Comparison of the liver stiffness measurement by transient elastography with the liver biopsy

Associations of Real-Time Ultrasound and Strain and Shear Wave Elastography with Gastrointestinal Organs: A Systematic Review

Ultrasound elastography is gaining attention for its diagnostic potential across various medical fields, and its physical properties make it valuable in modern clinical medicine. However, its specific attributes, especially in the context of recent medical advancements, remain relatively unexplored. This study aimed to identify instrument-specific characteristics and applications of real-time ultrasound elastography, shear wave elastography, and strain elastography, particularly within gastroenterology. Following PRISMA guidelines, the study examined elastography articles on databases like PubMed, resulting in 78 included articles. Data on patient demographics, organ involvement, specificity, sensitivity, accuracy, positive predictive value, and negative predictive value were extracted. Statistical analysis involved SPSS version 21, with significance set at p < 0.05. The majority of patients were male (50.50%), with a mean age of 42.73 ± 4.41 years. Shear wave elastography was the most prevalent technique (48.7%), and liver investigations were predominant in gastroenterology (34.6%). Gastrointestinal applications showed higher sensitivity, positive predictive value, and negative predictive values (p < 0.05) but lower specificity (p < 0.05). Real-time ultrasound elastography exhibited increased specificity, accuracy, and predictive values (p < 0.05). Ultrasound elastography appears more accurate and effective in gastroenterological settings. Nonetheless, its performance depends on instrument-specific and operator-dependent factors. While promising, further studies are necessary to ascertain optimal utilization in both gastrointestinal and non-gastrointestinal conditions.

Diagnostic accuracy of apparent diffusion coefficient values combined with γ-glutamyl transpeptidase-to-platelet ratio parameters for predicting hepatitis B-related fibrosis

OBJECTIVES

The accuracy of non-invasive liver fibrosis diagnosis based on the apparent diffusion coefficient (ADC) value combined with the γ-glutamyl transpeptidase-to-platelet ratio (GPR) model to predict the stage of hepatitis B-related fibrosis has not been reported. This study aimed to evaluate the diagnostic efficacy of ADC value combined with GPR for liver fibrosis grading.

METHODS

The data of 180 patients with chronic hepatitis B (CHB) diagnosed by liver biopsy were analyzed. The ADC value, GPR, and their combination were assessed in different cirrhosis stages using receiver operating characteristic curve analysis to evaluate their value in diagnosing liver fibrosis.

RESULTS

We observed that liver fibrosis stages were inversely associated with ADC values (r=-0.691, P<0.001), and positively associated with GPR (r=0.502, P<0.001). The area under the curve for diagnostic efficacy of ADC values, GPR, and their combination for F≥2 liver fibrosis was 0.831, 0.749, and 0.858, respectively, and for F≥3 was 0.872, 0.771, and 0.903, respectively. The diagnostic cutoffs of the combination for each stage were -7.07, -12.21 and -37.75, respectively.

CONCLUSIONS

The combined diagnostic tool of ADC and GPR may improve the accuracy of hepatitis B-related liver fibrosis diagnosis, especially for F≥3.

Hepcidin-to-ferritin ratio: A potential novel index to predict iron overload-liver fibrosis in ß-thalassemia major

OBJECTIVES

We aimed to determine a threshold cutoff for hepcidin, ferritin, and the hepcidin-to-ferritin ratio in the diagnosis of liver fibrosis caused by iron overload in chronic hepatitis C virus (HCV)-free ß-thalassemia major patients .

METHODS

This 1:1-matched case-control study included 102 individuals (3-30 yr.); 51 ß-thalassemia major patients with iron overload , and 51 apparently healthy individuals.

RESULTS

The highest areas under the receiver operating characteristic curves (AUC-ROCs) for the diagnosis of patients vs. controls had overlapping 95% confidence intervals (CIs): serum hepcidin (0.758; 0.64-0.87; P ˂ 0.001), serum ferritin (1.000; 1.00-1.00; P˂0.001), and the hepcidin/ferritin ratio (1.000; 1.00-1.00; P˂0.001). For differentiation of patients with liver fibrosis stages of F0-F1 vs. F2-F4 and F0-F1 vs. F3-F4, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) with P-values˂0.001 were the only statistically significant parameters, while the AUC-ROCs of the hepcidin/ferritin ratio (0.631, P=0.188 and 0.684, P=0.098) exhibited 90% and 89.5% sensitivity, respectively, in staging liver fibrosis.

CONCLUSION

Our results showed that the hepcidin/ferritin ratio is as effective as the APRI and maybe a better predictor for the diagnosis of liver fibrosis and discriminating its stages, with excellent sensitivity and specificity compared to its components.

Noninvasive Assessment of Hepatitis C Virus Infected Patients Using Vibration-Controlled Transient Elastography

Chronic infection with hepatitis C virus (HCV) is one of the leading causes of cirrhosis and hepatocellular carcinoma (HCC). Surveillance of these patients is an essential strategy in the prevention chain, including in the pre/post-antiviral treatment states. Ultrasound elastography techniques are emerging as key methods in the assessment of liver diseases, with a number of advantages such as their rapid, noninvasive, and cost-effective characters. The present paper critically reviews the performance of vibration-controlled transient elastography (VCTE) in the assessment of HCV patients. VCTE measures liver stiffness (LS) and the ultrasonic attenuation through the embedded controlled attenuation parameter (CAP), providing the clinician with a tool for assessing fibrosis, cirrhosis, and steatosis in a noninvasive manner. Moreover, standardized LS values enable proper staging of the underlying fibrosis, leading to an accurate identification of a subset of HCV patients that present a high risk for complications. In addition, VCTE is a valuable technique in evaluating liver fibrosis prior to HCV therapy. However, its applicability in monitoring fibrosis regression after HCV eradication is currently limited and further studies should focus on extending the boundaries of VCTE in this context. From a different perspective, VCTE may be effective in identifying clinically significant portal hypertension (CSPH). An emerging prospect of clinical significance that warrants further study is the identification of esophageal varices. Our opinion is that the advantages of VCTE currently outweigh those of other surveillance methods.

Hepatic and splenic sonographic and sonoelastographic findings in pulmonary arterial hypertension

Purpose

The aim of this study was to evaluate the associations of sonographic and sonoelastographic parameters with clinical cardiac parameters, as well as to assess their value in predicting survival in patients with pulmonary arterial hypertension (PAH).

Methods

Thirty-six patients with PAH and normal liver function were prospectively enrolled in this prospective study along with 26 healthy controls, all of whom underwent ultrasound and point shear wave elastography examinations. Additionally, the portal vein pulsatility index (PVPI), inferior vena cava collapsibility index, and clinical cardiac variables were obtained in PAH patients. The values of hepatic (LV_s) and splenic shear wave velocity (SV_s) were compared between PAH patients and controls. The relationships between all sonographic and clinical parameters in the PAH patients were analyzed. Furthermore, their prognostic value in predicting survival was investigated.

Results

LV_s values in PAH patients (median, 1.62 m/s) were significantly higher than in controls (median, 0.99 m/s), while no significant difference was observed in SV_s values. Patients with higher grades of tricuspid regurgitation (TR) had significantly different values of PVPI (P=0.010) and sonoelastographic parameters (P<0.001 for LV_s and P=0.004 for SV_s) compared to those with less severe TR. Tricuspid annular plane systolic excursion values were the only investigated parameter found to be associated with survival (hazard ratio, 0.814; 95% confidence interval, 0.694 to 0.954; P=0.011).

Conclusion

Our results demonstrated a direct association between cardiac congestion (i.e., the severity of TR) and liver stiffness, which should be kept in mind during the assessment of fibrosis in patients with PAH.

The effect of a Mediterranean diet on metabolic parameters in patients with non-alcoholic fatty liver disease: A systematic review of randomized controlled trials

BACKGROUND

Dietary habit can play a key role in the prevention and treatment of fatty liver disease (NAFLD). Although many studies have investigated the effect of Mediterranean diet on NAFLD, findings are inconsistent and there is no systematic review on this topic. Therefore, the aim of this systematic review is to summarize the effect of Mediterranean diet on serum metabolic indices and anthropometric measures among NAFLD patients.

METHODS

We searched titles, abstracts, and keywords of articles indexed in Science Direct, MEDLINE, and Google Scholar databases up to October 2018 to identify eligible RCT studies. Randomized clinical trials assessing the effects of MD on NAFLD were included.

RESULTS

The present study included 10 randomized controlled trials, which involved a total of 856 adults with NAFLD. According to the result, MD may improve anthropometric measures, lipid profile, glycemic indices, liver enzyme, and NAFLD severity indices among patients with NAFLD.

CONCLUSION

We found that MD could alleviate NAFLD severity parameters but differences between studies should be taken into account. Finally, in order to draw a firm link between MD and NAFLD, more clinical trials with adequate sample size and better methodology should be done.

Deciphering host immunity to malaria using systems immunology

A century of conceptual and technological advances in infectious disease research has changed the face of medicine. However, there remains a lack of effective interventions and a poor understanding of host immunity to the most significant and complex pathogens, including malaria. The development of successful interventions against such intractable diseases requires a comprehensive understanding of host-pathogen immune responses. A major advance of the past decade has been a paradigm switch in thinking from the contemporary reductionist (gene-by-gene or protein-by-protein) view to a more holistic (whole organism) view. Also, a recognition that host-pathogen immunity is composed of complex, dynamic interactions of cellular and molecular components and networks that cannot be represented by any individual component in isolation. Systems immunology integrates the field of immunology with omics technologies and computational sciences to comprehensively interrogate the immune response at a systems level. Herein, we describe the system immunology toolkit and report recent studies deploying systems-level approaches in the context of natural exposure to malaria or controlled human malaria infection. We contribute our perspective on the potential of systems immunity for the rational design and development of effective interventions to improve global public health.

Pentraxin 3 Detects Clinically Significant Fibrosis in Patients with Chronic Viral Hepatitis C

Pentraxin 3 (PTX3) plays a pathogenic role in experimental models of chronic liver injury and contributes to the progression of fibrosis. The detection of advanced fibrosis (METAVIR F≥3) is important to identify patients who are in urgent need of antiviral treatments versus those whose treatment could be deferred (F≥2). The aim was to assess the diagnostic value of PTX3 as a potential biomarker for clinically significant and advanced fibrosis. PTX3 associations with biochemical and histological parameters of inflammatory activity and fibrosis were investigated in 138 patients with chronic viral hepatitis C (HCV) before antiviral treatment. METAVIR histological scores of activity and fibrosis were obtained. PTX3 was measured by enzyme-linked immunosorbent assay. The diagnostic accuracy of serum PTX3 levels was compared to that of other fibrosis markers, including transforming growth factor‐β₁ (TGF-β₁), hyaluronic acid (HA), aspartate transaminase to platelet ratio index (APRI), fibrosis score based on four factors (FIB4), gamma-glutamyltranspeptidase to platelet ratio (GPR), and the liver stiffness measurement (LSM) by transient elastography (FibroScan®). In HCV patients the PTX3 level increased in parallel with the METAVIR histological score of activity, being independently associated with the METAVIR fibrosis score (P < 0.001). Using the receiver operating characteristics analysis, the best marker for detecting F≥2 and F≥3 was PTX3 with AUC = 0.802 and AUC = 0.867, respectively. The area under the curve of PTX3 for predicting significant fibrosis (F≥2) was significantly greater than those for the GPR ratio (AUC = 0.648) and FIB-4 score (AUC = 0.770) and similar to that for APRI index (AUC = 0.831). PTX3 provided clinically relevant diagnostic accuracy as a single marker of significant fibrosis.

Non-invasive in vivo Imaging Grading of Liver Fibrosis

Liver fibrosis (LF), a common consequence of chronic liver diseases with various etiologies, is characterized by excessive accumulation of macromolecules, including collagen, glycoproteins and proteoglycans, in the liver. LF can result in hepatic dysfunction, cirrhosis, portal hypertension and, in some cases, hepatocellular carcinoma. As the current gold standard for diagnosing LF, liver biopsy, however, is invasive and prone to sampling errors and procedure-related complications. Therefore, developing noninvasive, precise and reproducible imaging tests for diagnosing and staging LF is of great significance. Conventional ultrasound (US), computed tomography (CT) and magnetic resonance (MR) imaging can depict morphological alterations of advanced LF, but have relatively limited capability characterizing early-stage LF. In order to optimize the diagnostic performances of noninvasive imaging techniques for LF across its entire spectrum of severity, a number of novel methods, including US elastography, CT perfusion imaging and various MR imaging-based techniques, have been established and introduced to clinical practice. In this review, we intended to summarize current noninvasive imaging techniques for LF, with special emphasis on the possible roles, advantages and limitations of the new emerging imaging modalities.

Changes in liver stiffness and steatosis among patients with hepatitis C virus infection who received direct-acting antiviral therapy and achieved sustained virological response

AIM

Whether direct-acting antiviral (DAA) therapy can reduce liver fibrosis and steatosis in patients with chronic hepatitis C virus (HCV) infection remains unclear. We evaluated sequential changes in liver stiffness and steatosis using transient elastography (TE) and the TE-based controlled attenuation parameter (CAP) in patients with HCV who received DAA therapy.

PATIENTS AND METHODS

A total of 57 patients with HCV who received DAA therapy and achieved sustained virological response (SVR) were analyzed. Liver stiffness as evaluated with TE, steatosis as evaluated with CAP, and laboratory data were assessed before treatment (baseline), at end of treatment (EOT), 24 weeks after EOT (SVR24), and 48 weeks after EOT (SVR48).

RESULTS

Alanine aminotransferase levels, corresponding to the presence of necroinflammatory activity, significantly decreased overall, with significant differences between baseline and EOT, EOT, and SVR24, and baseline and SVR48. However, alanine aminotransferase levels showed no significant changes between SVR24 and SVR48. Median (interquartile range) liver stiffness values at baseline, EOT, SVR24, and SVR48 were 8.3 (5.0-14.8), 7.4 (4.6-14.7), 5.3 (4.1-11.8), and 5.4 (4.0-13.4) kPa, respectively (baseline vs. EOT, P=0.044; EOT vs. SVR24, P=0.011; and SVR24 vs. SVR48, P=0.054). In patients with fatty liver (CAP≥236 dB/m, n=14), CAP values at baseline and SVR48 were 253 (245-278) and 229 (209-249) dB/m, respectively (P=0.020).

CONCLUSION

Liver stiffness at SVR24 might reflect liver fibrosis in the patients who received DAA therapy and achieved SVR. In addition, liver steatosis reduces in the same cohort with fatty liver.

Effect of Meal Ingestion on Liver Stiffness and Controlled Attenuation Parameter

Background and Aims

Despite the increasing use of noninvasive methods for the assessment of liver fibrosis and steatosis, the effect of fasting and food intake on these parameters is not yet clear. Our aims were to evaluate the effect of food intake on liver stiffness (LS) (measured by transient elastography) and controlled attenuation parameter (CAP) in patients with different degrees of liver disease and healthy volunteers, and secondarily, to assess possible factors associated with variations of LS and CAP.

Methods

We performed a prospective single-center study including patients with liver disease and healthy volunteers. LS and CAP were evaluated using FibroScan® (Echosens, Paris, France), before (fasting ≥8 h) and 30 min after intake of a standardized breakfast. We used common cutoffs for LS: > 7 kPa for significant fibrosis (F2 to F4) and > 11 to 14 kPa (mean 12.5 kPa) for cirrhosis.

Results

Fifty-nine (72%) patients with liver disease and 22 (28%) healthy volunteers were included. LS significantly increased 30 min after food intake (pre-meal 6.1 kPa [IQR: 4.7-9.8] vs. after-meal 6.8 kPa [IQR: 5.5-10.6]; p < 0.001). This difference was only significant in patients with chronic liver disease (p = 0.02) and not in healthy volunteers (p = 0.106). CAP values did not increase significantly after food intake. Gender, body mass index, mass of body fat, lean body mass, and percent of body fat were not related with significant variations of LS and CAP values after meal intake.

Conclusions

Significant variations of LS were observed after ingestion of a standard meal, which may have consequences for patient management. CAP values were not significantly affected by food intake. Therefore, we consider that before the isolated evaluation of CAP, it is not necessary to perform any fasting period.

The Clinical Difference in the Platelet Counts between Liver Cirrhosis with Nonalcoholic Fatty Liver Disease and Hepatitis C Virus

Objective The rate of platelet count reduction appears to differ among different liver diseases. In the present study, we investigated the difference in the platelet counts of patients with nonalcoholic fatty liver disease (NAFLD) and those with chronic liver disease due to hepatitis C virus (CLD-HCV). Methods The study population included 620 patients with NAFLD and 405 patients with CLD-HCV, all of whom were diagnosed by liver biopsy. The relationships between the grade of fibrosis and the platelet count in the two diseases were compared. The optimal cut-off value for the diagnosis of liver cirrhosis (LC) was measured. The relationships between the platelet count and anti-platelet antibodies, the serum thrombopoietin level, the grade of splenomegaly and liver stiffness were also investigated in both LC groups. Results In NAFLD patients, the platelet count was significantly higher at each grade of fibrosis in comparison to CLD-HCV. The optimal cut-off value for the diagnosis of LC was 16.0×10⁴/μL [sensitivity, 86.7%; specificity, 87.6%; area under the curve (AUC), 0.930] in NAFLD and 12.7×10⁴/μL (sensitivity, 57.8%; specificity, 88.2%; AUC, 0.863) in CLD-HCV. No anti-platelet antibodies were detected in patients with either type of LC. The serum thrombopoietin levels, the distribution of splenomegaly grades, and liver stiffness did not differ between the two LC groups to a statistically significant extent. As the splenomegaly grade increased, the platelet count decreased. Conclusion The optimal cut-off values for diagnosing LC differed between the two diseases and should be determined separately. The reason for the difference in platelet reduction is still unclear, and requires further investigation.

Sustained virological response halts fibrosis progression: A long-term follow-up study of people with chronic hepatitis C infection

BACKGROUND/AIMS

Long-term follow-up studies validating the clinical benefit of sustained virological response (SVR) in people with chronic hepatitis C (CHC) infection are lacking. Our aim was to identify rates and predictors of liver fibrosis progression in a large, well characterized cohort of CHC patients in whom paired liver fibrosis assessments were performed more than 10 years apart.

METHODS

CHC patients who had undergone a baseline liver biopsy pre-2004 and a follow up liver fibrosis assessment more than 10 years later (biopsy or liver stiffness measurement (LSM) using transient elastography [FibroScan]) were identified. Subjects who had undergone a baseline liver biopsy but had no follow up fibrosis assessment were recalled for LSM. Fibrosis was categorised as mild-moderate (METAVIR F0-2 / LSM result of ≤ 9.5 kPa) or advanced (METAVIR F3-4/ LSM >9.5 kPa). The primary objective was to assess the association between SVR and the rate of liver fibrosis progression over at least 10 years, defined as an increase from mild-moderate fibrosis at baseline liver biopsy (METAVIR F0-2) to advanced fibrosis at follow-up liver fibrosis assessment.

RESULTS

131 subjects were included in this analysis: 69% male, 82% Caucasian, 60% G1 HCV, 25% G3 HCV. The median age at F/U fibrosis staging was 57 (IQR 54-62) years with median estimated duration of infection 33-years (IQR 29-38). At F/U, liver fibrosis assessment was performed by LSM in 86% and liver biopsy in 14%. The median period between fibrosis assessments was 14-years (IQR 12-17). 109 (83%) participants had received interferon-based antiviral therapy. 40% attained SVR. At F/U, there was a significant increase in the proportion of subjects with advanced liver fibrosis: 27% at baseline vs. 46% at F/U (p = 0.002). The prevalence of advanced fibrosis did not change among subjects who attained SVR, 30% at B/L vs 25% at F/U (p = 0.343). However, advanced fibrosis became more common at F/U among subjects with persistent viremia: 10% at B/L vs 31% at F/U (p = 0.0001). SVR was independently associated with protection from liver fibrosis progression after adjustment for other variables including baseline ALT (p = 0.011), duration of HCV infection and mode of acquisition.

CONCLUSION

HCV eradication is associated with lower rates of liver fibrosis progression. The data support early treatment to prevent long-term liver complications of HCV infection.

Liver acoustic radiation force impulse (ARFI) in childhood obesity: comparison and correlation with biochemical markers

PURPOSE

To compare and correlate the diagnostic efficiency of acoustic radiation force impulse (ARFI) elastography with biochemical markers for assessing hepatic changes in overweight and obese children.

METHODS

This prospective study was approved by the institutional ethics committee. It included 54 overweight and obese children and 50 normal children (as a control group) in the age range 5-18 years. For all children, we performed grayscale ultrasonography to diagnose fatty liver, ARFI elastography to measure liver stiffness, and biochemical evaluation for aspartate aminotransferase (AST), alanine aminotransferase (ALT), and serum triglyceride (TG) levels.

RESULTS

Of the 54 obese children, AST was elevated in 13 (24.1%) and ALT was elevated in 16 (29.6%); however, only 4 (25%) of these 16 obese children with abnormal aminotransferase levels had an AST/ALT ratio >0.8. Furthermore, all children with abnormal aminotransferase levels with AST/ALT ratio >0.8 also had abnormal readings of ARFI elastography. The TG was elevated (>150 mg/dL) in 2 out of 54 (3.7%) obese children. None of the normal children showed abnormal levels of aminotransferase and TG. Three out of 54 (5.6%) obese children did not show fatty liver changes, while 29 (53.7%) showed grade-I fatty liver changes, and 22 (40.7%) showed grade-II fatty liver changes. The mean (SD) ARFI value was 1.13 m/s (SD 0.199) for obese children and 1.02 m/s (SD 0.11) for children in the control group. Of the 54 obese children, 49 (90.7%) showed ARFI values of <1.19 m/s (normal), 4 (7.4%) had ARFI values from >1.19 to <1.75 m/s, and 1 (1.9%) had an ARFI value >1.75 m/s. Four children with an increased ARFI value also had an AST/ALT ratio >0.8. However, one obese child with a raised ARFI value did not have an elevated AST/ALT ratio, and none of his aminotransferase levels were abnormal. All normal children had ARFI values <1.19 m/s.

CONCLUSION

ARFI elastography shows excellent correlation with AST/ALT ratios in obese children and may be used as a noninvasive tool to detect nonalcoholic fatty liver disease (NAFLD) and associated hepatic changes, especially in pediatric patients, for whom liver biopsy is not always feasible.

Non-invasive diagnosis of hepatitis B virus-related cirrhosis

Chronic hepatitis B (CHB)-related cirrhosis is a major threat to public health, and about 23% of patients with CHB progress naturally to liver cirrhosis. Worldwide, about 650000 people die each year from various complications caused by CHB. liver cirrhosis has become a global concern. Progressive hepatic fibrosis can lead to cirrhosis, and early diagnosis of liver fibrosis is fundamental. Staging fibrosis is critical for the prognosis evaluation and management of patients with liver diseases. Liver biopsy is the reference standard for assessment of liver fibrosis. However, this method is invasive, and is associated with pain and complications that can be fatal, which leads to the progress of non-invasive assessment based on serological and imaging techniques. These non-invasive assessments have been shown to be effective in the diagnosis of liver fibrosis. This article mainly introduces the principle, clinical application, diagnostic efficacy, and limitations of non-invasive assessments for hepatitis B virus-related fibrosis.

Impact of Cytomegalovirus Infection on Severe Hepatitis C Recurrence in Patients Undergoing Liver Transplantation

BACKGROUND

The influence of cytomegalovirus (CMV) on recurrent hepatitis C virus (HCV) in liver grafts is controversial. Our aim was to investigate the association between CMV infection and disease and severe HCV recurrence (composite variable of presence of stage 3 to 4 fibrosis, need for retransplantation or death due to liver disease) in the first year after transplantation.

METHODS

An observational, prospective, multicenter study was performed. The CMV replication was monitored by determining CMV viral load weekly during hospitalization after transplantation, twice monthly in the first 3 months after discharge, and at each follow-up visit until month 12. Liver fibrosis was assessed histologically by liver biopsy or transient elastometry. Pretransplant, intraoperative, and posttransplant variables were recorded. Multiple logistic regression was performed to study the impact of CMV on severe HCV recurrence.

RESULTS

Ninety-eight patients were included. The CMV infection was detected in 48 patients (49%) in the first year posttransplant, of which 11 patients (22.9%) had CMV disease. Twenty-three patients (23.5%) had severe HCV recurrence. Of these, 17 (73.9%) developed stage 3 to 4 fibrosis, 4 (17.4%) died, and 2 (8.7%) underwent retransplantation. Only 7 of 12 (58.3%) seronegative recipients of a seropositive donor (positive donor/negative recipient [D+/R-]) received universal prophylaxis, and 10 of 12 (83.3%) D+/R- patients developed CMV replication. In the multivariate analysis, the presence of CMV D+/R- serodiscordance (odds ratio, 6.87; 95% confidence interval, 1.89-24.99; P = 0.003), and detection of a higher peak HCV viral load (odds ratio, 3.85; 95% confidence interval, 1.49-9.94; P = 0.005) were associated with severe HCV recurrence.

CONCLUSIONS

Our results support an association between CMV D+/R- serodiscordance and severe HCV recurrence in patients undergoing liver transplantation for HCV liver disease.

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.

Cost-effectiveness of non-invasive methods for assessment and monitoring of liver fibrosis and cirrhosis in patients with chronic liver disease: systematic review and economic evaluation

BACKGROUND

Liver biopsy is the reference standard for diagnosing the extent of fibrosis in chronic liver disease; however, it is invasive, with the potential for serious complications. Alternatives to biopsy include non-invasive liver tests (NILTs); however, the cost-effectiveness of these needs to be established.

OBJECTIVE

To assess the diagnostic accuracy and cost-effectiveness of NILTs in patients with chronic liver disease.

DATA SOURCES

We searched various databases from 1998 to April 2012, recent conference proceedings and reference lists.

METHODS

We included studies that assessed the diagnostic accuracy of NILTs using liver biopsy as the reference standard. Diagnostic studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Meta-analysis was conducted using the bivariate random-effects model with correlation between sensitivity and specificity (whenever possible). Decision models were used to evaluate the cost-effectiveness of the NILTs. Expected costs were estimated using a NHS perspective and health outcomes were measured as quality-adjusted life-years (QALYs). Markov models were developed to estimate long-term costs and QALYs following testing, and antiviral treatment where indicated, for chronic hepatitis B (HBV) and chronic hepatitis C (HCV). NILTs were compared with each other, sequential testing strategies, biopsy and strategies including no testing. For alcoholic liver disease (ALD), we assessed the cost-effectiveness of NILTs in the context of potentially increasing abstinence from alcohol. Owing to a lack of data and treatments specifically for fibrosis in patients with non-alcoholic fatty liver disease (NAFLD), the analysis was limited to an incremental cost per correct diagnosis. An analysis of NILTs to identify patients with cirrhosis for increased monitoring was also conducted.

RESULTS

Given a cost-effectiveness threshold of £20,000 per QALY, treating everyone with HCV without prior testing was cost-effective with an incremental cost-effectiveness ratio (ICER) of £9204. This was robust in most sensitivity analyses but sensitive to the extent of treatment benefit for patients with mild fibrosis. For HBV [hepatitis B e antigen (HBeAg)-negative)] this strategy had an ICER of £28,137, which was cost-effective only if the upper bound of the standard UK cost-effectiveness threshold range (£30,000) is acceptable. For HBeAg-positive disease, two NILTs applied sequentially (hyaluronic acid and magnetic resonance elastography) were cost-effective at a £20,000 threshold (ICER: £19,612); however, the results were highly uncertain, with several test strategies having similar expected outcomes and costs. For patients with ALD, liver biopsy was the cost-effective strategy, with an ICER of £822.

LIMITATIONS

A substantial number of tests had only one study from which diagnostic accuracy was derived; therefore, there is a high risk of bias. Most NILTs did not have validated cut-offs for diagnosis of specific fibrosis stages. The findings of the ALD model were dependent on assuptions about abstinence rates assumptions and the modelling approach for NAFLD was hindered by the lack of evidence on clinically effective treatments.

CONCLUSIONS

Treating everyone without NILTs is cost-effective for patients with HCV, but only for HBeAg-negative if the higher cost-effectiveness threshold is appropriate. For HBeAg-positive, two NILTs applied sequentially were cost-effective but highly uncertain. Further evidence for treatment effectiveness is required for ALD and NAFLD.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42011001561.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

A health technology assessment of transient elastography in adult liver disease

BACKGROUND

An estimated one in 10 Canadians have some form of liver disease. The reference standard for staging and monitoring liver fibrosis is percutaneous liver biopsy--an invasive procedure associated with risks and complications. Transient elastography (TE) represents a noninvasive, ultrasound-based alternative.

OBJECTIVE

To assess the efficacy of TE compared with liver biopsy for fibrosis staging in adults with five common types of liver disease: hepatitis B, hepatitis C, nonalcoholic fatty liver disease, cholestatic liver disease and complications post-liver transplantation.

METHODS

A systematic review of published and grey literature from 2001 to June 2011 was conducted. Included were observational studies evaluating the accuracy of TE using liver biopsy as the comparator. An economic model was developed to estimate the cost per correct diagnosis gained with liver biopsy compared with TE. Identification of moderate fibrosis (stages 2 to 4) and cirrhosis (stage 4) were considered.

RESULTS

Fifty-seven studies were included in the review. The diagnostic accuracy of TE for the five clinical subgroups had sensitivities ranging from 0.67 to 0.92 and specificities ranging from 0.72 to 0.95. Liver biopsy was associated with an additional $1,427 to $7,030 per correct diagnosis gained compared with TE. The model was sensitive to the sensitivity and specificity of TE and the prevalence of fibrosis.

CONCLUSIONS

TE is an accurate diagnostic method in patients with moderate fibrosis or cirrhosis. TE is less effective but less expensive than liver biopsy. Systemic implementation of TE should be considered for the noninvasive assessment of liver fibrosis.

Evaluation of hepatic fibrosis stage (≥ F2) by fibroscan in patients with chronic viral hepatitis: A Meta-analysis

AIM: To evaluate the value of fibroscan (FS) in hepatic fibrosis stage assessment in patients with chronic viral hepatitis, and to examine whether its accuracy is affected by etiology.

METHODS: English and Chinese articles related to assessment of hepatic fibrosis stage by fibroscan in Wanfang, Chinese Journal Full-Text Database (CJFD), Chinese Biomedical Literature Database (CBM), PubMed, Cochrane library and EMBASE database were strictly screened and evaluated. Data of enrolled articles were analyzed using Meta-disc1.4 and Stata12.0 software.

RESULTS: A total of 28 English and Chinese articles were included. The pooled sensitivity, specificity, diagnostic odds ratio and the area under curve (AUC) of summary receiver operating characteristic (SROC) curve for significant fibrosis (F ≥ 2) and cirrhosis (F = 4) in patients with chronic viral hepatitis were 0.72 (0.70-0.73), 0.85 (0.83-0.87), 18.51 (13.28-25.80), 0.88 and 0.86 (0.84-0.88), 0.86 (0.85-0.87), 49.14 (30.53-79.09) and 0.94, respectively. There was no significant difference among the results of meta-analysis according to etiology.

CONCLUSION: Fibroscan has a high diagnostic accuracy for evaluating hepatic fibrosis stage, especially in patients with cirrhosis. The diagnostic accuracy of fibroscan is not affected by etiology.

Role of fibroscan and APRI in detection of liver fibrosis: a systematic review and meta-analysis

BACKGROUND AND STUDY AIMS

Fibroscan and APRI are promising noninvasive alternatives to liver biopsy for detecting hepatic fibrosis. However, their overall test performance in various settings remains questionable. The aim of our study was to perform a systematic review and meta-analysis of diagnostic accuracy studies comparing fibroscan and APRI with liver biopsy for hepatic fibrosis.

PATIENTS AND METHODS

Electronic and manual bibliographic searches to identify potential studies were performed. Selection of studies was based on reported accuracy of fibroscan and APRI compared with liver biopsy. Data extraction was performed independently by two reviewers. Meta-analysis combined the sensitivities, specificities, and likelihood ratios of individual studies. Extent and reasons for heterogeneity were assessed.

RESULTS

23 studies for fibroscan and 20 studies for APRI in full publication were identified. For patients with stage IV fibrosis (cirrhosis), the pooled estimates for sensitivity of fibroscan were 83.4% (95% confidence interval [CI], 71.7-95.0%) and specificity 92.4% (95% CI, 85.6-99.2%). For patients with stage IV fibrosis (cirrhosis), the pooled estimates for sensitivity of APRI at cutoff point of 1.5 were 66.5% (95% CI, 25.0-100%) and specificity 71.7% (95% CI, 35.0-100%). Diagnostic threshold bias was identified as an important cause of heterogeneity for pooled results in both patient groups.

CONCLUSIONS

Fibroscan and APRI appear to be clinically useful tests for detecting cirrhosis however not useful tools in early stages of fibrosis.

Acoustic radiation force elasticity imaging in diagnostic ultrasound

The development of ultrasound-based elasticity imaging methods has been the focus of intense research activity since the mid-1990s. In characterizing the mechanical properties of soft tissues, these techniques image an entirely new subset of tissue properties that cannot be derived with conventional ultrasound techniques. Clinically, tissue elasticity is known to be associated with pathological condition and with the ability to image these features in vivo; elasticity imaging methods may prove to be invaluable tools for the diagnosis and/or monitoring of disease. This review focuses on ultrasound-based elasticity imaging methods that generate an acoustic radiation force to induce tissue displacements. These methods can be performed noninvasively during routine exams to provide either qualitative or quantitative metrics of tissue elasticity. A brief overview of soft tissue mechanics relevant to elasticity imaging is provided, including a derivation of acoustic radiation force, and an overview of the various acoustic radiation force elasticity imaging methods.

Experimental mechanical characterization of abdominal organs: liver, kidney & spleen

Abdominal organs are the most vulnerable body parts during vehicle trauma, leading to high mortality rate due to acute injuries of liver, kidney, spleen and other abdominal organs. Accurate mechanical properties and FE models of these organs are required for simulating the traumas, so that better designing of the accident environment can be done and the organs can be protected from severe damage. Also from biomedical aspect, accurate mechanical properties of organs are required for better designing of surgical tools and virtual surgery environments. In this study porcine liver, kidney and spleen tissues are studied in vitro and hyper-elastic material laws are provided for each. 12 porcine kidneys are used to perform 40 elongation tests on renal capsule and 60 compression tests on renal cortex, 5 porcine livers are used to perform 45 static compression tests on liver parenchyma and 5 porcine spleens are used to carry out 20 compression tests. All the tests are carried out at a static speed of 0.05 mm/s. A comparative analysis of all the results is done with the literature and though the results are of same order of magnitude, a slight dissonance is observed for the renal capsule. It is also observed that the spleen is the least stiff organ in the abdomen whereas the kidney is the stiffest. The results of this study would be essential to develop the FE models of liver, kidney and spleen which can be further used for impact biomechanical and biomedical applications.

Correlation between liver stiffness measurement by Fibroscan and liver fibrosis staging based on a liver biopsy in patients with NAFLD

AIM: To evaluate the role of Fibroscan (FS) in the diagnosis of liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD).

METHODS: A total of 83 patients who were pathologically diagnosed with NAFLD and underwent liver stiffness measurement using FibroScan at Beijing Youan Hospital from April 2008 to February 2011 were included in this study. Staging of liver fibrosis based on a liver biopsy was performed in all patients. Other clinical tests included liver function, FBG, blood lipids and UA The correlation between liver stiffness and liver fibrosis degree was analyzed. The receive operating characteristic (ROC) curve was used to analyze the accuracy of Fibroscan in diagnosing liver fibrosis with NAFLD.

RESULTS: The liver stiffness differed among patients with different stages of liver fibrosis. The Fibroscan values were 4.28 kPa ± 1.32 kPa, 7.40 kPa ± 2.13 kPa, 11.52 kPa ± 3.86 kPa, and 19.99 kPa ± 5.42 kPa for patients with S0 to S3 liver fibrosis, respectively, and liver stiffness was closely related to stage of liver fibrosis (r = 0.768, P < 0.001). Fibroscan score was positively correlated with ALT and AST, but negatively with HDL and ApoA (all P < 0.05). The area under the ROC curve for FibroScan score in assessing liver fibrosis was 0.889 (0.813, 0.965) in patients with S1 liver fibrosis, 0.838 (0.729, 0.948) in those with S2, and 0.938 (0.000, 1.000) in those with S3. The cut off values were 8.95 kPa, 10.60 kPa and 15.66 kPa, respectively.

CONCLUSION: Fibroscan is valuable for the diagnosis of liver fibrosis in patients with NAFLD.

Serial changes of liver stiffness measured by acoustic radiation force impulse imaging in acute liver failure: a case report

Acoustic radiation force impulse (ARFI) imaging is a new technology used to determine liver elasticity. We report the case of a patient that survived hyperacute-type acute liver failure (ALF) and who showed a dramatic change in the value of shear wave velocity (SWV) measured by ARFI, which corresponded with the severity of her liver damage. The value of SWV increased significantly up to 3.6 ± 0.3 m/s during the encephalopathy phase and then decreased along with the recovery of liver function, the blood flow of the right portal vein, and the liver volume. These findings suggest the value of SWV in ALF as a reliable marker of liver tissue damage. Further investigations of the pathophysiological significance of SWV in ALF are warranted.

Is ultrasound elastography of the liver ready to replace biopsy? A critical review of the current techniques

Accurate assessment of liver fibrosis in patients with chronic liver disease is necessary to determine prognosis, monitor disease progression and formulate treatment decisions. Currently, histological staging of liver biopsy is the most widely used reference standard for this purpose. Liver biopsy, however, has recognized risks, as well as sampling and observer error. These limitations have stimulated the search for new non-invasive approaches. Numerous methodologies, including serum markers, magnetic resonance elastography and ultrasound elastography, have evolved in the last decade to predict fibrosis in those with chronic liver disease. Ultrasound elastography methods assess liver fibrosis by determining liver stiffness and translate this into a quantifiable measurement for analysis. As these tests are non-invasive, without side-effect or discomfort, it is possible to conduct repeat examinations at much closer intervals than biopsy. The three most investigated ultrasound elastography methods are transient elastography, realtime elastography and acoustic radiation force impulse. Although significant strides have been made in the development of the technology, an unequivocal advocacy of elastography as a surrogate for biopsy is still not established. The aim of this review is to evaluate the advantages, limitations and clinical relevance of the three ultrasound-based modalities. Also, the review shall assess the current and possible future clinical application the modalities may serve both separate and in conjunction with liver biopsy.

Reduction of liver stiffness by antiviral therapy in chronic hepatitis B

BACKGROUND

Liver stiffness (LS) has been reported to correlate with fibrosis stage (F). The correlation between LS and fibrosis stage and the reduction of LS by antiviral therapy were examined in patients with hepatitis B infection.

METHODS

LS was measured by FibroScan in 212 patients infected with hepatitis B virus. Liver biopsies were done in 51 patients. Changes of LS were assessed in 29 patients treated with nucleotide or nucleoside analogs and 52 patients without antiviral therapy.

RESULTS

LS was significantly correlated with fibrosis stage (ρ = 0.686, P < 0.0001). The optimal cut-off values of LS were 7.1 kPa for F ≥ 2, 10.7 kPa for F ≥ 3, and 16.0 kPa for F4. LS was significantly reduced by antiviral therapy, from 12.9 (range 6.2-17.9) kPa to 6.6 (4.4-10.3) kPa measured at an interval of 512 (range 366-728) days (P < 0.0001). Eleven of 19 (58%) patients with baseline fibrosis stages of F3-4 deduced from LS had 2-point or greater reductions of deduced stage at the last LS measurement. The change ratio of hyaluronic acid (P = 0.0390) was associated with a 2-point or greater reduction of deduced fibrosis stage. Without antiviral therapy, LS tended to increase, increasing from 6.1 (range 3.9-8.5) kPa to 6.3 (range 4.4-9.7) kPa at an interval of 422 (range 358-709) days (P = 0.0682).

CONCLUSIONS

LS was significantly correlated with fibrosis stage in patients with chronic hepatitis B. The reduction of LS by antiviral therapy was significantly correlated with the reduction of hyaluronic acid. Thus, we conclude that LS can be useful to assess the progression and regression of liver fibrosis stage noninvasively.

How efficient is acoustic radiation force impulse elastography for the evaluation of liver stiffness?

BACKGROUND

In chronic liver diseases, a correct estimation of the severity of liver fibrosis is important for recommendations regarding the treatment. Nowadays, evaluation of fibrosis is done by noninvasive methods such as biochemical scores and transient elastography instead of liver biopsy. The lack of sensitivity to detect fibrosis, because of its heterogeneity is a drawback of liver biopsy (LB).

OBJECTIVES

To compare transient elastography (TE) and acoustic radiation force impulse (ARFI) for the evaluation of liver stiffness (LS), against percutaneous LB.

PATIENTS AND METHODS

Our study comprised of 223 subjects; 52 without fibrosis (38 volunteers and 14 patients with F0 on LB), 36 with F1, 40 with F2, 26 with F3 and 69 with liver cirrhosis (46 with LB and 23 with signs of cirrhosis). For each patient we performed in the same session 10 TE and 5 ARFI measurements. The median values were calculated.

RESULTS

A strong linear correlation (Spearman rho = 0.870) was found between TE and fibrosis (P < 0.0001); there was also a weaker correlation between ARFI and fibrosis (Spearman rho = 0.646; P < 0.0001). TE measurements were also correlated with ARFI measurements (Spearman rho = 0.733, P < 0.0001). The best test for predicting significant fibrosis (F ≥ 2) was TE with a cut-off value of 7.1 kPa (AUROC 0.953). For ARFI, the cut-off value was 1.27 m/s-area under ROC curve (AUROC): 0.890, sensitivity (Se) of 88.7%, specificity (Sp) of 67.5%, positive predictive value (PPV) of 64.5%, and negative predictive value (NPV) of 90% (P = 0.0044). For predicting cirrhosis (F = 4), the optimum cut-off values were 14.4 kPa for TE (AUROC: 0.985, Se: 95.6%, Sp: 94.7%, PPV: 89.2%, NPV: 98%) and 1.7 m/s for ARFI (AUROC: 0.931, Se: 93%, Sp: 86.7%, PPV: 73.6%, NPV: 96.9%) (P = 0.0102).

CONCLUSIONS

LS evaluation by means of ARFI is not superior to TE for the assessment of liver fibrosis. ARFI is an accurate test for the diagnosis of cirrhosis.

Elastography for the diagnosis of severity of fibrosis in chronic liver disease: a meta-analysis of diagnostic accuracy

BACKGROUND & AIMS

Transient elastography is a non-invasive method, for the assessment of hepatic fibrosis, developed as an alternative to liver biopsy. We studied the performance of elastography for diagnosis of fibrosis using meta-analysis.

METHODS

MEDLINE, EMBASE, SCI, Cochrane Library, conference abstracts books, and article references were searched. We included studies using biopsy as a reference standard, with the data necessary to calculate the true and false positive, true and false negative diagnostic results of elastography for a fibrosis stage, and with a 3-month maximum interval between tests. The quality of the studies was rated with the QUADAS tool.

RESULTS

We identified 40 eligible studies. Summary sensitivity and specificity was 0.79 (95% CI 0.74-0.82) and 0.78 (95% CI 0.72-0.83) for F2 stage and 0.83 (95% CI 0.79-0.86) and 0.89 (95% CI 0.87-0.91) for cirrhosis. After an elastography result at/over the threshold value for F2 or cirrhosis ("positive" result), the corresponding post-test probability for their presence (if pre-test probability was 50%) was 78%, and 88% respectively, while, if values were below these thresholds ("negative" result), the post-test probability was 21% and 16%, respectively. No optimal stiffness cut-offs for individual fibrosis stages were validated in independent cohorts and cut-offs had a wide range and overlap within and between stages.

CONCLUSIONS

Elastography theoretically has good sensitivity and specificity for cirrhosis (and less for lesser degrees of fibrosis); however, it should be cautiously applied to everyday clinical practice because there is no validation of the stiffness cut-offs for the various stages. Such validation is required before elastography is considered sufficiently accurate for non-invasive staging of fibrosis.

Non-invasive assessment of liver fibrosis in chronic hepatitis C

Quantification of hepatic fibrosis is of critical importance in chronic hepatitis C not only for prognosis, but also for antiviral treatment indication. Two end points are clinically relevant: detection of significant fibrosis (indication for antiviral treatment) and detection of cirrhosis (screening for eosphageal varices and hepatocellular carcinoma). Until recently, liver biopsy was considered the reference method for the evaluation of liver fibrosis. Limitations of liver biopsy (invasiveness, sampling error, and inter-observer variability) have led to the development of non-invasive methods. Currently available methods rely on two different approaches: a "biological" approach based on the dosage of serum fibrosis biomarkers; and a "physical" approach based on the measurement of liver stiffness, using transient elastography (TE). This review is aimed at discussing the advantages and limits of non-invasive methods and liver biopsy and the perspectives for their rational use in clinical practice in the management of patients with chronic hepatitis C.

The Diagnostic Value of Ultrasound Elastography in Patients with Hepatitis B Virus Infection: A Prospective Study

The aim of this prospective study was to investigate the diagnostic value of ultrasound elastography for evaluating liver stiffness measurement (LSM) in 74 patients with hepatitis B virus (HBV) infection, treated with telbivudine (22 with chronic HBV infection, 32 with compensated cirrhosis and 20 with decompensated cirrhosis). Each patient underwent ultrasound elastography measurements and serum liver marker assays before and after 6 months' treatment with 600 mg telbivudine, orally, once daily. In the 22 patients with chronic HBV infection, LSM values measured by ultrasound elastography decreased significantly following the treatment period compared with baseline. The LSM values were significantly higher in the 20 patients with decompensated cirrhosis than in the 32 patients with compensated cirrhosis after treatment. Significant decreases in serum hepatic fibrosis indices occurred in all patients following treatment. The correlation between fibrosis index, hyaluronic acid level and LSM was statistically significant in all patients, whereas the correlation between alanine aminotransferase and LSM was not. The findings suggest that liver stiffness in patients with HBV can be measured simply with ultrasound elastography and that it is reduced within 6 months by treatment with telbivudine. The main adverse events noted during the study period were that creatine kinase levels were increased in seven patients and that seven patients had influenza-like symptoms.

Liver stiffness measurements in patients with HBV vs HCV chronic hepatitis: A comparative study

AIM: To assess the values of liver stiffness (LS) in patients with hepatitis B virus (HBV) chronic hepatitis and to compare them with those in patients with hepatitis C virus (HCV) chronic hepatitis.

METHODS: The study included 140 patients with HBV chronic hepatitis, and 317 patients with HCV chronic hepatitis, in which LS was measured (FibroScan^®-Echosens^®) and liver biopsy was performed in the same session (assessed according to the Metavir score).

RESULTS: According to the Metavir score of the 140 HBV patients: one had F0, 32 had F1, 67 had F2, 33 had F3 and 7 had F4. Of the 317 HCV patients: 5 had F0, 34 had F1, 146 had F2, 93 had F3 and 39 had F4. For the same severity of fibrosis, the mean values of LS in HBV patients were similar to those in HCV patients: F1, 6.5 ± 1.9 kPa vs 5.8 ± 2.1 kPa (P = 0.0889); F2, 7.1 ± 2 kPa vs 6.9 ± 2.5 kPa (P = 0.3369); F3, 9.1 ± 3.6 kPa vs 9.9 ± 5 kPa (P = 0.7038); F4, 19.8 ± 8.6 kPa vs 17.3 ± 6.1 kPa (P = 0.6574). A significant direct correlation between LS measurements and fibrosis was found in HCV patients (Spearman’s r = 0.578, P < 0.0001), as well as in HBV patients (r = 0.408, P < 0.0001). The correlation was more significant in HCV than in HBV patients (Fisher’s Z-test, Z = 2.210, P = 0.0271).

CONCLUSION: In our group, the mean values of LS in patients with chronic B hepatitis were similar to those in patients with chronic HCV hepatitis, for the same stage of fibrosis. Also, LS was correlated with the severity of fibrosis both in HBV and HCV chronic hepatitis patients.

Ultrasonic elastography in clinical quantitative assessment of fatty liver

AIM: To investigate the clinical application of ultrasonic elastography in quantitative assessment of fatty liver grading.

METHODS: A total of 105 patients with fatty liver were divided into mild group (n = 46), moderate group (n = 39), and severe group (n = 20). Forty-five healthy individuals served as a normal control group. All patients who underwent routine ultrasound scan and further ultrasonic elastography were evaluated accordingly to the evaluation standards for ultrasonic elastography. The ratio of surface areas of blue region/total surface area in the desired region was measured.

RESULTS: Ultrasonic elastography technique, in comparison to traditional ultrasound, had a rather high consistence in grading of fatty liver [κ value = (95.3%-63.6%)/(1%-63.6%) = 0.87, P = 0.001]. The score of ultrasonic elastography increased with the severity of fatty liver with a sensitivity of 97.14% and a specificity of 91.11%. A significant difference was found in the ratio of surface areas of blue regions between different groups (P < 0.05).

CONCLUSION: Ultrasonic elastography can be used in quantitative assessment of the severity of fatty liver.

Food intake increases liver stiffness in patients with chronic or resolved hepatitis C virus infection

BACKGROUND AND AIMS

Transient elastography is increasingly being used in patients with chronic liver disease. It has proven particularly useful to identify patients with advanced fibrosis or cirrhosis, while classification of no or little fibrosis appears to be difficult. In general, stiffness values <6 kPa are considered normal, whereas patients with higher levels are candidates for a disease-specific treatment or further diagnostic evaluation. Parameters influencing liver stiffness may include food intake that increases liver blood flow.

METHODS

In a pilot study, transient elastography was performed in eight patients with chronic hepatitis C at fasting and serially for 180 min after intake of a standardized breakfast. Confirmatory, 56 patients and 19 controls underwent liver stiffness determination at fasting, directly after meal intake and 1 h after breakfast.

RESULTS

Liver stiffness significantly increased immediately after food intake for up to 60 min (P=0.01) before normalizing after 180 min. An intraindividual analysis showed a significant increase in 22 out of 43 patients with an initial liver stiffness <or=10 kPa. An increase of at least 1 kPa after food intake was found in 24 out of 43 (56%) patients with initial stiffness <or=10 kPa. Notably, nine out of 23 (39%) patients with normal initial liver stiffness (<6 kPa) had a value of >6 kPa after food intake, potentially leading to unnecessary treatment or diagnostic procedures.

CONCLUSION

Food intake increases liver stiffness in patients with hepatitis C virus infection and healthy controls. To standardize liver stiffness evaluation, we suggest measurement in the fasting condition.