Françoise Imbert-Bismut

Biochemical markers of liver fibrosis in patients with hepatitis C virus infection: a prospective study

BACKGROUND Liver biopsy is thought mandatory for management of patients with hepatitis C virus (HCV) infection, especially for staging fibrosis. We aimed, in our prospective study, to assess the predictive value of a combination of basic serum biochemical markers for diagnosis of clinically significant fibrosis (including early stages). METHODS We assessed liver-biopsy patients with detectable HCV by PCR, for eligibility, and took a blood sample on the day of the procedure. The analysis was done in a first-year period for 205 patients and then tested in a second period on 134 patients. We devised a fibrosis index that included the most informative markers (combined with age and sex) for the first-year group. 11 serum markers were assessed as well as fibrosis stage: F0=no fibrosis and F1=portal fibrosis; and for clinically significant fibrosis, F2=few septa, F3=many septa, and F4=cirrhosis. Statistical analysis was by logistic regression, neural connection, and receiver-operating characteristic (ROC) curves. FINDINGS First-year and second-year patient-group characteristics and biochemical markers did not differ. The overall frequency of clinically significant fibrosis was 40% (138 patients). The most informative markers were: alpha2 macroglobulin, alpha2 globulin (or haptoglobin), gamma globulin, apolipoprotein A1, gamma glutamyltranspeptidase, and total bilirubin. The areas (SD) under the ROC curves for the first-year (0.836 [0.430]) and second-year groups (0.870 [0.340]) did not differ (p=0.44). With the best index, a high negative predictive value (100% certainty of absence of F2, F3, or F4) was obtained for scores ranging from zero to 0.10 (12% [41] of all patients), and high positive predictive value (>90% certainty of presence of F2, F3, or F4) for scores ranging from 0.60 to 1.00 (34% [115] of all patients). INTERPRETATION A combination of basic serum markers could be used to substantially reduce the number of liver biopsies done in patients with chronic HCV infection.

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

BackgroundLiver 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.Methods170 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.ResultsIn 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%).ConclusionIn patients with NAFLD, FibroTest, a simple and non-invasive quantitative estimate of liver fibrosis reliably predicts advanced fibrosis.

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

SummaryBackgroundRecent 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.ResultsA 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).ConclusionsBased 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.

Prediction of liver histological lesions with biochemical markers in patients with chronic hepatitis B

BACKGROUND AIMS Liver biopsy is the gold standard for assessing hepatitis B virus (HBV)-related histology. The aim was to determine the diagnostic utility of noninvasive serum markers in patients with chronic hepatitis B. METHODS The aminotransferases and indices including alpha(2)-macroglobulin, apolipoprotein A1, haptoglobin, gamma-glutamyl-transpeptidase (GGT), and total bilirubin (Fibrotest), and ALT (Actitest) were compared with liver histology. The primary outcomes were A2-A3 activity and F2-F4 fibrosis (METAVIR). RESULTS Two hundred and nine patients were included. Forty-one patients (20%) had A2-A3 activity and 61 (29%) had F2-F4 fibrosis. AST and GGT (P<0.001) were independently associated with A2-A3 activity. AST, ALT, and Actitest accurately predicted activity ((areas under receiver operating characteristic (ROC) curves (AUROC), 0.81-0.82+/-0.04)); an AST or ALT< or =30IU/l excluded significant activity with 96% certainty. Fibrotest accurately predicted F2-F4 fibrosis (AUROC, 0.78+/-0.04). Fibrotest scores (range, 0-1.0) < or =0.20 and >0.80 had negative and positive predictive values of 92%, respectively. Restricting biopsy to patients with intermediate scores (>0.20 and < or =0.80) may prevent liver biopsies in 46% of patients while maintaining 92% accuracy. CONCLUSIONS The aminotransferases and an index including five biochemical markers are accurate noninvasive markers of HBV-related activity and fibrosis, respectively.

Meta-analyses of FibroTest diagnostic value in chronic liver disease

BackgroundFibroTest (FT) is a biomarker of liver fibrosis initially validated in patients with chronic hepatitis C (CHC).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.MethodsThe 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.ResultsA 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).ConclusionFibroTest 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.

Intra-laboratory analytical variability of biochemical markers of fibrosis (Fibrotest) and activity (Actitest) and reference ranges in healthy blood donors.

Abstract Combinations of tests comprising α2-macroglobulin, haptoglobin, apolipoprotein A1, γ-glutamyltransferase, total bilirubin (Fibrotest) and alanine aminotransferase (Actitest) are being developed as alternatives to liver biopsy in patients with chronic hepatitis C. The aim of this study was to assess in the same laboratory the impact of parameter assay variations on Fibrotest and Actitest results and intra-patient reproducibility of the two tests. The stability of the samples for each test was studied after storage at −80° and −20°. Within-run, between-run and total imprecision for each parameter assay, and for Fibrotest and Actitest results, were determined. Transferability of assay results between different analyzers was studied. Intrapatient reproducibility was assessed in 55 hospitalized patients. Fibrotest and Actitest reference ranges were determined in 300 blood donors (reference group). The stability of the parameters was affected by serum storage at −20° only. The impact of parameter analytical variability on Fibrotest and Actitest results was less than 10% and intra-patient reproducibility was acceptable (p>0.05). The transferability between different analyzers of results of assays performed under the same standardized and calibration conditions was excellent. Fibrotest and Actitest reference ranges in blood donors were (mean±SE) 0.075±0.004 and 0.068±0.004, respectively. The low intra-laboratory and intra-patient variability in Fibrotest and Actitest results confirm Fibrotest and Actitest reliability.

Longitudinal assessment of histology surrogate markers (FibroTest-ActiTest) during lamivudine therapy in patients with chronic hepatitis B infection

OBJECTIVES:The noninvasive serum markers, FibroTest–ActiTest (FT–AT), are an alternative to liver biopsy in patients with chronic hepatitis C and B. The aim was to use these markers in a prospective study of patients treated with lamivudine in order to assess the impact of treatment, as well as the factors associated with fibrosis progression.METHODS:Two hundred and ninety-eight patients were included in a prospective longitudinal study in 50 hospitals across France. FT–AT were measured at baseline, and then after 6, 12, and 24 months of lamivudine 100-mg treatment. Epidemiological, clinical, and virologic characteristics were analyzed by univariate and multivariate analysis.RESULTS:Two hundred and eighty-three patients were included for analysis. The accuracy of FT–AT versus biopsy was validated with the area under the ROC curve, 0.77 (SE = 0.03) for bridging fibrosis and 0.75 (SE = 0.06) for severe activity (A3). At baseline, bridging fibrosis (METAVIR stages F2–F3–F4) was highly associated (p < 0.001) in multivariate analysis with male gender and age and marginally associated with anti-HBe presence (p= 0.05) and non-Asian ethnic origin (p= 0.046). Lamivudine treatment had a very significant impact overall. FT decreased significantly from 0.51 at baseline to 0.37 at 24 months (p < 0.001), and 85% of patients had improvement at 24 months. AT also decreased significantly from 0.56 to 0.13 (p < 0.0001), and 91% of patients had improvement at 24 months. A three-phase kinetics was observed for both fibrosis and activity; there was a marked improvement during the first 6 months, followed by a plateau between 6 and 12 months, and another improvement between 12 and 24 months. The occurrence of a YMDD variant does not entirely explain these three-phase variations. The first phase impact on fibrosis rates was higher in Asian patients (p= 0.01) and in patients younger than 40 yr (p < 0.001).CONCLUSIONS:In patients with chronic hepatitis B, a 24-month course of lamivudine treatment leads to a significant decrease in necroinflammatory grades and fibrosis stages as assessed by noninvasive markers, with the occurrence of a three-phase kinetics. FT–AT should be useful in the noninvasive follow-up of lamivudine treatment.

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

BackgroundBiochemical 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, α2-macroglobulin, haptoglobin, apolipoprotein A1, and total bilirubin) and to identify factors associated with this variability.ResultsSerum 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.ConclusionsThe 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.

The predictive value of fibrotest vs. APRI for the diagnosis of fibrosis in chronic hepatitis C

Wai et al.1 developed indexes that identified significant fibrosis in patients with chronic hepatitis C. These indexes, including aspartate aminotransferase (AST) and platelets, had good discriminative power, as shown by areas under the receiver operating characteristic curve (AUROC) of 0.82 for formula 1 predicting fibrosis, 0.92 for formula 2 predicting cirrhosis, 0.83 for ASTPlatelets Ratio Index (APRI) for fibrosis, and 0.90 for cirrhosis. We also validated a fibrosis index (Fibrotest; Biopredictive, Houilles, France, US Patent Application Serial No. 09/687,459) with high predictive values.2– 4 We sought to compare these indices by using data collected retrospectively in 323 patients from our original population with complete biochemical data.2 The prevalence of significant fibrosis (F2–F4) was 41%, and cirrhosis (F4) was 13%. The mean value (SE) for AST expressed in ULN was 1.71 (0.10) and platelets count 192 (3) 109/L. AUROCs for significant fibrosis were 0.75 (0.03) for formula 1 and 0.74 (0.03) for APRI versus 0.83 (0.02) for Fibrotest (P 0.03 vs. formula 1 and P 0.02 vs. APRI),5 suggesting that the latter has greater discriminative power. The AUROCs for cirrhosis were 0.82 (0.04) for formula 2 and 0.80 (0.04) for APRI versus 0.92 (0.03) for Fibrotest (P 0.04 vs. formula 2 and P 0.02 vs. APRI), suggesting that the latter has greater discriminative power. There was a continuous, almost linear, relationship between Fibrotest and fibrosis stage, with significant differences between stages that were not observed for the Wai1 indexes (Fig. 1). In addition to superior diagnostic power, Fibrotest has several other advantages. First, Fibrotest is not transaminase-dependent. AST has poor sensitivity for fibrosis detection. When we apply the sensitive cut-off recommended (1.00),1 we observe a 27% falsenegative rate for cirrhosis: 11 out of 41 patients with cirrhosis had an APRI below 1.00. Among these 11 patients, 6 had normal AST values. We observed 25 fibrotic patients out of 131 (19% falsenegative rate) who had APRI of 0.50 or below, the cut-off recommended for excluding significant fibrosis. Among these 25 patients, 22 had normal AST. The so-called standardization of transaminases using the upper normal limit given by laboratories is hazardous.6 To explain the differences in sensitivities observed in our population versus the Wai population, we wonder if, in their center, they were performing biopsies routinely in patients with normal transaminases, as we did in our center. This type of selection could have overestimated the sensitivity of AST. Second, we did not include platelet count in Fibrotest to develop an index easily automated using minimal equipment. The components of Fibrotest can be measured using a single autoanalyzer with minimal variability.6 Third, Fibrotest has been validated in patients with human immunodeficiency virus/HCV-coinfection,4 who often have thrombocytopenia. Fibrotest is responsive to changes in fibrosis attributable to interferon-based therapy.3 Finally, a combination of alanine aminotransferase levels and Fibrotest (Actitest) accurately predicts the severity of necroinflammatory activity.2,3 In conclusion, these comparisons suggest that Fibrotest provides a more accurate estimate of HCV-related fibrosis than the Wai indexes.1

Biochemical Markers of Fibrosis in Patients with Chronic Hepatitis C: A Comparison with Prothrombin Time, Platelet Count, and Age–Platelet Index

As an alternative to liver biopsy, an index of five biochemical markers (α2-macroglobulin, apolipoprotein A1, haptoglobin, total bilirubin, γ-glutamyl-transpeptidase) has been shown to predict the severity of hepatitis C-related fibrosis. The objective of this study was to compare this index with other markers frequently used for this purpose (prothrombin time, platelets, age–platelet index). In 323 hepatitis C-infected patients, the discriminative values of these markers for F2–F4 fibrosis (by the METAVIR classification) were compared. By multiple logistic regression analysis, only the five-marker index (P < 0.0001) and prothrombin time (P = 0.02) were independently predictive of F2–F4 fibrosis. For this outcome, the area under the receiver operating characteristic curve was significantly higher for the five-marker index (0.836 ± 0.024) than the age-platelet index (P = 0.002), and the platelet count and prothrombin time (P < 0.001), indicating greater diagnostic value. The addition of the latter markers to the five-marker index proved unhelpful for increasing its accuracy. In conclusion, an index of five biochemical markers accurately predicts significant hepatitis C-related fibrosis and is superior to traditional markers.