Liver tests & FIB-4
Also known as:
ALT, AST, Fibrosis-4 index
Simple blood tests and a free calculation that flag fatty liver patients who need a closer look.
Written and reviewed by Farhan Tahir, MD · Last reviewed
VIDEO LESSON
What they measure
ALT and AST are liver enzymes. FIB-4 combines age, AST, ALT and platelet count to estimate the likelihood of advanced liver scarring.
Reading FIB-4
• Below 1.3: low risk of advanced fibrosis; repeat periodically
• 1.3 to 2.67: indeterminate; elastography is the next step
• Above 2.67: high risk; specialist evaluation
Good to know
Normal liver enzymes do not rule out fatty liver or fibrosis. FIB-4 is less accurate under 35 and over 65.
Key studies and references
Educational content only, written and reviewed by Farhan Tahir, MD. It does not replace individual medical advice. For sudden chest pain, trouble breathing or stroke symptoms, call 911.
AT A GLANCE
Test type
Liver & body composition
Also known as
ALT, AST, Fibrosis-4 index
Reviewed by
Farhan Tahir, MD
Questions about your own care?
Dr. Tahir’s team offers consults through Youthful Medicine.
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