Blood Chemistry Panel

[Jeff]

Special thanks to the Author: Patricia Gail Burnham and Dog World Magazine for permission to post this very informative article. This article was published in the March 2000 issue of Dog World http://www.dogworldmag.com

 

Making Sense of A Blood Chemistry Panel

Patricia Gail Burnham

 

One of the most useful veterinary tests is a  laboratory analysis of a dog=s blood.  Veterinarians will generally tell owners the results of tests in general terms, AThe liver values are elevated or the kidney values are high.@  Over the last five years I have become very familiar with blood test values as we have been using them to indicate when we should use ultrasound to look for tumors on my elderly dogs.  This family of dogs has shown a tendency to develop liver tumors, which are first identified by a rise in the bilirubin and alkaline phosphatase values on their blood panels.  When those values go up it is time to ultrasound the abdomen in search of tumors.

I always ask for my own copy of the blood tests which enables me to create a file of blood tests for each dog. If you look at blood tests taken over time you can see which values are increasing.

It also made me curious as the meanings of the various readings so I did a little research and learned that the blood tests performed for dogs can  be divided into two kinds:  chemistry profiles and a CBC (Complete Blood Count).  The chemistry profile measures certain chemicals in the blood while the CBC counts the various types of red and white blood cells.

Blood is 90% water.  Other than that it is made up of living blood cells floating in blood plasma.  The plasma is made up of  the water with three kinds of components dissolved in it.  These three components are 1. Proteins; 2. Salts and ions; and 3. All the metabolites, vitamins, hormones, and wastes that are transported to and from the cells of the body.          The Chemistry profile tests for blood components in these three categories and their normal levels are listed here.

1.  Proteins:

 

Total Protein equals the sum of the albumin and the globulin in the blood.  These two are manufactured in the liver from amino acids in the diet and from the breakdown of body proteins.

!        Normal Adult Range 5.0-7.4 G/L

Albumin is a protein manufactured by the liver and is an indicator of the adequacy of protein in the diet.  It controls nutrient transport of bilirubin, fatty acids, hormones, vitamins, and minerals, and it also controls fluid retention and waste removal.  Its value is raised by shock, dehydration and liver disease.  It is lowered by inadequate protein in the diet, low blood viscosity, kidney disease, diarrhea, loss of blood, or hemorrhage, fever, infection, malignancy, liver disease, pregnancy and lactation.

!        Normal Adult Range 2.4-4.4 G/DL

Globulin is a second protein manufactured by the liver.  It is a larger protein than albumin and carries some hormones, fats, and metals.  Gamma Globulin=s antibodies form part of the immune system.   Globulin levels are elevated in chronic infections, chronic liver disease, and myeloma.  It is low in malnutrition, impaired protein digestion, liver disease, kidney disease, or anemia.

!        Normal Adult Range 1.6-3.6 G/DL

A/G Ratio:  This is the ration of albumin to globulin.  When the ratio is out of balance the globulin is usually high.

!        Normal Adult Range  0.8-2.0

2.  The Salts and Ions include:

 

Phosphorus is a chemical element and is needed for calcium and carbohydrate metabolism, calcium transport and buffering the pH of blood and maintaining osmotic pressure.  High levels indicate kidney disease, rapid bone growth, diabetes, excess vitamin D, and liver disease.  Low levels are indicators of vitamin D deficiency, liver disease, and malabsorption, pregnancy and lactation.

!        Normal Adult Range 2.5-6.0 MG/DL

Calcium is essential for teeth and bones.  It is needed for blood coagulation, for the action of many enzymes, regulation of nerves and muscles and to regulate cell wall permeability.  The teeth and bones act as a calcium reservoir.  Calcium moves in and out of teeth and bones as needed to maintain the proper blood calcium level. If the blood level is low, the parathyroid bland hormone pulls calcium out of the bones to add to the blood. What the body is trying to maintain is a ratio between phosphorus and calcium in the blood. .  Elevated Calcium is found in hyperthyroidism, some bone tumors, excess vitamin D or calcium intake.  Low calcium is due to malnutrition, old age, kidney dysfunction, hormone imbalance, vitamin D deficiency, and stress.  

!        Normal Adult Range 8.9-11.4 MG/DL

Calcium/PO4 Ratio: It is the Calcium/Phosphorus ratio that your parathyroid gland is trying to regulate.  A high protein diet will raise the phosphorus level, which stimulates the parathyroid to secrete the hormone which pulls the calcium from the bones and teeth to maintain the optimal calcium/phosphorus ratio.  

!        Normal Adult Range 1.6-5.1

 

Electrolytes are chemical compounds that can divide into electrically charged ions in the blood stream.  Chief among these are positively charged sodium and potassium ions and the negatively charged chloride ions.   A dog gets both sodium and chloride ions from sodium chloride, which is the chemical name for ordinary salt. (When my sister=s routine blood work came back normal except for low sodium and chloride, it indicated that she needed to eat more salt.)  The electrolytes are the chemicals that tie us to the oceans that life was born in.  The salt levels in our blood are the same as those in the sea.  Bicarbonate levels or total carbon dioxide levels are usually included in an electrolyte panel because, while carbon dioxide is a metabolism waste produce, it also acts as a buffering agent.  My vets  routine blood panel for a dog doesn=t test carbon dioxide but I will offer a brief explanation at the end of the electrolyte section in case your laboratory does test for it.

Sodium is an electrolyte that maintains blood pressure, the acid-base balance of blood, production of digestive fluids, and nerve function.  It controls viscosity and ion balance of blood, muscle function and is necessary for growth. .  High salt level can be caused by a high-salt diet, anemia, kidney disease, and liver disease.  When the sodium level of the blood is high the blood tends to be alkaline.  High sodium levels  raise the blood pressure.

!        Normal Adult Range 139-154 MEQ/L

Potassium maintains a cellular fluid balance, and it alkalinizes the blood.  It is needed for electrical conduction in nerves and muscles, including the heart.  An irregular heartbeat is associated with abnormal levels of potassium.  The potassium level is regulated by adrenal hormones, glucose, and sodium.  It is elevated when tissue decomposes.  It regulates the enzymes that control carbohydrate metabolism. Its level is regulated by the kidneys and the adrenal glands.  High potassium levels indicate kidney disease, diabetes, burns, shock, heart attack, slow heart beat and respiratory diseases.  Low potassium levels indicate dehydration, kidney diseaqe, malnutrition, excess

insulin, stress and a high protein diet.

!        Normal Adult Range 3.6-5.5 MEQ/L

NA/K Ratio: The ratio of sodium to potassium in the blood.

 

!        Normal Adult Range 27-38

Chloride: Chloride ions are negatively charged and acidify the blood.  It balances with the Sodium and Potassium positive ions to maintain the balance between acid and alkaline levels in the blood.  High chloride levels make the blood acidic.  (Think of hydrochloric acid.)  Chloride is elevated with acidosis, renal failure, dehydration, hyperventilation.  Low chloride levels and be caused by inadequate dietary salt, vomiting, fluid retention, diarrhea, kidney disease and starvation.

!        Normal Adult Range 102-120 MEQ/L

Carbon Dioxide (CO2 ): Carbon Dioxide is the by product of metabolizing carbon, combining it with oxygen, and releasing energy to your cells.  This is the basic reaction that fuels all animal life.  The carbon dioxide is carried by the blood from the cells where it is produced to the lungs where it is exhaled and exchanged for oxygen.  While it is in the blood it acts as buffer system to control the pH of the blood..  Carbon dioxide is acidic (As in carbonic acid) and it has to be balanced by the positive ions of calcium and sodium.  The body works best when the blood is slightly alkaline so an excess of carbon dioxide in your blood with make you feel really tired.   High carbon dioxide can be caused by severe vomiting, breathing too shallowly to exhale the carbon dioxide, cortisone a part of the bicarbonate and diuretic therapy.   Low carbon dioxide levels are caused by starvation, uremia, and breathing so fast that too much carbon dioxide is exhaled, diarrhea, central nervous system disease and poor liver function.

!         Normal Adult Range 22-29 mEq/L

3. The Enzymes, Hormones, Metabolites and Waste Products in the Blood:

 

Amylase .  Amylases are enzymes that aid digestion by breaking up starches and other carbohydrates into sugars. Amylase is produced by the salivary glands.

!        Normal Adult Range 290-1125 IU/L

Lipase.  Lipases are enzymes that break up the large molecules of  fats and lipids into small segments. Lipase is produced by the pancreas.  (Once, after I had eaten an incredibly high fat breakfast, the blood bank called me for a plasma donation.  The technician overseeing the donation complained repeatedly about how lipimic my plasma was.  There was a layer of fat floating on the surface of the plasma.  Lipid means fat.  Fats are carried in the blood on lipoproteins.  We are all familiar with the terms high density (good ones) and low density lipoproteins (HDL and LDL.).  However elevated levels of Amylase or Lipase are fairly non-specific and can indicate a variety of diseases.

!        Normal Adult Range 77-695 IU/L

Glucose (also called dextrose) is blood sugar.  It provides the main source of energy to the body cells.  (Caffeine gives you energy by stimulating the liver to dump more glucose into your blood.)  The sugar levels in the blood are regulated by both sugar inhibitors and stimulators.  Insulin and glucagon are produced by the pancreas.  Thyroid hormone, liver enzymes and adrenal hormones also control your dog=s glucose levels.  Insulin lowers and glucagon raises the sugar level.  The liver converts glycogen, proteins, and fats into glucose.   Glucose will be high in diabetes, liver disease, obesity, hyperthyroidism, food sensitivities, stress, pancreatitis, or a recent meal high in sugar and starches.  

Low glucose levels indicate excess insulin, liver disease, malabsorption, or hypothyroidism.

 !        Normal Adult Range 70-138 MG/DL

 

AST (SGOT):  SGOT stands for Serum Glutamic Oxaloacetic Transaminase which is an enzyme found in cells of the heart, liver, kidney, pancreas, and muscles.  If any of these tissues are damaged this enzyme blood level rises.  It is a particularly good indicator of liver or heart damage.  In humans it is used as an indicator of heart attack as it may rise by a factor of twenty times normal in the first day after a heart attack.  Pregnancy and vitamin-B deficiency will lower the SGOT

.!        Normal Adult Range 15-66 IU/L

ALT (SGPT):  SGPT stands for Serum Glutamic Pyruvic Transaminase.  This  is an enzyme that is found mainly in liver cells.  It rises with liver damage, kidney infection, chemical pollutants, or heart up with liver disease or gall stones and goes down with stress, fatigue, or adrenal gland exhaustion.

!        Normal Adult Range 12-118 IU/L

CPK stands for Creatin Phosphokinase.  It is an excellent monitor for heart attacks.  

!        Normal Adult Range 102-120 MEQ/L

GGT stands for Gamma Glutamyl Transpeptidase.   This is yet another enzyme found in the liver.  It is elevated in liver disease, bile-duct obstruction, and pancreatitis.  It is lowered in hypothyroidism, hypothalamic problems, or magnesium deficiency.

!        Normal Adult Range 1-12 IU/L

 

Alkaline Phosphatase:  This is the enzyme that was the best marker for liver tumors in my dogs.   It is produced in the cells of the bone or liver.  The level rises during liver degeneration or cell damage, growth or repair.  With an old dog we are concerned about rising levels caused by cell damage.  When the liver enzymes are normal but the Alkaline Phosphatase is high, then it indicates minerals are being moved into or out of the bones and a bone disease is a possibility.  Pregnancy, growth and bone injuries will raise the Alkaline Phosphatase.  It is highest among young, growing dogs.  Alkaline Phosphatase is lowered by malnutrition, protein deficiency, magnesium, B12 or vitamin C deficiency, anemia, or hypothyroidism

!        Normal Adult Range 5-131 IU/L

Cholesterol: The liver produces most of the cholesterol in the blood. (This is bad news for people who are trying to control their cholesterol by using a low fat diet.)  Additional cholesterol is absorbed from food.  High cholesterol levels are associated with various kinds of heart disease and are a risk factor for heart disease in humans.   Cholesterol isn=t always bad.  It is needed for the body to produce natural steroid hormones.  Cholesterol is high in diabetes, liver disease, heart disease, kidney disease, hypothyroidism, and pregnancy.  It is lower in malnutrition, hyperthyroidism, liver insufficiency, malignancy, anemia, and infection.

!        Normal Adult Range 92-324 MG/DL

 

BUN means Blood Urea Nitrogen which is one of the end products of protein metabolism in the body.  Protein foods are first broken down into amino acids.  When the amino acids are metabolized, the remaining nitrogen becomes a part of urea, which is formed in the liver and excreted by the kidneys.  A high protein intake with raise the BUN slightly.  It will also be elevated by kidney damage, dehydration, intestinal bleeding, some drugs and heart failure. The BUN is lowered by a low protein diet, malnutrition, poor protein absorption, liver damage, pancreas or adrenal inactivity and pregnancy.   The most frequently seen change in BUN is the elevation that is caused by kidney disease. The kidneys are endowed with a lot of extra capacity and an animal has to have already lost 75% of its kidney function before the BUN will rise on a blood test.  This means that a good BUN level does not mean that a dog has good kidney function.  It just means that he is not down to his last 25% of kidney function yet.   And conversely, an elevated BUN means that the dog may have already lost three quarters of his kidney function.  

!        Normal Adult Range 6-25 MG/DL

Creatinine is a waste produce of muscle metabolism.  When protein digestion is impaired, the body breaks down muscle tissue to supply amino acids.  (This is the reason that super low protein diets destroy muscle mass.) The Creatinine is excreted by the kidneys so the Creatinine level goes up in kidney disease or muscle degeneration.  It is lowered by some forms of kidney damage, impaired protein digestion, liver disease, protein starvation or pregnancy.

!        Normal Adult Range 0.5-1.6 MG/DL

BUN/Creatinine Ratio:   When the ratio is very high, then too much BUN is being formed.  If the ratio is very low then the Creatinine is not being excreted by the kidneys.  It is a measure of kidney function and protein metabolism and intake.

attack.  It is lowered by poor oxygen transport to the tissues.

!        Normal Adult Range 4-27

Total Bilirubin:  Bilirubin is an indicator of liver function. When red cells die, their hemoglobin becomes bilirubin and is transported to the liver where it is converted to bile and is passed down the bile ducts to the intestines. Bilirubin is what gives feces their brown color.  It also produces the yellow color in the skin and whites of the eyes when jaundice is present, caused by poor liver function. Total bilirubin goes up in liver disease, bile-duct obstruction and hemolytic anemia.  It is low if the spleen or liver are functioning at a low level.  A diet low in nitrogen can lower the bilirubin level.

 

!        Normal Adult Range 0.1-0.3 MG/DL

There can be a variation in the normal ranges from laboratory to laboratory.  The values given here are 1999 values from my vet=s lab.  Your  lab=s normal range will be printed next to the dog=s test value on the report.  So check the values for your own laboratory.  If their test protocols differ, so may their normal ranges.  However they are not likely to differ by much.  It is interesting that the normal ranges for human beings are very close to the normal ranges for dogs.  Even changing the species doesn=t change the normal values for blood by much.        

I wouldn't try to memorize any of the above data but instead would keep a copy of the article in a file with copies of my dog's blood work.   That way the reader can refer to the specific item that is abnormal and determine its significance.