Noninvasive diagnosis of liver fibrosis by ultrasonic transient elastography (Fibroscan)

Fibulin-4 as a potential extracellular vesicle marker of fibrosis in patients with cirrhosis

Chronic liver injury leads to decreased liver function and increased fibrosis. Fibrosis is not only associated with the development of portal hypertension and carcinogenesis, but with the occurrence of events and a poor prognosis, highlighting the importance of non-invasive fibrosis assessment in patients. In the present study, we searched for markers related to liver fibrosis via proteomic analysis of small extracellular vesicles (sEVs). In the discovery cohort, proteomic analysis was carried out in the sEVs extracted from the sera of 5 patients with decompensated cirrhosis, 5 patients with compensated cirrhosis, and 5 controls without liver disease. Interestingly, in this cohort, fibulin-4 was significantly associated with cirrhosis while in the validation cohort [formed by 191 patients: 7 patients without disease, 16 patients without liver disease (other diseases), 38 patients with chronic liver disease (CLD), 75 patients with cirrhosis of Child-Pugh class A (36 without hepatocellular carcinoma [HCC], 29 with HCC), and 65 patients with cirrhosis of Child-Pugh class B-C (39 without HCC, 26 with HCC)], fibulin-4/CD9 levels increased with cirrhosis progression. Furthermore, the fibulin-4/CD9 ratio was significantly higher in patients with varices. Immunostaining also revealed strong fibulin-4 expression in cholangiocytes within the fibrous areas and mesothelial cells in liver tissue blood vessels. Taken together, our results suggest that fibulin-4, essential for lysyl oxidase activation, might be a new liver fibrosis marker found in the sEVs of patients with cirrhosis.

Shear wave elastography: How well does it perform in chronic hepatitis D virus infection?

Hepatitis delta virus (HDV) infection is associated with accelerated progression of liver disease to cirrhosis. Shear wave elastography (SWE) is a non-invasive evaluation method of liver fibrosis. Its performance in accurately characterizing HDV fibrosis compared to other noninvasive markers remains unknown. We assessed the performance of SWE in patients with chronic HDV, Hepatitis B (HBV) and Hepatitis C (HCV) infection. Cirrhosis was determined by histology or clinical data. Area under receiver operator characteristics (AUROC) was used to assess diagnostic performance in identifying cirrhosis by SWE in comparison with Fibroscan® (VCTE) and serologic tests of fibrosis. 158 patients with chronic hepatitis (HDV:44%, HBV: 46% and HCV: 29%) were evaluated. Cirrhosis was diagnosed in 28 (17.7%) patients. Mean noninvasive fibrosis measurements for the HBV/HCV and HDV groups, respectively, were as follows: APRI: 0.73 ± 1.08 and 1.3 ± 1.38; FIB-4: 1.90 ± 2.24 and 2.33 ± 2.24; VCTE: 8.9 ± 6.7 kPa vs 10.4 ± 5.3 kPa; SWE: 1.5 ± 0.2 m/s and 1.6 ± 0.2 m/s. The performance of SWE in detecting HDV-induced cirrhosis (AUROC 0.84, 95% CI 0.71-0.97) was slightly lower than in HBV/HCV induced disease (AUROC 0.88, 95% CI 0.81-0.96). For HDV patients, the performance of SWE was comparable to VCTE and slightly better than APRI and FIB-4 especially in APRI and FIB-4 indeterminate zones. The overall less accurate performance of noninvasive markers in HDV in comparison with HBV and HCV may be a result of significant hepatic inflammation in HDV.

Elastography: a surrogate marker of renal allograft fibrosis - quantification by shear-wave technique

Purpose

Renal fibrosis is the most common cause of allograft failure in kidney transplantations. Evaluation of renal abnormalities has progressed considerably over the past years. Currently, the diagnosis of intrarenal fibrosis and quantification of its development with non-invasive assessment tools is possible. This may help in early detection of renal allograft dysfunction. This study sought to assess the efficacy of 2D real-time shear-wave elastography (SWE) in the quantitative measurement of renal allograft dysfunction.

Methods

A total of 172 patients were included in our study. SWE was performed in all these patients just before renal allograft biopsy. The cortical elasticity was assessed and described in terms of Young’s modulus (kPa). Banff histopathological grading obtained from transplant kidney tissue biopsy was taken as the reference standard. The potential correlation between SWE scores and Banff classification was performed.

Results

There was a significant correlation between the Banff grade and mean SWE score, with a correlation coefficient of 0.665 (p < 0.001). The individual correlation coefficients of interstitial fibrosis and tubular atrophy with mean SWE score stood at 0.667 and 0.649 respectively (p < 0.001). The correlation of resistive indices was insignificant when compared to mean polar SWE score in respective poles and the Banff grading of fibrosis.

Conclusions

Renal stiffness quantified by 2D SWE showed significant correlation with histopathological renal fibrosis. Thus, the study suggests that shear-wave elastography could be used as a surrogate marker for early detection of renal fibrosis.

Usefulness of serum Mac-2 binding protein glycosylation isomer in patients undergoing hepatectomy: A case controlled study

Background

To evaluate the clinical significance of Mac-2 binding protein glycosylation isomer (M2BPGi), we investigated the relationship between M2BPGi and clinicopathological and surgical parameters and posthepatectomy complications.

Materials and methods

We examined M2BPGi in 115 patients with hepatic malignancies undergoing hepatectomy. Significance as an independent prognostic marker was determined with multivariate logistic regression analysis.

Results

The mean serum M2BPGi level was 1.14 ± 1.03 C.O.I. (range 0.2–5.79). M2BPGi in the chronic viral hepatitis group (1.42 ± 1.25) was significantly higher than that in the other disease groups (p < 0.05). The M2BPGi level correlated negatively with platelet count, LHL15 and GSA-Rmax (r = −0.36, −0.69 and −0.56, respectively; p < 0.01) but correlated positively with serum hyaluronate level (fibrotic marker), ICGR15 and HH15 (r = 0.52, 0.63 and 0.57, respectively; p < 0.01). In 53 patients examined for histological hepatic fibrosis, the M2BPGi level was highest for hepatic fibrosis stage 4, indicating cirrhosis (2.15 ± 1.56), and was significantly higher than that for stages 0–2 (p < 0.05). M2BPGi level did not correlate significantly with any surgical parameters. The preoperative level correlated significantly only with increased alanine aminotransferase level (r = −0.21, p < 0.05) and was significantly higher in patients with (1.35 ± 0.78) than without (1.11 ± 1.07) hepatectomy-related complications (p < 0.05). Area under the ROC curve analysis for prediction of hepatic fibrosis score 4 showed a cut-off value of 0.78 for M2BPGi to have high sensitivity (90%) and specificity (58%). For postoperative hepatectomy-related complications, only the M2BPGi level (at a cut-off value 0.90) tended to show significance (p = 0.06).

Conclusions

The non-invasively measured serum level of M2BPGi reflected impaired liver function or cirrhosis and hepatectomy-related complications after surgery, making it potentially useful as a complementary parameter accompanying other liver function parameters.

•

The M2BPGi level was higher in patients with posthepatectomy complications.

•

The M2BPGi level correlated negatively with the platelet count, LHL 15 and GSA-Rmax by liver scintigraphy.

•

The M2BPGi level was highest in the patients with hepatic fibrosis.

Noninvasive Fibrosis Assessment in Chronic Viral Hepatitis C associated with End Stage Renal Disease

INTRODUCTION

HCV is considered the most encountered viral infection that affect patients after hemodialysis sessions. Even though liver biopsy is considered the golden standard for hepatic diagnosis, additional methods have been used for assessing liver fibrosis. Transient elastography (TE) has evolved as a reference method in some European countries and allows the physician to carry out a fibrosis evaluation in a noninvasive, low-cost and rapid method. Our objective was to assess the efficacy of TE in staging patients with HCV liver disease associated with ESRD, thus choosing the correct moment to perform the procedure.

MATERIALS AND METHODS

We included 34 patients known with ESRD within the regional Nephrology Clinic of Olt County Hospital and also having positive hepatitis C viral liver marker. TE was performed before and hemodialysis and data was analyzed.

RESULTS

The patients where we have encountered significant changes were especially within the F0 and F1 stage with a decrease of fibrosis after hemodialysis. Thus, 7 patients which had no fibrosis (F0) went from 4,14±0,98kPa to 3,54±0,84 (p<0,05) and 12 patients from the F1 stage went from 6,22±0,39kPa to 5,47±0,58kPa. The other stages had no significant changes with F2 changing after hemodialysis from 8.03±0,62kPa to 7, 76±0,6kPa.

CONCLUSIONS

TE represents a valuable tool for stiffness assessment and should be taken into considerations as a major option for ESRD patients with liver disease. However, more patients should be enrolled to strengthen this theory and thus providing more reliable results.

Elbasvir/grazoprevir and sofosbuvir for hepatitis C virus genotype 3 infection with compensated cirrhosis: A randomized trial

Many direct-acting antiviral regimens have reduced activity in people with hepatitis C virus (HCV) genotype (GT) 3 infection and cirrhosis. The C-ISLE study assessed the efficacy and safety of elbasvir/grazoprevir (EBR/GZR) plus sofosbuvir (SOF) with and without ribavirin (RBV) in compensated cirrhotic participants with GT3 infection. This was a phase 2, randomized, open-label study. Treatment-naive participants received EBR/GZR + SOF + RBV for 8 weeks or EBR/GZR + SOF for 12 weeks, and peginterferon/RBV treatment-experienced participants received EBR/GZR + SOF ± RBV for 12 weeks or EBR/GZR + SOF for 16 weeks. The primary endpoint was HCV RNA <15 IU/mL 12 weeks after the end of treatment (sustained virologic response at 12 weeks [SVR12]). Among treatment-naive participants, SVR12 was 91% (21/23) in those treated with RBV for 8 weeks and 96% (23/24) in those treated for 12 weeks. Among treatment-experienced participants, SVR12 was 94% (17/18) and 100% (17/17) in the 12-week arm, with and without RBV, respectively, and 94% (17/18) in the 16-week arm. Five participants failed to achieve SVR: 2 relapsed (both in the 8-week arm), 1 discontinued due to vomiting/cellulitis (16-week arm), and 2 discontinued (consent withdrawn/lost to follow-up). SVR12 was not affected by the presence of resistance-associated substitutions (RASs). There was no consistent change in insulin resistance, and 5 participants reported serious adverse events (pneumonia, chest pain, opiate overdose, cellulitis, decreased creatinine). High efficacy was demonstrated in participants with HCV GT3 infection and cirrhosis. Treatment beyond 12 weeks was not required, and efficacy was maintained regardless of baseline RASs.

CONCLUSION

Data from this study support the use of EBR/GZR plus SOF for 12 weeks without RBV for treatment-naive and peginterferon/RBV-experienced people with GT3 infection and cirrhosis (ClinicalTrials.gov NCT02601573). (Hepatology 2018;67:2113-2126).

Utility of Shear Wave Elastography for Assessing Allograft Fibrosis in Renal Transplant Recipients: A Pilot Study

OBJECTIVES

To evaluate the utility of ultrasound-based shear wave elastography (SWE) as a noninvasive method to accurately detect and potentially stage the severity of renal allograft fibrosis and assess its user reproducibility.

METHODS

In this Institutional Review Board-approved, Health Insurance Portability and Accountability Act-compliant prospective study, 70 renal transplant recipients underwent an SWE evaluation of their allograft followed directly by biopsy. Two radiologists performed separate SWE measurement acquisitions and the mean, median, and standard deviation of 10 SWE measurements, obtained separately within the cortex and the medulla, were automatically computed. Each patient's SWE results were subsequently compared to their histologic fibrosis scores. The Fisher exact test and univariate logistic regression models were fit to test for associations between the presence of fibrosis (yes/no) as well as categorical SWE results based on the fibrosis severity, ranging from F0 (no fibrosis) to F3 (severe fibrosis), correlating with histologic scores according to the 2007 Banff classification system. Interobserver and intraobserver correlations were also examined.

RESULTS

Our median medulla SWE values reached statistical significance (P = .04) in association with fibrosis. Furthermore, for every unit increase in the median medulla SWE measurement, the odds of fibrosis increased by approximately 20%. No statistical significance was found for mean cortical, median cortical, or mean medullary SWE values (P = .32, .37, and .06, respectively) in association with fibrosis.

CONCLUSIONS

The use of SWE for assessing renal allograft fibrosis is challenging but promising. Further investigation with a larger sample size remains to validate our initial results and establish clinical relevance.

Non-invasive assessment of kidney allograft fibrosis with shear wave elastography: A radiological-pathological correlation analysis

OBJECTIVES

To evaluate the use of shear wave elastography in assessment of kidney allograft tubulointerstitial fibrosis.

METHODS

Shear wave elastography assessment was carried out by two independent operators in kidney transplant recipients who underwent allograft biopsy for clinical indications (i.e. rising creatinine >15% or proteinuria >1 g/day). Allograft biopsies were interpreted by the same pathologist according to the 2013 Banff Classification.

RESULTS

A total of 40 elastography scans were carried out (median creatinine 172.5 μmol/L [interquartile range 133.8-281.8 μmol/L]). Median tissue stiffness at the cortex (22.6 kPa [interquartile range 18.8-25.7 kPa] vs 22.3 kPa [interquartile range 19.0-26.5 kPa], P = 0.70) and medulla (15.0 kPa [interquartile range 13.7-18.0 kPa] vs 15.6 kPa [interquartile range 14.4-18.2 kPa]) showed no significant differences between the two observers. Interobserver agreement was satisfactory (intraclass correlation coefficient of the cortex 0.84, 95% CI 0.70-0.92 and intraclass correlation coefficient of the medulla 0.88, 95% CI 0.78-0.94). The areas under the receiver operating characteristic curves for detection of tubulointerstitial fibrosis were estimated to be 0.75 (95% CI 0.61-0.89), 0.85 (95% CI 0.75-0.95) and 0.65 (95% CI 0.53-0.78) for cortical, medullary tissue stiffness and serum creatinine, respectively.

CONCLUSIONS

Shear wave elastography can be used as a non-invasive tool to evaluate kidney allograft fibrosis with reasonable interobserver agreement and superior test performance to serum creatinine in detecting early tubulointerstitial fibrosis.

Assessment of Liver Fibrosis by Transient Elastography Should Be Done After Hemodialysis in End Stage Renal Disease Patients with Liver Disease

BACKGROUND AND AIMS

The patients with end stage renal disease (ESRD) are at greater risk of acquiring chronic hepatitis B or C and subsequently development of liver disease. The aim of the study was to assess liver fibrosis by transient elastography (TE) and look for factors associated with change in liver stiffness measurement (LSM) with one session of hemodialysis (HD).

METHODS

Consecutive ESRD patients on maintenance hemodialysis (MHD) with suspected liver disease were enrolled. They underwent LSM by TE before and after one session of HD. Bioelectric impedance analysis was done to evaluate the volume status at the time of TE.

RESULTS

Sixty-eight patients with mean age of 40 ± 14 years were included. There was a significant reduction in LSM after HD (18.5 [95% CI 14.8-23.1] vs. 11.2 [95% CI 8.8-13.7] kPa, p < 0.001), with a mean LSM reduction of 7.2 [95% CI 5.25-9.19] kPa. On stratification in two groups by net ultrafiltration during HD (> or < 2.5 liters [L]), change in LSM was substantially higher in patients when total fluid removed was > 2.5 L (8.6 [95% CI 5.7-11.5] vs. 5.1 [95% CI 2.9-7.5], p = 0.05). In 18 patients who underwent liver biopsy, LSM after HD performed better at detecting significant fibrosis, with area under receiver operating characteristics curve 0.71 [95% CI 0.46-0.97], versus 0.64 [95% CI 0.38-0.90], respectively. An LSM value of 12.2 kPa after HD was 71% sensitive and 74% specific for detection of significant fibrosis (≥ F2), while values less than 9 kPa ruled out significant fibrosis with a sensitivity and specificity of 37 and 100%, respectively.

CONCLUSION

LSM by TE decreases significantly after HD in patients with ESRD on long-term MHD. Hence, TE should be done after HD for accurate assessment of liver fibrosis.

Challenges and Considerations When Using Shear Wave Elastography to Evaluate the Transplanted Kidney, With Pictorial Review

The gold standard in evaluating renal allograft dysfunction has traditionally been renal biopsy. However, not only does biopsy come with inherent risks, the time frame from biopsy to detecting renal dysfunction is often inefficient. It is therefore advantageous to have a noninvasive, low-cost, time-saving method, such as shear wave elastography (SWE), to detect fibrosis early, to maximize immunosuppressive care. It is important to consider factors that affect tissue stiffness in the kidney, as well as the challenges incurred when using SWE in this anisotropic organ, in order to select the most appropriate patients for this exam.

Usefulness of evaluating hepatic elasticity using artificial acoustic radiation force ultrasonography before hepatectomy

AIM

To evaluate hepatic fibrosis and tumor diagnosis preoperatively, we investigated the elasticity calculated by the new parameter of ultrasonography, acoustic radiation force impulse (ARFI).

METHODS

We examined ARFI of the non-tumorous right and left lateral liver and in the tumor by push pulse of probe in 95 patients with hepatic malignancies undergoing hepatectomy. Measurement of ARFI as hepatic stiffness was indicated as the Vs (m/s).

RESULTS

Measuring the Vs in the non-tumor region was achieved in the right liver in 99% and at the left lateral liver in 94%. The Vs in the right liver was significantly lower than in the left lateral liver, and the Vs of the liver tumor was significantly higher than in the non-tumorous liver. The Vs in the right and left lateral liver was correlated with the platelet count, aspartate aminotransferase, fibrotic indices and indocyanine green test. The Vs in the right liver was significantly correlated with the fibrotic marker or index. The Vs of liver cirrhosis and histological stage 4 in the right and left liver was significantly the highest compared to the others. The Vs in the right liver showed a high area under the receiver-operator curve value predicting histological fibrosis. The Vs in the right was significantly correlated with blood loss and postoperative complications, particularly uncontrolled ascites.

CONCLUSION

Non-invasive ARFI imaging elastography is useful in evaluating impaired liver function or in the differential diagnosis of liver malignancies, highly hepatic fibrosis and in predicting posthepatectomy morbidity.

Significance of serum and hepatic microRNA-122 levels in patients with non-alcoholic fatty liver disease

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is believed to be a type of metabolic syndrome. MicroRNA-122 (miR-122) is the most abundant microRNA in the liver and is an important factor for the metabolism of glucose and lipids. In the present study, we examined the correlation between the hepatic and serum miR-122 expression levels and the clinicopathological factors of patients with NAFLD.

METHODS

We extracted the total RNA, along with preserved miRNAs, from liver biopsy samples of 67 patients with NAFLD. In 52 of these 67 patients, the total RNA was extracted from serum. The miR-122 that was obtained by quantitative reverse transcription-polymerase chain reaction was quantified using TaqMan MicroRNA assays.

RESULTS

A significant correlation was detected between serum and hepatic miR-122 expression (correlation coefficient, 0.461; P=0.005). Patients with mild steatosis (<33%) showed significantly lower levels of hepatic miR-122 compared with patients with severe steatosis (>33%) (hepatic miR-122: mild/severe=2.158±1.786/4.836±7.506, P=0.0473; serum miR-122: mild/severe=0.002±0.005/0.007±0.001, P=0.0491). Moreover, hepatic and serum miR-122 levels were significantly higher in patients with mild fibrosis than in those with severe fibrosis (hepatic miR-122: mild/severe=5.201±7.275/2.394±1.547, P=0.0087; serum miR-122: mild/severe=0.008±0.011/0.002±0.004, P=0.0191).

CONCLUSIONS

We found that the hepatic and serum miR-122 levels were associated with hepatic steatosis and fibrosis. The serum miR-122 level can be a useful predictive marker of liver fibrosis in patients with NAFLD.

CT volumetry of the liver: where does it stand in clinical practice?

Imaging-based volumetry has been increasingly utilised in current clinical practice to obtain accurate measurements of the liver volume. This is particularly useful prior to major hepatic resection and living donor liver transplantation where the size of the remnant liver and liver graft, respectively, affects procedural success and postoperative mortality and morbidity. The use of imaging-based volumetry, with emphasis on computed tomography, will be reviewed. We will explore the various technical factors that contribute to accurate volumetric measurements, and demonstrate how the accuracies of these techniques are influenced by their methodologies. The strengths and limitations of using anatomical imaging to estimate liver volume will be discussed, in relation to laboratory and functional imaging methods of assessment.

Congestive hepatopathy after Fontan operation and related factors assessed by transient elastography

OBJECTIVE

Congestive hepatopathy after a Fontan operation can have a major effect on long-term morbidity. We evaluated congestive hepatopathy in patients with Fontan circulation using transient elastography to determine which risk factors for hepatopathy are related to liver stiffness (LS).

METHODS

We evaluated 46 patients with Fontan circulation and 26 with right side heart failure (RHF) and hepatic congestion using laboratory tests, the aspartate aminotransferase-to-platelet ratio index, ultrasonography, and transient elastography.

RESULTS

The LS value was significantly greater in the Fontan group (21.1±8.0 kPa) than in the RHF group (10.0±9.0 kPa). The total bilirubin and albumin serum levels, white blood cell count, and aspartate aminotransferase to platelet ratio index correlated significantly with LS in the Fontan group. Of the risk factors, age at evaluation (r=0.42, P=.004), age at Fontan completion (r=0.51, P<.001), inferior vena cava diameter (r=0.35, P=.02), and spleen size (r=0.53, P=.002) correlated significantly with LS. Nineteen patients in the Fontan group (41.3%) had abnormal ultrasound findings, and the frequency of abnormal findings increased with increasing LS (P=.002). In the subgroup with the greatest LS value (≥30 kPa), 88.9% had abnormal ultrasound findings and 44.4% liver cirrhosis. Multivariate analysis revealed that age at Fontan procedure completion and total bilirubin were independent risk factors for hepatopathy.

CONCLUSIONS

The present study revealed that congestive hepatopathy developed in a significant fraction of patients with long-term Fontan circulation and that transient elastography could be an easy and useful method to assess congestive hepatopathy in these patients.

Cost and time savings from a rapid access model of care using transient elastography to screen and triage patients with chronic Hepatitis C infection

BACKGROUND

Treatment uptake amongst patients with chronic Hepatitis C virus (HCV) in Australia is relatively low. New approaches to assessment have the potential to reduce public waiting lists, improve access to treatment, and to reduce healthcare costs.

AIM

To describe the costs to the public hospital system and waiting time associated with a novel integrated rapid access to assessment and treatment (RAAT) model of care that utilizes Transient Elastography (TE) as a specialist outpatient-based approach for a streamlined assessment of patients with chronic HCV, compared to conventional outpatient management with liver biopsy (LB).

METHODS

Time from first medical review to treatment plan and costs associated with detection of fibrosis were recorded for patients receiving RAAT during a 3-month period, and for a similar historical cohort managed conventionally with LB. Costs related to medical and multidisciplinary team reviews and the TE/LB test itself were included.

RESULTS

Patients receiving RAAT had lower costs (n = 27, median AU$2716) and shorter time to treatment (median = 194 days) than for conventional management (n = 13, median $5005, 420 days; p < 0.01). Differences related to the lower TE test costs and the lower cost of consults between first medical review and establishment of a treatment plan.

CONCLUSIONS

Based on real world audit data, this evaluation suggests TE, used as part of a new RAAT model of care, is cost saving to the health system in the short-term and reduces waiting times. The analysis reported here was intended to assess the costs related to detection of fibrosis, and is limited by the small sample size and potential selection bias. Future research should undertake a full economic evaluation at a whole of service level, to consider a more comprehensive and longer-term assessment of the costs and benefits associated with HCV management.

The use of DWI to assess spleen and liver quantitative ADC changes in the detection of liver fibrosis stages in chronic viral hepatitis

This study aimed to evaluate the changes in spleen and liver diffusion-weighted magnetic resonance imaging (DWI) in chronic viral hepatitis patients. The study comprised 47 patients and 30 healthy volunteers. DWIs were obtained. Apparent Diffusion Coefficient (ADC) measurements were made by transferring the images to the workstation. The measurements of value b 1000 were made from a total of five points of the liver and three points of the spleen. Liver biopsy was performed on the 47 patients. The fibrosis stages of the patients were defined according to the METAVIR scoring system. Student's t-test was used in the comparison of mean ages, liver and spleen ADC values between the patient and the control group. Kruskal-Wallis followed by Mann-Whitney U Test with Bonferroni adjustment was performed in the comparison of mean ADC values of the patients at different stages and the control group. A statistically significant difference was determined between the patient and control group in respect of liver and spleen mean ADC values (P<0.05). F3 group showed a significant difference compared to control and F1 and F4 group showed a significant difference compared to control, F1, F2 and F3 group in terms of the mean liver ADC value (P<0.01). F3 and F4 group showed a significant difference compared to control and F1 group in terms of the mean spleen ADC value (P<0.01). As a result we believe that the measurement of liver and spleen ADC values may be an indicator in the determination of the level of fibrosis.

The effect of hemodialysis on liver stiffness measurement: a single-center series

BACKGROUND/AIMS

The noninvasive measurement of liver stiffness using transient elastography (TE) is increasingly being used alongside liver biopsy. However, several conditions may lead to higher liver stiffness values without reflecting more fibrosis. Such conditions (e.g. hepatitis, cholestasis, heart failure, mechanical ventilation) limit the interpretation of liver stiffness measurements. The influence of hemodialysis on the measurement of liver stiffness has not been investigated to date. Here, we analyzed liver stiffness assessed by fibroscan in 17 patients directly before and after a hemodialysis session.

PATIENTS AND METHODS

Measurement of hepatic stiffness by TE was carried out using the Fibroscan device with the 'M probe' directly before and directly after one session of hemodialysis. Each measurement consisted of at least 10 individual and valid measurements, with a success rate of at least 60%, and an interquartile range of less than 25%. All measurements were carried out by one investigator not involved in patient management.

RESULTS

Before dialysis, the median TE was 5.1 kPa (2.8-17 kPa). Ten patients had values below the threshold of 7.1 kPa and seven patients had TE>7.1 kPa. The median net fluid withdrawal by hemodialysis was 2.5 l (0.4-3.1 l) and did not differ between patients. After dialysis, the TE median was 7.4 kPa (3.5-12.5 kPa) and had changed in all patients except one. Liver stiffness increased significantly when the initial TE was lower than 7.1 kPa (P=0.05), but not when the initial TE was higher than 7.1 kPa. Furthermore, the magnitude of the change in TE after hemodialysis correlated inversely with the liver stiffness before hemodialysis (P=0.03) and with spleen length measured by ultrasound (P=0.03).

CONCLUSION

This study is the first to report on the influence of hemodialysis on liver stiffness measurement. In contrast to previous reports, liver stiffness might increase after fluid withdrawal if patients do not show significant fibrosis. We conclude that before dialysis, TE possibly better differentiates between patients with or without significant fibrosis.

[What is expected from the novel triple combination antiviral treatment of patients infected with hepatitis C virus genotype 1?]

INTRODUCTION

Since May 2011, protease inhibitor/ribavirin/peginterferon combination has become the standard treatment for both treatment-naive and treatment-experienced patients infected with hepatitis C virus genotype 1. In Hungary, due to limited resources, the therapy of treatment-experienced patients might only be financed in the near future.

AIM

The aim of this retrospective study was to find out characteristics of the patient group waiting for new triple combination in a single hepatology centre in Hungary, and to estimate the possible rate of their sustained virologic response.

METHOD

Between January 2004 and September 2012, 269 patients with chronic hepatitis C virus infection were treated with peginterferon/ribavirin therapy. 142 patients failed to achieve sustained virologic response, but out of them, 93 individuals are the possible candidates for the triple antiviral treatment. In the latter group, the previous virologic response to dual therapy was determined. To register fibrosis scores, findings of liver biopsy and/or fibroelastography were also collected. Interleukin28B genotypes of 49 patients were determined.

RESULTS

Among the 93 treatment-experienced patients, 25 relapsed, 26 responded partially , 6 broke through, and 36 null-responders were found. 29% of patients had mild or moderate fibrosis and 71% of those already had severe fibrosis. Of the 49 patients with known interleukin28B genotype only 8 patients had the CC genotype.

CONCLUSIONS

About half of the patients (mostly relapsers, and some partial responders as well) have a good chance of achieving sustained virologic response, which may be influenced by the fibrosis score.

Hepatic and serum levels of miR-122 after chronic HCV-induced fibrosis

BACKGROUND & AIMS

The progression of liver fibrosis in patients with chronic hepatitis C (CHC) is important to decide on the treatment of the virus. As liver biopsy and liver stiffness measurement for staging of fibrosis present limitations, circulating levels of miR-122 have been suggested as a novel biomarker to predict the extent of liver injury. We evaluated the potential of miR-122 as an indicator of fibrosis progression in CHC infection and performed, for the first time, a comprehensive analysis of hepatic and circulating miR-122 levels in patients with CHC.

METHODS

Patients with well-documented CHC infection were selected from the database of HepNet, the German-Competence-Network on Viral Hepatitis. All patients underwent blood sampling and liver biopsy with grading of inflammation and staging of fibrosis. RNA was extracted from 84 liver biopsies and 164 serum samples of CHC patients. miR-122 levels in liver and serum samples were quantified by real-time PCR normalized to RNU6 or spiked-in RNA, respectively.

RESULTS

Hepatic levels of miR-122 decreased significantly with the severity of fibrosis (p = 0.001). In addition, circulating miR-122 levels correlated negatively with increasing stages of fibrosis, although the inverse correlation was moderate due to a two-phase miR-122 pattern during fibrosis progression. Thus, circulating miR-122 levels decreased in patients with severe fibrosis (F3, F4), while at early stages with distinct fibrotic structures (F2) and high inflammatory activity, miR-122 serum levels were elevated.

CONCLUSIONS

We conclude that during progression of fibrosis less miR-122 is released into the blood stream due to the loss of liver cells and the decrease of hepatic miR-122 levels. Although the release of circulating miR-122 possibly mirrors acute liver injury, in chronic liver disease and fibrosis, the loss of liver cells and the decreased hepatocellular miR-122 expression render miR-122 an inappropriate marker, when exclusively used for interpretation of fibrosis progression.

Quantitative elastography of renal transplants using supersonic shear imaging: a pilot study

PURPOSE

To evaluate the reliability of quantitative ultrasonic measurement of renal allograft elasticity using supersonic shear imaging (SSI) and its relationship with parenchymal pathological changes.

MATERIALS AND METHODS

Forty-three kidney transplant recipients (22 women, 21 men) (mean age, 51 years; age range, 18-70 years) underwent SSI elastography, followed by biopsy. The quantitative measurements of cortical elasticity were performed by two radiologists and expressed in terms of Young's modulus (kPa). Intra- and inter-observer reproducibility was assessed (Kruskal-Wallis test and Bland-Altman analysis), as well as the correlation between elasticity values and clinical, biological and pathological data (semi-quantitative Banff scoring). Interstitial fibrosis was evaluated semi-quantitatively by the Banff score and measured by quantitative image analysis.

RESULTS

Intra- and inter-observer variation coefficients of cortical elasticity were 20 % and 12 %, respectively. Renal cortical stiffness did not correlate with any clinical parameters, any single semi-quantitative Banff score or the level of interstitial fibrosis; however, a significant correlation was observed between cortical stiffness and the total Banff scores of chronic lesions and of all elementary lesions (R = 0.34, P = 0.05 and R = 0.41, P = 0.03,respectively).

CONCLUSION

Quantitative measurement of renal cortical stiffness using SSI is a promising non-invasive tool to evaluate global histological deterioration.

KEY POINTS

• Supersonic shear imaging elastography can measure cortical stiffness in renal transplants • The level of cortical stiffness is correlated with the global degree of tissue lesions • The global histological deterioration of transplanted kidneys can be quantified using elastography.

Discordance between CD4+ T-lymphocyte counts and percentages in HIV-infected persons with liver fibrosis

BACKGROUND

Cirrhosis of the liver can induce splenic sequestration of peripheral blood cells, recently suggested to reduce the number but not percentage of circulating CD4(+) T cells in persons uninfected with human immunodeficiency virus (HIV). We investigated whether earlier stages of liver fibrosis prior to cirrhosis were associated with discordance between CD4 count (CD4N) and CD4 percentage (CD4%) in HIV-infected patients.

METHODS

In cross-sectional analysis of 287 HIV-infected participants of the AIDS Linked to the Intravenous Experience cohort, we evaluated CD4N, CD4%, and transient elastography staging of liver fibrosis. High CD4(+) lymphocyte discordance was defined as higher CD4% relative to CD4N based on accepted clinical cutoffs; multivariable logistic regression was used to determine covariates associated with discordance.

RESULTS

Of 287 participants, 99 (34.4%) had high CD4(+) discordance, which increased to 76% of 114 participants with marked lymphopenia (total lymphocyte count [TLC] ≤1200 cells/μL). In multivariable analysis, the odds of having high CD4(+) discordance was increased in persons with significant liver fibrosis compared to those without fibrosis (odds ratio, 1.69; 95% confidence interval [CI], .95-2.96); the odds ratio of discordance increased to 2.66 (95% CI, 1.11-6.40) among the subset of participants with TLC ≤1200 cells/μL. The odds for discordance associated with cirrhosis were of similar magnitude as those observed with significant fibrosis.

CONCLUSIONS

In HIV-infected persons, liver fibrosis is associated with discordant peripheral CD4(+) lymphocyte results, especially in the setting of marked lymphopenia. Clinicians should also consider CD4% when interpreting absolute CD4(+) counts of HIV-infected persons with known or suspected liver disease, particularly if TLC is <1200 cells/μL.

A biomarker panel for non-alcoholic steatohepatitis (NASH) and NASH-related fibrosis

BACKGROUND

Patients with biopsy-proven NASH and especially those with fibrosis are at risk for progressive liver disease, emphasizing the clinical importance of developing non-invasive biomarkers for NASH and NASH-related fibrosis.

AIM

This study examines the performance of a new biomarker panel for NASH and NASH-related fibrosis with a combination of clinical and laboratory variables.

METHODS

Enrolled patients had biopsy-proven NAFLD. Clinical data, laboratory data, and serum samples were collected at the time of biopsy. Fasting serum was assayed for adiponectin, resistin, glucose, M30, M65, Tissue inhibitor of metalloproteinases-1 (Timp-1), ProCollagen 3 N-terminal peptide (PIIINP), and hyaluronic acid (HA). Regression models predictive of NASH, NASH-related fibrosis, and NASH-related advanced fibrosis were designed and cross-validated.

RESULTS

Of the 79 enrolled NAFLD patients, 40 had biopsy-proven NASH and 39 had non-NASH NAFLD. Clinical and laboratory data were from this cohort were used to develop a NAFLD Diagnostic Panel that includes three models (models for NASH, NASH-related fibrosis, and NASH-related advanced fibrosis). The model for predicting NASH includes diabetes, gender, BMI, triglycerides, M30 (apoptosis), and M65-M30 (necrosis) [AUC: 0.81, 95% CI, 0.70-0.89, 300 p value <9E 301 (-06)]. The NASH-related fibrosis prediction model includes the same predictors [AUC: 0.80, 95% CI 0.68-0.88, 307 p value <0.00014]. Finally, the NASH-related advanced fibrosis model includes type 2 diabetes, serum triglycerides, Timp-1, and AST [AUC: 0.81, 95% CI, 0.70-0.89; p value, 0.000062].

CONCLUSIONS

This NAFLD Diagnostic Panel based on a clinical and laboratory data has good performance characteristics and is easy to use. This biomarker panel could become useful in the management of patients with NAFLD.

Comparison of non-invasive assessment to diagnose liver fibrosis in chronic hepatitis B and C patients

OBJECTIVE

Chronic viral hepatitis B and C cause liver fibrosis, leading to cirrhosis. Fibrosis assessment is essential to establish prognosis and treatment indication. We compared seven non-invasive tests, separately and in combination, in chronic hepatitis patients to detect early stages of fibrosis according to the Metavir score in liver biopsy.

MATERIAL AND METHODS

Galactose and methacetin breath tests (GBT and MBT), biomarkers (hyaluronic acid (HA), aspartate aminotransferase platelet ratio index (APRI), FibroTest, and Fib-4) and transient elastography (TE) were evaluated in 89 patients. Additionally, 31 healthy controls were included for evaluation of breath tests and biomarkers.

RESULTS

Serum markers (HA, APRI, FibroTest, and Fib-4) and elastography significantly distinguished non-cirrhotic (F0123) from cirrhotic (F4) patients (p < 0.001, p = 0.015, p < 0.001, p = 0.005, p = 0.006, respectively). GBT, HA, APRI, FibroTest, Fib-4, and TE detected F01 from F234 (p = 0.04, p = 0.011, p = 0.009, p < 0.001, p < 0.001, and p < 0.001, respectively). A combination of different tests (TE, HA, and FibroTest) improved the performance statistically, area under the curve (AUC) = 0.87 for F234, 0.92 for F34, and 0.90 for F4.

CONCLUSION

HA, APRI, FibroTest, Fib-4, and TE reliably distinguish non-cirrhotic and cirrhotic patients. Except for MBT, all tests discriminate between mild and moderate fibrosis. As single tests: FibroTest, Fib-4, and TE were the most accurate for detecting early fibrosis; combining different non-invasive tests increased the accuracy for detection of liver fibrosis to such an extent and thus might be acceptable to replace liver biopsy.

Recent advances in imaging hepatic fibrosis and steatosis

Liver disease is an increasing cause of morbidity and mortality worldwide. Currently, the gold standard for diagnosis and assessment of parenchymal disease is histopathological assessment of a percutaneous or transjugular liver biopsy. The risks and limitations of this technique are well recognized and as a result, significant effort has gone into the development of novel noninvasive methods of diagnosis and longitudinal assessment. Imaging techniques have improved significantly over the past decade and new technologies are beginning to enter clinical practice. Ultrasound, computed tomography and MRI are the main modalities currently used, but novel MRI-based techniques will have an increasing role. While there has been extensive research into the imaging of focal liver disease, the evidence base for imaging in diffuse disease has also undergone recent rapid development, particularly in the assessment of fibrosis and steatosis. Both of these abnormalities of the parenchyma can lead to cirrhosis and/or hepatocellular carcinoma and represent an important opportunity for detection of early liver disease. We discuss the recent advances in liver imaging techniques and their role in the diagnosis and monitoring of diffuse liver disease, with a focus on their current and potential clinical relevance and whether they may replace or augment liver biopsy. We also discuss techniques currently under development and their potential clinical applications in the future.

Risk factors for advanced liver fibrosis in HIV-infected individuals: role of antiretroviral drugs and insulin resistance

Liver damage may result from multiple factors in HIV-infected patients. The availability of reliable noninvasive tools to measure liver fibrosis has permitted the screening of large patient populations. Cross-sectional study of all consecutive HIV outpatients who underwent examination by transient elastometry (FibroScan) at one HIV reference clinic during 2007. Advanced liver fibrosis (ALF) was defined as hepatic stiffness >9.5 kilopascals, which corresponds to Metavir stages F3-F4 in the liver biopsy. A total of 681 consecutive HIV-infected patients (64% injecting drug users; mean age 43; 78% male; 98% on antiretroviral therapy) had at least one valid FibroScan evaluation. ALF was diagnosed in 215 (32%) of them. In the univariate analysis, ALF was significantly associated with older age, low CD4 counts, chronic hepatitis C, past alcohol abuse, elevated ALT, high triglycerides, low cholesterol, high homeostasis model assessment (HOMA) index and exposure to didanosine and/or stavudine. In a multivariate model (OR, 95% CI), chronic hepatitis C (2.83, 1.57-5.08), past alcohol abuse (2.26, 1.37-3.74), exposure to didanosine and/or stavudine (1.85, 1.14-3.01), high HOMA index (1.25, 1.04-1.51), older age (1.09, 1.05-1.14) and elevated ALT (1.04, 1.03-1.06) remained as independently associated with ALF. Therefore, in addition to chronic hepatitis C and alcohol abuse, insulin resistance and/or exposure to dideoxy-nucleosides may contribute to ALF in HIV-infected patients.

Effects of interventions on intra- and interobserver agreement on interpretation of nonalcoholic fatty liver disease histology

Accurate and reproducible interpretation of nonalcoholic fatty liver disease (NAFLD) histology has significant clinical and research-related implications. We evaluated the impact of 2 interventions ([1] review of illustrative histologic images of NAFLD with the study pathologists; [2] use of a scoring sheet with written diagnostic criteria for different NAFLD phenotypes) on intra- and interobserver agreement on interpretation of NAFLD histology. Before and after the interventions, 2 pathologists twice read 65 liver biopsies done for evaluation of suspected NAFLD. The intra- and interobserver agreement was highest on assessment of steatosis and fibrosis. The interventions significantly improved the intraobserver agreement only on assessment of hepatocellular ballooning. The interobserver agreement was only fair on assessment of lobular inflammation, ballooning, and diagnostic classification and did not improve after the interventions. Methods to improve interobserver agreement on assessment of lobular inflammation and ballooning are needed and would likely increase pathologists' agreement on NAFLD diagnostic classification.

Interobserver concordance in the assessment of liver fibrosis in HIV/HCV-coinfected patients using transient elastometry

OBJECTIVES

Although the reproducibility of transient elastometry (TE) in hepatitis C virus (HCV)-monoinfected patients seems to be high, this may not be the case in HIV/HCV-coinfected patients because of different degrees of steatosis and/or inflammation. This study was aimed to determine the interobserver concordance of TE measurements in HIV/HCV-coinfected patients.

METHODS

A total of 188 patients were evaluated in a cross-sectional, prospective study in two hospitals. The interobserver variability of TE results and the rate of unequal classification of significant fibrosis (cutoff value = 7.2 kPa) and cirrhosis (cutoff value = 14.6 kPa) for two observers were evaluated.

RESULTS

The values of liver stiffness (LS) for two observers highly correlated [intraclass correlation index = 0.976; 95% confidence interval (CI): 0.968-0.982]. The kappa indexes for the concordance of patient classification were 0.60 for significant fibrosis and 0.89 for cirrhosis. Using two cutoff points to diagnose or rule out significant fibrosis (LS >or=9 kPa or <6 kPa) yielded a kappa index of 0.96, but 46% of patients were not classified. Covariables that influenced the interobserver agreement were a high interquartile range in the determination (adjusted odd ratio: 0.189; 95% CI: 0.087-0.411; P = 0.001) and elevated levels of triglycerides (adjusted odd ratio: 1.004; 95% CI: 1.000-1.008; P = 0.031).

CONCLUSION

TE measurement is an observer-independent method to evaluate LS in HIV/HCV coinfected patients. The concordance of the classification of mild-to-severe fibrosis is good and for the diagnosis of cirrhosis is excellent. Lower interquartile ranges and triglyceride levels lead to a higher interobserver agreement.

Independent predictors of fibrosis in patients with nonalcoholic fatty liver disease

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is a common cause of chronic liver disease. We investigated factors associated with advanced fibrosis in NAFLD.

METHODS

The study included 432 patients with histologically proven NAFLD (26.8% with nonalcoholic steatohepatitis [NASH] and 17.4% with moderate-to severe fibrosis). NASH was defined as steatosis, lobular inflammation, and ballooning degeneration with or without Mallory-Denk bodies and/or fibrosis. Fibrosis was classified into 2 groups: those with no or minimal fibrosis and those with moderate-to-severe fibrosis. Groups were compared using Mann-Whitney and chi-square method analyses. A model was constructed using a stepwise bidirectional method; its predictive power was measured using a 10-fold cross-validation technique.

RESULTS

Patients with NASH were more likely to be male (P < .0001); have lower hip-to-waist ratios (P = .03); were less likely to be African American (P = .06); have higher levels of alanine aminotransferase (ALT; P < .0001), aspartate aminotransferase (AST; P < .0001), and serum triglycerides (P = .0154), but lower levels of high-density lipoprotein cholesterol (P < .0001). Patients with moderate-to-severe fibrosis were older (P = .0245); more likely to be male (P = .0189), Caucasian (P = .0382), have diabetes mellitus (P = .0238), and hypertension (P = .0375); and have a lower hip-to-waist ratio (P = .0077) but higher serum AST (P < .0001) and ALT (P < .0001) levels. The multivariate analysis model to predict moderate-to-severe fibrosis included male sex, Caucasian ethnicity, diabetes mellitus, and increased AST and ALT levels (model P value < .0001).

CONCLUSIONS

In patients with NAFLD, diabetes mellitus and aminotransferase levels are independent predictors of moderate-to-severe fibrosis. They can be used to identify NAFLD patients at risk for advanced fibrosis.

1-D elasticity assessment in soft solids from shear wave correlation: the time-reversal approach

One-channel time-reversal (TR) experiments allow focalization of waves in reverberant cavities. According to the Rayleigh criterion, the focal spot width is directly related to the wavelength and therefore depends on the mechanical properties of the medium. Thus, the general idea of this work is to extract quantitative estimations of these mechanical properties using a time-reversal approach based on cross-correlations of the wave field. An external source creates mechanical waves in the audible frequency range. One component of the vectorial field is measured along a line as function of time with signal processing developed in the field of 1-D elastography. The shear wavelength information is deduced from these mechanical waves using spatiotemporal correlations and interpreted in the frame of the time-reversal symmetry. The impact of wave attenuation in soft solids is reduced using a spatial average of the correlation field. The result is shown to be suitable for global elasticity estimation. The advantage is that the technique is almost independent of the source kind, shape, and time excitation function. This robustness as regard to shear wave source allows translation of this technique to applications in the medical field, including deep or moving organs.

Performance of 11 biomarkers for liver fibrosis assessment in HIV/HBV co-infected patients

BACKGROUND/AIMS

The aim of this study was to compare the performance of 11 biochemical scores to estimate liver fibrosis in HIV/HBV co-infection.

METHODS

Performance was evaluated using the Receiver Operating Characteristics (ROC) curve method. The Kappa index was used to study overall agreement with liver biopsy results. Interpretative algorithms were established by optimizing sensitivity and specificity and the percentage of correctly classified patients.

RESULTS

One hundred and eight patients (F0-F1, n = 47; F2, n = 28; F3, n = 17; F4, n = 16) were considered for the evaluation of serum biomarker performance. The AUROCs of the Fibrotest, Hepascore, Fibrometer, and Zeng's scores ranged from 0.74 to 0.77 for significant fibrosis (> or = F2), from 0.79 to 0.84 for advanced fibrosis (> or = F3) and from 0.87 to 0.92 for cirrhosis (F4). Thresholds defined for each stage of fibrosis were close to those previously published for the Fibrotest and Hepascore. Strict concordance with biopsies correctly classified 50% of the patients.

CONCLUSIONS

Fibrotest, Fibrometer, Hepascore, and Zeng's score were the most accurate non-invasive biochemical scores for liver fibrosis assessment in HIV/HBV co-infection. Global performance of biomarkers was not significantly improved by a decision tree combining the results of two biochemical scores.

Transient elastography for the prediction of oxaliplatin-associated liver injury in colon cancer patients: a preliminary analysis

OBJECTIVE

The prognosis of advanced colon cancer has improved significantly over the last decade since new chemotherapy regimens including oxaliplatin have been developed. However, oxaliplatin-induced liver injury and characterized hepatic hemostatic status can occur after chemotherapy. The assessment of this type of liver injury is often difficult.

METHODS

Elastography (Fibroscan) was used to evaluate liver injury in five cases before and after 5-FU, leucovorin, and oxaliplatin combination (FOLFOX) treatment.

RESULTS

A clear change was observed in the stiffness of liver after chemotherapy within 48 h, and the hepatic stiffness was normalized in most cases after 2 weeks. Among the five patients, one patient showed aberrant elevation after a FOLFOX treatment, and the patient showed liver injury pathologically.

CONCLUSION

Elastography is a good tool for evaluating hepatic injury after FOLFOX treatment.

Hereditary haemochromatosis

Haemochromatosis should currently refer to hereditary iron overload disorders presenting with a definite and common phenotype characterised by normal erythropoiesis, increased transferrin saturation and ferritin and primarily parenchymal iron deposition related to innate low (but normally regulated) production of the hepatic peptide hormone hepcidin. Since the discovery of the haemochromatosis gene (HFE) in 1996, several novel gene defects have been detected, explaining the mechanism and diversity of iron overload diseases. Overall, at least four main types of hereditary haemochromatosis (HH) have been identified. This review describes the systematic diagnostic and therapeutic strategy and pitfalls for patients suspected for HH and their relatives.

Liver cirrhosis: intravoxel incoherent motion MR imaging--pilot study

PURPOSE

To retrospectively evaluate a respiratory-triggered diffusion-weighted (DW) magnetic resonance (MR) imaging sequence combined with parallel acquisition to allow the calculation of pure molecular-based (D) and perfusion-related (D*, f) diffusion parameters, on the basis of the intravoxel incoherent motion (IVIM) theory, to determine if these parameters differ between patients with cirrhosis and patients without liver fibrosis.

MATERIALS AND METHODS

The institutional review board approved this retrospective study; informed consent was waived. IVIM DW imaging was tested on three alkane phantoms, on which the signal-intensity decay curves according to b factors were logarithmically plotted. Ten b factors (0, 10, 20, 30, 50, 80, 100, 200, 400, 800 sec/mm(2)) were used in patients. Patients with documented liver cirrhosis (cirrhotic liver group, n = 12) and patients without chronic liver disease (healthy liver group, n = 25) were included. The mean liver D, D*, and f values were measured and compared with the apparent diffusion coefficient (ADC) computed by using four b values (0, 200, 400, 800 sec/mm(2)). Liver ADC and D, f, and D* parameters were compared between the cirrhotic liver group and healthy liver group. Means were compared by using the Student t test.

RESULTS

Signal-intensity decay curves were monoexponential on phantoms and biexponential in patients. In vivo, mean ADC values were significantly higher than D in the healthy liver group (ADC = 1.39 x 10(-3) mm(2)/sec +/- 0.2 [standard deviation] vs D = 1.10 x 10(-3) mm(2)/sec +/- 0.7) and in the cirrhotic liver group (ADC = 1.23 x 10(-3) mm(2)/sec +/- 0.4 vs D = 1.19 x 10(-3) mm(2)/sec +/- 0.5) (P = .03). ADC and D* were significantly reduced in the cirrhotic liver group compared with those in the healthy liver group (respective P values of .03 and .008).

CONCLUSION

Restricted diffusion observed in patients with cirrhosis may be related to D* variations, which reflect decreased perfusion, as well as alterations in pure molecular water diffusion in cirrhotic livers.

Noninvasive monitoring of hepatitis C fibrosis progression

Noninvasive approaches in the diagnosis and monitoring of fibrosis are still evolving. Transient elastography is an inexpensive, rapid, and relatively accurate form of noninvasive monitoring, especially in severe fibrosis It is a nascent technology, however, and there is no clear indication that elastography is better than biopsy for less severe fibrosis. With improved resolution and longer term data, it may become a vital supplement. The combined use of transient elastography and biochemical markers seems to be the most promising noninvasive technique.

Review article: epidemiology, pathogenesis and potential treatments of paediatric non-alcoholic fatty liver disease

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of paediatric liver disease. Similar to NAFLD in adults, NAFLD in children is associated with obesity and insulin resistance and requires liver histology for diagnosis and staging. However, significant histological differences exist between adult and paediatric NAFLD to warrant caution in extrapolation of adult data.

AIM

To review the available data on the epidemiology, pathogenesis, diagnosis and treatment of paediatric NAFLD.

METHODS

Relevant articles were identified by Medline searches using the keywords: nonalcoholic fatty liver disease, steatohepatitis, obesity and children.

RESULTS

The rise in childhood obesity has been accompanied by an increase in paediatric NAFLD. Age, gender and race/ethnicity are significant determinants of risk, and sex hormones, insulin sensitivity and adipocytokines are implicated in the pathogenesis of paediatric NAFLD. There is no consensus for treatment of NAFLD; however, data suggest that diet, exercise and some pharmacological therapies may be of benefit.

CONCLUSIONS

To evaluate and effectively treat paediatric NAFLD, the pathophysiology and natural history of the disease should be clarified and non-invasive methods for screening, diagnosis, and longitudinal assessment developed. Randomized, controlled, double-blind trials of pharmacological therapies in children with biopsy-proven disease are necessary.

Nonalcoholic fatty liver disease

OBJECTIVE

The inflammatory subtype of nonalcoholic fatty liver disease, nonalcoholic steatohepatitis, is becoming one of the most important causes of chronic liver disease. In this article, we discuss the epidemiology, pathogenesis, and clinical and radiologic diagnosis of the subtypes of nonalcoholic fatty liver disease.

CONCLUSION

We discuss the current and evolving imaging tests in the evaluation of hepatic fatty content, inflammation, and fibrosis.

Performance of transient elastography for the staging of liver fibrosis: a meta-analysis

BACKGROUND & AIMS

Transient elastography has been studied in a multitude of liver diseases for the staging of liver fibrosis with variable results. A meta-analysis was performed to assess the overall performance of transient elastography for the diagnosis of liver fibrosis and to analyze factors influencing the diagnostic accuracy.

METHODS

Literature databases and international conference abstracts were searched. Inclusion criteria were as follows: evaluation of transient elastography, liver biopsy as reference, and assessment of the area under the receiver operating characteristic curve (AUROC). The meta-analysis was performed using the random-effects model for the AUROC, summary receiver operating curve techniques, as well as meta-regression approaches.

RESULTS

Fifty studies were included in the analysis. The mean AUROC for the diagnosis of significant fibrosis, severe fibrosis, and cirrhosis were 0.84 (95% confidence interval [CI], 0.82-0.86), 0.89 (95% CI, 0.88-0.91), and 0.94 (95% CI, 0.93-0.95), respectively. For the diagnosis of significant fibrosis a significant reduction of heterogeneity of the AUROC was found when differentiating between the underlying liver diseases (P < .001). Other factors influencing the AUROC were the scoring system used and the country in which the study was performed. Age, body mass index, and biopsy quality did not have a significant effect on the AUROC.

CONCLUSIONS

Transient elastography can be performed with excellent diagnostic accuracy and independent of the underlying liver disease for the diagnosis of cirrhosis. However, for the diagnosis of significant fibrosis, a high variation of the AUROC was found that is dependent on the underlying liver disease.

Quantitative assessment of hepatic fibrosis in an animal model with magnetic resonance elastography

Chronic liver disease is a world-wide problem that causes progressive hepatic fibrosis as a hallmark of progressive injury. At present, the gold standard for diagnosing hepatic fibrosis is liver biopsy, which is an invasive method with many limitations, including questionable accuracy and risks of complications. MR elastography (MRE), a phase-contrast MRI technique for quantitatively assessing the mechanical properties of soft tissues, is a potential noninvasive diagnostic method to assess hepatic fibrosis. In this work, MRE was evaluated as a quantitative method to assess the in vivo mechanical properties of the liver tissues in a knockout animal model of liver fibrosis. This work demonstrates that the shear stiffness of liver tissue increases systematically with the extent of hepatic fibrosis, as measured by histology. A linear correlation between liver stiffness and fibrosis extent was well-defined in this animal model. An additional finding of the study was that fat infiltration, commonly present in chronic liver disease, does not significantly correlate with liver stiffness at each fibrosis stage and thus does not appear to interfere with the ability of MRE to assess fibrosis extent. In conclusion, MRE has the potential not only for assessing liver stiffness, but also for monitoring potential therapies for hepatic fibrosis.

FibroMAX: towards a new universal biomarker of liver disease?

Among the noninvasive alternatives to liver biopsy, several studies have demonstrated the predictive value and a better benefit-to-risk ratio than biopsy of five combinations of simple serum biochemical markers (the super combination being FibroMAX (BioPredictive, Paris, France) in patients at risk of chronic liver diseases: FibroTest (BioPredictive) for the quantitative assessment of fibrosis; SteatoTest (BioPredictive) for the quantitative assessment of steatosis; ActiTest (BioPredictive) for the quantitative assessment of necroinflammatory activity in chronic viral hepatitis C and B; NashTest (BioPredictive) for the categorical diagnosis of nonalcoholic steatohepatitis; and AshTest for the quantitative assessment of alcoholic steatohepatitis (also known in the USA as HCV-FibroSURE, HBV-FibroSURE, ASH-FibroSURE and NASH-FibroSURE; LabCorp, NC, USA). The possible causes of false-negative and false-positive results are also better identified. These tests, which are now available in 50 countries, can facilitate the screening and management of the most frequent liver diseases.

Assessment of hepatic fibrosis with magnetic resonance elastography

BACKGROUND & AIMS

Accurate detection of hepatic fibrosis is crucial for assessing prognosis and candidacy for treatment in patients with chronic liver disease. Magnetic resonance (MR) elastography, a technique for quantitatively assessing the mechanical properties of soft tissues, has been shown previously to have potential for noninvasively detecting liver fibrosis. The goal of this work was to obtain preliminary estimates of the sensitivity and specificity of the technique in diagnosing liver fibrosis, and to assess its potential for identifying patients who potentially can avoid a biopsy procedure.

METHODS

MR elastography was performed in 35 normal volunteers and 50 patients with chronic liver disease. MR imaging measurements of hepatic fat to water ratios were obtained to assess the potential for fat infiltration to affect stiffness-based detection of fibrosis.

RESULTS

Liver stiffness increased systematically with fibrosis stage. Receiver operating curve analysis showed that, with a shear stiffness cut-off value of 2.93 kilopascals, the predicted sensitivity and specificity for detecting all grades of liver fibrosis is 98% and 99%, respectively. Receiver operating curve analysis also provided evidence that MR elastography can discriminate between patients with moderate and severe fibrosis (grades 2-4) and those with mild fibrosis (sensitivity, 86%; specificity, 85%). Hepatic stiffness does not appear to be influenced by the degree of steatosis.

CONCLUSIONS

MR elastography is a safe, noninvasive technique with excellent diagnostic accuracy for assessing hepatic fibrosis. Based on the high negative predictive value of MR elastography, an initial clinical application may be to triage patients who are under consideration for biopsy examination to assess possible hepatic fibrosis.

Noninvasive diagnosis of hepatic fibrosis in chronic hepatitis C

Assessment of hepatic fibrosis is important for determining prognosis, guiding management decisions, and monitoring disease. Histological evaluation of liver biopsy specimens is currently considered the reference test for staging hepatic fibrosis. Since liver biopsy carries a small but significant risk, noninvasive tests to assess hepatic fibrosis are desirable. This editorial gives an overview on noninvasive methods currently available to determine hepatic fibrosis and their diagnostic accuracy for predicting significant fibrosis and cirrhosis in chronic hepatitis C. Based on available data, the performance of simple tests derived from routine laboratory parameters appears to be similar to that of more complex and expensive fibrosis panels. Transient elastography seems more accurate than blood tests for diagnosing cirrhosis.

Hepatic imaging characteristics predict overall survival in hepatocellular carcinoma

BACKGROUND

Pathologic tumor-related factors, including vascular invasion, remain the only reliable predictor of recurrence and overall survival in hepatocellular cancer (HCC). Other preoperative factors, such as hepatitis status, degree of liver disease (cirrhosis), number of tumors, and size of tumors have been inconsistent in predicting outcome. The aim of this study is to demonstrate that standard radiological imaging characteristics will predict overall survival in HCC.

METHODS

We identified 103 HCC treated in our department from January 1999 to June 2005. All images were reviewed by two blinded physicians and classified into one of three radiological characteristics: pusher/mass forming (well encapsulated without parenchymal violation), invader (non-encapsulated with violation of parenchyma), and hanger/pedunculated (encapsulated with a majority of the lesion suspended from segments II, III, IV b, V, and / or VI).

RESULTS

The study included 61 males and 31 females with a median age of 61 years (range 23 to 90 years), a median of one lesion (range 1-10), a majority with <25% liver involvement, with a median lesion size of 6 cm (range 1 to 22 cm). Surgical therapy included hepatic resection 34 (33%), RFA 23 (22%), and liver transplantation 21 (20%). The distribution of radiological characteristics at initial evaluation was 54% pushers, 41% invaders, and 4% hangers. Median survival for invaders (8.2 months) and hangers (10.0 months) was significantly lower than for pushers (median 29 months) (p = 0.0007).

CONCLUSION

Standard, reproducible radiological characteristics are predictive of outcome in patients with HCC. Greater emphasis on identifying preoperative factors remains imperative to better identify patients' biology and determine which should undergo resection or transplantation.