariatric surgery for the management of morbid obesity. Abdominal computed tomography was performed before and 1 year after surgery. Anthropometric and biochemical measurements were performed at 1, 3, and 5 years after surgery.

RESULTS

The mean body mass index (BMI) of the NAFLD patients improved from 42.5 ± 8.3 kg/m2 to 28.5 ± 6.9, and 29.1 ± 5.7, 29.7 ± 5.5 kg/m2 at 1, 3, and 5 years, respectively. The liver fat accumulation and visceral fat areas were significantly improved at 1 year after surgery. The decrease in the BMI, waist-hip ratio, body fat percentage, and basal metabolic rate remained decreased for at least 5 years after surgery. Blood test findings including AST, ALT, γ-GTP, uric acid, albumin, CRP, HDL cholesterol, LDL cholesterol, triglycerides, and homeostasis model assessment insulin resistance (HOMA-IR) were also still improved at least 5 years after surgery.

CONCLUSION

Bariatric surgery is useful for ensuring the long-term treatment of NAFLD/NASH in morbidly obese Japanese patients. Bariatric surgery is a therapeutic option for patients resistant to conventional treatment.

Non-invasive prediction of non-alcoholic steatohepatitis in Japanese patients with morbid obesity by artificial intelligence using rule extraction technology

AIM

To construct a non-invasive prediction algorithm for predicting non-alcoholic steatohepatitis (NASH), we investigated Japanese morbidly obese patients using artificial intelligence with rule extraction technology.

METHODS

Consecutive patients who required bariatric surgery underwent a liver biopsy during the operation. Standard clinical, anthropometric, biochemical measurements were used as parameters to predict NASH and were analyzed using rule extraction technology. One hundred and two patients, including 79 NASH and 23 non-NASH patients were analyzed in order to create the prediction model, another cohort with 77 patients including 65 NASH and 12 non-NASH patients were analyzed to validate the algorithm.

RESULTS

Alanine aminotransferase, C-reactive protein, homeostasis model assessment insulin resistance, albumin were extracted as predictors of NASH using a recursive-rule extraction algorithm. When we adopted the extracted rules for the validation cohort using a highly accurate rule extraction algorithm, the predictive accuracy was 79.2%. The positive predictive value, negative predictive value, sensitivity and specificity were 88.9%, 35.7%, 86.2% and 41.7%, respectively.

CONCLUSION

We successfully generated a useful model for predicting NASH in Japanese morbidly obese patients based on their biochemical profile using a rule extraction algorithm.

Advances and challenges in the management of advanced fibrosis in nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is rapidly becoming the most common type of chronic liver disease worldwide. From the spectrum of NAFLD, it is nonalcoholic steatohepatitis (NASH) that predominantly predisposes patients to higher risk for development of cirrhosis and hepatocellular carcinoma. There is growing evidence that the risk of progression to cirrhosis and hepatocellular carcinoma is not uniform among all patients with NASH. In fact, NASH patients with increasing numbers of metabolic diseases such as diabetes, hypertension, visceral obesity and dyslipidemia are at a higher risk of mortality. Additionally, patients with higher stage of liver fibrosis are also at increased risk of mortality. In this context, NASH patients with fibrosis are in the most urgent need of treatment. Also, the first line of treatment for NASH is lifestyle modification with diet and exercise. Nevertheless, the efficacy of lifestyle modification is quite limited. Additionally, vitamin E and pioglitazone may be considered for subset of patients with NASH. There are various medications targeting one or more steps in the pathogenesis of NASH being developed. These drug regimens either alone or in combination, may provide potential treatment option for patients with NASH.

Role of acoustic radiation force impulse imaging elastography in the assessment of steatohepatitis and fibrosis in rat models

Acoustic radiation force impulse (ARFI) elastography is a non-invasive method for performing liver assessment via liver shear wave velocity (SWV) measurements. The aim of this study was to evaluate the performance of the ARFI technique in the diagnosis of nonalcoholic steatohepatitis (NASH) and fibrosis and to investigate the effect of steatosis and inflammation on liver fibrosis SWV measurements in a rat model of nonalcoholic fatty liver disease (NAFLD). The ex vivo right liver lobes from 110 rats were processed and embedded in a fabricated gelatin phantom, and the other lobes were used for histologic assessment. The SWV induced by acoustic radiation force was derived to evaluate liver stiffness. The experimental results showed that the liver SWV value could be used to differentiate non-NASH rats from NASH-presenting rats and NASH from cirrhosis, and these comparisons showed areas under the receiver operating characteristic curves (AUROC) of 0.951 and 0.980, respectively. The diagnostic performances of ARFI elastography in predicting severe fibrosis (F ≥ 3) and cirrhosis (F ≥ 4) showed AUROC values of 0.997 and 0.993, respectively. In rats with mild fibrosis (F0-F1), severe steatosis had a significant effect on the mean SWV values. In rats with significant fibrosis (F2-F4), severe lobular inflammation had significant effects on the mean SWV values. Our findings indicate that ARFI elastography is a promising method for differentiating non-NASH rats from NASH rats and for staging hepatic fibrosis in NASH. The presence of severe steatosis and severe lobular inflammation are significant factors for evaluating fibrosis stages.

Usefulness of virtual touch quantification for staging liver fibrosis in patients with hepatitis C, and factors affecting liver stiffness measurement failure compared with liver biopsy

AIM

The assessment of liver fibrosis in patients with hepatitis C is important to predict carcinogenesis. In this study, we evaluated the usefulness of virtual touch quantification (VTQ) for staging liver fibrosis, and investigated factors causing discrepancies between the estimated fibrosis stage using VTQ and the pathological fibrosis stage.

METHODS

Patients with hepatitis C (n = 302) were assessed using VTQ and underwent pathological liver investigation within 1 week before and after VTQ. A receiver operator characteristic (ROC) curve was obtained for VTQ, fibrosis-4 (FIB-4) index, and aspartate aminotransferase-to-platelet ratio index (APRI), and each area under the ROC curve (AUROC) was compared to predict fibrosis stage. We used univariate and multivariate analyses to investigate the factors related to the discrepancy between the estimated fibrosis stage using VTQ and the pathological fibrosis stage.

RESULTS

At any stage, VTQ was the most accurate for staging liver fibrosis. The VTQ cut-off values were 1.33 m/s (AUROC = 0.822) for ≥F2, 1.51 m/s (AUROC = 0.836) for ≥F3, and 1.92 m/s (AUROC = 0.890) for F4. Skin liver capsule distance (SCD) was the most relevant factor for the discrepancy between the estimated fibrosis stage using VTQ and the pathological fibrosis stage. The SCD cut-off value was 17.5 mm.

CONCLUSIONS

Virtual touch quantification is a non-invasive, simple method that is more accurate for staging liver fibrosis than the FIB-4 index and APRI. However, when the SCD is longer than 17.5 mm, there may be measurement failures.

Assessment of transient elastography in Japanese patients with non-alcoholic fatty liver disease

AIM

Transient elastography (TE) is a non-invasive method for predicting liver fibrosis. However, there are limited data regarding the performance of TE in Japanese patients with non-alcoholic fatty liver disease (NAFLD). We aimed to evaluate the association between liver stiffness measurement (LSM) by TE and liver fibrosis stage, and define a cut-off value for predicting liver fibrosis.

METHODS

A total of 171 Japanese patients with biopsy-proven NAFLD underwent LSM using TE with FibroScan. The area under the receiver operating characteristic curve of LSM and other non-invasive markers of liver fibrosis were compared to determine the most accurate method of predicting liver fibrosis.

RESULTS

Liver stiffness measurement significantly correlated with fibrosis stage (P < 0.001). The areas under the receiver operating characteristic curve of LSM for fibrosis stage ≥1 and ≥3 was 0.85 and 0.91, respectively and were higher than those of the aspartate aminotransferase/alanine aminotransferase ratio, aspartate aminotransferase to platelet ratio index, fibrosis-4 index, and NAFLD fibrosis score. The best cut-off values of LSM fibrosis stage ≥1 and ≥3 were 7.2 kPa (sensitivity 78.5%, specificity 78.3%) and 10.0 kPa (sensitivity 89.5%, specificity 87.6%), respectively. The combination of LSM (≥10 kPa) and type IV collagen 7 s (≥6.0 ng/mL) had a specificity of 97.6% for advanced fibrosis. The LSM in patients with high alanine aminotransferase levels or high body mass index was associated with false positive results regarding advanced fibrosis.

CONCLUSIONS

In NAFLD patients, TE has excellent utility for the assessment of liver fibrosis, particularly for advanced stage cases. The cut-off value of LSM by TE for predicting liver fibrosis stage ≥3 is 10.0 kPa in Japanese NAFLD patients.

The inverse effect of meal intake on controlled attenuation parameter and liver stiffness as assessed by transient elastography

BACKGROUND

Controlled attenuation parameter (CAP) and liver stiffness (LS) measured by transient elastography (TE, Fibroscan®) have been used for steatosis and fibrosis assessment. We evaluated the effect of meal intake on CAP and LS values.

METHODS

Forty patients who had had a liver biopsy within the previous month were recruited. The biopsy was graded for fibrosis (F) and steatosis (S) stagings. TE was performed after overnight fasting (baseline values) and 15, 30, 45, 60, 90, and 120 min following the intake of a standard commercial formula meal, and every 30 min until LS and CAP values returned to baseline. The effect of meal intake on CAP and LS values was analyzed with a multilevel mixed model approach.

RESULTS

The mean age was 53.1 ± 11.2 years old. The mean (SD) BMI was 25.6 ± 4.5 kg/m². F0, F1, F2, F3 and F4 fibrosis stages were found in 17 (42.5%), 9 (22.5%), 4 (10.0%), 8 (20.0%) and 2 (5.0%), respectively. S0, S1, S2 and S3 steatosis stages were seen in 22 (55.0%), 11 (27.5%), 4 (10.0%) and 3 (7.5%), respectively. The mean (SD) CAP and median (IQR) LS values at baseline were 249.7 ± 58.1 dB/m and 11.9 (6-18.1) kPa. A significant decrease in CAP values was observed in all patients 15 to 120 min after meals, with the CAP peak value at 60 min and the mean post-meal delta reduction of 18.1 dB/min. CAP values declined after meals at early fibrosis stages and across all stages of steatosis. A significant increase in LS values after meal intake was observed within 15 to 120 min, with the LS peak value at 15 min and the mean post-meal delta increase of 2.4 kPa. Post-meal CAP and LS values returned to baseline within 150 min following meals.

CONCLUSION

Following a meal, patients' CAP values declined with the peak value at 60 min, contrasting with the rising of LS values with the peak value at 15 min. The post-meal CAP and LS values returned to baseline by 150 min. A fasting period of more than 150 min after a meal is recommended for patients undergoing TE.

Current complications and challenges in nonalcoholic steatohepatitis screening and diagnosis

Nonalcoholic steatohepatitis (NASH) can lead to complications such as liver failure, cirrhosis and hepatocellular carcinoma. The diagnostic gold standard for NASH is liver biopsy; however, other noninvasive methods have been developed. In this article, the authors evaluate current methods in NASH screening and diagnosis. Routine radiologic modalities were found to detect hepatic steatosis accurately, but were unable to establish the diagnosis of NASH or stage of fibrosis. Newly developed elastography based techniques seem promising to estimate liver fibrosis. Other noninvasive tests such as FibroTest, ELF, Hepascore, FIB-4, NFS, FLI and ION (biochemical panels) have AUROCs ranging between 0.80-0.98 for detecting advanced fibrosis but lack specificity for detecting mild fibrosis. Noninvasive tools, especially elastography, identify NASH associated advanced fibrosis potentially reducing liver biopsies. More research is needed to validate the clinical utility of these tests.

Controlled attenuation parameter is correlated with actual hepatic fat content in patients with non-alcoholic fatty liver disease with none-to-mild obesity and liver fibrosis

AIM

Non-invasive steatosis-quantifying methods are required for non-alcoholic fatty liver disease (NAFLD) patients in order to monitor disease severity and assess therapeutic efficacy. Controlled attenuation parameter (CAP) evaluated with vibration-controlled transient elastography can predict the presence of steatosis, but its application to absolute hepatic fat quantitation remains unclear. The aim of this st\udy was to examine whether CAP is correlated with real hepatic fat content in NAFLD patients.

METHODS

Eighty-two NAFLD patients who had undergone percutaneous liver biopsy were enrolled. CAP was measured using FibroScan(®) just before liver biopsy. The percentage of fat droplet area to hepatocyte area in biopsied specimen was determined morphometrically using computerized optical image analyzing system. The correlation between CAP and liver histology was examined.

RESULTS

CAP showed an excellent correlation with actual liver fat percentage in the NAFLD patients with body mass index (BMI) of less than 28 kg/m(2) (r = 0.579, P < 0.0001), especially less than 25 kg/m(2) (r = 0.708, P < 0.01), but the meaningful correlation disappeared in the patients with BMI of 28 kg/m(2) or more. In the patients with BMI of less than 28 kg/m(2) , CAP quantitativeness was affected by the presence of stage 2-4 fibrosis, but not the presence of hepatocyte ballooning and severity of lobular inflammation.

CONCLUSION

CAP may be a promising tool for quantifying hepatic fat content in NAFLD patients with none-to-mild obesity and liver fibrosis. Further improvement of CAP performance is needed for the NAFLD patients with BMI of more than 28 kg/m(2) or significant hepatic fibrosis.

ARFI: from basic principles to clinical applications in diffuse chronic disease-a review

Abstract

The many factors influencing the shear wave velocity (SWV) measured with Acoustic Radiation Force Impulse (ARFI) are examined in order to define the most correct examination technique. In particular, attention is given to the information achieved by experimental models, such as phantoms and animal studies. This review targets the clinical applications of ARFI in the evaluation of chronic diffuse disease, especially of liver and kidneys. The contribution of ARFI to the clinical workout of these patients and some possible perspectives are described.

Teaching Points

• Stiffness significantly varies among normal and abnormal biological tissues.

• In clinical applications physical, geometrical, anatomical and physiological factors influence the SWV.

• Elastographic techniques can quantify fibrosis, which is directly related to stiffness.

• ARFI can be useful in chronic diffuse disease of liver and kidney.

Noninvasive diagnosis of nonalcoholic fatty liver disease: Are we there yet?

Nonalcoholic fatty liver disease (NAFLD) has rapidly become the most common form of chronic liver disease in the United States affecting approximately 80-100 million Americans. NAFLD includes a spectrum of diseases ranging from nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH) to fibrosis and eventually cirrhosis. Patients with NASH and significant fibrosis on liver biopsy have an increased risk for liver-related morbidity and mortality compared to those with NAFL. Due to the high prevalence of NAFLD and its progressive nature, there has been an urgent need to develop reliable noninvasive tests that can accurately predict the presence of advanced disease without the need for liver biopsy. These tests can be divided into those that predict the presence of NASH and those that predict the presence of fibrosis. In this review, we provide a concise overview of different noninvasive methods for staging the severity of NAFLD.

Clinical applications, limitations and future role of transient elastography in the management of liver disease

Transient elastography (TE) is a reliable tool for the non-invasive assessment of liver fibrosis in routine clinical practice. TE is currently approved for use in Europe, Asia and the United States. The widespread adoption of this technology is certain to increase the use of TE worldwide. Although TE has been well validated in chronic viral hepatitis, its clinical role in other liver diseases remains less clear. The advent of new treatment for chronic hepatitis C and emerging prevalence of non-alcoholic steatohepatitis raises new questions on the role of TE in current clinical practice. This review aims to examine the clinical applications, limitations and future role of TE in current clinical practice in light of the changing epidemiology of liver diseases and new clinical management paradigms. In current clinical practice, TE is the most accurate non-invasive method for diagnosis of liver cirrhosis. TE is useful to rule out fibrosis and cirrhosis but does not have sufficient accuracy to discern between various stages of fibrosis. The clinical role of TE has evolved from cross-sectional point-in-time assessment of fibrosis and cirrhosis to the more relevant role of prediction of vital clinical end-points. This provides clinicians with the ability to modify treatment strategies based on the information provided by TE. TE has evolved over the past decade to become an essential tool to assist the clinician in the management of chronic liver disease.

Magnetic resonance elastography is superior to acoustic radiation force impulse for the Diagnosis of fibrosis in patients with biopsy-proven nonalcoholic fatty liver disease: A prospective study

Magnetic resonance elastography (MRE), an advanced magnetic resonance-based imaging technique, and acoustic radiation force impulse (ARFI), an ultrasound-based imaging technique, are accurate for diagnosing nonalcoholic fatty liver disease (NAFLD) fibrosis. However, no head-to-head comparisons between MRE and ARFI for diagnosing NAFLD fibrosis have been performed. We compared MRE versus ARFI head-to-head for diagnosing fibrosis in well-characterized patients with biopsy-proven NAFLD. This cross-sectional analysis of a prospective cohort involved 125 patients (54.4% female) who underwent MRE, ARFI, and contemporaneous liver biopsies scored using the Nonalcoholic Steatohepatitis Clinical Research Network histological scoring system. The performances of MRE versus ARFI for diagnosing fibrosis were evaluated using area under the receiver operating characteristic curves (AUROCs). The mean (± standard deviation) age and body mass index were 48.9 (±15.4) years and 31.8 (±7.0) kg/m(2) , respectively. For diagnosing any fibrosis (≥ stage 1), the MRE AUROC was 0.799 (95% confidence interval [CI] 0.723-0.875), significantly (P = 0.012) higher than the ARFI AUROC of 0.664 (95% CI 0.568-0.760). In stratified analysis by presence or absence of obesity, MRE was superior to ARFI for diagnosing any fibrosis in obese patients (P < 0.001) but not in nonobese patients (P = 0.722). The MRE AUROCs for diagnosing ≥stages 2, 3, and 4 fibrosis were 0.885 (95% CI 0.816-0.953), 0.934 (95% CI 0.863-1.000), and 0.882 (95% CI 0.729-1.000); and the ARFI AUROCs were 0.848 (95% CI 0.776-0.921), 0.896 (95% CI 0.824-0.968), and 0.862 (95% CI 0.721-1.000). MRE had higher AUROCs than ARFI for discriminating dichotomized fibrosis stages at all dichotomization cutoff points, but the AUROC differences decreased as the cutoff points (fibrosis stages) increased.

CONCLUSION

MRE is more accurate than ARFI for diagnosing any fibrosis in NAFLD patients, especially those who are obese.

Ultrasound elastography: liver

Ultrasound elastography, also termed sonoelastography, is being used increasingly in clinical practice to aid the diagnosis and management of diffuse liver disease. Elastography has been shown to be capable of differentiating advanced and early-stage liver fibrosis, and consequently a major application in clinical liver care includes progression to cirrhosis risk stratification through (1) assessment of liver fibrosis stage in HCV and HBV patients, (2) distinguishing non-alcoholic steatohepatitis from simple steatosis in non-alcoholic fatty liver disease patients, and (3) prognostic evaluation of liver disease is autoimmune liver disease. In addition, elastographic characterization of focal liver lesions and evaluation of clinically significant portal hypertension have the potential to be clinically useful and are areas of active clinical research.

Comparative study and systematic review of laparoscopic liver resection for hepatocellular carcinoma

AIM: To compare the surgical outcomes between laparoscopic liver resection (LLR) and open liver resection (OLR) as a curative treatment in patients with hepatocellular carcinoma (HCC).

METHODS: A PubMed database search was performed systematically to identify comparative studies of LLR vs OLR for HCC from 2000 to 2014. An extensive text word search was conducted, using combinations of search headings such as “laparoscopy”, “hepatectomy”, and “hepatocellular carcinoma”. A comparative study was also performed in our institution where we analysed surgical outcomes of 152 patients who underwent liver resection between January 2005 to December 2012, of which 42 underwent laparoscopic or hand-assisted laparoscopic resection and 110 underwent open resection.

RESULTS: Analysis of our own series and a review of 17 high-quality studies showed that LLR was superior to OLR in terms of short-term outcomes, as patients in the laparoscopic arm were found to have less intraoperative blood loss, less blood transfusions, and a shorter length of hospital stay. In our own series, both LLR and OLR groups were found to have similar overall survival (OS) rates, but disease-free survival (DFS) rates were higher in the laparoscopic arm.

CONCLUSION: LLR is associated with better short-term outcomes compared to OLR as a curative treatment for HCC. Long-term oncologic outcomes with regards to OS and DFS rates were found to be comparable in both groups. LLR is hence a safe and viable option for curative resection of HCC.

Vitamin E reduces liver stiffness in nonalcoholic fatty liver disease

AIM: To evaluate the efficacy of vitamin E treatment on liver stiffness in nonalcoholic fatty liver disease (NAFLD).

METHODS: Thirty-eight NAFLD patients were administered vitamin E for > 1 year. The doses of vitamin E were 150, 300, or 600 mg; three times per day after each meal. Responses were assessed by liver enzyme levels [aspartate aminotransferase (AST), alanine aminotranferease (ALT), and γ-glutamyl transpeptidase (γ-GTP)], noninvasive scoring systems of hepatic fibrosis-4 [FIB-4 index and aspartate aminotransferase-to-platelet index (APRI)], and liver stiffness [velocity of shear wave (Vs)] measured by acoustic radiation force impulse elastography. Vs measurements were performed at baseline and 12 mo after baseline. The patients were genotyped for the patatin-like phospholipase domain containing 3 (PNPLA3) polymorphisms and then divided into either the CC/CG or GG group to examine each group’s responses to vitamin E treatment.

RESULTS: We found marked differences in the platelet count, serum albumin levels, alkaline phosphatase levels, FIB-4 index, APRI, and Vs at baseline depending on the PNPLA3 polymorphism. AST, ALT, and γ-GTP levels (all P < 0.001); FIB-4 index (P = 0.035); APRI (P < 0.001); and Vs (P < 0.001) significantly decreased from baseline to 12 mo in the analysis of all patients. In the subset analyses of PNPLA3 genotypes, AST levels (P = 0.011), ALT levels (P < 0.001), γ-GTP levels (P = 0.005), APRI (P = 0.036), and Vs (P = 0.029) in genotype GG patients significantly improved, and AST and ALT levels (both P < 0.001), γ-GTP levels (P = 0.003), FIB-4 index (P = 0.017), and APRI (P < 0.001) in genotype CC/CG patients.

CONCLUSION: One year of vitamin E treatment improved noninvasive fibrosis scores and liver stiffness in NAFLD patients. The responses were similar between different PNPLA3 genotypes.

Evaluation of Transient Elastography, Acoustic Radiation Force Impulse Imaging (ARFI), and Enhanced Liver Function (ELF) Score for Detection of Fibrosis in Morbidly Obese Patients

BACKGROUND

Liver fibrosis induced by non-alcoholic fatty liver disease causes peri-interventional complications in morbidly obese patients. We determined the performance of transient elastography (TE), acoustic radiation force impulse (ARFI) imaging, and enhanced liver fibrosis (ELF) score for fibrosis detection in bariatric patients.

PATIENTS AND METHODS

41 patients (median BMI 47 kg/m2) underwent 14-day low-energy diets to improve conditions prior to bariatric surgery (day 0). TE (M and XL probe), ARFI, and ELF score were performed on days -15 and -1 and compared with intraoperative liver biopsies (NAS staging).

RESULTS

Valid TE and ARFI results at day -15 and -1 were obtained in 49%/88% and 51%/90% of cases, respectively. High skin-to-liver-capsule distances correlated with invalid TE measurements. Fibrosis of liver biopsies was staged as F1 and F3 in n = 40 and n = 1 individuals. However, variations (median/range at d-15/-1) of TE (4.6/2.6-75 and 6.7/2.9-21.3 kPa) and ARFI (2.1/0.7-3.7 and 2.0/0.7-3.8 m/s) were high and associated with overestimation of fibrosis. The ELF score correctly classified 87.5% of patients.

CONCLUSION

In bariatric patients, performance of TE and ARFI was poor and did not improve after weight loss. The ELF score correctly classified the majority of cases and should be further evaluated.

Metabolic imaging in obesity: underlying mechanisms and consequences in the whole body

Obesity is a phenotype resulting from a series of causative factors with a variable risk of complications. Etiologic diversity requires personalized prevention and treatment. Imaging procedures offer the potential to investigate the interplay between organs and pathways underlying energy intake and consumption in an integrated manner, and may open the perspective to classify and treat obesity according to causative mechanisms. This review illustrates the contribution provided by imaging studies to the understanding of human obesity, starting with the regulation of food intake and intestinal metabolism, followed by the role of adipose tissue in storing, releasing, and utilizing substrates, including the interconversion of white and brown fat, and concluding with the examination of imaging risk indicators related to complications, including type 2 diabetes, liver pathologies, cardiac and kidney diseases, and sleep disorders. The imaging modalities include (1) positron emission tomography to quantify organ-specific perfusion and substrate metabolism; (2) computed tomography to assess tissue density as an indicator of fat content and browning/ whitening; (3) ultrasounds to examine liver steatosis, stiffness, and inflammation; and (4) magnetic resonance techniques to assess blood oxygenation levels in the brain, liver stiffness, and metabolite contents (triglycerides, fatty acids, glucose, phosphocreatine, ATP, and acetylcarnitine) in a variety of organs.

Higher Matrix Stiffness Upregulates Osteopontin Expression in Hepatocellular Carcinoma Cells Mediated by Integrin β1/GSK3β/β-Catenin Signaling Pathway

Increased stromal stiffness is associated with hepatocellular carcinoma (HCC) development and progression. However, the molecular mechanism by which matrix stiffness stimuli modulate HCC progress is largely unknown. In this study, we explored whether matrix stiffness-mediated effects on osteopontin (OPN) expression occur in HCC cells. We used a previously reported in vitro culture system with tunable matrix stiffness and found that OPN expression was remarkably upregulated in HCC cells with increasing matrix stiffness. Furthermore, the phosphorylation level of GSK3β and the expression of nuclear β-catenin were also elevated, indicating that GSK3β/β-catenin pathway might be involved in OPN regulation. Knock-down analysis of integrin β1 showed that OPN expression and p-GSK3β level were downregulated in HCC cells grown on high stiffness substrate compared with controls. Simultaneously, inhibition of GSK-3β led to accumulation of β-catenin in the cytoplasm and its enhanced nuclear translocation, further triggered the rescue of OPN expression, suggesting that the integrin β1/GSK-3β/β-catenin pathway is specifically activated for matrix stiffness-mediated OPN upregulation in HCC cells. Tissue microarray analysis confirmed that OPN expression was positively correlated with the expression of LOX and COL1. Taken together, high matrix stiffness upregulated OPN expression in HCC cells via the integrin β1/GSK-3β/β-catenin signaling pathway. It highlights a new insight into a pathway involving physical mechanical signal and biochemical signal molecules which contributes to OPN expression in HCC cells.

Acoustic Radiation Force Impulse Elastography for the Non-Invasive Evaluation of Hepatic Fibrosis in Non-Alcoholic Fatty Liver Disease Patients: A Systematic Review & Meta-Analysis

Background

In order to better monitor non-alcoholic fatty liver disease (NAFLD) patients at higher risk for HCC, there is a need for non-invasive diagnostic approaches to screen for the presence of advanced fibrosis in these patients. The aim of this systematic review and meta-analysis will be to evaluate the diagnostic efficacy of ARFI elastography in detecting hepatic fibrosis in NAFLD patients.

Methods

Relevant studies were identified from systematic searches of several major electronic databases (PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials). The primary outcomes were the summary sensitivity, summary specificity, the diagnostic odds ratio, and the summary receiver operating characteristic curve (SROC) of ARFI elastography in detecting significant fibrosis (defined as 4>F≥2) in NAFLD patients. Study quality was assessed using the Quality Assessment of Studies of Diagnostic Accuracy included in Systematic Review (QUADAS-2).

Results

The summary sensitivity and specificity of ARFI in detecting significant fibrosis were 80.2% (95% confidence interval (CI): 0.758–0.842; p = 0.0000) and 85.2% (95% CI: 0.808–0.890), p = 0.1617), respectively. The pooled diagnostic odds ratio of ARFI in detecting significant fibrosis was 30.13 (95% CI: 12.08–75; chi-squared = 14.59, p = 0.0237). The area under the SROC curve (AUC) was 0.898 (standard error (SE): 0.031) with a Q* index of 0.830 (SE: 0.033).

Conclusions

ARFI elastography appears to be modestly accurate in detecting significant fibrosis in NAFLD patients. Future studies in this field should provide head-to-head comparisons of ARFI elastography versus other elastographic imaging modalities in NAFLD patients.

Composite prognostic models across the non-alcoholic fatty liver disease spectrum: Clinical application in developing countries

Heterogeneity in clinical presentation, histological severity, prognosis and therapeutic outcomes characteristic of non-alcoholic fatty liver disease (NAFLD) necessitates the development of scientifically sound classification schemes to assist clinicians in stratifying patients into meaningful prognostic subgroups. The need for replacement of invasive liver biopsies as the standard method whereby NAFLD is diagnosed, graded and staged with biomarkers of histological severity injury led to the development of composite prognostic models as potentially viable surrogate alternatives. In the present article, we review existing scoring systems used to (1) confirm the presence of undiagnosed hepatosteatosis; (2) distinguish between simple steatosis and NASH; and (3) predict advanced hepatic fibrosis, with particular emphasis on the role of NAFLD as an independent cardio-metabolic risk factor. In addition, the incorporation of functional genomic markers and application of emerging imaging technologies are discussed as a means to improve the diagnostic accuracy and predictive performance of promising composite models found to be most appropriate for widespread clinical adoption.

Normal liver stiffness: A study in living donors with normal liver histology

AIM: To define the normal range of liver stiffness (LS) values using transient elastography in living-related liver transplantation candidate donors with normal liver histology.

METHODS: LS was measured using Fibroscan in 50 (16 women, 34 men) healthy potential donors (mean age 28.4 ± 5.9 years) who were being evaluated for liver donation for their relatives at the National Liver Institute, Menoufeya University, Egypt. All potential donors had normal liver tests and were negative for hepatitis B or C virus infection. Abdominal ultrasounds showed normal findings. None of the subjects had diabetes, hypertension, renal impairment, heart disease, or body mass index > 30 kg/m². All subjects had normal liver histology upon liver biopsy. They all donated the right lobe of their liver with successful outcomes.

RESULTS: The mean LS was 4.3 ± 1.2 kPa (range: 1.8-7.1 kPa). The 5^th and 95^th percentiles of normal LS were 2.6 kPa and 6.8 kPa, respectively, with a median of 4 kPa; the interquartile range was 0.6 ± 0.4. LS measurements were not significantly different between men and women (4.4 ± 1.1 kPa vs 3.9 ± 1.3 kPa) and did not correlate with age. However, stiffness values were significantly lower in subjects with a body mass index < 26 kg/m² compared to those with an index ≥ 26 kg/m² (4.0 ± 1.1 kPa vs 4.6 ± 1.2 kPa; P <0.05). There were no differences in hospital stay or postoperative bilirubin, albumin,alanine and aspartate transaminases, or creatinine levels (at discharge) between donors with livers stiffness ≤ 4 kPa and those with stiffness > 4 kPa.

CONCLUSION: Healthy donors with normal liver histology have a median LS of 4 kPa. Stiffness values are elevated relative to increase in body mass index.

Non-invasive Testing for NASH and NASH with Advanced Fibrosis: Are We There Yet?

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent etiology of chronic liver disease in America. NAFLD can be broadly classified in two subtypes: nonalcoholic fatty liver (NAFL), which is generally considered a benign condition with negligible risk of progression to cirrhosis, and nonalcoholic steatohepatitis (NASH), which is generally considered to be progressive with substantial risk of progression to cirrhosis. Additionally, recent studies suggest the odds of liver mortality increases amongst NASH patients with advanced fibrosis (bridging fibrosis ± cirrhosis). Liver biopsy examination is the current gold standard to accurately discriminate between NAFL vs. NASH as well as diagnose advanced fibrosis. However, due to its invasive nature, risk of bleeding (and even rarely death), prohibitive cost, and sampling error, liver biopsies are imperfect for diagnosis and monitoring of NAFLD. As a result, noninvasive biomarkers that can accurately detect NASH and advanced fibrosis without biopsy are needed. This article will discuss the most novel noninvasive biomarkers in diagnosing NASH and advanced fibrosis.

Circulating miRNA-122 levels are associated with hepatic necroinflammation and portal hypertension in HIV/HCV coinfection

BACKGROUND

Introduction of combined antiretroviral therapy (cART) has improved survival of HIV infected individuals, while the relative contribution of liver-related mortality increased. Especially in HIV/HCV-coinfected patients hepatic fibrosis and portal hypertension represent the main causes of liver-related morbidity and mortality. Circulating miRNA-122 levels are elevated in HIV patients and have been shown to correlate with severity of liver injury. However, the association of miRNA-122 levels and hepatic fibrosis and portal hypertension remains to be explored in HIV/HCV coinfection.

METHODS

From a total of 74 (31% female) patients with HIV/HCV coinfection were included. Serum levels of miRNA-122 were analyzed by quantitative polymerase chain reaction (PCR) and normalized to SV-40 spike-in RNA. Hepatic venous pressure gradient (HVPG) was measured in 52 (70%) patients and the fibrosis stage was determined in 63 (85%) patients using transient elastography.

RESULTS

The levels of circulating miRNA-122 were increased in HIV/HCV coinfected patients and significantly correlated with the alanine aminotransferase (ALT) (rs = 0.438; p<0.001) and aspartate transaminase AST values (rs = 0.336; p = 0.003), but not with fibrosis stage (p = n.s.). Interestingly, miRNA-122 levels showed an inverse correlation with hepatic venous pressure gradient (HVPG) (rs = -0.302; p = 0.03).

CONCLUSION

Elevated miRNA-122 levels are associated with liver injury, and with low HVPG. Though, miRNA-122 levels are not suitable to predict the degree of fibrosis, they might function as indicators for portal hypertension in HIV/HCV coinfected patients.