From the Guidelines
Enhanced liver fibrosis (ELF) is a non-invasive blood test that measures specific biomarkers to assess the degree of liver fibrosis, which is the scarring of liver tissue due to chronic liver injury. The test measures three key markers: hyaluronic acid, tissue inhibitor of metalloproteinase-1 (TIMP-1), and procollagen III amino terminal peptide (PIIINP) 1. These markers are involved in the formation and breakdown of extracellular matrix in the liver during fibrosis. The results are combined into a single score that helps clinicians determine the severity of liver fibrosis without requiring an invasive liver biopsy.
Key Points
- ELF testing is particularly useful for monitoring patients with chronic liver diseases such as non-alcoholic fatty liver disease (NAFLD), hepatitis B and C, and alcoholic liver disease 1.
- The test helps physicians make treatment decisions, predict disease progression, and assess response to therapy.
- ELF scores typically range from 0 to 16, with higher scores indicating more advanced fibrosis.
- This non-invasive approach reduces risks associated with liver biopsies while providing valuable diagnostic information about liver health and fibrosis progression.
Diagnostic Approach
- Non-invasive methods such as transient elastography, FIB-4, and NFS are prioritized to discriminate advanced liver fibrosis 1.
- Serological tests, imaging tests, and liver biopsies may be performed as additional liver fibrosis evaluations 1.
Clinical Considerations
- Active use of alcohol may cause false positive liver stiffness measurements (LSM), and AST elevation of more than twice the upper limit of normal (ULN) should raise caution for false positive LSMs 1.
- Repeating the measurement after at least 1 week of abstinence or reduced drinking, in parallel with biochemical retesting, is suggested in patients with elevated liver stiffness and biochemical evidence of liver inflammation 1.
From the Research
Definition of Enhanced Liver Fibrosis
- Enhanced liver fibrosis (ELF) refers to the excessive accumulation of extracellular matrix proteins in the liver, leading to fibrotic scarring as a consequence of chronic injury and inflammation 2.
- Liver fibrosis is characterized by the abnormal accumulation of extracellular matrix components, such as collagens and alpha-smooth actin proteins, expressed by liver myofibroblasts 3, 4.
Causes and Risk Factors
- Liver fibrosis can be caused by various factors, including hepatitis viral infection, alcohol consumption, metabolic-associated fatty liver disease, helminthic infection, iron or copper overload, and biliary obstruction 3, 4, 5.
- Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are currently the leading causes of hepatic fibrosis worldwide 5.
Diagnosis and Management
- The enhanced liver fibrosis (ELF) test is a blood test that measures three molecules involved in liver matrix metabolism to give a score reflecting the severity of liver fibrosis 2.
- The ELF test can be used as a diagnostic test, a prognostic marker, and for disease monitoring, allowing for earlier diagnosis, more accurate prognosis, and personalized treatment 2.
- Other diagnostic methods, such as liver biopsy, transient elastography, and magnetic resonance (MR)-elastography, can also be used to evaluate liver fibrosis 6.
Treatment and Prevention
- While various treatments for liver fibrosis have been investigated, including dietary supplementation, biological treatment, drugs, and genetic regulation, none have been approved by the Food and Drug Administration 3.
- Lifestyle modifications, such as weight loss, exercise, and a healthy diet, are the basis for prevention and treatment of NAFLD-associated fibrosis 5.
- Several promising drug candidates are being developed, targeting metabolic pathways, insulin resistance, hepatocyte death, inflammatory cell recruitment, and matrix expression or turnover 5, 6.