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

BackgroundBiopsy 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.Results310 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.ConclusionSteatoTest 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.

Diagnostic and prognostic values of noninvasive biomarkers of fibrosis in patients with alcoholic liver disease

FibroTest has been validated as a biomarker of fibrosis in patients with chronic viral hepatitis, with a similar prognostic value as biopsy. The aim of the study was to compare the diagnostic and prognostic values of FibroTest versus the recently patented biomarkers, FibrometerA, and Hepascore. A total of 218 consecutive patients with ALD and available liver biopsy examination were included. Biomarkers were compared using univariate area under the ROC curves (AUROC) and multivariate analysis (logistic regression and Cox). The median follow‐up was 8.2 years. Eighty‐five patients died, including 42 deaths related to liver complications. The diagnostic values of FibrometerA and Hepascore did not differ from that of FibroTest for advanced fibrosis (all AUROC = 0.83 ± 0.03) and cirrhosis (FibroTest and FibrometerA = 0.94 ± 0.02, Hepascore = 0.92 ± 0.02), and were significantly greater than those of nonpatented biomarkers (APRI, Forns, FIB4; P < 0.01). In multivariate analysis the most significant was FibroTest (P = 0.001), without independent diagnostic value for FibrometerA (P = 0.19), and Hepascore (P = 0.40). The prognostic values of FibroTest (AUROC for survival or non liver disease‐related death = 0.79 ± 0.04), FibrometerA (0.80 ± 0.04), Hepascore (0.78 ± 0.04), did not differ from that of biopsy fibrosis staging (0.77 ± 0.04). In multivariate analysis the most significant were FibroTest (P = 0.004) and biopsy (P = 0.03), without independent prognostic values for FibrometerA (P = 0.41) and Hepascore (P = 0.28). In patients with alcoholic liver disease, FibrometerA and Hepascore did not improve the diagnostic and prognostic values of FibroTest. (HEPATOLOGY 2009;49:97‐105.)

Liver fibrosis evaluation using real-time shear wave elastography: Applicability and diagnostic performance using methods without a gold standard

BACKGROUND & AIMS Real-time shear wave elastography (SWE) is a new two-dimensional transient elastography which had no assessment of factors associated with reliability, and had limited comparisons with other validated fibrosis biomarkers. The aim was to assess the applicability and performances of SWE for the diagnosis of fibrosis as compared with FibroTest (FT) and liver stiffness measurement (LSM) by transient elastography using two probes (TE-M and TE-XL). METHODS Without a gold standard, the strength of concordance, discordance analysis and latent class analysis (LCM) were applied. RESULTS 422 patients were included. The applicability of SWE (90.0%) was significantly lower than that of FT (97.9%; p <0.0001) and did not differ from those of TE-M (90.5%) and TE-XL (90.3%); it was higher though for SWE (86%) in 22 patients with ascites vs. 55% using TE-M (p=0.04). For the diagnosis of all fibrosis stages as presumed by FT, the performance of SWE was highly significant (Obuchowski measure 0.807 ± 0.013 [m ± se]), but lower than those of TE-M (0.852; p=0.0007) and TE-XL (0.834; p=0.046). SWE had a low performance for discrimination between F0 and F1. For the diagnosis of cirrhosis using LCM, SWE specificities were all equal to 99%, and SWE sensitivities ranged from 0.47 to 0.64. For the diagnosis of non-cirrhotic stages, the results were heterogeneous. CONCLUSIONS The performance of SWE for the diagnosis of cirrhosis was similar to those of FT and TE. SWE applicability was lower than that of FT, but greater than that of TE in patients with ascites.

Slow regression of liver fibrosis presumed by repeated biomarkers after virological cure in patients with chronic hepatitis C.

BACKGROUND & AIMS Chronic hepatitis C is both a virologic and fibrotic disease and complications can occur in patients with sustained virologic response (SVR) with residual fibrosis. Due to the limitations of repeated biopsies, no studies have assessed the dynamic of fibrosis before and after treatment. Using biopsy as reference, FibroTest™ has been validated as a biomarker of fibrosis progression and regression, with similar prognostic values. The aim was to estimate the impact of SVR on the dynamic of fibrosis presumed by FibroTest™. METHODS In a prospective cohort, the main end point was the 10-year regression rate of fibrosis, defined as a minimum 0.20 decrease in FibroTest™, equivalent to one METAVIR stage. RESULTS A total of 933 patients with both repeated FibroTest™ and transient elastography were included. At 10 years, among the 415 patients with baseline advanced fibrosis, 49% (95% CI 33-64%) of the 108 SVR had a regression, which was greater than in the 219 non-responders [23% (14-33%; p < 0.001 vs. SVR)] and not lower than in the 88 non-treated [45% (10-80%; p = 0.39 vs. SVR)] patients. In all 171 SVR, cirrhosis regressed in 24/43 patients, but 15 new cirrhosis cases occurred out of 128 patients, that is only a net reduction of 5.3% [(24-15) = 9/171); (2.4-9.8%)]. Four cases of primary liver cancer occurred in SVR [4.6% (0-9.8)], and 13 in non-responders [5.6% (1.5-9.8); p = 0.07]. CONCLUSIONS In patients with chronic hepatitis C, and as presumed by FibroTest™, virological cure was associated with slow regression of fibrosis 10years later, a disappointing 5% decrease in cirrhosis cases, and a remaining 5% risk of primary liver cancer.

Liver Biopsy Analysis Has a Low Level of Performance for Diagnosis of Intermediate Stages of Fibrosis

BACKGROUND & AIMS There is controversy about the performance of noninvasive tests such as FibroTest in diagnosing intermediate stages of fibrosis. We investigated whether this controversy results from limitations of biopsy analysis for intermediate-stage fibrosis and inappropriate determination of the standard area under the receiver-operator characteristic curve (AUROC). METHODS To determine whether biopsy has a lower diagnostic performance for fibrosis stage F2 (few septa) vs F1 (fibrosis without septa), compared with its performance for F1 vs F0 or F4 vs F3, we determined the fibrotic areas of large surgical samples collected from 20 consecutive patients with chronic liver disease or normal liver tissue that surrounded tumors. We analyzed digitized images of 27,869 virtual biopsies of increasing length and also analyzed data from 6500 patients with interpretable FibroTest results who also underwent biopsy analysis. RESULTS The overall performance of biopsy analysis (by Obuchowski measure) increased with biopsy length from 0.885 for 5-mm to 0.912 for 30-mm samples (P < .0001). The performance of biopsy was lower for the diagnosis of F2 vs F1 samples (weighted AUROC [wAUROC] = 0.505) than for F1 vs F0 (wAUROC = 0.773; 53% difference; P < .0001) or F4 vs F3 (wAUROC = 0.700; 39% difference; P < .0001), even when 30-mm biopsy samples were used. The performance of FibroTest was also lower for the diagnosis of F2 vs F1 samples (wAUROC = 0.512) than for F1 vs F0 samples (wAUROC = 0.626; 22% difference; P < .0001) or F4 vs F3 (wAUROC = 0.628; 23% difference; P < .0001). However, the FibroTest had smaller percentage differences among wAUROC values than biopsy. CONCLUSIONS Biopsy has a low level of diagnostic performance for fibrosis stages F2 and F1. The recommendation for biopsy analysis, instead of a validated biomarker panel such as FibroTest, for the diagnosis of intermediate stages of fibrosis is therefore misleading.

Biomarkers of liver injury for hepatitis clinical trials: a meta-analysis of longitudinal studies.

BACKGROUND Liver biopsy and virological end points are standard references for assessing the effect of viral hepatitis treatments. We aimed to review evidence-based published data of biomarkers that have been validated as non-invasive alternatives to biopsy as end points for HBV and HCV infection trials. METHODS Studies were included if there were at least two repeated estimates of fibrosis per patient using biomarkers with at least two studies and a control group. Meta-analysis of the percentage of fibrosis progression per year (pFPy) was performed. RESULTS Two biomarkers were included, FibroTest and liver stiffness measurement (LSM; FibroScan. A total of 1,413 patients with chronic hepatitis C (11 populations) and 772 with chronic hepatitis B (6 populations) were analysed. In a comparison of HCV patients with controls, the FibroTest pFPy was -18% (95% confidence interval [CI] -23--14; P<0.001) in treated patients and the LSM pFPy was -15% (95% CI -28--1; P=0.01), both with differences according to virological responses. In HBV patients, there was a significant decrease of the pFPy only in patients with baseline advanced fibrosis (mean difference -5% [95% CI -10--0.1]; P=0.02). In patients with advanced fibrosis, stratified by virological response, there were similar differences between pFPy estimated either using FibroTest or biopsy, both in HCV and HBV infections. Repeated LSM in HBV patients had an early variability related to necroinflammatory activity. CONCLUSIONS In patients with chronic hepatitis C and B, the treatment effect on fibrosis progression rate was similarly estimated using FibroTest or biopsy. The same concordance was observed for FibroScan but with a possible overestimation of the fibrosis regression during the first weeks of treatment.

Impact of adefovir dipivoxil on liver fibrosis and activity assessed with biochemical markers (FibroTest–ActiTest) in patients infected by hepatitis B virus

Summary.  The aim was to assess the utility of FibroTest–ActiTest (FT‐AT) as noninvasive markers of histological changes in patients with chronic hepatitis. Patients with chronic hepatitis B (HBeAg+ and HBeAg−) randomized in two trials of adefovir (ADV) vs placebo, with available paired liver biopsies and FT‐AT at baseline and after 48 weeks of treatment were included. The predictive value of FT‐AT was assessed using the area under the receiver operating characteristics curves (AUROCs) for the diagnosis of bridging fibrosis, cirrhosis and moderate–severe necroinflammatory activity. The impact of treatment with ADV vs placebo was assessed on liver injury according to baseline stage and virological response at 48 weeks. The analysis of 924 estimates for the diagnosis of bridging fibrosis, cirrhosis and moderate or severe necroinflammatory activity yielded FT‐AT AUROCs: 0.76 ± 0.02 (standardized 0.81 ± 0.02), 0.81 ± 0.02 and 0.80 ± 0.01, respectively. Similar impacts of ADV on liver fibrosis and activity were observed both with paired biopsy (fibrosis stage from 1.6 to 1.4, activity grade from 2.5 to 1.3) and paired biomarkers (FT from 0.44 to 0.40, AT from 0.62 to 0.25) (P < 0.0001). FibroTest–ActiTest provides a quantitative estimate of liver fibrosis and necroinflammatory activity in patients with chronic hepatitis B and may be an alternative to reduce the need for liver biopsy.

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

BackgroundFibroTest (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.MethodsFour 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.ResultsThe 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.ConclusionThe 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%.

Methodological aspects of the interpretation of non-invasive biomarkers of liver fibrosis: a 2008 update.

This review summarizes the methodological aspects of the interpretation of non-invasive biomarkers in liver fibrosis. A scoring system has been updated to better compare the quality of fibrosis biomarkers. Several methodological issues are related to the classical methodology using biopsy, as this is considered the gold standard. However, from evidence-based data, it appears that the methodology needs to change to prevent flawed conclusions among key opinion leaders as well as in obsolete guidelines. As waiting for the perfect biomarker for the diagnosis of advanced fibrosis to come along is probably a waste of time, in the meantime, methods can be improved. The main proposals for improving the methodology are, to take into account the spectrum bias, to assess accuracy between adjacent stages, to compare biomarkers in the same patient, to assess the cause of failure among discordant cases and to use specific statistical methods adapted for imperfect gold standards.

Significant Variations in Elastometry Measurements Made Within Short-term in Patients With Chronic Liver Diseases

BACKGROUND & AIMS Transient elastometry is a noninvasive procedure used to measure fibrosis when patients are diagnosed with liver disease; it might be used to monitor changes over time. We investigated whether there are short-term variations in stiffness measurements that are not attributable to changes in fibrosis by studying patients with stable liver disease. METHODS We performed a retrospective analysis of 531 paired liver stiffness measurements made by Fibroscan when the study began (LSM1) and at follow-up (LSM2), more than 1 day and less than 1 year apart, from 432 stable (for body mass index, waist circumference, and alcohol consumption), untreated, immunocompetent patients with chronic liver disease (from January 2006 through March 2009). Variations between the first and follow-up measurements were expressed as absolute (LSM2-LSM1, kPa) or relative ([LSM2-LSM1]/LSM1*100) or as changes in fibrosis stage. RESULTS There was >20% variation in 49.7%, >30% in 34.3%, and >50% in 12.2% of paired measurements; this variation was constant across the spectrum of LSM1 values. The variations produced a 1-fibrosis stage difference in 31.5% of pairs and a ≥ 2-stage difference in 9.8% of pairs. Patients with LSM1 >7 kPa had increased probability of having a different stage of fibrosis at LSM2, compared with patients with LSM1 <7 kPa. Factors associated with variation included measurements made by 2 different operators or at least 1 non-senior operator, ratios of interquartile range:median values, significant fibrosis (≥ 7 kPa) at LSM1, baseline body mass index, or a 2-fold difference in level of alanine aminotransferase between measurements. When the analyses were restricted to measurements made by the same operator, the variation was slightly reduced; fibrosis stage differed between measurements for only 34.3% of cases. CONCLUSIONS Operator-related and patient-related factors produce significant variations in liver stiffness measurements made by transient elastometry, limiting its use in monitoring patients. These variations are unrelated to disease progression. The lowest levels of variation occur in measurements made in patients with no or early-stage fibrosis or by a single experienced operator.