Overview of the diagnostic value of biochemical markers of liver fibrosis (FibroTest, HCV FibroSure) and necrosis (ActiTest) in patients with chronic hepatitis C

BACKGROUND: Recent studies strongly suggest that due to the limitations and risks of biopsy, as well as the improvement of the diagnostic accuracy of biochemical markers, liver biopsy should no longer be considered mandatory in patients with chronic hepatitis C. In 2001, FibroTest ActiTest (FT-AT), a panel of biochemical markers, was found to have high diagnostic value for fibrosis (FT range 0.00–1.00) and necroinflammatory histological activity (AT range 0.00–1.00). The aim was to summarize the diagnostic value of these tests from the scientific literature; to respond to frequently asked questions by performing original new analyses (including the range of diagnostic values, a comparison with other markers, the impact of genotype and viral load, and the diagnostic value in intermediate levels of injury); and to develop a system of conversion between the biochemical and biopsy estimates of liver injury. RESULTS: A total of 16 publications were identified. An integrated database was constructed using 1,570 individual data, to which applied analytical recommendations. The control group consisted of 300 prospectively studied blood donors. For the diagnosis of significant fibrosis by the METAVIR scoring system, the areas under the receiver operating characteristics curves (AUROC) ranged from 0.73 to 0.87. For the diagnosis of significant histological activity, the AUROCs ranged from 0.75 to 0.86. At a cut off of 0.31, the FT negative predictive value for excluding significant fibrosis (prevalence 0.31) was 91%. At a cut off of 0.36, the ActiTest negative predictive value for excluding significant necrosis (prevalence 0.41) was 85%. In three studies there was a direct comparison in the same patients of FT versus other biochemical markers, including hyaluronic acid, the Forns index, and the APRI index. All the comparisons favored FT (P < 0.05). There were no differences between the AUROCs of FT-AT according to genotype or viral load. The AUROCs of FT-AT for consecutive stages of fibrosis and grades of necrosis were the same for both moderate and extreme stages and grades. A conversion table was constructed between the continuous FT-AT values (0.00 to 1.00) and the expected semi-quantitative fibrosis stages (F0 to F4) and necrosis grades (A0 to A3). CONCLUSIONS: Based on these results, the use of the biochemical markers of liver fibrosis (FibroTest) and necrosis (ActiTest) can be recommended as an alternative to liver biopsy for the assessment of liver injury in patients with chronic hepatitis C. In clinical practice, liver biopsy should be recommended only as a second line test, i.e., in case of high risk of error of biochemical tests

Intra-individual fasting versus postprandial variation of biochemical markers of liver fibrosis (FibroTest) and activity (ActiTest)

BACKGROUND: Biochemical marker combinations, including α(2)-macroglobulin, haptoglobin, apolipoprotein A1, γ-glutamyl transpeptidase, and total bilirubin (all part of FibroTest) plus alanine aminotransferase (all part of ActiTest), are being developed as alternatives to liver biopsy in patients with chronic hepatitis C and other various chronic liver diseases. Considering this premise, the primary aim of this study was to assess the impact of meal intake on FibroTest and ActiTest results. Such studies are very important for patients, as many clinical errors have been related to the absence of baseline evidence. RESULTS: Intra-individual variation was assessed for the 6 above components and for FibroTest and ActiTest, by measuring time dependent variations before and one hour after a standard meal in 64 subjects. These consisted of 29 healthy volunteers and 35 patients with chronic liver diseases. Meal intake had no significant impact on any of the six components, or on FibroTest or ActiTest, as assessed by repeated measure variance analyses (ANOVA all p > 0.90); the Spearman correlation coefficient ranged from 0.87 (total bilirubin) to 0.995 (γ-glutamyl transpeptidase). The coefficients of variation (CV) between fasting and postprandial measurements fluctuated for the six components from 0.09 (apolipoprotein A1) to 0.14 (α(2)-macroglobulin), and from 0.09 for FibroTest to 0.13 for ActiTest. In contrast, meal intake had a significant impact on triglycerides (ANOVA p = 0.01, CV = 0.65) and glucose (ANOVA p = 0.04, CV = 0.31). As for the prediction of liver injury, the concordance between fasting and postprandial predicted histological stages and grades was almost perfect, both for FibroTest (kappa = 0.91, p < 0.001) and ActiTest (kappa = 0.80, p < 0.001). CONCLUSIONS: The intra-individual variation of biochemical markers was low, and it was shown that measurements of FibroTest, ActiTest and their components are not significantly modified by meal intake. This fact makes the screening of patients at risk of chronic liver diseases more convenient

Concordance in a World without a Gold Standard: A New Non-Invasive Methodology for Improving Accuracy of Fibrosis Markers

BACKGROUND: Assessing liver fibrosis is traditionally performed by biopsy, an imperfect gold standard. Non-invasive techniques, liver stiffness measurements (LSM) and biomarkers [FibroTest(R) (FT)], are widely used in countries where they are available. The aim was to identify factors associated with LSM accuracy using FT as a non-invasive endpoint and vice versa. METHODS: The proof of concept was taken using the manufacturers recommendations for excluding patients at high risk of false negative/positive. The hypothesis was that the concordance between LSM and FT, would be improved by excluding high-risk patients. Thereafter, the impact of potential variability factors was assessed by the same methods. Liver biopsy and independent endpoints were used to validate the results. RESULTS: Applying manufacturers' recommendations in 2,004 patients increased the strength of concordance between LSM and FT (P<0.00001). Among the 1,338 patients satisfying recommendations, the methodology identified a significant LSM operator effect (P = 0.001) and the following variability factors (all P<0.01), related to LSM: male gender, older age, and NAFLD as a cause of liver disease. Biopsy confirmed in 391 patients these results. CONCLUSION: This study has validated the concept of using the strength of concordance between non-invasive estimates of liver fibrosis for the identification of factors associated with variability and precautions of use

The diagnostic value of biomarkers (SteatoTest) for the prediction of liver steatosis

BACKGROUND: Biopsy is the usual gold standard for liver steatosis assessment. The aim of this study was to identify a panel of biomarkers (SteatoTest), with sufficient predictive values, for the non-invasive diagnosis of steatosis in patients with or without chronic liver disease. Biomarkers and panels were assessed in a training group of consecutive patients with chronic hepatitis C and B, alcoholic liver disease, and non-alcoholic fatty liver disease, and were validated in two independent groups including a prospective one. Steatosis was blindly assessed by using a previously validated scoring system. RESULTS: 310 patients were included in the training group; 434 in three validation groups; and 140 in a control group. SteatoTest was constructed using a combination of the 6 components of FibroTest-ActiTest plus body mass index, serum cholesterol, triglycerides, and glucose adjusted for age and gender. SteatoTest area under the ROC curves was 0.79 (SE = 0.03) in the training group; 0.80 (0.04) in validation group 1; 0.86 (0.03) in validation group 2; and 0.72 (0.05) in the validation group 3 – all significantly higher than the standard markers: γ-glutamyl-transpeptidase or alanine aminotransferase. The median SteatoTest value was 0.13 in fasting controls; 0.16 in non-fasting controls; 0.31 in patients without steatosis; 0.39 in grade 1 steatosis (0–5%); 0.58 in grade 2 (6–32%); and 0.74 in grade 3–4 (33–100%). For the diagnosis of grade 2–4 steatosis, the sensitivity of SteatoTest at the 0.30 cut-off was 0.91, 0.98, 1.00 and 0.85 and the specificity at the 0.70 cut-off was 0.89, 0.83, 0.92, 1.00, for the training and three validation groups, respectively. CONCLUSION: SteatoTest is a simple and non-invasive quantitative estimate of liver steatosis and may reduce the need for liver biopsy, particularly in patients with metabolic risk factor

Prevalence of liver fibrosis and risk factors in a general population using non-invasive biomarkers (FibroTest)

<p>Abstract</p> <p>Background</p> <p>FibroTest and elastography have been validated as biomarkers of liver fibrosis in the most frequent chronic liver diseases and in the fibrosis screening of patients with diabetes. One challenge was to use them for estimating the prevalence of fibrosis, identifying independent risk factors and to propose screening strategies in the general population.</p> <p>Methods</p> <p>We prospectively studied 7,463 consecutive subjects aged 40 years or older. Subjects with presumed advanced fibrosis (FibroTest greater than 0.48) were re-investigated in a tertiary center.</p> <p>Results</p> <p>The sample characteristics were similar to those of the French population. FibroTest was interpretable in 99.6%. The prevalence of presumed fibrosis was 2.8%, (209/7,463), including cirrhosis in 0.3% (25/7,463); 105/209 (50%) subjects with presumed fibrosis accepted re-investigation. Fibrosis was confirmed in 50, still suspected in 27, indeterminate in 25 and not confirmed with false positive FibroTest or false negative elastography in 3 subjects. False negative rate of FibroTest estimated using elastography was 0.4% (3/766). The attributable causes for confirmed fibrosis were both alcoholic and nonalcoholic fatty liver disease (NAFLD) in 66%, NAFLD in 13%, alcohol in 9%, HCV in 6%, and other in 6%. Factors independently associated (all P < 0.003) with confirmed fibrosis were age, male gender, waist circumference, HCV antibody and alcohol consumption estimated using carbohydrate-deficient transferrin, enabling efficient screening-oriented strategies to be compared and proposed.</p> <p>Conclusions</p> <p>Biomarkers have permitted to estimate prevalence of advanced fibrosis around 2.8% in a general population aged 40 years or older, and several risk factors which may be used for the validation of selective or non-selective screening strategies.</p

A prospective assessment of the inter-laboratory variability of biochemical markers of fibrosis (FibroTest) and activity (ActiTest) in patients with chronic liver disease

BACKGROUND: Biochemical markers for liver fibrosis (FibroTest) and necroinflammatory features (ActiTest) are an alternative to liver biopsy in patients with chronic hepatitis C. Our aim was to assess the inter-laboratory variability of these tests, and their 6 components (γ-glutamyl transpeptidase, alanine aminotransferase, α(2)-macroglobulin, haptoglobin, apolipoprotein A1, and total bilirubin) and to identify factors associated with this variability. RESULTS: Serum of 24 patients with chronic hepatitis C or severe alcoholic liver disease were prospectively recorded and analyzed in one reference center and in 8 additional laboratories. When γ-glutamyl transpeptidase and alanine aminotransferase were expressed in international units, there was no significant difference between laboratories in the results of FibroTest or ActiTest; kappa statistics were greater than 0.50 with only 0.8% of cases (3/384) with a discordance of more than one stage. The main factor significantly associated with variability was the expression of γ-glutamyl transpeptidase and alanine aminotransferase, as multiples of upper limit of reference values. The use of standardized method with pyridoxal phosphate reduced the variability of alanine aminotransferase expression, and standardized original Szasz method reduced the variability of γ-glutamyl transpeptidase expression. CONCLUSIONS: The variability of FibroTest and ActiTest was acceptable without clinical consequences for the prediction of the stage of liver fibrosis and grade of activity. Standardized methods and assay calibration should be used and expression of alanine aminotransferase and γ-glutamyl transpeptidase in multiples of the upper limit of reference values should not be employed

Meta-analyses of FibroTest diagnostic value in chronic liver disease

<p>Abstract</p> <p>Background</p> <p>FibroTest (FT) is a biomarker of liver fibrosis initially validated in patients with chronic hepatitis C (CHC).</p> <p>The aim was to test two hypotheses, one, that the FT diagnostic value was similar in the three other frequent fibrotic diseases: chronic hepatitis B (CHB), alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD); and the other, that the FT diagnostic value was similar for intermediate and extreme fibrosis stages.</p> <p>Methods</p> <p>The main end points were the FT area under the ROC curves (AUROCs) for the diagnosis of bridging fibrosis (F2F3F4 vs. F0F1), standardized for the spectrum of fibrosis stages, and the comparison of FT AUROCs between adjacent stages. Two meta-analyses were performed: one combining all the published studies (random model), and one of an integrated data base combining individual data. Sensitivity analysis integrated the independency of authors, lenght of biopsy, prospective design, respect of procedures, comorbidities, and duration between biopsy and serum sampling.</p> <p>Results</p> <p>A total of 30 studies were included which pooled 6,378 subjects with both FT and biopsy (3,501 HCV, 1,457 HBV, 267 NAFLD, 429 ALD, and 724 mixed). Individual data were analyzed in 3,282 patients. The mean standardized AUROC was 0.84 (95% CI, 0.83–0.86), without differences between causes of liver disease: HCV 0.85 (0.82–0.87), HBV 0.80 (0.77–0.84), NAFLD 0.84 (0.76–0.92), ALD 0.86 (0.80–0.92), mixed 0.85 (0.80–0.93). The AUROC for the diagnosis of the intermediate adjacent stages F2 vs. F1 (0.66; 0.63–0.68, n = 2,055) did not differ from that of the extreme stages F3 vs. F4 (0.69; 0.65–0.72, n = 817) or F1 vs. F0 (0.62; 0.59–0.65, n = 1788).</p> <p>Conclusion</p> <p>FibroTest is an effective alternative to biopsy in patients with chronic hepatitis C and B, ALD and NAFLD. The FT diagnostic value is similar for the diagnosis of intermediate and extreme fibrosis stages.</p

Applicability and precautions of use of liver injury biomarker FibroTest. A reappraisal at 7 years of age

<p>Abstract</p> <p>Background</p> <p>FibroTest (FT) is a validated biomarker of fibrosis. To assess the applicability rate and to reduce the risk of false positives/negatives (RFPN), security algorithms were developed. The aims were to estimate the prevalence of RFPN and of proven failures, and to identify factors associated with their occurrences.</p> <p>Methods</p> <p>Four populations were studied: 954 blood donors (P1), 7,494 healthy volunteers (P2), 345,695 consecutive worldwide sera (P3), including 24,872 sera analyzed in a tertiary care centre (GHPS) (P4). Analytical procedures of laboratories with RFPN > 5% and charts of P4 patients in with RFPN were reviewed.</p> <p>Results</p> <p>The prevalence of RFPN was 0.52% (5/954; 95%CI 0.17-1.22) in P1, 0.51% (38/7494; 0.36-0.70) in P2, and 0.97% (3349/345695; 0.94-1.00) in P3. Three a priori high-risk populations were confirmed: 1.97% in P4, 1.77% in HIV centre and 2.61% in Sub-Saharan origin subjects. RFPN was mostly associated with low haptoglobin (0.46%), and high apolipoproteinA1 (0.21%). A traceability study of a P3 laboratory with RFPFN > 5% permitted to correct analytical procedures.</p> <p>Conclusion</p> <p>The mean applicability rate of Fibrotest was 99.03%. Independent factors associated with the high risk of false positives/negatives were HIV center, subSaharan origin, and a tertiary care reference centre, although the applicability rate remained above 97%.</p

An Accurate Definition of the Status of Inactive Hepatitis B Virus Carrier by a Combination of Biomarkers (FibroTest-ActiTest) and Viral Load

BACKGROUND: The combination of transaminases (ALT), biopsy, HBeAg and viral load have classically defined the inactive status of carriers of chronic hepatitis B. The use of FibroTest (FT) and ActiTest (AT), biomarkers of fibrosis and necroinflammatory activity, has been previously validated as alternatives to biopsy. We compared the 4-year prognostic value of combining FT-AT and viral load for a better definition of the inactive carrier status. METHODS AND FINDINGS: 1,300 consecutive CHB patients who had been prospectively followed since 2001 were pre-included. The main endpoint was the absence of liver-related complications, transplantation or death. We used the manufacturers' definitions of normal FT (< = 0.27), normal AT (< = 0.29) and 3 standard classes for viral load. The adjustment factors were age, sex, HBeAg, ethnic origin, alcohol consumption, HIV-Delta-HCV co-infections and treatment. RESULTS: 1,074 patients with baseline FT-AT and viral load were included: 41 years old, 47% African, 27% Asian, 26% Caucasian. At 4 years follow-up, 50 complications occurred (survival without complications 93.4%), 36 deaths occurred (survival 95.0%), including 27 related to HBV (survival 96.1%). The prognostic value of FT was higher than those of viral load or ALT when compared using area under the ROC curves [0.89 (95%CI 0.84-0.93) vs 0.64 (0.55-0.71) vs 0.53 (0.46-0.60) all P<0.001], survival curves and multivariate Cox model [regression coefficient 5.2 (3.5-6.9; P<0.001) vs 0.53 (0.15-0.92; P = 0.007) vs -0.001 (-0.003-0.000;P = 0.052)] respectively. A new definition of inactive carriers was proposed with an algorithm combining "zero" scores for FT-AT (F0 and A0) and viral load classes. This new algorithm provides a 100% negative predictive value for the prediction of liver related complications or death. Among the 275 patients with the classic definition of inactive carrier, 62 (23%) had fibrosis presumed with FT, and 3 died or had complications at 4 year. CONCLUSION: In patients with chronic hepatitis B, a combination of FibroTest-ActiTest and viral load testing accurately defined the prognosis and the inactive carrier status

Diagnostic value of biochemical markers (FibroTest-FibroSURE) for the prediction of liver fibrosis in patients with non-alcoholic fatty liver disease

BACKGROUND: Liver biopsy is considered as the gold standard for assessing non-alcoholic fatty liver disease (NAFLD) histologic lesions. The aim of this study was to determine the diagnostic utility of non-invasive markers of fibrosis, validated in chronic viral hepatitis and alcoholic liver disease (FibroTest, FT), in patients with NAFLD. METHODS: 170 patients with suspected NAFLD were prospectively included in a reference center (Group 1), 97 in a multicenter study (Group 2) and 954 blood donors as controls. Fibrosis was assessed on a 5 stage histological scale validated by Kleiner et al from F0 = none, F1 = perisinusoidal or periportal, F2 = perisinusoidal and portal/periportal, F3 = bridging and F4 = cirrhosis. Histology and the biochemical measurements were blinded to any other characteristics. The area under the ROC curves (AUROC), sensitivity (Se), specificity (Sp), positive and negative predictive values (PPV, NPV) were assessed. RESULTS: In both groups FT has elevated and not different AUROCs for the diagnosis of advanced fibrosis (F2F3F4): 0.86 (95%CI 0.77–0.91) versus 0.75 (95%CI 0.61–0.83; P = 0.10), and for F3F4: 0.92 (95%CI 0.83–0.96) versus 0.81 (95%CI 0.64–0.91; P = 0.12) in Group1 and Group 2 respectively. When the 2 groups were pooled together a FT cutoff of 0.30 had a 90% NPV for advanced fibrosis (Se 77%); a FT cutoff of 0.70 had a 73% PPV for advanced fibrosis (Sp 98%). CONCLUSION: In patients with NAFLD, FibroTest, a simple and non-invasive quantitative estimate of liver fibrosis reliably predicts advanced fibrosis