From the Guidelines
Non-Alcoholic Steatohepatitis (NASH) screening and diagnosis can be achieved through a combination of non-invasive tests and liver biopsy.
Methods for Screening and Diagnosing NASH
- Case-finding strategies using non-invasive tests, such as blood-based scores (e.g. FIB-4) and imaging techniques (e.g. transient elastography), can be applied in individuals with cardiometabolic risk factors, abnormal liver enzymes, and/or radiological signs of hepatic steatosis 1, 2.
- Liver biopsy remains the reference standard for the diagnosis of NASH, as none of the available non-invasive tests (NITs) has acceptable accuracy 3.
- Non-invasive diagnostic methods, such as multiomics and novel biomarkers, are being developed to provide more sensitive and specific diagnosis of NASH 4.
Stepwise Approach for Diagnosis
- Blood-based scores: Use scores like FIB-4 to rule-out/in advanced fibrosis.
- Imaging techniques: Use techniques like transient elastography to assess liver stiffness and fibrosis.
- Liver biopsy: Perform liver biopsy in cases where non-invasive tests are inconclusive or to confirm the diagnosis of NASH. It is essential to note that lifestyle modification, including weight loss, dietary changes, and physical exercise, as well as optimal management of comorbidities, are crucial in the management of NASH 1, 2.
From the Research
Screening and Diagnosis Methods for Non-Alcoholic Steatohepatitis (NASH)
The diagnosis of Non-Alcoholic Steatohepatitis (NASH) can be achieved through various methods, including:
- Liver biopsy, which is considered the gold standard for diagnosing NASH and assessing liver fibrosis 5, 6, 7, 8, 9
- Non-invasive serological assays, such as 20-carboxy arachidonic acid (20-COOH AA) and 13,14-dihydro-15-keto prostaglandin D2 (dhk PGD2), which have been found to be potentially accurate for diagnosing NAFLD 5
- Imaging techniques, including: + Three-dimensional magnetic resonance imaging (3D-MRE) 5 + Combination of the FM-fibro index and Liver stiffness measurement (FM-fibro LSM index) 5 + Machine learning algorithm (MLA) tests 5 + Elastography-based techniques, which seem promising for estimating liver fibrosis 6 + Computed tomography (CT), nuclear magnetic resonance (NMR) spectroscopy, and ultrasound, which are non-invasive imaging methods for diagnosing NAFLD 8
- Biochemical panels, such as FibroTest, ELF, Hepascore, FIB-4, NFS, FLI, and ION, which have AUROCs ranging between 0.80-0.98 for detecting advanced fibrosis 6
- Metabolomics, which has emerged as a prominent research topic for investigating biomarkers for liver diseases that are both sensitive and specific 8
- Multi-omics non-invasive approaches, which have been developed and evaluated for assessing NAFLD 9
Non-Invasive Diagnostic Tests
Non-invasive diagnostic tests for NASH and NAFLD-related fibrosis include:
- Non-invasive biomarkers, such as those identified through metabolomics 8
- Imaging techniques, such as 3D-MRE and elastography-based techniques 5, 6
- Biochemical panels, such as FibroTest and FIB-4 6
- Machine learning algorithm (MLA) tests 5
Limitations and Future Directions
Despite the progress in non-invasive diagnostic tests, there are still limitations and challenges in diagnosing NASH and NAFLD-related fibrosis, including: