1. Health
Send to a Friend via Email

Discuss in my forum

Blood Tests - Liver Function Tests (LFTs)

Measuring the Health of Your Liver

By

Updated June 27, 2007

Liver function tests are a battery of tests that give your doctor an idea of how well your liver is working. From these studies, your doctor can identify possible liver disease, medication stress on liver function, or infections of the liver such as hepatitis. There are several different tests that comprise LFT's.
  • Albumin (ALB)
    Albumin is a protein produced by the liver that helps maintain osmotic pressure in the vascular space. By maintaining this pressure, fluid stays in the vascular system instead of leaking out into the tissues resulting in swelling (edema). Albumin also carries certain minerals in the blood stream.

    Normal values: 4 - 6
    Elevated: Usually indicates dehydration
    Below normal: Can indicate liver dysfunction or insufficient protein intake.

  • Alkaline Phosphatase (ALK PHOS)
    Alkaline phosphatase is an enzyme found in many organs in the body, including the liver.

    Normal values: 30 - 120
    Elevated: A warning sign that there is some type of liver dysfunction resulting in liver tissue damage.
    Below normal: Usually not significant.

  • Alanine Aminotransferase (ALT or SGPT)
    This protein is found primarily in the liver. It is released into the blood when there has been some sort of liver tissue damage.

    Normal values: less than 35
    Elevated: Indicates that liver tissue damage has occurred as a result of infection, medications,obstruction, cirrhosis or injury to the liver.
    Below normal: There is no known disease process that results in a low ALT level.


  • Aspartate Aminotransferase (AST or SGOT)
    This protein is found primarily in the liver. It is released into the blood when there has been some sort of liver tissue damage.

    Normal values: less than 35
    Elevated: Indicates tissue damage as a result of such things as obstruction, hepatitis, or cirrhosis.
    Below normal: Usually not significant

  • Total Bilirubin (TBIL)
    Bilirubin is a normal component of red blood cells. When these cells break down free bilirubin is released in the blood. Bilirubin is then carried to the liver where it is broken down and excreted. When the liver is not functioning properly, bilirubin builds up in the body, causing jaundice (yellowing of the skin and eyes and darkening of the urine).

    Normal values: less than 1.0
    Elevated: usually caused by a dysfunction of the system that breaks down bilirubin which includes the liver. Such an elevation can be caused by an obstruction or liver failure.

  1. About.com
  2. Health
  3. AIDS / HIV
  4. HIV Associated Illnesses
  5. Hepatitis
  6. Hepatitis Basics
  7. Lab Tests - Blood Tests - Liver Function Tests (LFTs) - Liver Function Studies

©2014 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.