Testing the Liver
The liver is a vital body organ, and humans cannot survive without it. There are many conditions that can affect the functioning of the liver, so doctors may feel the need to investigate it. Those who abuse alcohol can develop a condition called alcoholic liver disease. The Liver Function Test (LFT) provides important information about the state of this part of the body. It involves taking a sample of blood and having this tested in a laboratory.
The Functions of the Liver
The liver can be found in the right upper quadrant of the abdomen. It is just below the diaphragm. It is the largest gland in the body and weighs over 3 pounds. The liver performs a number of functions that are vital for human health and these include:
* It makes special proteins that the body needs for blood clotting and processing fats during food digestion.
* It stores glycogen which can later be used by the body to produce energy.
* This organ also stores vitamins and minerals including iron, copper, vitamin A, Vitamin B12, and Vitamin D.
* The liver plays a vital role in removing toxins from the body. If these toxins are not removed, the individual will become very sick.
* This organ is also responsible for drug metabolism.
* The liver breaks down insulin.
* It turns ammonia into urea.
* It makes bile which is required for digesting lipids.
* The liver works as part of the immune system by producing cells that join with antigens.
Liver Function Tests Results
The liver function blood test looks at the levels of certain chemicals within the bloodstream. These chemicals are of interest because they can be indicative of problems with the liver. The results that are of interest to doctors are:
* Alkaline phosphatase (ALP) is an enzyme found in liver biliary ducts and in bone. If ALP levels are high, it could indicate a large bile duct obstruction.
* Albumin is one of the proteins made by the liver. This chemical tends to be low in people who have some type of chronic liver condition. It can also be a sign of poor nutrition.
* Aspartate aminotransferase (AST) is an enzyme that can be found in cells inside the liver. If the liver is damaged, there will be high levels of AST in the blood results. A large amount of this enzyme in the blood stream isn’t always indicative of liver problems, though. It is also produced when the heart or skeletal muscle is damaged.
* Bilirubin is what gives a yellow color to bile. If it gets too high in the blood stream, it can be very noticeable. Jaundice causes people to develop a yellowish or orangish color on their skin and the whites of their eyes. A high level of bilirubin could indicate a blockage in the bile duct, or a disease process that is causing the red blood cells to be broken down too quickly.
* Alanine transaminase (ALT) is an enzyme that is required to break down protein by speeding up chemical reactions. If the liver is inflamed, there will usually be high levels of ALT in the blood stream. This inflammation could be due to an injury or disease process.
* Gamma glutamyl transpeptidase (GGT) is another enzyme associated with the liver. High levels of this can indicate cholestatic damage or alcohol toxicity.
Liver Function Test Results and Alcoholic Liver Disease
One of the complications of alcoholism is alcoholic liver disease. It is not completely understood why some alcoholics develop a problem with this organ; although, it is generally believed to be due to the toxic properties of alcohol along with poor nutrition. Up to one in five of those who develop alcoholic liver disease will go on to develop cirrhosis.
Until the stage of cirrhosis is reached, it is possible for the liver to repair itself. During the early stages of alcoholic liver disease, there may be few noticeable symptoms. This means that the liver can become damaged beyond repair before the individual becomes aware of any problems. Liver function test results help diagnose the problem before it becomes too late.
An individual who is abusing alcohol may exhibit an isolated rise in GGT. This enzyme should return to normal levels in the blood stream if the person stops drinking for a few weeks. A rise in AST and ALT could indicate alcoholic hepatitis or cirrhosis of the liver.