Comprehensive Metabolic Panel

What do the Comprehensive Metabolic Panel lab results mean?

The Comprehensive Metabolic Panel of lab test results look at the general state of the body with special attention to the function of the liver and kidneys.


Glucose is blood sugar. High levels of Glucose (above 140 or so in the fasting state) are usually indicative of diabetes. Low levels are sometimes indicative of “hypoglycemia.”

Urea nitrogen (BUN)

– high Urea nitrogen (BUN) levels are often associated with decreased kidney function or dehydration. Low BUN levels are usually normal.


Creatinine is a by-product of muscle function. Creatinine is a protein and is filtered from the blood by the kidneys. High levels of Creatinine are the best early indicator that the kidneys aren’t working properly.

BUN/Creatinine ratio

– when BUN level is elevated, the BUN/Creatinine ratio helps to determine if BUN elevation is due to dehydration or if it’s due to kidney problems. A low BUN/Creatinine ratio means creatinine is elevated relative to BUN.

Sodium, chloride, and potassium

Sodium, chloride, and potassium are the main salts in the bloodstream and are important indicators of kidney function. Sodium, chloride, and potassium levels can be thrown out of balance (especially potassium) by diuretics (“water pills”).

Carbon dioxide

Carbon dioxide levels are another indicator of kidney function, especially as they relate to the maintenance of the proper pH of the blood (balance between acidity and alkalinity in the body). Low levels of Carbon dioxide are often associated with extreme stress on the body or abnormal kidney function.


– most calcium is in the bones. This test does not measure that. This is calcium in the bloodstream, important for proper function of the muscles. Abnormal calcium levels are usually associated with malfunction of the parathyroid glands, or with severe illness. Often calcium levels will be slightly outside normal ranges associated with either high or low total protein levels. This is because calcium is attached to proteins in the blood. In this case, calcium is probably normal.

Protein, total

proteins are the “building blocks” of the body. Proteins are an indicator of body metabolism and general health of the liver and immune system. Protein level is the sum of the body’s albumin and globulin levels.


Albumin is a protein produced by the liver. Low levels of Albumin are associated with liver disease.


Globulin is produced by the immune system (cells from the bone marrow). There are many types of globulin that can be measured separately to determine what type of disease is going on if the globulin levels are abnormal.

Albumin/globulin ratio

Albumin/globulin ratio helps to discern if there is a problem with either globulin or albumin when the total protein is abnormal.

Bilirubin, total

Bilirubin is a by-product of the breakdown of hemoglobin. Hemoglobin is the red pigment that carries oxygen in red blood cells. Bilirubin is a protein processed by the liver and excreted in the digestive tract through the gallbladder in bile. Elevated levels usually indicate a problem with the liver’s ability to process bilirubin either through increased breakdown of red cells, or, more often, liver disease such as hepatitis. Greatly elevated bilirubin levels cause jaundice.

Alkaline phosphatase (ALK PHOS)

Alkaline phosphatase is an enzyme found in the cells that line the ducts of the liver and also in bone. High levels of Alkaline phosphatase can be an indicator of blockage in the liver, or damage to bone. A further test can be run to tell the difference between bone or liver alk phos.




AST (SGOT) and ALT (SGPT) are two enzymes found within the cells of the liver. Elevations of AST (SGOT) or ALT (SGPT) enzymes can indicate stress on the liver (as can be caused by some medications or alcohol) or actual damage to liver cells (as in hepatitis, cirrhosis, or other liver disease).


GGT is another liver enzyme frequently included in the “liver panel.” GGT is a most sensitive indicator of liver stress or damage (even in the past) and is often elevated in patients who have had liver disease in the past or who are presently on a medication, drinking excess alcohol, or exposed to something that is putting stress on the liver.


TSH is a hormone from the pituitary gland in the brain that tells the thyroid gland to produce thyroid hormone. Thyroid hormone is essential for almost every function in the body. If the thyroid is not producing enough thyroid hormone, the pituitary will produce more TSH. Therefore, high TSH is the easiest way to diagnose inadequate thyroid function.