Normal enhanced liver fibrosis (ELF) values in apparently healthy subjects undergoing a health check-up and in living liver donors in South Korea

Analytical performance of the Enhanced Liver Fibrosis (ELF) Test on the Atellica IM Analyzer

BACKGROUND

The Enhanced Liver Fibrosis (ELFTM) Test comprises 3 direct serum markers of fibrosis-hyaluronic acid (HA), amino-terminal pro-peptide of type III procollagen (PIIINP), and tissue inhibitor of matrix metalloproteinase 1 (TIMP-1)-whose results are combined in an algorithm to generate the ELF score. Outside the U.S., the ELF Test and score are CE marked for assessment of liver fibrosis severity in patients with signs, symptoms, or risk factors of chronic liver disease to support diagnosis of fibrosis staging or prognosis for likelihood of progression to cirrhosis and liver-related clinical events. In the U.S., the FDA granted de novo marketing authorization to aid prognostic evaluation of disease progression (to cirrhosis and liver-related clinical events) in nonalcoholic steatohepatitis patients with advanced liver fibrosis. We describe the analytical performance of the ELF analytes and score on the Atellica® IM Analyzer.

METHODS

Clinical and Laboratory Standards Institute protocols were followed for detection capability (limits of blank [LoB], detection [LoD], and quantitation [LoQ]), precision, interference, linearity, hook effect, and ELF reference interval.

RESULTS

All parameters met predetermined requirements: HA (LoB 1.00 ng/mL, LoD 2.00 ng/mL, LoQ 3.00 ng/mL); PIIINP (LoB 0.50 ng/mL, LoD 0.75 ng/mL, LoQ 1.00 ng/mL); TIMP-1 (LoB 3.0 ng/mL, LoD 4.0 ng/mL, LoQ 5.0 ng/mL). Across the 3 assays, repeatability was ≤5.4% CV; within-lab precision was ≤8.5% CV. ELF score repeatability was ≤0.6% CV, within-lab precision ≤1.3% CV, and reproducibility ≤1.1% CV. Good correlation was obtained between the Atellica IM ELF and ADVIA Centaur ELF Tests (y = 1.01x - 0.22, r = 0.997). Assays were linear across analytical measuring ranges.

CONCLUSIONS

Analytical performance validation results for the ELF Test and ELF score were excellent making the test acceptable for routine clinical use.

Noninvasive surrogates are poor predictors of liver fibrosis in patients with Fontan circulation

OBJECTIVES

Patients with Fontan circulation exhibit a high incidence of liver fibrosis and cirrhosis. Transient elastography (TE) and the enhanced liver fibrosis (ELF) test have proven useful as noninvasive surrogate markers of liver fibrosis for other chronic liver diseases. We evaluated whether TE and the ELF score can predict the degree of liver fibrosis in patients with Fontan circulation.

METHODS

We retrospectively reviewed the medical records of 45 adult patients with at least 10 years of Fontan duration who had undergone liver biopsy and investigated the relation between the fibrosis stage and TE and the ELF test results. Additionally, the association of these variables and other biochemical and hemodynamic parameters was assessed.

RESULTS

The mean age was 25.9 years and the mean Fontan duration was 20.8 years. Advanced liver fibrosis was present in 36 (80.0%) patients. TE or ELF score are comparable for patients with and without advanced liver fibrosis (mean 23.3 vs 24.8 kPa [P = .85] for TE; mean 8.94 vs 9.25 [P = .44] for the ELF score). However, N-terminal pro-brain natriuretic peptide level and ventricular end-diastolic pressure were higher in patients with advanced liver fibrosis (mean 224 vs 80 pg/mL [P < .01]; and mean 12 vs 9 mm Hg [P = .04], respectively). No independent predictor of advanced liver fibrosis was found in multivariate analysis.

CONCLUSIONS

TE and the ELF score were unable to predict the degree of liver fibrosis in Fontan patients. Liver biopsy remains as the only valid method to assess fibrotic burden in this population.

Enhanced Liver Fibrosis Score: Is It Useful for Evaluation of Fibrosis Severity in Chronic Hepatitis C Infection?

Introduction: The assessment of liver fibrosis is important in patients with chronic hepatitis C (CHC). In recent years, non-invasive tests like enhanced liver fibrosis (ELF) have been developed as an alternative to liver biopsy for estimating the severity of liver fibrosis. Therefore, we aimed to assess whether the ELF score can be used for fibrosis severity estimation using liver biopsy as the gold standard.

Materials and methods: Forty-nine patients with CHC were enrolled in this study. Liver biopsy, ELF assessment, and transient elastography (TE) were performed in all patients, and severity of fibrosis on histopathology was assessed by meta-analysis of histological data in viral hepatitis (METAVIR) score. In addition, the diagnostic performance of ELF was evaluated by receiver operator characteristic curve (ROC) analyses, and liver biopsy histopathology was taken as the gold standard for the severity of liver fibrosis.

Results: The area under receiver operator characteristic curve (AUROC) for significant fibrosis of ELF score was 0.64 (95% confidence interval {CI}, 0.48-0.79) and of TE was 0.85 (95% CI, 0.73-0.96). The AUROC for advance fibrosis of ELF was 0.77 (95% CI, 0.57-0.97) and TE was 0.98 (95% CI, 0.94-1.0). The calculated cut-offs of ELF overestimated fibrosis in 53.06% (26/49) of patients and underestimated fibrosis in 6.12% (3/49) patients. AUROC of TE was significantly better than ELF for diagnosis of significant fibrosis (p=0.004) and advanced fibrosis (p=0.034).

Conclusion: The ELF score can be used for estimating the severity of fibrosis but it is inferior to TE in estimating liver fibrosis severity.

The Enhanced Liver Fibrosis test is associated with liver-related outcomes in postmenopausal women with risk factors for liver disease

BACKGROUND

Chronic liver disease (CLD) is usually asymptomatic but earlier detection is critical to permit life-saving interventions for those at risk due to high alcohol consumption and increased body mass index (BMI). The aim of this study was to estimate the association between the Enhanced Liver Fibrosis (ELF) test and liver-related events (LRE) and its performance in predicting LRE in postmenopausal women with risk factors in a nested case-control study within the United Kingdom Trial of Ovarian Cancer Screening (UKCTOCS).

METHODS

In a cohort of 95,126 we performed a case-control study measuring ELF in blinded samples from 173 participants with self-reported high alcohol use and / or BMI ≥25 kg/m2 comprising all 58 cases who developed LRE and 115 controls matched for age, alcohol and BMI who did not develop LRE during median follow-up of 8.5 years.

RESULTS

Using Cox regression at an ELF threshold of 10.51 hazard ratios (HR) for LRE were 4.88 (95% confidence interval (CI) 2.37-10.03) (unadjusted model) and 4.62 (95% CI 2.12-10.08) (adjusted for deprivation and self-reported hypertension, heart disease, hypercholesterolaemia and diabetes). At a threshold of 9.8 HR for LRE were 2.21 (95% CI 1.22-3.97) (unadjusted model) and 2.18 (95% CI 1.19-4.01) (adjusted). ELF was evaluated as a time dependent variable by generating time-dependent Cox models; HRs at an ELF threshold of 10.51 were 1.94 (95% CI 1.10-3.39) (unadjusted) and 2.05 (95% CI 1.16-3.64) (adjusted) and at a threshold of 9.8 HRs were 1.85 (95% CI 1.09-3.15) (unadjusted) and 1.80 (95% CI 1.04-3.13) (adjusted). Area under the receiver operating characteristic curve for recruitment ELF predicting LRE was 0.58 (95% CI 0.49-0.68), and for second subsequent ELF 0.61 (95% CI 0.52-0.71).

CONCLUSION

This study demonstrates the association between ELF and CLD in postmenopausal women with risk factors for liver disease, creating the opportunity to intervene to reduce liver-related mortality and morbidity. Although larger studies are required, these results demonstrate the potential of ELF as a prognostic tool in health checks in primary care.

TRIAL REGISTRATION

This study is nested in UKCTOCS. UKCTOCS is registered as an International Standard Randomised Controlled Trial, number ISRCTN22488978. Registered 06/04/2000.

Diagnosis of Liver Fibrosis With Wisteria floribunda Agglutinin-Positive Mac-2 Binding Protein (WFA-M2BP) Among Chronic Hepatitis B Patients

Background

Wisteria floribunda agglutinin-positive Mac-2 binding protein (WFA-M2BP) is a protein with altered glycosylation that reacts with lectin, and was recently identified as a useful non-invasive biomarker for the diagnosis of liver fibrosis in patients with hepatitis C virus infection.This study aimed to evaluate the diagnostic efficacy of WFA-M2BP for liver fibrosis in the context of hepatitis B virus (HBV).

Methods

We enrolled 151 patients infected with HBV. Liver biopsy and elastography (Fibroscan) were performed during the initial visit. Fibrosis was graded according to the Knodell histologic activity index (F0–3). WFA-M2BP levels were determined with an automated immunoassay analyzer (M2BPGi, HISCL-5000, Sysmex, Japan). The diagnostic efficacy of WFA-M2BP was compared with those of various conventional or composite biomarkers, including enhanced liver fibrosis (ELF) score, Fibroscan, aspartate transaminase (AST)-to-platelet ratio index (APRI), and FIB-4, based on the area under the ROC curve (AUC) value.

Results

The majority of patients were at fibrosis stages F1 and F2. The F2 and F3 AUC values for WFA-M2BP were similar to those for FIB-4, APRI, ELF, and Fibroscan, although the latter showed the best diagnostic efficacy. The diagnostic accuracy of all tested biomarkers for F2 and F3 was 60–70%. In multivariate analysis, WFA-M2BP, ELF, and platelet count significantly predicted stage ≥F2, whereas only platelet count significantly predicted F3.

Conclusions

WFA-M2BP can support a diagnosis of liver fibrosis with similar diagnostic efficacy to other biomarkers, and predicted liver fibrosis stage ≥2 among patients with chronic hepatitis B.

Utility of the ELF Test for Detecting Steatohepatitis in Morbid Obese Patients with Suspicion of Nonalcoholic Fatty Liver Disease

BACKGROUND

Morbid obese patients have a high rate of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). NASH is related to the progression and poor evolution of chronic hepatopathy in NAFLD, so that its detection makes it possible to identify the subjects who are most at risk in order to prioritize treatment. The ELF test (Enhanced Liver Fibrosis test; Siemens Diagnostics, NY, USA) has been assessed for its capacity to detect fibrosis in patients with NAFLD, but its capacity for diagnosing NASH has not been checked.

AIMS

Our objective is to determine the utility of the ELF test for detecting NASH in morbid obese patients with suspected NAFLD.

METHODS

ELF values were determined in a cohort of obese patients who underwent bariatric surgery with suspected NAFLD. Liver biopsy was used as the reference standard.

RESULTS

The values of ELF were significantly higher in patients with NASH (p = 0.002) and in those who presented with metabolic syndrome (p = 0.047). An ELF cut-off point of 8.72 allows the detection of patients with NASH with a sensitivity of 71.4% and a specificity of 74.1% (AUC = 0.742, p = 0.002).

CONCLUSIONS

The ELF test is efficient for the identification of obese patients with NAFLD and early signs of steatohepatitis and fibrosis.

Latent Class Analysis of Noninvasive Methods and Liver Biopsy in Chronic Hepatitis C: An Approach without a Gold Standard

Aims

To evaluate the applicability of the Latent Class Analysis (LCA) and accuracy of transient elastography (TE), aspartate-to-platelet-ratio-index (APRI), enhanced liver fibrosis (ELF), and liver biopsy (LB) for liver fibrosis assessment in a model without a gold standard.

Methods

Significant fibrosis was defined as TE ≥ 7.1 kPa, APRI ≥ 1.5, ELF ≥ 9.37, or LB METAVIR F ≥ 2. Cirrhosis was defined as TE ≥ 12.5 kPa, APRI ≥ 2.0, ELF ≥ 10.31, or LB as METAVIR F = 4.

Results

117 patients with chronic hepatitis C were included. In the LCA, for significant fibrosis the sensitivities and specificities (95% CI) were 0.92 (0.86–0.98) and 0.79 (0.72–0.86) for TE; 0.47 (0.40–0.54) and 0.99 (0.95–1.00) for APRI; 0.81 (0.74–0.88) and 0.78 (0.71–0.85) for ELF; and 0.86 (0.68–1.00) and 0.91 (0.79–1.00) for LB. For cirrhosis, the sensitivities and specificities were 0.92 (0.76–1.00) and 0.94 (0.91–0.97) for TE; 0.57 (0.37–0.77) and 0.97 (0.93–1.00) for APRI; 0.94 (0.84–1.00) and 0.88 (0.82–0.94) for ELF; and 0.30 (0.12–0.48) and 1.00 for LB.

Conclusion

LCA was useful to evaluate accuracy of methods for liver fibrosis staging. Sensitivities and specificities of noninvasive methods were increased in LCA compared to the use of LB as the gold standard.

Wisteria floribunda agglutinin-positive human Mac-2 binding protein predicts the risk of HBV-related liver cancer development

BACKGROUND & AIMS

Wisteria floribunda agglutinin-positive human Mac-2 binding protein (WFA+ -M2BP) can be used to assess the degree of liver fibrosis, but few studies have investigated its prognostic utility. We evaluated whether serum WFA+ -M2BP can predict the development of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients.

METHODS

A total of 1323 CHB patients with WFA+ -M2BP test results between 2009 and 2011 were included in this retrospective analysis.

RESULTS

The mean age of patients (793 men) was 51.0 years. During the follow-up period (median 60.3 months), 52 (3.9%) patients developed HCC. Age, the proportion of male gender, the presence of diabetes and cirrhosis, and levels of aspartate aminotransferase, alpha-foetoprotein, and WFA+ -M2BP were significantly greater in patients with HCC than in those without HCC, whereas serum albumin levels and platelet counts were significantly lower in patients with HCC than in those without HCC (all P<.05). In multivariate analysis, WFA+ -M2BP level was an independent predictor of HCC development (adjusted hazard ratio 1.143, 95% CI: 1.139-1.829), along with male gender and diabetes (all P<.05). In patients without cirrhosis (n=1087), WFA+ -M2BP levels ≥1.8 were associated with a higher risk of HCC development (P<.001 by log-rank test), whereas WFA+ -M2BP levels ≥1.8 tended to be associated with a higher risk of HCC development in patients with cirrhosis (n=236) (P=.073 by log-rank test).

CONCLUSIONS

WFA+ -M2BP level can independently predict HCC development. Further studies should investigate whether WFA+ -M2BP level could be incorporated into surveillance strategies for CHB patients.

Diagnosing schistosomiasis-induced liver morbidity: implications for global control

BACKGROUND

Subclinical morbidity due to schistosomiasis was evaluated in 565 patients, and the enhanced liver fibrosis (ELF) test was assessed for the first time as a potential screening tool for disease.

METHODS

The prevalence and intensity of infection were determined by Kato-Katz thick smear stool examination at baseline and 2 years after curative treatment. The degree of hepatic fibrosis was assessed by ultrasound. Non-invasive serum biomarkers of hepatic fibrosis were also evaluated.

RESULTS

The baseline human prevalence and infection intensity were found to be moderately high at 34% and 123 eggs per gram, respectively. However, hepatic parenchymal fibrosis occurred in 50% of subjects, with grade II fibrosis in 19% and grade III in 6%. The ELF score and higher serum levels of tissue inhibitor of metalloproteinase 1 (TIMP-1) and hyaluronic acid (HA) correlated with the grade of liver fibrosis.

CONCLUSIONS

The findings of this study demonstrated that praziquantel treatment had a short-term impact on both the prevalence and intensity of infection, but less of an impact on established morbidity. Higher TIMP-1 and HA serum levels, and an ELF cut-off score of 8 were found to be correlated with the grade of liver fibrosis; these values may, therefore, assist physicians in identifying individuals at greater risk of disease.

Enhanced liver fibrosis panel as a predictor of liver fibrosis in chronic hepatitis C patients

BACKGROUND

Evaluation of fibrosis is crucial in the assessment of chronic hepatitis C (CHC). The enhanced liver fibrosis (ELF) is a serological panel including hyaluronic acid (HA), tissue inhibitor of matrix metalloproteinases-1 (TIMP-1), and amino-terminal propeptide of type III procollagen (PIIINP) that has shown good results in predicting liver fibrosis in distinct scenarios of chronic liver diseases.

AIMS

We aimed to assess the performance of ELF on the detection of fibrosis and cirrhosis in a CHC patient cohort and to compare the results of ELF and transient elastography (TE-Fibroscan) using liver biopsy as reference.

PATIENTS AND METHODS

One hundred twenty patients were prospectively evaluated by TE and ELF using an ADVIA Centaur automated system. The ELF score was calculated using the manufacturer's algorithm. Biopsies were classified according to the METAVIR score. Receiver operator characteristic curve analyses were performed to evaluate the accuracy of ELF and TE.

RESULTS

The area under the receiver operator characteristic curve (AUROC) of ELF for the diagnosis of significant fibrosis was 0.81 [95% confidence interval (CI), 0.73-0.87], for advanced fibrosis was 0.82 (95% CI, 0.74-0.88), and for cirrhosis was 0.78 (95% CI, 0.70-0.85). Using the proposed cutoffs, ELF overestimated fibrosis in 66% (81/120) of cases and underestimated in 3% (3/120). We found no statistically significant difference when comparing the AUROC of ELF and TE for diagnosing fibrosis or cirrhosis.

CONCLUSIONS

ELF panel is a good noninvasive fibrosis marker and showed similar results to TE in CHC patients. However, new cutoff points need to be established to improve its performance on patients with CHC.

Risk assessment of clinical outcomes in Asian patients with chronic hepatitis B using enhanced liver fibrosis test

Serum fibrosis markers, such as the enhanced liver fibrosis (ELF) test, have been suggested as alternatives for liver biopsy (LB) in assessing liver fibrosis. We investigated the efficacy of the ELF test in predicting development of liver-related events (LREs) in patients with chronic hepatitis B (CHB). A total of 170 patients (103 men; 60.6%) with CHB who underwent LB and serological tests for determining ELFs were enrolled. All patients were followed up to monitor LRE development, defined as hepatic decompensation, hepatocellular carcinoma, and/or liver-related death. The mean age was 45.3 years. During the follow-up period (median, 41 months), 39 (22.9%) patients experienced LREs. In patients with LREs, age, proportion of male gender, ELF test results, age-spleen-platelet ratio (ASPRI), liver stiffness (LS) value, and proportion of histological cirrhosis were significantly higher than those in patients without LREs (all P < 0.05). Areas under the receiver operating characteristic curves to predict LRE development were 0.808 for the ELF test, 0.732 for LS value, 0.713 for histological fibrosis stages using Batts and Ludwig's scoring system, and 0.687 for ASPRI. On multivariate analysis, along with age, the ELF test was an independent predictor of LRE development (adjusted hazard ratio [HR], 1.438; P < 0.001). When we applied a three-tier stratification of our study population using cut-off ELF values of 8.10 and 10.40, patients with low (P = 0.002; adjusted HR: 0.045; 95% confidence interval [CI]: 0.006-0.330) and intermediate (P < 0.001; adjusted HR: 0.239; 95% CI: 0.122-0.469) ELF range were found less likely to develop LREs, compared to those with high ELF range.

CONCLUSION

ELF is useful in a noninvasive prediction of LRE development. Transient elastography showed a statistically similar prognostic performance for LREs as the ELF, but other noninvasive tests were inferior.

Non-invasive hepatic biomarkers (ELF and CK18) in people with type 2 diabetes: the Edinburgh type 2 diabetes study

BACKGROUND & AIMS

Type 2 diabetes is an established risk factor for the presence and progression of fatty liver. Little is known about the distributions and correlates of hepatic non-invasive biomarkers in community-based populations with diabetes, unselected for liver disease. We aimed to identify the distribution of, and metabolic risk factors associated with serum cytokeratin-18 (CK18) and the Enhanced Liver Fibrosis score (ELF), in a large, representative cohort of people with type 2 diabetes (the Edinburgh Type 2 Diabetes Study, ET2DS).

METHODS

Nine hundred and thirty-nine ET2DS participants, aged 60-74 years underwent physical examination including ultrasound for assessment of liver fat. Representative subgroups were assessed for markers of chronic liver disease (CK18 and ELF).

RESULTS

CK18 values ranged from 29-993 U/L (median 102, IQR 76-137 U/L) and ELF scores ranged from 6.9-11.6 (mean 8.9, SD 0.8). Statistically significant associations were found between both biomarkers and a number of metabolic risk factors. Neither CK18 nor ELF was consistently or strongly associated with established hepatic risk factors (alcohol excess, hepatotoxic medication use and positive immunology titres).

CONCLUSIONS

We identified the distribution of CK18 and ELF in a large cohort of older people with type 2 diabetes and showed that these markers are associated with an adverse metabolic risk factor profile, although much of the variation in biomarkers remained unexplained. Prospective studies are required to determine the extent to which CK18 and/or ELF predict the development of symptomatic liver disease and to identify additional risk factors which may influence the development of advanced liver disease in people with type 2 diabetes.

The performance of enhanced liver fibrosis (ELF) test for the staging of liver fibrosis: a meta-analysis

BACKGROUND

The enhanced liver fibrosis test (ELF) has been shown to accurately predict significant liver fibrosis in several liver diseases.

AIMS

To perform a meta-analysis to assess the performance of the ELF test for the assessment of liver fibrosis.

STUDY

Electronic and manual searches were performed to identify studies of the ELF test. After methodological quality assessment and data extraction, pooled estimates of the sensitivity, specificity, area under the receiver operating characteristic curve (AUROC), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and summary receiver operating characteristics (sROC) were assessed systematically. The extent of heterogeneity and reasons for it were assessed.

RESULTS

Nine studies were identified for analysis. The pooled sensitivity, specificity, positive LR, negative LR, and DOR values of ELF test, for assessment of significant liver fibrosis, were 83% (95% CI=0.80-0.86), 73% (95% CI=0.69-0.77), 4.00 (95% CI=2.50-6.39), 0.24 (95% CI=0.17-0.34), and 16.10 (95% CI=8.27-31.34), respectively; and, for evaluation of severe liver fibrosis, were 78% (95% CI=0.74-0.81), 76% (95% CI=0.73-0.78), 4.39 (95% CI=2.76-6.97), 0.27 (95% CI=0.16-0.46), and 16.01 (95% CI: 7.15-35.82), respectively; and, for estimation of cirrhosis, were 80% (95% CI=0.75-0.85), 71% (95% CI=0.68-0.74), 3.13 (95% CI=2.01-4.87), 0.29 (95% CI=0.19-0.44), and 14.09 (95% CI: 5.43-36.59), respectively.

CONCLUSIONS

The ELF test shows good performance and considerable diagnostic value for the prediction of histological fibrosis stage.