APRI - Liver Fibrosis Index
The APRI Liver Fibrosis Index Calculator helps you quickly assess liver fibrosis risk. Just enter AST and platelet count to obtain a reference score through the AST-Platelet Ratio Index, with support for FIB-4 combined interpretation and liver elastography recommendations. Use it to assist non-invasive preliminary screening for chronic hepatitis C and NAFLD patients, and stay on top of liver health trends anytime.
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About APRI and Liver Fibrosis Index
About APRI and Liver Fibrosis Index (Definition, Function)
APRI (AST-Platelet Ratio Index) is a non-invasive assessment tool based on blood indicators, primarily used for preliminary screening of liver fibrosis and cirrhosis. The APRI Liver Fibrosis Index Calculator uses the ratio of AST aspartate aminotransferase to platelet count to quickly generate a reference score, helping clinicians and patients understand the degree of liver fibrosis. This tool is especially suitable for long-term follow-up of patients with chronic hepatitis C and NAFLD (non-alcoholic fatty liver disease), and can reduce reliance on liver biopsy. APRI score is often used in combination with the FIB-4 index to improve the accuracy of non-invasive diagnosis, while also providing referral basis for liver elastography (FibroScan).
How to Use the APRI Liver Fibrosis Index Calculator (Steps)
Using the APRI Liver Fibrosis Index Calculator is very simple. Step one, enter the AST aspartate aminotransferase test value (U/L), and adjust the AST upper limit of normal (default 40 U/L) according to the laboratory reference range. Step two, enter the platelet count (×10⁹/L). Step three, click the "Calculate APRI" button, and the tool will immediately display the APRI index, fibrosis risk classification, and clinical interpretation. You can also click "Fill Example" for a quick experience, or use the "Clear" button to re-enter. After calculation, you can copy the result summary with one click for easy recording or sharing. The entire calculation process is completed locally in the browser without uploading data.
APRI Combined with FIB-4 Interpretation and Liver Elastography Recommendations (Knowledge)
APRI score and FIB-4 index are two commonly used non-invasive liver fibrosis assessment tools, and their combination can improve diagnostic sensitivity and specificity. APRI below 0.5 usually suggests significant fibrosis can be excluded; 0.5-1.0 indicates possible fibrosis; 1.0-1.5 indicates significant fibrosis; 1.5-2.0 indicates progressive fibrosis; above 2.0 highly suggests cirrhosis. For patients with intermediate to high risk indicated by APRI, further liver elastography (FibroScan) or referral to a hepatology specialist is recommended. In addition, NAFLD patients should regularly monitor APRI changes and combine with imaging examinations for comprehensive assessment. It should be noted that APRI is only a reference tool and cannot replace liver biopsy or professional medical diagnosis.
APRI Liver Fibrosis Index Calculator FAQ
What is the APRI score?
APRI (AST-to-Platelet Ratio Index) is a blood indicator for non-invasive assessment of liver fibrosis and cirrhosis, calculated from AST and platelet count. WHO recommends it for screening hepatitis C patients in resource-limited areas, and it is also the core indicator of the APRI Liver Fibrosis Index Calculator.
How to interpret APRI results?
APRI<0.5 excludes significant fibrosis; 0.5-1.0 possible fibrosis; 1.0-1.5 significant fibrosis; 1.5-2.0 progressive fibrosis; >2.0 highly suggests cirrhosis. Combining with FIB-4 index can improve accuracy, and liver elastography is recommended when necessary.
What value should be used for the AST upper limit of normal?
Usually 40 U/L is used, but different laboratories may have differences (women may use 35). Please refer to the reference range on your test report. The APRI Liver Fibrosis Index Calculator defaults to 40 U/L, which you can adjust yourself.
What is the difference between APRI and FIB-4?
APRI only uses AST and platelet count, while FIB-4 includes age, AST, ALT, and platelets. The two are often used in combination to improve the sensitivity and specificity of non-invasive liver fibrosis diagnosis. NAFLD patients can calculate both APRI and FIB-4.
Which populations is the APRI calculator suitable for?
It is suitable for preliminary screening of liver fibrosis in patients with chronic hepatitis C, NAFLD (non-alcoholic fatty liver disease), etc. The APRI Liver Fibrosis Index Calculator can assist long-term follow-up, but cannot replace liver biopsy or liver elastography.