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Have a young, healthy pet that doesn't seem to need testing? Consider testing now to establish a baseline to measure changes in your pet's health. |
Big Sky Pet Center offers a broad range of in-house diagnostics, including comprehensive blood testing. The following is a list of tests, values, and health indications.
Tests VetScan Comprehensive Diagnostic Profile Alanine aminotransferase: Albumin: Alkaline phosphatase: Amylase: Calcium: Creatinine: Globulin: Glucose: Phosphorus: Potassium: Sodium: Total bilirubin: Total protein: Blood Urea Nitrogen:
Alanine Aminotransferase: Alkaline Phosphatase: Creatinine: Glucose: Total Protein: Blood Urea Nitrogen:
Increased T4 • T4 concentrations tend to be higher in dogs less than one year old and decrease as the dog ages. • An increased T4 level in a feline is a reliable indicator of hyperthyroidism. Hyperthyroidism is the most common cause of elevated T4 and is one of the most frequently diagnosed diseases in small animals. The typical cause of spontaneous hyperthyroidism in cats is functional thyroid adenoma. Hyperthyroidism is rarely observed in dogs but, when seen, is usually indicative of neoplasia or the administration of too much sodium levothyroxine to a hypothyroid dog. Approximately 66% of the canine neoplasmas are adenocarcinomas. • Feline thyroid testing is usually conducted to diagnose hyperthyroidism, to monitor the effects of antithyroid treatment, or to monitor thyroid replacement treatment following destruction of neoplastic thyroid glands. When evaluating total T4 in cats, considerations must be allowed for age and concurrent diseases. T4 values are higher in younger cats and normally decrease with age. In older cats with suspected hyperthyroidism, concurrent diseases such as renal failure cause a condition known as euthyroid sick syndrome that may depress total T4 values. In these cases a free T4 by equilibrium dialysis test (fT4ED) is used to confirm a diagnosis of hyperthyroidism. • Three common conditions require confirmation with the fT4ED test. High normal T4 values (3-5 mg/dL) in a young cat without marked weight loss is normal. High values (>5 mg/dL) in an old cat showing signs of weight loss is usually diagnostic for hyperthyroidism. High normal values (3-5 mg/dL) in an old cat may indicate hyperthyroidism. Since these values can be suppressed by concurrent disease, a test for active hormone (fT4ED) is necessary to diagnose this occult hyperthyroidism. Decreased T4 • In dogs, the total T4 can be used to rule out a diagnosis of hypothyroidism. If total T4 is within the normal range it is highly unlikely that the dog is hypothyroid. A low or low-normal T4 value may be suggestive of but does not confirm hypothyroidism because non-thyroidal factors such as drugs and illness affect T4. A diagnosis of hypothyroidism in dogs can be confirmed with a free T4 by equilibrium dialysis (fT4ED). • Other causes of decreased T4 levels may be associated with drug therapy and euthyroid sick syndrome. The glucocorticoids are the most clinically relevant of the drugs affecting T4 levels. In euthyroid sick syndrome, decreased T4 levels are seen with such nonthyroidal illnesses as acute and chronic renal failure, diabetes mellitus, hepatic insufficiency and obesity. • After eliminating drug therapy and euthyroid sick syndrome, the most common cause of decreased T4 levels is primary hypothyroidism. Hypothyroidism in dogs is most often a result of lymphocytic thyroiditis or idiopathic atrophy. Thyroid tumors that have destroyed >75% of the thyroid gland may cause clinical signs of hypothyroidism. Congenital defects of the pituitary gland, pituitary destruction and pituitary suppression can cause secondary hypothyroidism in dogs. • Spontaneous hypothyroidism is rarely reported in cats. The common causes of feline hypothyroidism are bilateral thyroidectomy and overdoses of radioactive iodine or anti-thyroid drugs in hyper thyroid cats • Hypothyroid patients may also have elevated cholesterol concentrations. • To obtain an accurate basal T4 concentration, medications should be withheld from the patient for several days.
Hypercholesterolemia • A high fat diet or a blood sample collected shortly after the patient has eaten may cause hypercholesterolemia. Hypercholesterolemia is not apparent upon visual examination of the sample since it does not cause lipemia. • A reduction in thyroid activity causes a decrease in the catabolism of cholesterol, resulting in elevated cholesterol levels. Observing a high cholesterol level on a screening profile may be the first indicator of hypothyroidism. Cholesterol, when used in conjunction with free T4 levels, is a good indicator of canine hypothyroidism. • A preliminary diagnosis of hyperlipidermia may be made using cholesterol levels and the lipemic index printed on the VetScan result card. Cholesterol concentrations > 300 mg/dL in conjunction with a 2+ or 3+ lipemic index can indicate hyperlipidemia in fasted dogs. Feline hyperlipidemia may be diagnosed when a cholesterol concentrations >200 mg/dL and an index of 1+ or greater is observed in fasted cats. • Low levels of cholesterol are not usually a problem. Hypocholesterolemia has been observed with protein-losing enteropathy, some liver diseases, certain malignancies, and severe malnutrition. alanine aminotransferse (ALT), albumin, alkaline phosphatase (ALP), globulin, total bilirubin and total protein test results should be examined if liver disease is suspected. Low levels of protein, albumin and globulin can be observed in cases of protein-losing enteropathies and malnutrition.
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