Julie Parkes

Noninvasive markers of fibrosis in nonalcoholic fatty liver disease: Validating the European Liver Fibrosis Panel and exploring simple markers

The detection of fibrosis within nonalcoholic fatty liver disease (NAFLD) is important for ascertaining prognosis and the stratification of patients for emerging therapeutic intervention. We validated the Original European Liver Fibrosis panel (OELF) and a simplified algorithm not containing age, the Enhanced Liver fibrosis panel (ELF), in an independent cohort of patients with NAFLD. Furthermore, we explored whether the addition of simple markers to the existing panel test could improve diagnostic performance. One hundred ninety‐six consecutively recruited patients from 2 centers were included in the validation study. The diagnostic accuracy of the discriminant scores of the ELF panel, simple markers, and a combined panel were compared using receiver operator curves, predictive values, and a clinical utility model. The ELF panel had an area under the curve (AUC) of 0.90 for distinguishing severe fibrosis, 0.82 for moderate fibrosis, and 0.76 for no fibrosis. Simplification of the algorithm by removing age did not alter diagnostic performance. Addition of simple markers to the panel improved diagnostic performance with AUCs of 0.98, 0.93, and 0.84 for the detection of severe fibrosis, moderate fibrosis, and no fibrosis, respectively. The clinical utility model showed that 82% and 88% of liver biopsies could be potentially avoided for the diagnosis of severe fibrosis using ELF and the combined panel, respectively. The ELF panel has good diagnostic accuracy in an independent validation cohort of patients with NAFLD. The addition of established simple markers augments the diagnostic performance across different stages of fibrosis, which will potentially allow superior stratification of patients with NAFLD for emerging therapeutic strategies. (HEPATOLOGY 2007.)

Enhanced liver fibrosis test can predict clinical outcomes in patients with chronic liver disease

Background Clinicians use fibrosis in a liver biopsy to predict clinical outcomes of chronic liver disease. The performance of non-invasive tests has been evaluated against histological assessment of fibrosis but use of clinical outcomes as the reference standard would be ideal. The enhanced liver fibrosis (ELF) test was derived and validated in a large cohort of patients and shown to have high diagnostic accuracy (area under the curve (AUC)=0.80 95% CI 0.76 to 0.85) in identification of significant fibrosis on biopsy. Objective To evaluate ELF performance in predicting clinical outcomes by following up the original ELF cohort. Methods Patients recruited to the ELF study at seven English centres were followed up for liver morbidity and mortality by examination of clinical data. Defaulting/discharged patients were followed up by family practitioner questionnaires. Primary outcome measure was liver-related morbidity/liver-related death. Results 457 patients were followed up (median 7 years), with ascertainment of clinical status in 92%. There were 61 liver-related outcomes (39 deaths). Survival analysis showed that the ELF score predicts liver outcomes, with people having the highest ELF scores being significantly more likely to have clinical outcomes than those in lower-score groups. A Cox proportional hazards model showed fully adjusted HRs of 75 (ELF score 12.52–16.67), 20 (10.426–12.51) and 5 (8.34–10.425) compared with patients with ELF <8.34. A unit change in ELF is associated with a doubling of risk of liver-related outcome. Conclusions An ELF test can predict clinical outcomes in patients with chronic liver disease and may be a useful prognostic tool in clinical practice.

Historical epidemiology of hepatitis C virus (HCV) in selected countries

Chronic infection with hepatitis C virus (HCV) is a leading indicator for liver disease. New treatment options are becoming available, and there is a need to characterize the epidemiology and disease burden of HCV. Data for prevalence, viremia, genotype, diagnosis and treatment were obtained through literature searches and expert consensus for 16 countries. For some countries, data from centralized registries were used to estimate diagnosis and treatment rates. Data for the number of liver transplants and the proportion attributable to HCV were obtained from centralized databases. Viremic prevalence estimates varied widely between countries, ranging from 0.3% in Austria, England and Germany to 8.5% in Egypt. The largest viremic populations were in Egypt, with 6 358 000 cases in 2008 and Brazil with 2 106 000 cases in 2007. The age distribution of cases differed between countries. In most countries, prevalence rates were higher among males, reflecting higher rates of injection drug use. Diagnosis, treatment and transplant levels also differed considerably between countries. Reliable estimates characterizing HCV‐infected populations are critical for addressing HCV‐related morbidity and mortality. There is a need to quantify the burden of chronic HCV infection at the national level.

Prediction of clinical outcomes in primary biliary cirrhosis by serum enhanced liver fibrosis assay

Primary biliary cirrhosis (PBC) is sometimes diagnosed based on a positive antimitochondrial antibody in the appropriate clinical setting without a liver biopsy. Although a liver biopsy can assess the extent of liver fibrosis and provide prognostic information, serum fibrosis markers avoid biopsy complications and sampling error and provide results as a continuous variable, which may be more precise than categorical histological stages. The current study was undertaken to evaluate serum fibrosis markers as predictors of clinical progression in a large cohort of PBC patients. Serial liver biopsy specimens and serum samples were collected every 2 years in 161 PBC subjects for a median of 7.3 years. Clinical progression was defined as development of one or more of the following events: varices, variceal bleed, ascites, encephalopathy, liver transplantation, or liver‐related death. Serum hyaluronic acid, tissue inhibitor of metalloproteinase 1, and procollagen III aminopeptide were measured and entered into the previously validated enhanced liver fibrosis (ELF) algorithm. The ability of ELF, histological fibrosis, bilirubin, Model for End‐Stage Liver Disease (MELD), and Mayo Risk Score to differentiate between individuals who would experience a clinical event from those who would not was evaluated at different time points. Event‐free survival was significantly lower in those with high baseline ELF. Each 1‐point increase in ELF was associated with a threefold increase in future complications. The prognostic performance of all tests was similar when performed close to the time of the first event. However, at earlier times in the disease process (4 and 6 years before the first event), the prognostic performance of ELF was significantly better than MELD or Mayo R score. Conclusion: The ELF algorithm is a highly accurate noninvasive measure of PBC disease severity that provides useful long‐term prognostic information. (HEPATOLOGY 2008.)

Strategies to manage hepatitis C virus (HCV) disease burden

The number of hepatitis C virus (HCV) infections is projected to decline while those with advanced liver disease will increase. A modeling approach was used to forecast two treatment scenarios: (i) the impact of increased treatment efficacy while keeping the number of treated patients constant and (ii) increasing efficacy and treatment rate. This analysis suggests that successful diagnosis and treatment of a small proportion of patients can contribute significantly to the reduction of disease burden in the countries studied. The largest reduction in HCV‐related morbidity and mortality occurs when increased treatment is combined with higher efficacy therapies, generally in combination with increased diagnosis. With a treatment rate of approximately 10%, this analysis suggests it is possible to achieve elimination of HCV (defined as a >90% decline in total infections by 2030). However, for most countries presented, this will require a 3–5 fold increase in diagnosis and/or treatment. Thus, building the public health and clinical provider capacity for improved diagnosis and treatment will be critical.

Enhanced Liver Fibrosis (ELF) test accurately identifies liver fibrosis in patients with chronic hepatitis C

Summary.  Assessment of liver fibrosis is important in determining prognosis and evaluating interventions. Due to limitations of accuracy and patient hazard of liver biopsy, non‐invasive methods have been sought to provide information on liver fibrosis, including the European liver fibrosis (ELF) test, shown to have good diagnostic accuracy for the detection of moderate and severe fibrosis. Access to independent cohorts of patients has provided an opportunity to explore if this test could be simplified. This paper reports the simplification of the ELF test and its ability to identity severity of liver fibrosis in external validation studies in patients with chronic hepatitis C (CHC). Paired biopsy and serum samples from 347 naïve patients with CHC in three independent cohorts were analysed. Diagnostic performance characteristics were derived (AUROC, sensitivity and specificity, predictive values), and clinical utility modelling performed to determine the proportion of biopsies that could have been avoided if ELF test was used in this patient group. It was possible to simplify the original ELF test without loss of performance and the new algorithm is reported. The simplified ELF test was able to predict severe fibrosis [pooled AUROC of 0.85 (95% CI 0.81–0.89)] and using clinical utility modelling to predict severe fibrosis (Ishak stages 4–6; METAVIR stages 3 and 4) 81% of biopsies could have been avoided (65% correctly). Issues of spectrum effect in diagnostic test evaluations are discussed. In chronic hepatitis C a simplified ELF test can detect severe liver fibrosis with good accuracy.

Comparison of ELF, FibroTest and FibroScan for the non-invasive assessment of liver fibrosis

BackgroundFibroTest (FT) is the most frequently used serum fibrosis marker and consists of an algorithm of five fibrosis markers (alfa2-macroglobulin, apolipoproteinA1, haptoglobin, GGT, bilirubin). The Enhanced Liver Fibrosis (ELF) test consists of an algorithm of three fibrosis markers (hyaluronic acid, amino-terminal propeptide-of-type-III-collagen, tissue-inhibitor of matrix-metaloproteinase-1). While a systematic review has shown comparable results for both individual markers, there has been no direct comparison of both markers.MethodsIn the present study, the ELF-test was analyzed retrospectively in patients with chronic liver disease, who received a liver biopsy, transient elastography (TE) and the FibroTest using histology as the reference method. Histology was classified according to METAVIR and the Ludwigs classification (F0-F4) for patients with chronic hepatitis C and B virus (HCV, HBV) infection and primary biliary cirrhosis (PBC), respectively.ResultsSeventy-four patients were analysed: 36 with HCV, 10 with HBV, and 28 with PBC. The accuracy (AUROC) for the diagnosis of significant fibrosis (F≥2) for ELF and FibroTest was 0.78 (95%CI:0.67-0.89) and 0.69 (95%-CI:0.57-0.82), respectively (difference not statistically significant, n.s.). The AUROC for the diagnosis of liver cirrhosis was 0.92 (95%CI:0.83-1,00), and 0.91 (95%CI:0.83-0.99), respectively (n.s.). For 66 patients with reliable TE measurements the AUROC for the diagnosis of significant fibrosis (cirrhosis) for TE, ELF and FT were 0.80 (0.94), 0.76 (0.92), and 0.67 (0.91), respectively (n.s.).ConclusionFibroTest and ELF can be performed with comparable diagnostic accuracy for the non-invasive staging of liver fibrosis. Serum tests are informative in a higher proportion of patients than transient elastography.

Predicted effects of treatment for HCV infection vary among European countries.

BACKGROUND & AIMS The dynamics of hepatitis C virus (HCV) infection, as well as screening practices and access to therapy, vary among European countries. It is important to determine the magnitude of the effects of such differences on incidence and mortality of infection. We compared the dynamics of infection and screening and treatment practices among Belgium, France, Germany, Italy, Spain, and the United Kingdom. We also assessed the effects of treatment with pegylated interferon and additional effects of triple therapy with protease inhibitors. METHODS We created a country-specific Markov model of HCV progression based on published epidemiologic data (on HCV prevalence, screening, genotype, alcohol consumption among patients, and treatments) and reports of competitive and hepatocellular carcinoma mortality for the 6 countries. The model was used to predict the incidence of HCV-related cirrhosis and its mortality until 2021 for each country. RESULTS From 2002 to 2011, antiviral therapy reduced the cumulative incidence of cirrhosis by 7.1% and deaths by 3.4% overall. Reductions in incidence and mortality values ranged from 4.0% and 1.9%, respectively, in Italy to 16.3% and 9.0%, respectively, in France. From 2012 to 2021, antiviral treatment of patients with HCV genotype 1 infection that includes protease inhibitor-based triple therapy will reduce the cumulative incidence of cirrhosis by 17.7% and mortality by 9.7% overall. The smallest reduction is predicted for Italy (incidence reduced by 10.1% and mortality by 5.4%) and the highest is for France (reductions of 34.3% and 20.7%, respectively). CONCLUSIONS Although HCV infection is treated with the same therapies in different countries, the effects of the therapies on morbidity and mortality vary significantly. In addition to common guidelines that are based on virologic response-guided therapy, there is a need for public health policies based on population-guided therapy.

Evaluation of a prison outreach clinic for the diagnosis and prevention of hepatitis C: implications for the national strategy

Background: Hepatitis C virus (HCV) infection is a major public health problem recognised by the UK National Strategy that proposes that a care pathway for assessment, diagnosis, and treatment be established in all prisons, integrated within managed clinical networks. A prison sentence provides the opportunity to focus on traditionally hard to reach patients. Aims: To evaluate the prevalence of HCV infection in a UK prison cluster and to assess the effectiveness of a prison outreach service for hepatitis C. Subjects: Male prisoners. Methods: A nurse specialist led clinic within a cluster of adult prisons was established, offering health education on hepatitis C, advice on harm minimisation, and HCV testing. Infected prisoners were offered access to a care pathway leading to treatment. Outcome measures were uptake of the service, and diagnosis and treatment of hepatitis C. Results: A total of 8.5% of 1618 prisoners accepted testing: 30% had active infection with HCV. Most were ineligible for treatment due to psychiatric illness or did not receive treatment for logistic reasons. Injecting drug use was the major risk factor in all cases. Only 7% of HCV polymerase chain amplification positive inmates received treatment in prison. Conclusion: There is a large pool of HCV infected prisoners at risk of complications, constituting a source of infection during their sentence and after discharge. A prison outreach clinic and care pathway was perceived as effective in delivering health education, reducing the burden on prison and hospital services. It provided an opportunity for intervention but had a limited effect in eradicating HCV in prisoners and it remains unclear how this might be achieved.

Validation of terminal peptide of procollagen III for the detection and assessment of nonalcoholic steatohepatitis in patients with nonalcoholic fatty liver disease

Liver biopsy is the reference standard for the detection of nonalcoholic steatohepatitis (NASH) within nonalcoholic fatty liver disease (NAFLD). The aim of this study was to identify a biomarker of NASH in patients without significant fibrosis. In all, 172 patients from two centers with biopsy‐proven NAFLD were included in this study. Eighty‐four patients from a single center were included as a derivation cohort and 88 patients from a second center were included as a validation cohort. Serum samples were tested for candidate markers of fibrosis and inflammation alongside hematological and biochemical markers. Among patients without advanced fibrosis, terminal peptide of procollagen III (PIIINP) was the only marker found to be associated with a histological diagnosis of NASH in both cohorts. PIIINP also correlated with the total NAFLD activity score (NAS) and its constituent components (P < 0.001). Area under receiver operating characteristic curve (AUROC) for PIIINP in discriminating between NASH and simple steatosis (SS) was 0.77‐0.82 in patients with F0‐2 fibrosis and 0.82‐0.84 in patients with F0‐3 fibrosis. PIIINP was elevated in patients with advanced fibrosis, the overwhelming majority of whom had NASH. When incorporating patients with all degrees of fibrosis from both cohorts, PIIINP was able to discriminate between patients with SS and those with NASH or advanced fibrosis with AUROC 0.85‐0.87. Conclusion: PIIINP discriminates between SS and NASH or advanced fibrosis. The use of a single biomarker in this context will be of clinical utility in detecting the minority of patients with NAFLD who have NASH or advanced fibrosis related to NASH. (HEPATOLOGY 2013)