Diagnostic Tests

What is "fecal occult blood"?
"Fecal occult blood" refers to the presence of small quantities of blood in the stool that cannot be seen with the naked eye ("occult" means "concealed from view"). The blood can come from anywhere in the digestive tract, including the mouth, stomach, intestines or rectum.

What is coagulation?
Coagulation is the series of events that result in the formation of a clot.  In the body, coagulation occurs after any injury to a blood vessel or tissue, in order to stop bleeding.
Coagulation involves the interaction of blood vessel lining cells (endothelial cells), specialized blood cells called platelets that form a plug in the region of the damaged blood vessel, and circulating coagulation factors.

What is a Complete Blood Count?
The Complete Blood Count, usually just called a CBC, is one of the most basic blood tests your veterinarian can request, and yet it is one of the most important tests for determining the health status of a dog. It includes a series of measurements that describe the quantity and quality of the cellular elements in the blood.

What is cytology?
Cytology is the microscopic examination of cells that have been collected from the body. By examining the appearance of these cells, including their number, size, shape, color, internal characteristics, and how they fit together with their neighbors, it is often possible to make a diagnosis.

What is cytology?
Cytology is the microscopic examination of cells that have been collected from the body.  By examining the appearance of these cells, including their number, size, shape, color, internal characteristics, and how they fit together with their neighbors, it is often possible to make a diagnosis.

What are electrolytes?
Electrolytes are the salts and metallic components of serum (serum is the liquid portion of blood). Electrolytes are dissolved within serum and carry an electrical charge, either negative or positive. The negatively charged electrolytes are balanced by the positively charged electrolytes.

What is a urine protein:creatinine ratio?
The urine protein:creatinine ratio is a simple test that measures how much protein is being lost through the kidneys, and determines if the loss poses a health risk for the dog. The test involves measuring the amount of protein and creatinine in a urine sample, and mathematically dividing the protein value by the creatin

What is the urine cortisol/creatinine ratio?
Cortisol is a stress hormone that is excreted from the body in the urine.  The amount of cortisol in the urine reflects the average cortisol concentration in the blood at the time that the urine was formed. However, this measurement is affected by the concentration of the urine.   Creatinine is a product of muscle metabolism and it is normally lost in the urine at a relatively steady rate. Because of this, the ratio of cortisol to creatinine in the urine can be used to account for the effect of urine concentration.

What is ethylene glycol?
Ethylene glycol is the most common and the most dangerous form of antifreeze. Ethylene glycol can also be found in some film processing solutions.

What is a Coombs’ test?
A Coombs’ (or direct antiglobulin) test detects the presence of immunoglobulins (antibodies) on the surface of red blood cells. Immunoglobulins are proteins made by white blood cells (specifically plasma cells). The Coombs’ test detects these immunoglobulins using specific antiserum that reacts against different types of immunoglobulins. If this antiserum detects immunoglobulins on the surface of the red blood cells, it will cause the red blood cells to agglutinate or clump in the test tube. This test is performed at a veterinary reference laboratory and requires a single blood sample.

What is cytology?
Cytology is the microscopic examination of cells that have been collected from the body.  By examining the appearance of these cells, including their number, size, shape, color, internal characteristics, and how they fit together with their neighbors, it is often possible to make a diagnosis

What is the dexamethasone suppression test used for?
There are two tests that use dexamethasone (a synthetic cortisol) for diagnosing Cushing’s Disease or Cushing’s Syndrome-- a "LOW DOSE" and a "HIGH DOSE" test. The low dose dexamethasone suppression test can be used to screen for the presence of hyperadrenocorticism (Cushing’s disease) and in many cases it will differentiate the type of Cushing’s disease that is present. The high dose dexamethasone test is used when the patient has been confirmed with Cushing’s disease by means of the low dose test, but is one of the cases in which the low dose test has not clearly differentiated the type of Cushing’s disease that is present.  Both the low dose and the high dose dexamethasone suppression tests take 8 hours to complete and involve three blood samples. The first sample is taken prior to the injection of dexamethasone, and the second and third samples are taken at 4 and 8 hours following the dexamethasone injection. The difference between the two tests is in the amount of dexamethasone that is injected.  The two tests must be run on different days.

What is DNA?
Sometimes called the "blue print of life", DNA is a complex molecule that carries the genetic code of an organism. All common forms of life, such as viruses, bacteria, plants, and animals carry a complete copy of their own DNA in each of their cells. Many related organisms have similar DNA, but there are small differences in the DNA sequence that are unique to each organism.

What is microalbuminuria?
Albumin is an important protein that is found in blood, but is not normally present in the urine of healthy dogs. Microalbuminuria refers to the presence of small amounts of albumin in urine ("micro" = small amount, "uria" = present in urine). Finding small amounts of albumin in the urine may indicate underlying health problems, and may be an early warning signal of renal (or kidney) damage or disease.

What is ACTH?
ACTH (adrenocorticotropic hormone) is a hormone produced by the pituitary gland.
The term endogenous simply refers to the ACTH that is produced by the dog itself (as opposed to synthetic ACTH which is used for diagnostic testing purposes).

What is a fecal Baermann test?
A fecal Baermann is a specialized test for detecting certain types of parasites or "worms" in stool material. Many parasites pass their eggs in the host’s stool, and infection is easily diagnosed by examining the stool for the presence of parasite eggs. [link to Fecal Flotation] However, some parasites pass larvae instead of eggs; larvae cannot be detected by routine stool examination, and a special technique called a fecal Baermann is required to find them.

What is a fecal flotation?
Fecal flotation is a routine veterinary test that is used to identify the presence of intestinal parasites or "worms". The test actually detects the eggs of mature parasites that live in the intestine and pass their eggs to the outside in the host’s stool. Some of the parasites are worm-like, while others are simple single-celled organisms called protozoa.

What is hypercalcemia?
Hypercalcemia means that the level of calcium in the blood is abnormally high. (hyper =  above or excessive; -emia = blood)

Dogs that have been diagnosed with epilepsy are usually prescribed one or more medications to prevent convulsions or seizures. These medicines, called anticonvulsants, are often needed for long periods of time, and in many cases are used for the life of the dog. Careful monitoring of these epileptic dogs is necessary, first of all to make sure the medicine is being effective, and also to ensure there are no problems caused by the long term use of the medication

Why is it important to prepare my dog for blood collection?
Having your dog properly prepared before blood collection helps to ensure that test results are as accurate and reliable as they can be. Sometimes abnormal test results say more about how the dog was prepared than about true illness. Having confidence in the results avoids unnecessary worry, and eliminates the need for repeat testing to verify the results.

Is there a blood test to detect pregnancy in the bitch?
A blood test is now available that detects pregnancy in the bitch by measuring levels of a hormone called relaxin. This hormone is produced by the developing placenta following implantation of the embryo, and can be detected in the blood in most bitches as early as 22-27 days post breeding.  The level of relaxin remains elevated throughout gestation, and declines rapidly following the end of the pregnancy.

With modern drugs and sophisticated equipment, the risk associated with general anesthesia and surgery is minimal for the healthy dog. However, the potential for complications still exists, and the best way to decrease the risk for your dog is to have a complete pre-surgical evaluation performed before the procedure. This allows the veterinarian to determine if your dog has any underlying problems that might lead to complications, and to make any adjustments necessary to safeguard your dog’s health and comfort.

Why is finding protein in urine a cause for concern?
Protein is used throughout the body in a variety of ways, and is especially important for growth and repair. Maintaining adequate levels of protein is critical for the long-term health of a dog, and any persistent loss of protein in the urine represents a waste of a precious resource that is difficult to replace.

What is serum biochemistry?
Serum biochemistry refers to the chemical analysis of serum, which is a major component of blood. The analysis can include many different tests, each of which provides information about one or more organs in the body.   If a test result is abnormal, it may indicate that disease is present. Further assessment of the test results may indicate which organ system is affected, and may provide information about the nature and severity of the problem.

When is serum iron testing indicated?
Serum iron tests are indicated when the results from a complete blood count (CBC) indicate that your pet is anemic (decreased red blood cell numbers and decreased hemoglobin) and that the red blood cells are microcytic (smaller than usual) and hypochromic (contain less hemoglobin than usual).

What are serum proteins?
Serum is the liquid portion of blood from which the red blood cells, white blood cells, and factors involved in blood clotting have been removed.

Canine Diabetes: An Overview
It is not uncommon for dog's to be born with or develop diabetes. Canine diabetes (also known as Canine Diabetes mellitus or sugar diabetes) results from a deficiency of - or decreased response to - insulin. The pancreas produces insulin, which helps body tissues process glucose (sugar). Without insulin or with a decreased response to insulin, blood glucose levels rise, resulting in hyperglycemia, while the dog's body tissues remain starved for glucose. The elevated blood glucose eventually passes into the urine, creating a condition called glycosuria. As the disease progresses, metabolism changes cause ketosis, a condition in which chemicals called ketones accumulate in the blood and body tissues.

What is Addison’s Disease?
Addison’s disease (or hypoadrenocorticism) is caused by a decreased production of two hormones from the adrenal gland. These hormones are cortisol (a stress hormone) and aldosterone (a mineralocorticoid hormone that regulates the body’s water balance through its effects on sodium and potassium).

What is Cushing’s disease?
Cushing’s disease is a condition caused by an increased production of the stress hormone cortisol by the adrenal glands. Increased cortisol production may be related to:

• excessive stimulation of the adrenal glands by the pituitary gland, usually as a consequence of a pituitary tumour (pituitary origin)
• the unregulated production of cortisol by the adrenal glands (adrenal origin)
• occasionally, administration of steroid-containing medications may result in the development of Cushing’s disease (iatrogenic origin)

What are the causes of increased thirst and urination?
These clinical signs are non-specific and can be caused by many different diseases or conditions. Usually it is the production of excess, dilute urine that results in a compensatory increase in water consumption, but occasionally the condition is one of increased water intake resulting in the production of large volumes of dilute urine.

What tests are suggested for the diagnosis of liver disease?
Generally the following screening tests are recommended when liver disease is suspected: a complete blood count (CBC), a serum biochemical profile, and a urinalysis.

What is the pancreas?
The pancreas is a glandular organ located close to the liver, the stomach, and the small intestine. It functions in the control of blood glucose (sugar) through the secretion of insulin and glucagon hormones, and aids in digestion through the secretion of lipase and amylase enzymes.

What might be the cause of abdominal enlargement?
The causes of abdominal enlargement include an increase in intra-abdominal fat due to simple overall weight gain as a result of excess calories or insufficient exercise. A redistribution of fat into the abdominal cavity may occur with Cushing's disease. Dogs suffering from hypothyroidism often gain weight, as do some dogs with insulinomas (tumors of the insulin producing cells of the pancreas). This weight gain may be perceived as abdominal enlargement.

What might be the cause of seizures in my dog?
There are numerous possible causes of seizures. These causes can be grouped into metabolic causes such as liver and kidney disease, into diseases or conditions resulting in hypoglycemia (reduced blood sugar concentrations) or hypocalcemia (reduced blood calcium concentration), and into diseases directly involving the central nervous system (CNS) including inflammation, infection, and tumors of the CNS. Toxins, trauma, and infectious conditions may also result in seizure activity. Occasionally seizures may be idiopathic (of unknown cause).

What might be causing my dog to lose weight?
Weight loss may be caused by physical problems in grasping, chewing, and swallowing food. It may be related to problems of inadequate nutrition because of increased energy requirements; for example due to rapid growth, increased levels of exercise, pregnancy, or lactation (nursing). A poor quality diet may result in weight loss. And finally, underlying medical conditions such as Addison’s disease in dogs, disease in the kidney, heart, liver or intestines, or cancer, may cause significant weight loss.

What is pallor?
By definition, pallor means paleness or absence of skin coloration. Because our dogs are covered with a thick hair coat, we usually cannot appreciate pale skin, but pallor may be seen on mucous membranes such as the gums or eyelids, or on the skin of the ears.

What may be causing my dog to be weak?
Weakness is a non-specific symptom that can be caused by many different diseases or conditions. Problems with the cardiovascular system are an important cause of weakness or fainting spells (called syncope) because of poor circulation or irregular heart rate or rhythm. Severe anemia from any cause will also cause lethargy or weakness. Severe hypoglycemia (low blood sugar), hypothyroidism, marked increases or decreases in serum potassium concentrations (termed hyperkalemia and hypokalemia, respectively), and neoplasia (cancer) are common causes of weakness. Spinal cord disease such as disc disease, may also present as weakness, usually of the hind limbs.  Musculoskeletal diseases such as arthritis may cause an apparent weakness.

What are the causes of nasal discharge and sneezing?
Although these two clinical signs may not always appear together, both are associated with disorders affecting the nasal cavity and/or nasal sinuses.
While occasional sneezing is perfectly normal, repeated bouts of vigorous sneezing may indicate irritation of the nasal cavity caused by foreign bodies, viruses, air-borne irritants or rarely, nasal mites.

My dog is urinating on the floor! What might be causing my dog to lose his house-training?
The causes of inappropriate urination include diseases (infections, tumors) affecting the kidneys, bladder and genital tract, endocrine diseases such as diabetes mellitus, diabetes insipidus, Cushing’s disease and estrogen responsive urinary incontinence, as well as neurological disease and behavioral problems. Some drugs such as prednisone may cause your dog to drink more, causing increased urine production, which may result in ’accidents’ in the house.

What are the causes of vomiting?
Vomiting is a non-specific symptom of many different diseases and conditions. The frequency and type of material that is vomited along with a history and other clinical signs that your dog is exhibiting may give us clues as to its cause. If, for example, a dog has recently ’raided’ the garbage and subsequently begins to vomit, it is likely that he is experiencing a simple bout of ’dietary indiscretion’. However in many cases, the underlying cause is not so clear.

What are the causes of diarrhea?
Many different diseases and conditions may result in diarrhea. The frequency, urgency, and physical characteristics of the diarrhea, along with a history and other clinical signs that your dog is exhibiting may provide some clues to its cause.

What could be causing my dog to cough?
A number of different conditions may cause coughing episodes. Some of these conditions include inflammation and infection (bacterial, fungal, and viral) of the respiratory tract, foreign bodies or tumors within the respiratory tract, allergies, tracheal collapse, parasitic disease (including heartworm infections and lungworm infections), aspiration pneumonia, and underlying heart disease.

What does fever of unknown origin mean?
This is a term that is generally used to refer to a persistent fever of greater than 39.7 °C, for which the underlying cause is not readily evident.

What might be causing low blood sugar in my dog?
There are several conditions that may cause hypoglycemia (low blood sugar also known as low blood glucose), some of which are more serious than others.  Severe liver disease, hypoadrenocorticism (Addison’s disease), severe bacterial infection (sepsis), inadequate nutrition in toy breed puppies, and some types of tumors may all cause this abnormality.  One of the more common tumors to cause hypoglycemia is a specific tumor of the pancreas, called an islet cell tumor or insulinoma, which produces excessive levels of insulin, thus lowering the blood sugar level.  Other tumors that may result in hypoglycemia include tumors of the liver and smooth muscle.

What could be the cause of bleeding?
One of most common and obvious causes of bleeding (hemorrhage) is trauma. In most instances the bleeding will be self-limiting (stop on its own) unless the wound is severe. Occasionally bleeding may occur from sites such as the nose, mucous membranes, or urinary tract, but no incidence of trauma has occurred. Or perhaps 'pin point' hemorrhages are found on the gums or skin (these are called petechiae). These more troublesome clinical signs may be associated with problems related to blood coagulation factors, platelets, platelet function, or some other underlying disease.

What is the thyroid gland?
The thyroid gland is found near the trachea (windpipe), just below the larynx (voice box). It is a paired gland that is responsible for the production of thyroid hormones. The major thyroid hormone that is produced by the thyroid gland is thyroxine (T4). A small amount of another thyroid hormone, triiodothyronine (T3), is also made by the thyroid gland. Thyroid hormones have far-reaching effects on the body, in essence governing the body’s metabolic rate.

What is trypsin-like immunoreactivity?
Trypsinogen is a proenzyme (a non-activated enzyme) that is secreted into the small intestine by the pancreas, along with other pancreatic digestive enzymes. When it reaches the small intestine, trypsinogen is converted to trypsin, an enzyme that is involved in the digestion of proteins. In healthy animals, a small amount of trypsinogen escapes from the pancreas into the blood circulation, and can be measured in a blood sample by a test called trypsin-like immunoreactivity.

What is a urinalysis?
Urinalysis is a simple test that assesses the physical and chemical composition of urine. Abnormal results usually indicate that there is a disorder affecting the kidneys and/or urinary system. However, a urinalysis can also provide clues about problems in other organ systems, or may indicate the presence of a metabolic disease, such as diabetes mellitus. Urinalysis is necessary for a complete assessment of the kidneys and urinary system, and should be included in any thorough evaluation of a dog’s health status.

What is von Willebrand’s disease?
Von Willebrand’s Disease is one of the most common hereditary bleeding disorders in dogs, and has been identified in more than 50 different breeds. Breeds with an increased incidence of von Willebrand’s disease include the Doberman Pinscher, Manchester Terrier, Pembroke Welsh Corgi, French Poodle, Shetland Sheepdog (or Sheltie), and Scottish Terrier.

What is wellness testing?
Wellness testing is the term given to a group of tests that is performed specifically to detect signs of early disease in a dog that is apparently healthy.

Your dog has been scheduled for an endoscopic examination. The purpose of this procedure is to make a diagnosis of the disease that has been causing your pet’s clinical signs of vomiting or diarrhea.

When any irregular heart rhythm is detected on clinical examination, an electrocardiogram (ECG or EKG) should be performed. The small electrical impulses normally generated by the heart are amplified 3,000 or more times and recorded by the ECG machine. An ECG can detect minor disturbances in the heart beat or rhythm and allow your veterinarian to diagnose many types of heart disease.

I have been told I can have my female dog scanned to see if she is pregnant. What does this involve?
An ultrasound examination, also known as ultrasonography or echosonography, is an imaging technique that allows internal body structures to be seen by recording echoes of ultrasonic waves. Unlike x-rays, which are potentially dangerous, ultrasound waves are considered to be entirely safe.

What is the purpose of the bile acid test?
The bile acid test is performed to determine if the liver is able to do its job. In order to function properly, the liver must have enough healthy cells to do the job, and a good blood supply. If the liver has enough healthy cells, it is described as having "adequate functional mass". The bile acid test is based on the principle that a healthy liver, with adequate functional mass and a good blood supply, can “recycle” bile acids, while a damaged or defective liver cannot.

Why is bone marrow collected and examined?
The bone marrow produces most of the cellular elements that are found in blood. If abnormalities are found in a patient’s blood sample, examination of the bone marrow may help to determine the cause of the problem.

What are antibodies?
Antibodies are specialized proteins, also called immunoglobulins, that are primarily found in the bloodstream. They are produced by specialized white blood cells called plasma cells, a form of lymphocyte. Specific antibodies are generated in response to the different foreign substances (for example bacteria, viruses, toxins) that the body encounters, and provide varying lengths of immunity against these substances.

Ask purebred fanciers why they prefer known breeds to mixed-breeds and they’ll tell you it has a lot to do with predictability: with mutts, they say, you never know exactly what you’re getting, but with specific AKC-recognized breeds, you know precisely what to expect in terms of behavior, temperament, and looks.