What Is a Liver Function Test?
Doctors often recommend a Liver Function Test (LFT), also known as a Liver Panel, to assess the health and function of your liver. These blood tests provide important information about liver function and help identify liver diseases, monitor ongoing liver conditions, and evaluate the effectiveness of treatment.
The laboratory report usually includes the reference (normal) ranges for each test. These values may vary depending on age, sex, and the laboratory performing the test. Certain viruses, alcohol consumption, medications, unhealthy diets, and exposure to chemicals can damage the liver and affect these results.
Common Tests Included in a Liver Function Test
Bilirubin
A yellow pigment produced when red blood cells break down. Elevated levels may indicate liver disease, bile duct obstruction, or certain blood disorders, leading to jaundice.
ALT
An enzyme found primarily in liver cells. Elevated ALT usually indicates liver cell injury or inflammation. Common causes:
- Fatty liver disease
- Viral hepatitis
- Certain medications
- Alcohol-related liver damage
AST
Present in liver cells as well as the heart and muscles. Increased levels may indicate liver inflammation or damage, though they can also rise in certain muscle and heart conditions.
ALP
Found in the liver, bile ducts, and bones. Elevated levels may suggest:
- Bile duct obstruction
- Certain liver diseases
- Bone disorders
GGT
An enzyme that often increases in various liver diseases and fatty liver disease. Elevated levels may also be associated with:
- Regular alcohol consumption
- Bile duct disease
- Certain medications
- Excessive artificial sweeteners
Albumin
A protein produced by the liver. Low blood albumin levels may indicate that the liver is not producing proteins efficiently. Levels generally stay normal until significant liver damage has occurred.
Prothrombin Time
Often reported with the International Normalized Ratio (INR), PT measures how long it takes blood to clot. Since the liver produces clotting factors, prolonged PT/INR may indicate impaired liver synthetic function.
Platelet Count
Platelets help with clotting. A low platelet count may be associated with chronic liver disease or cirrhosis. An enlarged spleen, common in advanced liver disease, can also reduce platelet levels.
Additional Tests for Liver Evaluation
If liver damage is suspected, your doctor may recommend additional investigations to get a complete picture of your liver health.
Book a Liver Function TestHepatitis Virus Tests
Hepatitis B, Hepatitis C, and other viral markers.
Liver Ultrasound
Imaging to check liver size, shape, and structure.
FibroScan®
Liver Elastography to measure liver stiffness and fat.
Liver FNAC
Fine Needle Aspiration Cytology in selected cases.
Liver Biopsy
Recommended when a detailed tissue diagnosis is necessary.