As we all know, pets can’t tell us how they’re feeling. It’s usually how they look or act that alerts us that something is wrong. As their owner, you play a very important role in helping them stay as healthy as possible and combat illness. Being aware of the warning signs that your pet may be sick is key. In addition, the best way to ensure that your pet lives a long, happy and healthy life is regular preventive health screens, including a physical exam and blood work.
When is blood work necessary?
Sick and emergency situations. Blood work provides a valuable picture of your pet’s health and is often the first step when pets are brought in for a sick or emergency visit. It helps the veterinary staff make immediate decisions, so they can quickly help your pet.
Preanesthetic screening. Blood work is routinely done prior to your pet’s surgery, dentistry, or other procedures that require anesthesia. This lets the veterinary staff know if anesthesia is safe for your pet and allows them to make adjustments if they see anything abnormal. This screening is usually done on the same day as the procedure, to make it easier on you and your pet.
Preventive Care Screening. Even though no one knows your pet better than you do, sometimes the signs of being sick just aren’t obvious. Therefore, preventive care blood work is recommended as part of your pet’s annual exam. When discovered early, many diseases can be treated successfully, giving pets a better chance at full recovery. In addition, preventive care screening can help you avoid significant medical expenses and the stress associated with them.
Medication Monitoring. Some medications have the potential for side effects. Periodic blood work may be required while your pet is being treated to watch for any abnormalities. This will allow your veterinarian to make any necessary changes before problems arise. Other medications require blood tests to ensure that the appropriate dosage is being administered.
What tests might my veterinarian run?
Complete Blood Count (CBC): Lets us know if your pet has an infection, if inflammation is present, or if your pet is anemic.
Complete Blood Chemistry Panel: Includes electrolytes; provides information about your pet’s liver, kidneys and pancreas, as well as other bodily functions, such as blood sugar and hydration.
Urinalysis: Performed on a sample of urine; identifies an infection or inflammation in the urinary tract.
Thyroid Function Test: Detects whether or not your pet’s thyroid gland is functioning properly. Thyroid disease is very common in older cats and dogs.
Heartworm Test/4DX: Performed annually to check for Heartworm Disease, Lyme Disease, and two other tick-borne diseases: Ehrlichiosis and Anaplasmosis. Required with the use of monthly heartworm preventive medications.
Pancreatic Lipase: Tests for pancreatitis in both dogs and cats.
FIV/FeLV: Tests for Feline Immunodeficiency and Feline Leukemia Virus, two of the major causes of illness and death in cats.
Your veterinarian may recommend additional tests.
Understanding Your Pet’s Blood Work
BUN (blood urea nitrogen)— increases may be seen with decreased kidney function, dehydration, heart disease, shock or urinary obstruction, as well as following a high protein diet; decreases may be seen with over hydration.
CREA (creatinine)—increases may be seen with decreased kidney function and other conditions as noted with BUN, but is not affected by a recent high protein diet; decreases may be seen with over hydration.
PHOS (phosphorus)—elevations are seen with decreased kidney loss through conditions like kidney disease, increased intake through the gastrointestinal tract and increased release from injured tissues; increases in growing puppies and kittens can be normal; decreases may be seen with increased loss or decreased intake.
Ca+ (calcium)—increases may be seen as a result of a variety of diseases including kidney disease, certain cancer types, certain toxicities and parathyroid disease; decreases may be seen with certain parathyroid diseases and with low albumin.
ALT (alanine aminotransferase)—increases are a sensitive indicator of liver cell damage.
ALKP (alkaline phosphatase)—increases may indicate a liver abnormality (cholestasis), Cushing’s disease, active bone growth in young pets, active bone remodeling after bone injury; may be induced by multiple drugs and nonspecific conditions.
GGT (gamma glutamyl transferase)—increases may indicate a certain type of liver abnormality (cholestasis)
ALB (albumin)—increases may indicate dehydration; decreases may be seen with decreased liver function, blood loss, gastrointestinal disease or kidney disease.
TBIL (total bilirubin)— increases may be seen with liver disease (cholestasis and insufficiency) and certain types of anemia.
Bile acids—increases in this blood component may be an indication of decreased liver function, abnormalities in blood flow to the liver, or possible bile duct obstruction.
AMYL (amylase)—increases may be seen with pancreatitis, kidney disease, gastrointestinal disease or certain drug treatments; degree of change and other laboratory data may help identify pancreatitis specifically.
LIPA (lipase)—increases may be seen with pancreatitis, kidney disease, gastrointestinal disease and certain drug treatments; degree of change and other laboratory data may help identify pancreatitis specifically.
TP (total protein)— increases may indicate dehydration or an inflammatory condition; decreases may be seen in decreased liver function, blood loss, gastrointestinal loss and kidney loss.
ALB (albumin)— increases may indicate dehydration; decreases may be seen with decreased liver function, blood loss, gastrointestinal disease and kidney disease.
GLOB (globulin)—increases may be seen with inflammation and potential chronic infection; decreases may be seen with blood loss, gastrointestinal loss, and immune deficiencies.
Na+ (sodium)—increases may indicate dehydration; decreases may be seen with loss during diarrhea and vomiting or with Addison’s and kidney disease.
K+ (potassium)—increases may indicate kidney disease due to decreased excretion, with Addison’s disease, dehydration, and kidney obstruction; decreases may be seen with loss during diarrhea or vomiting.
Cl- (chloride)—increases may indicate dehydration; decreases may be seen with loss during diarrhea or vomiting.
GLU (glucose)—increases may indicate diabetes mellitus; decreases may be due to liver disease, pancreatic disease and other conditions and could lead to collapse, seizure or coma.
AST (aspartate aminotransferase)— increases are associated with liver or muscle damage.
CK (creatine kinase)—increases are associated with muscle damage.
CHOL (cholesterol)— increases may be seen with a variety of metabolic disturbances including diabetes mellitus, hypothyroidism, Cushing’s disease, pancreatitis and some types of kidney disease; decreases may be seen with liver insufficiency and intestinal disease.
TRIG (triglycerides)— increases may be seen in a variety of conditions including non-fasted samples, in miniature schnauzers, and in patients with pancreatitis, diabetes, Cushing’s disease or hypothyroidism.
Cortisol—increases may be seen with Cushing’s disease (measured in different protocols including ACTH stimulation and Dexamethasone suppression tests); decreases may be seen with Addison’s disease.
T4 (thyroxine)—increases may indicate hyperthyroidism (primarily cats); decreases may indicate hypothyroidism (primarily dogs)
Complete Blood Count (CBC)
This is a common test performed on pets to provide objective information about the general health status of an animal. The objective data obtained from a CBC can be helpful in monitoring ill patients undergoing therapy; therefore, serial CBC requests are common.
Red Blood Cell (RBC) Parameters
RBC (red blood cell count), HCT (hematocrit) and HGB (hemoglobin)—increases in these parameters may support dehydration or a disease of increased production of RBCs; decreases indicate anemia and decreased oxygen-carrying capability of the blood.
MCV (mean cell volume)—increases indicate the presence of larger than normal cells, which may be related to young cells during response to an anemia; decreases indicate the presence of smaller than normal cells, which may be associated with chronic blood loss/iron deficiency.
MCH (mean cell hemoglobin) and MCHC (mean cell hemoglobin concentration)—increases suggest the presence of hemolysis or an interference in hemoglobin measurement; decreases suggest decreased hemoglobin concentration, which can be seen during response to anemia and chronic blood loss/iron deficiency.
RDW (red cell distribution width)—increases in this objective measure of variability of RBC size indicates increased variability in size that can aid the veterinarian in identifying the cause of an RBC problem.
RETIC (reticulocytes)—increases indicate growing numbers of immature RBCs, indicating a response to a peripheral demand for RBCs; decreases indicate few or no immature RBCs, indicating the body is unable to respond to a demand for RBCs (non-regenerative anemia)
White Blood Cell (WBC) Parameters
WBC (white blood cells)—increases may be due to inflammation, stress, excitement and leukemia; decreases may be due to overwhelming inflammation and bone marrow failure.
Leukocyte Differential—Various patterns of change in numbers of NEU (neutrophils), LYM (lymphocytes), MONO (monocytes), EOS (eosinophils), and BASO (basophils) may be seen with different types of inflammation, stress, excitement and leukemia
• NEU—inflammatory cell associated with infectious and noninfectious disease processes
• LYM—immune cell highly responsive to “stress” and potentially increased during chronic infection
• MONO—inflammatory cell associated with repair of tissue injury
• EOS—inflammatory cell associated with parasitic disease, hypersensitivity and allergy
• BASO—inflammatory cell associated with parasitic disease, hypersensitivity and allergy
Platelet (PLT) Parameters
PLT (platelet) and PCT (platelet crit)—increases in these parameters of overall platelet mass are potentially associated with hypercoagulable state; decreases may be seen with decreased production (bone marrow failure), increased consumption (coagulation, inflammation, etc.) and destruction in the blood (infectious, immune-mediated, etc.)
MPV (mean platelet volume)—increases indicate presence of larger than normal platelets commonly associated with response to need for platelets (not significant in cats)
PDW (platelet distribution width)—increases in this objective measure of variability of platelet size indicates increased variability in size which may be an indicator of response to a need for platelets (not significant in cats); decreases may be seen with immune-mediated thrombocytopenia.
A urinalysis is performed on a urine sample and provides insight into kidney functions as well as the hydration status of the animal. This valuable test may also be helpful in diagnosing and monitoring various diseases and metabolic disturbances throughout the body.
Specific Gravity—determined by the kidney’s ability to concentrate urine in response to the hydration status.
pH—reflects the acid-base status if the animal is well-hydrated
PRO (protein)—small amounts of protein may be normally found in urine, but larger amounts may indicate kidney disease.
GLU (glucose)—high levels are usually associated with an elevated blood glucose concentration.
KET (ketones)—elevated levels may indicate an increase in breakdown of lipids within the body.
UBG (urobilinogen)—abnormally high levels may indicate liver or hemolytic disease.
BIL (bilirubin)—abnormally high levels may indicate liver or hemolytic disease; in dogs (especially male dogs) bilirubinuria is common even under normal conditions; bilirubinuria in cats is significant.
RBCs and Hemoglobin—the test may be positive due to hematuria, hemoglobinuria or myoglobinuria; blood in the urine is often a sign of inflammation, infection and/or trauma.
WBCs—excessive numbers of WBC indicate inflammation somewhere in the urinary tract.
UPC (urine protein:creatinine ratio)—an important screening test for early kidney disease and to help monitor treatment of renal disease; increases may indicate significant protein loss through the kidneys.
Other Possible Tests
Canine/Feline Giardia—test for a protozoan parasite that may inhabit the small intestine of dogs, cats, humans and most domesticated animals, often causing diarrhea.
Canine Parvovirus—test for one of the most common, severe, and potentially fatal gastrointestinal diseases in young dogs.
Feline Immunodeficiency Virus (FIV) and Feline Leukemia Viruses (FeLV)— tests for two of the major causes of illness and death in cats
When can I expect results?
Many of the tests routinely recommended can be performed in-clinic, providing results quickly and allowing for prompt treatment for your pet. In-clinic blood testing also lets you be more involved in your pet’s care, since you can discuss test results with your veterinarian while you’re still at the clinic.
Normal results can rule out certain diseases right away, so you can worry less. If results are abnormal, your veterinarian can make fast decisions about next steps, including treatment and additional diagnostics. This saves you time and money and gives you answers that can help your pet immediately.
Other blood work and testing is sent out to a laboratory for analysis. Results for send-out labwork can be expected back in 1-7 business days.