Liver Function Test: Purpose & Procedure

Liver function tests (LFTs/LFs) conducted at LivGastro primarily consist of Blood Tests that provide vital information about the condition of a patient’s liver. Some of these tests comprise Prothrombin Time (PT/INR), aPTT, albumin, Bilorubin (both direct and indirect) and a few others. Liver transaminases (AST or SGOT and ALT/SGPT ) provide helpful biomarkers in terms of the types of liver injury a patient has suffered.

As luck would have it, call it ill luck, most liver disorders cause not so intense initial symptoms, while ninety percent of hepatic disease conditions have poor prognosis. However, tests are essential to ascertain the extent of damage caused to the person’s liver to determine the right course of treatment.

While some tests are associated with functionality, such as albumen, there are others that relate to cellular integrity, such as transaminase, while some others are linked to the biliary tract (gamma-glutamyl transferace and alkaline phosphate).

Some biochemical tests are also conducted for evaluation and management of patients with hepatic dysfunction, especially in terms of ascertaining the extent of damage caused to the liver as also the line of treatment that would best suit such patients.

Other tests commonly conducted at LivGastro includes the following:

• 5’ Nucleotidase (5’NTD) which is specific for cholestasis that refers to damage to the intra- or extrahepatic biliary system which is often used as a substitute for GGT in ascertaining if the elevated ALP is of biliary or extrabiliary origin.
• Coagulation Test – The liver is responsible for the production of the vast majority of coagulation factors. In patients with liver disease, INR can be used as a marker of liver synthetic function as it includes factor VII, which has the shortest half life (2-6 hours) of all coagulation factors measured in INR. An elevated INR in patients with liver disease, however, does not necessarily mean the patient has a tendency to bleed, as it only measures procoagulants and not anticoagulants. In liver disease the synthesis of both are decreased and some patients are even found to be hypercoagulable (increased tendency to clot) despite an elevated INR. In liver patients, coagulation is better determined by more modern tests such as thromboelastogram (TEG) or thomboelastrometry (ROTEM).
• Serum glucose Test, also called ‘BG’ or ‘Glu’ is conducted to measure the liver’s ability to produce glucose (gluconeogenesis). In fact, it is the terminal function to be lost in the setting of ‘fulminant liver failure’.
• Lactate dehydrogenase Test – Lactate dehydrogenase or LDH is observes in most body tissues that include the liver. However, elevated LDH levels often indicate liver damage. However, LDH isotype-1 (or cardiac) is often used for estimating damage caused to cardiac tissues, even though troponin and creatine kinase tests are found to be better alternative.