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

Epigenome-Wide Association Study Identifies Methylation Sites Associated With Liver Enzymes and Hepatic Steatosis

BACKGROUND & AIMS

Epigenetic mechanisms might be involved in the regulation of liver enzyme level. We aimed to identify CpG sites at which DNA methylation levels are associated with blood levels of liver enzymes and hepatic steatosis.

METHODS

We conducted an epigenome-wide association study in whole blood for liver enzyme levels, including gamma-glutamyl transferase (GGT), alanine aminotransferase (ALT), and aspartate aminotransferase (AST), among a discovery set of 731 participants of the Rotterdam Study and sought replication in a non-overlapping sample of 719 individuals. Significant DNA methylation changes were further analyzed to evaluate their relation with hepatic steatosis. Expression levels of the top identified gene were measured in 9 human liver cell lines and compared with expression profiles of its potential targets associated with lipid traits. The candidate gene was subsequently knocked down in human hepatoma cells using lentiviral vectors expressing small hairpin RNAs.

RESULTS

Eight probes annotated to SLC7A11, SLC1A5, SLC43A1, PHGDH, PSORS1C1, SREBF1, ANKS3 were associated with GGT and 1 probe annotated to SLC7A11 was associated with ALT after Bonferroni correction (1.0 × 10^-7). No probe was identified for AST levels. Four probes for GGT levels including cg06690548 (SLC7A11), cg11376147 (SLC43A1), cg22304262 (SLC1A5), and cg14476101 (PHGDH), and 1 for ALT cg06690548 (SLC7A11) were replicated. DNA methylation at SLC7A11 was associated with reduced risk of hepatic steatosis in participants (odds ratio, 0.69; 95% CI= 0.55-0.93; P value: 2.7 × 10^-3). In functional experiments, SLC7A11 was highly expressed in human liver cells; its expression is positively correlated with expression of a panel of lipid-associated genes, indicating a role of SLC7A11 in lipid metabolism.

CONCLUSIONS

Our results provide new insights into epigenetic mechanisms associated with markers of liver function and hepatic steatosis, laying the groundwork for future diagnostic and therapeutic applications.

Serum liver enzymes are associated with all-cause mortality in an elderly population

BACKGROUND & AIMS

Little is known about the association of serum liver enzymes with long-term outcome in the elderly. We sought to clarify the association of serum gamma-glutamyltransferase (GGT), alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) with all-cause and cause-specific mortality in an elderly population.

METHODS

This study was embedded in the Rotterdam Study, a large population-based cohort of persons aged 55 years or older. Cox-regression analyses were performed to examine the association of baseline serum GGT, ALP, and aminotransferase levels with mortality, adjusted for age, sex, education, smoking status, alcohol intake, hypertension, diabetes mellitus, body mass index and total cholesterol levels. Liver enzyme levels were categorized according to sample percentiles; levels <25th percentile were taken as a reference.

RESULTS

During a follow-up of up to 19.5 years, 2997 of 5186(57.8%) participants died: 672 participants died of causes related to cardiovascular diseases (CVD) and 703 participants died of cancer. All serum liver enzymes were associated with all-cause mortality (all P < 0.001). Moreover, GGT was associated with increased CVD mortality (P < 0.001), and ALP and AST with increased cancer-related mortality (P = 0.03 and P = 0.005 respectively). Participants with GGT and ALP in the top 5% had the highest risk for all-cause mortality (HR1.55; 95%CI 1.30-1.85 and HR1.49; 95%CI 1.25-1.78 respectively). AST and ALT <25th percentile were also associated with a higher risk of all-cause mortality.

CONCLUSIONS

All serum liver enzymes were positively associated with long-term mortality in this elderly population. Why participants with low ALT and AST levels have higher risk of mortality remains to be elucidated.

FibroTest-FibroSURE™: towards a universal biomarker of liver fibrosis?

Among the noninvasive alternatives to liver biopsy, several studies have demonstrated the predictive value and superior benefit/risk ratio to biopsy of two combinations of simple serum biochemical markers in patients infected with hepatitis B and C virus. These include FibroTest (BioPredictive) for the quantitative assessment of fibrosis, and ActiTest (BioPredictive) for the quantitative assessment of necroinflammatory activity (HCV-FibroSURE, LabCorp). The possible causes of false negatives and positives are also better identified. These tests, which are now available in 12 countries, can facilitate the screening and management of the most frequent liver diseases.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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%.

Non-invasive assessment of liver fibrosis: it is time for laboratory medicine

Chronic liver diseases (CLDs) represent a major cause of morbidity and mortality worldwide. In all etiologies of CLDs, staging of liver fibrosis is essential for both prognosis and management. Until a few years ago, liver biopsy was the only tool for the diagnosis of liver fibrosis in patients with CLDs. However, liver biopsy is an invasive and costly procedure. More recently, various serum biomarkers and laboratory tests have been proposed as surrogates of liver histology. Due to inadequate diagnostic accuracy or to lack of sufficient validation, guidelines still do not recommend them as a substitute for liver biopsy that is still considered the gold standard for the diagnosis of liver fibrosis. Notably, non-invasive serum biomarkers, when combined, may reduce by 50%-80% the number of liver biopsies needed for correctly classifying hepatic fibrosis. However, liver biopsy cannot be avoided completely, but should be used in those cases in which non-invasive methods show poor accuracy. In this view, serum biomarkers and liver biopsy represent a union between laboratory medicine and hepatology.

Biomarkers of liver fibrosis

Liver biopsy, due to its limitations and risks, is an imperfect gold standard for assessing the severity of the most frequent chronic liver diseases. This chapter summarized the advantages and the limits of the available biomarkers of liver fibrosis. Among a total of 2237 references, a total of 14 validated biomarkers have been identified between 1991 and 2007. Nine were not patented and five were patented. FibroTest (FT) was the most studied test with 33 different populations including 6549 patients and 925 controls. The mean diagnostic value for the diagnosis of advanced fibrosis assessed using standardized area under the receiver operating characteristics (ROC) curves was 0.84 [95% confidence interval (CI), 0.83-0.86], without significant difference between the causes of liver disease, hepatitis C, hepatitis B, alcoholic or nonalcoholic fatty liver disease. High-risk profiles of false negative/positive of FT are present in 3% of populations, mainly Gilbert syndrome, hemolysis, and acute inflammation. FT has higher accuracy than aspartate aminotransferase/platelets ratio index (APRI), the most used nonpatented test. No significant difference has been observed between the five patented tests. A quality score has been assessed in order to compare the quality of fibrosis biomarkers. Neither biomarkers nor biopsy are sufficient alone to take definitive decision in a given patient and all the clinical and biological data must be taken into account. Due to the evidence-based data, health authorities in some countries have already approved validated biomarkers as first-line procedure for the staging of liver fibrosis. This overview of evidence-based data suggests that biomarkers could be used as an alternative to liver biopsy for the assessment of fibrosis stage in the four more common chronic liver diseases: C virus (HCV), hepatitis B virus (HBV), hepatitis nonalcoholic fatty liver disease (NAFLD), and alcoholic liver disease (ALD). Neither biomarkers nor biopsy are sufficient alone to take definitive decision in a given patient and all the clinical and biological data must be taken into account.

FibroMAX: towards a new universal biomarker of liver disease?

Among the noninvasive alternatives to liver biopsy, several studies have demonstrated the predictive value and a better benefit-to-risk ratio than biopsy of five combinations of simple serum biochemical markers (the super combination being FibroMAX (BioPredictive, Paris, France) in patients at risk of chronic liver diseases: FibroTest (BioPredictive) for the quantitative assessment of fibrosis; SteatoTest (BioPredictive) for the quantitative assessment of steatosis; ActiTest (BioPredictive) for the quantitative assessment of necroinflammatory activity in chronic viral hepatitis C and B; NashTest (BioPredictive) for the categorical diagnosis of nonalcoholic steatohepatitis; and AshTest for the quantitative assessment of alcoholic steatohepatitis (also known in the USA as HCV-FibroSURE, HBV-FibroSURE, ASH-FibroSURE and NASH-FibroSURE; LabCorp, NC, USA). The possible causes of false-negative and false-positive results are also better identified. These tests, which are now available in 50 countries, can facilitate the screening and management of the most frequent liver diseases.

A prospective analysis of the prognostic value of biomarkers (FibroTest) in patients with chronic hepatitis C

BACKGROUND

FibroTest, a noninvasive method of measuring biomarkers of liver fibrosis, is an alternative to liver biopsy for determining the severity of chronic hepatitis C virus (HCV) infection. We compared the 5-year prognostic value of the FibroTest with biopsy staging for predicting cirrhosis decompensation and survival in patients with chronic HCV infection.

METHODS

Fibrosis stage was assessed on the same day by FibroTest and biopsy in a prospective cohort of 537 patients. Disease classification at baseline was 157 patients with severe fibrosis (FibroTest >0.58), 137 with moderate fibrosis (FibroTest 0.32-0.58), and 243 with no or minimal fibrosis (FibroTest <0.32).

RESULTS

In 64 untreated patients with severe fibrosis, survival without HCV complications was 73% [95% confidence interval (CI), 59%-086%; 13 complications], and survival without HCV-related death was 85% (95% CI, 73%-96%; 7 HCV deaths). Survival rates were higher in patients with moderate fibrosis, [99% (95% CI, 97%-100%; 1 complication; P <0.001) and 100% (no HCV death; P <0.001) for patients with and without HCV-related complications, respectively], and in patients with minimal fibrosis [100% (no complication; P <0.001 vs severe) and 100% (no HCV death; P <0.001 vs severe), respectively]. FibroTest was a better predictor than biopsy staging for HCV complications, with area under the ROC curves (AUROC) = 0.96 (95% CI, 0.93%-0.97%) vs 0.91 (95% CI, 0.85%-0.94%; P = 0.01), respectively; it was also a better predictor for HCV deaths: AUROC = 0.96 (95% CI, 0.93%-0.98%) vs 0.87 (95% CI, 0.70%-0.94%; P = 0.046), respectively. The prognostic value of FibroTest was still significant (P <0.001) in multivariate analyses after taking into account histology, treatment, alcohol consumption, and HIV coinfection.

CONCLUSION

The FibroTest measurement of HCV biomarkers has a 5-year prognostic value similar to that of liver biopsy.

N/A

N/A

[Serum markers of non-invasive fibrosis in chronic hepatitis C virus infection]

MATTER: Liver biopsy is recommended for the management of patients infected by hepatitis C virus (HCV) and is currently the gold standard in assessing liver histology. It's an invasive test prone to complications with a morbidity rate of 0.3 to 0.6% and a mortality rate up to 0.05%. Since the last decade, researchers developed non invasifs biomarkers of liver fibrosis as an alternative to liver biopsy. These scores are based on different algorithms with various combinations of biomarkers issued from extra-cellular matrix, serum and cells.

CURRENT EVENTS

The diagnostic performance of these scores, estimated by the AUROC for significant fibrosis (>F2), in patients with chronic hepatitis C reach 0.78 to 0.90 for the most accurate. In HIV-HCV co-infected patients and patients with hepatitis C cirrhosis the diagnostic performance of these scores reach 0.74 to 0.88 and 0.73 to 0.97 respectively.

PERSPECTIVES

Liver fibrosis biomarkers constitutes an alternative to liver biopsy due to their non invasive approach, their easy reproducibility and accuracy. However, these scores must be used only after a validation in multicentric independent studies. The future is based on the comparison and validation of these scores after laboratory methods standardization.

The diagnostic value of biomarkers (AshTest) for the prediction of alcoholic steato-hepatitis in patients with chronic alcoholic liver disease

BACKGROUND/AIMS

The aim was to identify a panel of biomarkers (AshTest) for the diagnosis of alcoholic steato-hepatitis (ASH), in patients with chronic alcoholic liver disease.

METHODS

Biomarkers were assessed in patients with an alcohol intake>50 g/d, in a training group, and in two validation groups. Diagnosis of ASH (polymorphonuclear infiltrate and hepatocellular necrosis) and its histological severity (four classes: none, mild, moderate and severe) were assessed blindly.

RESULTS

Two hundred and twenty-five patients were included, 70 in the training group, 155 in the validation groups, and 299 controls. AshTest was constructed using a combination of the six components of FibroTest-ActiTest plus aspartate aminotransferase. The AshTest area under the ROC curves for moderate-severe ASH was 0.90 in the training group, 0.88 and 0.89 in the validation groups. The median AshTest value was 0.005 in controls, 0.05 in patients without or with mild ASH, 0.64 in moderate, and 0.84 in severe ASH grade 3, (P<0.05 between all groups). At a 0.50 cut-off, the sensitivity of AshTest was 0.80 and the specificity was 0.84.

CONCLUSIONS

In heavy drinkers, AshTest is a simple and non-invasive quantitative estimate of alcoholic hepatitis. The use of AshTest may reduce the need for liver biopsy, and therefore allow an earlier treatment of alcoholic hepatitis.

Non-invasive diagnosis of large oesophageal varices with FibroTest in patients with cirrhosis: a preliminary retrospective study

BACKGROUND AND AIMS

Primary prevention of variceal bleeding with beta-blockers improves survival in patients with large oesophageal varices (LOV). Therefore, cirrhotic patients frequently undergo screening endoscopy. As portal hypertension is related to liver fibrosis, this study aimed to assess the predictive value of FibroTest, a non-invasive marker of liver fibrosis, for the diagnosis of LOV in cirrhotic patients.

METHODS

Ninety-nine cirrhotic patients had clinical examination, blood sample (liver function tests, platelet count, FibroTest) and upper endoscopy. Measurements of endoscopic and biochemical parameters were made blindly. Sensitivity, specificity, predictive values and area under the receiver operating characteristic curves were assessed for FibroTest, platelet count and Child-Pugh score. The main endpoint was the presence of LOV.

RESULTS

Platelet count, prothrombin time, ascites, FibroTest and Child-Pugh class were significantly different among patients with or without LOV. FibroTest had the highest discriminative power with an area under receiver operating characteristics curves of 0.77 (SE=0.06), compared with 0.64 (0.08) and 0.68 (0.08) for platelet count and Child-Pugh score, respectively (P=0.08). A cut-off at 0.80 had a 86% negative predictive value for the diagnosis of LOV (Se=92%, Sp=21%).

CONCLUSION

FibroTest could aid in the diagnosis of LOV and may therefore reduce the indication of endoscopic screening in cirrhotic patients.

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 Group 1 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.

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.

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.

Autoimmune liver disease

PURPOSE OF REVIEW

This review aims to demonstrate how recent insights into disease behavior and mechanisms and the availability of new drugs can be assimilated into evolving concepts of diagnosis and treatment.

RECENT FINDINGS

Autoimmune hepatitis has a global distribution, and its clinical manifestations are similar in different regions. Concurrent immune diseases are common, and immunoglobulin A nephropathy may explain ascites in some patients. Subclinical celiac disease can cause cryptic liver dysfunction or be associated with autoimmune hepatitis. A fulminant presentation that is associated with de novo rather than exacerbated pre-existent disease is possible, and these patients may have centrilobular zone 3 necrosis. Bile duct injury as a background histologic finding should not change the diagnosis or therapy, and the clinical significance of autoantibodies can be determined only by examination of liver biopsy tissue. Molecular mimicry may be important in breaking self-tolerance, and a murine model based on DNA immunization with self-antigens supports this hypothesis. Corticosteroid therapy reduces or prevents hepatic fibrosis, and noninvasive techniques promise to facilitate the development of treatments that enhance this effect. Mycophenolate mofetil is a possible salvage therapy that requires clinical trial, and liver transplantation has a 5-year patient survival of 78% but is frequently followed by recurrent disease and acute rejection.

SUMMARY

Autoimmune hepatitis should be considered in all patients with acute or chronic liver disease. Therapy can reduce or prevent fibrosis. The new immunosuppressive drugs should undergo clinical trial before empiric use. Animal models promise to identify key pathogenic sites that can be targeted by therapies.

Biomarkers for the prediction of liver fibrosis in patients with chronic alcoholic liver disease

BACKGROUND & AIMS

The aim of this study was to determine the diagnostic use of noninvasive markers of fibrosis in patients with chronic alcoholic liver disease.

METHODS

A total of 221 consecutive patients with an alcohol intake of >50 g/day (median, 100 g/day) and available liver biopsy examination and FibroTest FibroSure (FT) results were included prospectively. Fibrosis was assessed blindly on a 5-stage histologic scale similar to that of the METAVIR scoring system. Hyaluronic acid was measured and used as a standard serum marker of fibrosis.

RESULTS

Advanced fibrosis (F2-F4) was present at biopsy examination in 63% of patients. The mean FT value (SE) was F0 = .29 (.05); F1 = .29 (.03), F2 = .40 (.03), F3 = .53 (.04); and F4 = .88 (.02) (P < .05 between all groups, except between F0 and F1). As opposed to FT, there was no significant difference for hyaluronic acid between F2 and F1 and between F2 and F0. For F2-F4 vs. F0-F1, the FT area under the ROC curves (AUROC) = .84 (.03) and .79 (.03) for hyaluronic acid. For the diagnosis of F4, the AUROC was very high, .95 for FT and .93 for hyaluronic acid. The discordances of the 2 stages were attributed to biopsy failures in 26 cases and to FT failures in 13 cases.

CONCLUSIONS

In heavy drinkers, FT is a simple and noninvasive quantitative estimate of liver fibrosis. The use of FT may decrease the need for liver biopsy examination.

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.