Hypothyroidism

Question 1

What are the clinical signs you might associate with hypothyroidism?

Answer 1

1. Weight gain
2. Heat seeking
3. Skin changes
4. Lethargy
5. Mental dullness
6. Exercise intolerance

Question 2

What type of skin changes would you associate with hypothyroidism?

Answer 2

1. Bilateral
2. Non-puritic
3. Scaling
4. Hyperkaratosis
5. Hyperpigmentation

Question 3

What would you see on CBC of hypothyroidism?

Answer 3

1. Normochromic
2. Normocytic
3. Non-regenerative anemia
4. TARGET CELLS (due to increased erythrocyte membrane cholesterol loading, associated with hypercholesterolemia)

Question 4

What 2 major changes would you see on biochem associated with hypothyroidism?

Answer 4

1. Hypercholesterolemia

2. Hypertriglyceridemia

Question 5

True or False: It is appropriate to correct all states of low thyroid concentration.

Answer 5

FALSE - it is inappropriate to correct states of low thyroid concentration due to non-thyroidal illnesses.

Question 6

What is the GOLD STANDARD for measuring fT4?

Answer 6

Equilibrium dialysis

Question 7

True or False: Equilibrium dialysis can distinguish animals with low TT4 due to NTI from those with hypothyroidism.

Answer 7

TRUE

Question 8

A dog with primary hypothyroidism would be expected to have an increased or decreased TSH level?

Answer 8

Increased

Question 9

In general, an elevated TSH is common or rare in euthyroid dogs?

Answer 9

RARE

Question 10

True or False: TSH is not highly specific for primary hypothyroidism.

Answer 10

FALSE - TSH is HIGHLY specific for primary hypothyroidism.

Question 11

True or False: TSH can be used alone as a screening test for hypothyroidism.

Answer 11

FALSE - TSH should NOT be used alone as a screening test.

Question 12

The presence of ____ seems to be the earliest known indicator of thyroid pathology.

Answer 12

TgAA (anti-thyroglobulin antibodies)

Question 13

True or False: It is appropriate to start thyroid supplementation with a low TT4.

Answer 13

FALSE - In order to start thyroid supplementation, there must be clinical signs consistent with hypothyroidism.

Question 14

Which two drugs have the ability to induce true hypothyroidism?

Answer 14

1. Sulfa antimicrobials

2. Phenobarbital

Question 15

True or False: Hypothyroidism is overdiagnosed.

Answer 15

TRUE

Question 16

What is the drug used to treat hypothyroidism?

Answer 16

Levothyroxine

Question 17

What is the dosage for Levothyroxine?

Answer 17

0.02 mg/kg every 12 hours

Question 18

To monitor a patient’s response to treatment with Levothyroxine, you should evaluate the dog after ___-___ weeks of supplementation.

Answer 18

6-8 weeks

Question 19

True or False: Not all clinical signs of hypothyroidism are reversible.

Answer 19

FALSE - with treatment, ALL clinical signs of hypothyroidism are reversible.

Question 20

When monitoring response to treatment, measure ___ and ___ 4-6 hours after administration of Levothyroxine.

Answer 20

1. T4

2. TSH

Question 21

If autoantibodies are present at 4-6 hours after administration, you cannot monitor with ___. You then need to use ___.

Answer 21

You cannot monitor with T4. You then need to use fT4ED.

Question 22

Post-dose (Levothyroxine) T4 should be increased, decreased, or within the reference interval?

Answer 22

In the upper half or above the reference interval

Question 23

Post-dose (Levothyroxine) TSH should be increased, decreased, or within the reference interval?

Answer 23

Within the reference interval

Question 24

The Levothyroxine dose should be reduced if the post-dose T4 is > ____.

Answer 24

> 6 ug/dL

Question 25

What is the life expectancy of an adult dog with primary hypothyroidism?

Answer 25

Normal