Simplifying Lab Tests: Interview with Veterinary Diagnostician Dr. Jean Dodds
Diagnostic lab test results are intimidating.
With rows and rows of acronyms like CBC (complete blood count) and WBC (white blood cells) it can be downright impossible for non-medically trained pet owners to decipher what’s going on.
But since lab work is an important part of keeping pets healthy, learning more about them can put pet owners in a better place the next time tests are taken. To help break things down, we enlisted the help of Dr. Jean Dodds, holistic veterinarian, veterinary diagnostician and owner/founder of Hemopet Blood Bank and Hemolife Diagnostics in Garden Grove, California.
The Honest Kitchen: What is the importance of regular laboratory testing for cats and dogs?
Jean Dodds: Laboratory screening should always be part of an annual wellness exam in healthy dogs and cats starting around puberty. As pets age, this becomes even more important, because published studies have shown that even without overt clinical issues, significant body dysfunction was identified in 20 percent of older dogs and 17 percent of older cats.
THK: Which tests do you recommend?
JD: Lab profiles should include CBC, comprehensive serum chemistries and a thyroid profile—not just a total T4—plus urinalysis.
THK: What illnesses or signs of health can these tests reveal?
JD: Disease development can be subclinical at first and then progress to overt symptoms, if not detected sooner. Results of physical examination and a thorough medical and family history may all be normal, or, can reveal reasons for a pet’s malaise, poor appetite, irritability, vocalizing, eating and drinking more or less, poor grooming or social behavior, and a change in normal pattern.
THK:For many of us, lab test results are like a foreign language. What are common “problem areas” to look out for in testing for cats and dogs?
JD: Lab results for the CBC may determine if there is anemia and whether it is regenerative, infection or inflammation and risk of bleeding excessively (low platelet count). The serum chemistry profile assesses liver, kidney, pancreatic, and adrenal function and protein and electrolyte levels. Urinalysis looks at kidney and bladder function, presence of excess protein, glucose and pH, crystals, infection or stones formation.
Lab values for young animals are often different to the normal ranges for adults and geriatrics—e.g. higher lymphocyte counts, higher phosphorus and ALK P, lower total protein. Lab values for certain breeds differ—e.g. higher potassium in Japanese breeds, lower basal thyroid levels in sighthounds, lower platelet counts and large platelets in Cavaliers. Calcium levels in dogs, but not cats, are affected by the amount of serum albumin present, so calculation of a true “corrected calcium” reading may be needed.
Blood Test Acronyms and Words Deciphered
Following are some excerpts from “Laboratory Tests—Understanding Your Pet’s Blood Work,” a guide written by Dr. Jean Dodds for Antech Diagnostics.
Alanine aminotransferase (ALT, SGPT) is an indicator of active liver damage but does not indicate the underlying cause.
Albumen (ALB) is serum protein that helps evaluate hydration, hemorrhage, and intestinal, liver, and kidney disease.
Alkaline phosphatase (ALKP) elevations may indicate liver damage, Cushing’s disease, active bone growth in young pets. This test is especially significant in cats as even slight elevations are indicative of liver disease.
Amylase (AMYL) elevations show pancreatitis or kidney disease.
Aspartate aminotransferase (AST, SGOT) increases may indicate liver, heart, or skeletal muscle damage.
Bile acids test evaluates liver function-congenital liver shunts, cirrhosis, active liver disease.”
Bilirubin elevations may indicate liver, gall bladder, or hemolytic diseases.
Blood urea nitrogen (BUN) indicates kidney function. An increased blood level is called azotemia and may be caused by kidney, liver, heart disease, urethral obstruction, shock, dehydration, or an intestinal or stomach foreign body. A low BUN may indicate a cirrhotic liver or portal shunt.
Calcium (CA) deviations may indicate a variety of diseases. Tumors, hyperparathyroidism, kidney disease, anal gland tumor, are just a few of the diseases that alter calcium levels.
Chloride (CL) is an electrolyte often lost with vomiting and Addison’s disease. Elevations may indicate dehydration.
Cholesterol (CHOL) is used to supplement diagnosis of hypothyroidism, liver disease, Cushing’s disease, and diabetes mellitus.
Cortisol is a hormone measuring tests for Cushing’s disease (low dose dexamethasone suppression test, high dose dexamethasone suppression, urine cortisol-creatinine) and Addison’s disease (ACTH stimulation test).
Creatinine reveals kidney function. This test helps distinguish between kidney and non-kidney causes of elevated BUN.
Eosinophils are specific types of white blood cells that may indicate allergic or parasitic conditions.
Gamma glutamyl transferase (GGPT) is an enzyme that indicates liver disease or corticosteroid excess.
Globulin is a blood protein that often increases with chronic inflammation and certain diseases such as FIP.
Glucose is a blood sugar. Elevated levels may indicate diabetes mellitus (cats/dogs). Low levels can cause collapse, seizures, or coma.
Granulocytes and lymphocytes/monocytes are specific types of white blood cells.
Hematocrit (HCT, PCV) measures the percentage of red blood cells to detect anemia and dehydration.
Hemoglobin and mean corpuscular hemoglobin concentration are the oxygen-carrying pigments of red blood cells.
Lipase is an enzyme that may indicate pancreatitis.
Phosphorus (Phos) elevations are often associated with kidney disease, hyperthyroidism, and bleeding disorders.
Platelet counts measure cells that form blood clots.
Potassium (K) is an electrolyte lost with vomiting, diarrhea, or excessive urination. Increased levels may indicate kidney failure, Addison’s disease, dehydration, and urethral obstruction. High levels can lead to cardiac arrest. Low levels may occur with loss of appetite, especially in cats.
Reticulocyte are immature red blood cell. High levels indicate regenerative anemia.
Sodium (Na) is an electrolyte lost with vomiting, diarrhea, and kidney and Addison’s disease. This test helps indicate hydration status.
Thyroid tests (T4, Free T4, TSH)—Decreased levels signal hypothyroidism, while high levels indicate hyperthyroidism in cats.
TLI, B12, folate are intestinal tests to indicate malfunction of the digestive tract of cats and dogs.
Total protein indicates hydration status and provides additional information about the liver, intestine, kidney, and infection.
White blood cells (WBC) measures the body’s immune cells. Increases or decreases indicate certain diseases or infections.
1-protcasc inhibitor (a1-PI) is a single sample of feces has been shown to be a reliable method to detect protein-losing enteropathy in human and pet patients.