HR lesson 4 Pathogenesis and evaluation of the thyroid gland

What does a TT4 measure?

Measures all the thyroxine in the blood, both unbound and bound.

What does fT4 measure?

Measures only unbound active thyroxine in the blood

What does TSH measure?

Regulates thyroid hormone production and aids in diagnosing thyroid disorders

What does TgAA measure?

Identifies antibodies against thyroglobulin for autoimmune thyroid disease.

If you have a low TT4 what does it suggest in canines?

Hypothyroidism

What is the first line of testing for hyperthyroidism in cats?

TT4

What thyroid test more accurately reflects thyroid function and is less affected by non-thyroidal illness in canines?

fT4

What thyroid test detects mild or early hyperthyroidism and is used along side TT4 for reliability in cats?

fT4

What thyroid test is usually elevated in primary hypothyroidism and is not a stand-alone test in canines?

TSH

What thyroid test can aid in the diagnosis of hyperthyroidism or iatrogenic hypothyroidism in cats?

TSH

What thyroid test indicates immune mediated lymphocytic thyroiditis?

TgAA

When is a low TT4 common in horses?

When they are stressed by disease or exercise

What diagnostic will show mild normocytic, normochromic, non-regenerative anemia during hypothyroidism?

CBC

What diagnostic will show hyperlipidemia due to increased triglycerides and hypercholesterolemia during hypothyroidism?

Chem

What is the Erythrocyte morphology during hypothyroidism?

Target cells (leptocytes)

When testing for hyperthyroidism what will the CBC show?

Stress leukogram, Heinz bodies, and increased Factor VIII

When testing for hyperthyroidism what will the Chem show?

• Increased ALT/ALP

• Decreased Cholesterol

• Increased glucose

• Decreased Fructosamine

What will the specific gravity of the urine during hyperthyroidism?

Decreased

What analytes are used to diagnose hypothyroidism in dogs?

TgAA, TT4, fT4