Liver is the largest internal organ in our body situated in the right upper corner of the abdomen. It performs various important functions like bile production and excretion, excretion of bilirubin, cholesterol, hormones, and drugs, metabolism of fats, proteins, and carbohydrates, enzyme activation, storage of glycogen, vitamins, and minerals and synthesis of plasma proteins, such as albumin, and clotting factors.
Liver function test (LFT), help determine the health of your liver by measuring the levels of proteins, liver enzymes, and bilirubin in your blood. They can also monitor the side effects of your medications and assess the severity of liver disease.
Depending on the higher- or lower-than-normal levels of these enzymes or proteins can alert doctors of potential problems such as liver cancer, fatty liver disease, or hepatitis. These tests may be combined with imaging studies like ultrasound, CT scan and also liver biopsy to rule of specific liver infections and diseases.
LFT Panel consists of various tests as follows:
1. Alanine aminotransferase (ALT) / SGPT -
Most specific enzyme for liver and 1 out of 4 enzymes which are part of the LFT. Its levels are increased even prior to clinical signs and symptoms in viral hepatitis and liver damage.
2. Aspartate Aminotransferase (AST) / SGOT -
This enzyme is found in liver, heart, muscle and kidney. This is the second enzyme in the LFT panel. It is elevated in liver damage and disorders of heart, skeletal muscle and kidney. AST:ALT ratio is increased in alcoholic liver disease.
3. Alkaline Phosphatase (ALP) -
This enzyme is found in liver, bones, intestine and parathyroid glands. This is the third enzyme of the LFT panel. It is elevated in disorders of bile duct, liver, bones, intestines and parathyroids. Values are higher in children and adolescents with bone growth.
4. Albumin -
It is the major protein produced by liver. Its levels help in diagnosis and monitoring of nutritional diseases, liver function and kidney function. It is often measured with globulin, another protein and given as ratio (A:G ratio).
5. Total Protein -
Estimation of total proteins help in diagnosis of diseases involving the liver, kidneys, bone marrow and other metabolic or nutritional disorders.
6. Total Bilirubin -
It is produced by breakdown of red blood cells. It is measured as sum of direct and indirect bilirubin. Its levels are increased when the liver is unable to process it normally. Based on which bilirubin is increased, direct or indirect or both, your doctor may be able to pinpoint to the root cause of jaundice and this helps in treatment.
7. Gamma glutamyl transpeptidase (GGT) -
This enzyme is elevated along with other enzymes in liver damage due to various causes. This is a key enzyme, the fourth enzyme in the LFT panel, which is elevated in liver damage caused by chronic alcoholism.
8. Prothrombin time (PT) -
Liver synthesizes most of the protein factors required for blood clotting. In case of liver damage, there is decreased production of clotting factors and prothrombin time is prolonged. Though not a part of Liver Function Test (LFT panel) per se, it is important in measuring the function of clotting factors synthesized by liver like Factor II, V, VII and X, and is part of the liver test packages available.
At Aster Labs, we offer 2 test packages to assess the liver function ie. Liver Function test (LFT), namely LFT Basic and Liver True Care which comprise all the above mentioned tests.