Hypothyroidism

Question 1

Hypothyroidism

Answer 1

↓ production of T4 and T3
Primary most common
Also caused by idiopathic thyroid atrophy and lymphocytic thyroiditis

Question 2

Signalment of hypothyroidism

Answer 2

Labs and dobermans
Middle-aged Salukis (lymphocytic thyroiditis)

Question 3

CS of hypothyroidism

Answer 3

Depression, leth, Chr derm, hyperpig
Poor wound healing, KCS, uveitis
Weight redistribution, alopecia, bradycardia
Myxedema, etc.

Question 3

Lab findings associated with hypothyroidism

Answer 3

N/N non regenerative anemia
Fasting hypercholesterolemia
Hypertriglyceridemia

Question 4

Thyroid levels

Answer 4

Total T4 low
Free T4 low
TSH high

Question 5

Why is it important to make an accurate dx prior to therapy?

Answer 5

Greyhounds and other sight-hounds have natural lower T4 and Free T4 and TSH will be normal

Question 6

Euthyroid sick

Answer 6

Concurrent illness
Cortisol (cushings) will ↑ T4
Meds alter: glucos, sulfa-drugs, phenobarb

Question 7

Thyroiditis

Answer 7

Anti-thyroglobulin abs
Thyroid hormone auto-abs: anti-T4 and anti-T3 (cross react with Free T4 molecules in radioimmunoassays)

Question 8

Tx of hypothyroidism

Answer 8

Levothyroxine (max dose 0.8 mg BID)
Thyro-tabs canine
Liquid levo

Question 9

Monitoring for hypothyroidism

Answer 9

Give meds 1m
Serum Total T4
4-6hr after morning dose
Titrate dose low to mid-range level

Question 10

Myxedema coma

Answer 10

Emergency!
Hypotensive, bradycardic, hypothermic, stuporous

Question 11

How to tx myxedema coma

Answer 11

Correct abnormalities and support
IV levothyroxine