Due to the limitations and the invasive nature of liver biopsy, there has been extensive interest in developing non-invasive tests to measure liver fibrosis (
1). These are alternatives to liver biopsy that can be used in clinical practice, with benefits in terms of cost, risk, and patient convenience (
2). Clinically applicable non-invasive tests include radiological studies, transient elastography (TE), and serum markers. Most noninvasive tests of liver fibrosis were developed with the aim of discriminating between “insignificant”, (F0-F1) by METAVIR and clinically “significant” fibrosis (≥ F2) by METAVIR or for identifying or excluding established cirrhosis in patients with well compensated chronic liver disease. Both these aims are clinically the most relevant (
3). Diagnosing or excluding cirrhosis has major implications for patient outcomes and mandates radiological screening every six months for hepatocellular carcinoma and endoscopy to rule out portal hypertension (
4). Recent radiological advances allow the bedside assessment of liver stiffness with techniques like: TE (
5), acoustic radiation force impulse (ARFI) (
6) and magnetic resonance elastography (MRE) (
7). TE is currently the most widely used and best validated technique for noninvasive assessment of liver fibrosis worldwide, mainly in viral hepatitis. Its diagnostic performance is better for cirrhosis than for significant fibrosis, with mean area under the receiver operating characteristic curve (AUROC) values of 0.94 and 0.84, respectively (
8). TE has also been found as a reliable method for assessment of chronic liver disease of non-viral etiology; such as alcoholic liver disease (
9), nonalcoholic fatty liver disease (NAFLD) (
10) and cystic fibrosis (
11). A variety of direct serum markers of fibrosis, reflecting either the deposition or the removal of extracellular matrix in the liver, have been evaluated for their ability to assess liver fibrosis. They include: glycoproteins such as Alpha-2-Macroglobulin (α2-MG), serum hyaluronate, laminin, and YKL-40; the collagen families such as procollagen III N-peptide and type IV collagen; collagenases and their inhibitors such as matrix metalloproteases and tissue inhibitory metalloprotease-1. Indirect serum markers including simple routine blood tests such as prothrombin index, platelet count, and AST/ALT ratio have also been proposed (
12). Recently genomic and proteomic research provides many candidate biomarkers, but independent validation of these biomarkers is lacking, and reproducibility is still a key concern (
13). Also various tumor markers in serum including α-fetoprotein, carcinoembryonic antigen, cancer antigen 19-9 (CA 19-9), and cancer antigen 125 (CA 125) have been reported to be elevated nonspecifically in liver disease or nonmalignant conditions (
14). The limitations of individual markers to assess liver fibrosis have led to the development of more sophisticated algorithms or indices combining the results of panels of markers that substantially improved diagnostic accuracy for which FibroTest has been the pioneer (
12). FibroTest combines five laboratory parameters (α2-macroglobulin, haptoglobin, apolipoprotein A1, γ-glutamyl transpeptidase (GGT), and total bilirubin) in addition to age and sex. Other widely used panels of biomarkers include: The AST-to-Platelet Ratio Index (APRI), FibroIndex (platelet count, AST, GGT), FibroMeter (platelet count, α2- macroglobulin, AST, age, prothrombin index, hyaluroinc acid (HA), blood urea nitrogen), Forns (age, platelet count, GGT, cholesterol levels), Hepascore (age, gender, bilirubin, GGT, HA, α2- macroglobulin) and Fib-4 (platelet count, ALT, AST, platelet count, age) (
15). More recent biomarker panels include: Fibro-α score (alpha Feto-Protein, aspartate aminotransferase, aspartate aminotransferase/alanine aminotransferase and platelet count) (
16) and FibroSteps (hyaluronic acid, TGF-β1, α2-macroglobulin, MMP-2, apolipoprotein-A1, urea, MMP-1, alpha-fetoprotein, haptoglobin, RBCs, haemoglobin and TIMP-1) (
17).