Giada Sebastiani

Performance of noninvasive markers for liver fibrosis is reduced in chronic hepatitis C with normal transaminases

Summary.u2002 In chronic hepatitis C, biopsy is the gold standard for assessment of liver fibrosis. Few studies investigated noninvasive markers of liver fibrosis in hepatitis C virus (HCV) patients with normal alanine aminotrasferase (NALT). Eighty HCV patients with NALT and 164 HCV patients with elevated alanine aminotrasferase (EALT) who underwent a diagnostic liver biopsy were evaluated for AST‐to‐platelet ratio, Forns’ index, AST‐to‐ALT ratio (AAR), Fibrotest and the recently proposed Fibroindex, using liver histology as reference standard. The primary end‐point was the detection of significant fibrosis (≥F2). Performance of noninvasive markers was expressed as specificity, sensitivity and positive (PPV) and negative (NPV) predictive value, accuracy and area under the receiver operating characteristic curve (AUROC). All noninvasive markers for liver fibrosis tested showed a poorer performance in NALT group than in EALT group. Overall, Fibrotest had the best performance in NALT group, as showed by AUROC of 0.70 and 73.5% accuracy. Performance of AAR, Forns’ index and Fibroindex was poor in NALT group and it was significantly lower than in EALT group for Forns and Fibroindex (AUROC 0.6 vs 0.76 and 0.58 vs 0.74, respectively, Pu2003=u20030.05). In NALT patients, PPV was high for all noninvasive markers (>87%) except for AAR, while NPV was low (<65%), thus none of them was able to reliably exclude significant fibrosis. In conclusion, performance of noninvasive‐markers is significantly reduced in HCV patients with NALT. Liver biopsy may still be needed for many of these cases to correctly stage liver fibrosis. Specific noninvasive tools and possibly combination of markers should be developed and validated in this clinical setting.

Hepatic iron, liver steatosis and viral genotypes in patients with chronic hepatitis C

Summary.u2002 Hepatic iron has been described in hepatitis C virus (HCV) infection as an important cofactor of disease outcome. The mechanisms leading to hepatic iron deposits (HIDs) in HCV patients are partially understood. We investigated HIDs in the liver biopsies of a consecutive series of 242 HCV‐infected patients with well‐compensated liver disease. Serum ferritin was elevated in 20.7% and transferrin saturation in 19.0%, while 38.8% had stainable HIDs indicating that serum markers of systemic iron overload have low sensitivity in predicting HIDs in hepatitis C. A cut‐off value of serum ferritin (350u2003μg/L in females and 450u2003μg/L in males) had good negative predictive value in excluding presence of mild–moderate HIDs (grade II–III). Hepatic iron deposits correlated by multivariate analysis with serum ferritin [odds ratio (OR) 1.008, 95% confidence interval (CI) 1.005–1.011] and albumin (OR 1.15, 95% CI 1.02–1.297). Hepatic iron deposits were more frequent in HCV‐3‐infected cases than in other genotypes (Pu2003=u20030.027) while raised serum iron indices were more frequent in non‐HCV‐3 genotypes (Pu2003=u20030.02). Furthermore, advanced fibrosis (F3–F4 by METAVIR) was more frequent in non‐HCV‐3 genotypes (Pu2003=u20030.04). In HCV‐3 cases there was a close association between HIDs and severe (grade II–III) steatosis (Pu2003<u20030.00001). These results indicate that in well‐compensated chronic hepatitis C HIDs are strongly associated with HCV‐3 and viral‐induced hepatic steatosis, while in the presence of other genotypes they might merely reflect a more advanced stage of liver disease and/or a systemic iron overload. Serum ferritin could identify a subgroup of patients in which the need of venesection could be excluded without liver biopsy.

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

Abstract 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.

Serum biomarkers for the non-invasive diagnosis of liver fibrosis: the importance of being validated

Chronic liver diseases (CLDs), including chronic hepatitis C and B, alcoholic and non-alcoholic fatty liver diseases, represent a major cause of morbidity and mortality worldwide. The progressive accumulation of fi brosis in the liver characterizes the natural history of CLDs and represents the hallmark of the evolution towards hepatic cirrhosis and its end-stage complications (1) . Staging of liver fi brosis is essential to defi ne prognosis and management of CLDs. Classically, two stages of liver fi brosis are considered relevant by guidelines and clinicians since they signifi cantly modify the management of patients: signifi cant fi brosis, as defi ned as ≥ F2 by METAVIR classifi cation, and cirrhosis, as defi ned as F4 by METAVIR. The former is considered a defi nitive indication for antiviral treatment in chronic viral hepatitis B and C, the latter requires a specifi c follow-up for the risk of hepatocellular carcinoma and esophageal varices (2, 3) . Liver biopsy has long been regarded as the gold standard of reference for the staging of fi brosis. However, it has major drawbacks including cost, side effects and risk of underestimation of liver fi brosis stage if sampling is inadequate (4) . Accordingly, in the last 10 years many efforts have been dedicated by the researchers towards the identifi cation of surrogate markers able to provide a non-invasive assessment of fi brosis in the liver. A number of serum biomarkers have been proposed for the non-invasive diagnosis of liver fi brosis (1) . These can be broadly classifi ed in three main groups: 1) direct markers; 2) indirect markers; and 3) patented tests. Direct markers are fragments of the liver matrix components, such as hyaluronic acid (HA) and products of collagen metabolism, produced by hepatic stellate cells during the fi brotic process. This group of biomarkers refl ects the metabolism of hepatic extracellular matrix and has a pathophysiologic rationale. However, a limitation to the clinical use of direct markers of liver fi brosis is that they are not routinely available in all hospital settings. In contrast, indirect markers are biochemical parameters measurable in the peripheral blood that are routinely performed in patients with CLDs. They are indirect expression of liver damage and are not directly involved in the fi brotic process. These include molecules synthesized, regulated or excreted by the liver, such as clotting factors, bilirubin, transaminases and albumin. More recently, direct and indirect biomarkers have been combined in patented tests with the aim of achieving a higher diagnostic accuracy than the single parameters. Among this last group of serum biomarkers, fi ve patented tests have been proposed and investigated in CLDs, including Fibrotest, Hepascore, Fibrometer, Enhanced Liver Fibrosis (ELF) test and Fibrospect (5 – 9) . Interestingly, some studies have suggested that patented tests may perform better than simple, indirect serum biomarkers (10) . However, indirect biomarkers are routinely performed in patients with CLDs, do not require any additional cost and they are easily accessible in clinical practice. In this issue of Clinical Chemistry and Laboratory Medicine, Guechot and colleagues proposed an independent validation of ELF score in a large cohort of patients with chronic hepatitis C. The authors report an area under the curve of 0.78 for signifi cant fi brosis and of 0.85 for cirrhosis that is somehow in line with previous studies (11) . Moreover, they showed that the ELF score performed better than HA and slightly worse as compared to Fibrotest and Hepascore. The validation of patented serum biomarkers is a critical issue for their widespread use in clinical practice. Indeed, the validation of a patented test, independently from the group who commercialized it, increases the credibility in the test itself. The concept of validation should encompass several aspects that become even more critical when dealing with patented serum biomarkers (Table 1 ). First, a patented biomarker should be compared with simple, economic and extensively validated biomarkers, such as AST-to-Platelet Ratio Index (APRI), and it should demonstrate a clear advantage in terms of diagnostic accuracy (16) . Second, since most of the serum biomarkers have been developed and investigated in chronic hepatitis C, dedicated validation studies in other etiologies of CLDs should be carried out (1) . Indeed, each etiology of CLD presents with specifi c pathogenesis, natural history and associated comorbidities. For example, when considering chronic hepatitis C and chronic hepatitis B, the former has specifi c associated comorbidities, such as steatosis and diabetes; the latter is characterized by a more vigorous necroinfl ammation (12) . Third, a careful evaluation of the risk factors for error of a patented biomarker and their frequency should be carried out. Both the clinician and the laboratory professional should be aware of the conditions that may affect the result of the serum biomarker and that may render the provided information unreliable. Among the patented serum biomarkers, Fibrotest has been extensively investigated as regards to conditions that alter its result, including Gilbert syndrome, systemic infl ammation, hemolysis, extraepatic cholestasis (1) . Fourth, serum biomarkers should be specifi cally validated in special populations that are particularly frequent and in

Clinical trial: comparison of weekly once versus twice half-dose weekly administration of pegylated interferon alpha 2b in combination with ribavirin for the treatment of HCV-1 positive patients with chronic hepatitis C

Backgroundu2002 Pegylated interferon (PEG‐IFN) alpha2b is currently used as a once weekly injection in combination with ribavirin for the treatment of chronic hepatitis C.

Development and validation of a nomogram based on clinical factors and standard laboratory tests for prediction of clinically significant liver fibrosis in chronic hepatitis C virus infection.

Objectives Staging liver fibrosis in chronic viral hepatitis C (HCV) patients is essential for prompting surveillance and treatment. The aim of this study was to develop a nomogram, on the basis of simple clinical and laboratory variables, to predict three clinically significant stages of fibrosis (nil–mild, moderate, advanced/cirrhosis), using histology as reference, and to compare its performance with that of FibroTest, a widely used noninvasive fibrosis score. Materials and methods Nomograms are graphical representations of a mathematical formula, used as predictive tools. The study retrospectively recruited 406 HCV patients undergoing liver biopsy. Nomogram was developed in a training set of 252 patients and tested in a validation set of 154 patients. Histology was staged according to the Metavir system. Fibrosis stages were subgrouped as follows: advanced fibrosis/cirrhosis (F3/F4, 24%), nil–mild (F0/F1, 36%), and moderate (F2, 40%). Age at biopsy, aspartate aminotransferase, &ggr;-glutamyl transpeptidase, albumin, platelet count, and prothrombin activity formed the basis for the so-called Fibro-Nomogram, which, in one graphical representation, estimates probability for different stages of fibrosis. Results Areas under the receiver-operating characteristic curves for advanced fibrosis/cirrhosis were similar for training (0.86) and validation sets (0.87). For nil–mild fibrosis, area under the receiver-operating characteristics were 0.81 and 0.79. Compared with FibroTest, Fibro-Nomogram performed slightly better at predicting severe fibrosis (F3/F4) with positive likelihood ratio (LR+) 5.07 (95% confidence interval 3.08–8.37) versus LR+ 3.82 (95% confidence interval 2.56–5.71) for FibroTest. For nil–mild fibrosis, the two tests showed limited but comparable performances. Conclusion In HCV patients, Fibro-Nomogram, an inexpensive and readily available predictive tool, could enable clinicians to interpret patients’ profile, concurrently stratifying patients into three clinically relevant probability categories with good overall performance.