Liver Disease and Liver Function Testing (July 7, 20011)
Liver disease is a broad term that describes any problem with liver functioning resulting in illness. When the liver is scarred, the term cirrhosis is used to describe the problem due to scarring. To determine the cause of improper liver functioning or whether the problem relates to the liver, various blood tests can be performed, starting with the Basic Health Screening (CMP, CBC, & UA)
. A blood test such as the Basic Health Screening or the Liver Function Test
measures specific levels enzymes in the blood to determine the problems with the liver.
Albumin is one of two serum proteins the liver secretes during healthy functioning. A blood test looks at the amount of albumin in the blood. The blood should have a total of 6 to 8 g/dl of total albumin and globulin levels. Between 52 and 68 percent of the total proteins should be albumin if the liver is healthy. Low levels of albumin suggest a poorly functioning liver.
Globulin is the second of the serum proteins produced by the liver. It makes up about 48 to 32 percent of the total serum protein levels in the blood. When added to the albumin, a total of 6 to 8 g/dl is in the blood. This protein helps fight off infections. While low levels of globulin are sometimes associated with poor liver function, some other causes of low levels exist.
Bilirubin, which is also called Total Bilirubin, occurs in the body when the haemoglobin is broken down. The liver clears away bilirubin from the body in normal functioning. If the liver does not clear away this product, jaundice or yellowing of the skin occurs. Poor liver functioning is not the only cause of high bilirubin, but it is one potential cause.
Alkaline Phosphatase is an enzyme in the blood that removes phosphate groups. It is found throughout the human body, but it is primarily located in the liver. High levels of alkaline phosphatase are a sign that the bile ducts in the liver are blocked and not functioning properly.
The GGT liver test
is another blood test that shows the health of the liver. GGTP stands for Gamma-Glutamyltranserase. It is a protein found in the liver and the optimal range for the GGT in the blood is between 20 and 30 U/L. If GGT tests show an elevated level, doctors might test other proteins to determine the problem because it is a sign of multiple liver problems like hepatitis, alcohol abuse, trauma to the liver, diabetes and numerous other problems. If levels are low, doctors test for low magnesium levels, hypothyroidism or hypothalamic malfunction. It is not always liver disease that causes GGT levels to rise or fall.
The LDH enzyme, or lactate dehydrogenase, is found in the blood if tissues are starting to break down in the body. The enzyme is present regardless of the tissue and the liver is not the only organ in the body that might break down and produce the enzyme. If the enzyme is associated with the liver breaking down, doctors will test further to determine the exact cause. High levels of LDH in the blood are often indicative of hepatitis, liver death or cancer in the liver.
SGOT or AST
An SGOT test, which some doctors might call an AST or aspartate aminotransferase test, is another blood test doctors might perform to determine the health of the liver. High levels of SGOT in the blood indicate some type of liver inflammation like hepatitis, cancer or a reaction to medications. This particular enzyme is throughout the body, so it does not necessarily indicate liver disease. Low levels of SGOT suggest a Vitamin B6 deficiency, kidney dialysis or gonadal deficiency.
ALT or SGPT
An ALT (SGPT)
blood test, which is also called an ALT or alanine aminotransferase test, is a method of determining the health of the liver. While some ALT is found throughout the body, it is primarily located in the liver and kidneys, so the test is a fairly accurate method of determining the health of the liver. High levels of ALT in the blood are indicative of viral hepatitis, alcohol abuse, infectious mononucleosis and pancreatitis. Doctors will run further tests to identify the exact culprit of the high ALT levels in the blood. A low level of ALT is related to Vitamin B6 deficiency and is not an indication of liver disease.
All of these blood tests are related to the health of the liver and doctors will often combine tests to determine which type of liver disease to treat.