FIB-4 Index (Fibrosis-4)
Liver markersWhat the test generally measures, and what to ask about it.
Longetic keeps every lab and record you’ve had organized and easy to find, so your own FIB-4 Index (Fibrosis-4) values sit together on one chart and you walk into your next appointment prepared.
What is FIB-4 Index (Fibrosis-4)?
A calculated score using age and routine blood tests to estimate the likelihood of significant liver scarring (fibrosis).
FIB-4 is a calculated value: it combines your age, two liver enzymes (AST and ALT), and your platelet count using (Age times AST) divided by (Platelets times the square root of ALT). It was developed as a simple, non-invasive way to gauge liver scarring without a biopsy. A higher FIB-4 can be associated with a greater likelihood of advanced fibrosis, a low value makes advanced scarring less likely. It is a risk estimate that guides further evaluation, not a diagnosis.
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