Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Small Animal Medicine > Endocrinology - Hypothyroidism > Flashcards

Endocrinology - Hypothyroidism Flashcards

1
Q

What does TBG stand for?

A

thyroid hormone binding globulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does TSH stand for?

A

thyroid stimulating hormone - thyrotropin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does TRH stand for?

A

Thyrotropin releasing hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does T4 stand for?

A

Thyroxine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does TgAA stand for?

A

Thyroglobulin antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does T4AA stand for?

A

T4 autoantibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does NTI stand for?

A

non-thyroidal illness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does ED stand for? (in relation to the thyroid not male pee pee issues)

A

equilibirum dialysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does RIA stand for?

A

radioimmunoassay

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The thyroid hormone has a lot of functions. It is important to keep in mind that ___ ______ ______ escapes the adverse effects of excess or insufficiency.

A

No organ system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the major secreted thyroid hormone?

A

T4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the major biologically active thyroid hormone?

A

T3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Is T3 or T4 more potent?

A

T3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What form of hormone, bound or unbound, is biologically active and able to mediate regulatory feedback?

A

The unbound (free) form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 2 major categories of primary hypothyroidism?

A

Lymphocytic thyroiditis or idiopathic thyroid degeneration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is lymphocytic thyroiditis?

A

Lymphocytic infiltration with progressive destruction of thyroid follicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How can inflammation in cases of lymphocytic thyroiditis be measureD?

A

In the serum by measuring antibodies to thyroid components - usually thyroglobulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

True or False: You will see clinical signs well before extensive damage by lymphocytic thyroiditis occurs.

A

False - extensive destruction occurs before clinical signs of hypothyroidism develops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is idiopathic thyroid degeneration?

A

Loss of thyroid parenchyma and then replaced by adipose and fibrous tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What breeds are over represented by hypothyroidism?

A

Doberman, golden retriever, labrador retriever, and cocker spaniel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

When do clinical signs due to hypothyroidism typically develop?

A

in middle aged animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What general clinical signs are associated with hypothyroidism?

A

Decreased metabolic rate, skin/haircoat changes (most common), neurologic, ocular, and myxedema coma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What clinical signs are associated with decreased metabolic rate?

A

lethargy, dullness, weight gain without polyphagia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What skin/haircoat changes are associated with hypothyroidism?

A

Alopecia, hyperpigmentation, and pyoderma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What neurologic clinical signs are associated with hypothyroidism?
Peripheral neuropathy, central vestibular disease, subclinical myopathy, and less commonly (seizures, laryngeal paralysis, megaesophagus, MG, and others)
26
What ocular clinical signs are associated with hypothyroidism?
corneal lipid
27
What is a myxedema coma?
life-threatening hypothermia, bradyarrhythmias, and rapid deterioration in the mental state
28
What clinical pathology is associated with hypothyroidism?
Normocytic, normochromic, non-regenerative anemia (30% of dogs), hypercholesterolemia (75% of dogs), hypertriglyceridemia, and a normal UA
29
What thyroid screening test is used to rule out hypothyroidism?
Total thyroxine (TT4)
30
What forms of T4 does TT4 screen for?
bound and unbound
31
True or False: A TT4 can diagnose hypothyroidism.
False - you should never use a low T4 in isolation to diagnose hypothyroidism
32
Why is as TT4 screen helpful in ruling out hypothyroidism?
Because very few true hypothyroid dogs will have a normal T4
33
What can cause a low TT4 in euthyroid dogs?
Breed variation, age, random fluctuations/diurnal rhythm, drugs, and non-thyroidal illness
34
What drugs can cause a decrease in TT4 and fT4, an increase in TSH, and clinical signs of hypothyroidism?
Sulfonamides
35
What drugs can cause a decrease in TT4, a decrease to normal fT4, a normal TSH, and no clinical signs?
glucocorticoids
36
What drug can cause a decreae in TT4 and fT4, an increase in TSH (but within the reference range), and no clinical signs?
Phenobarbital
37
What is non-thyroidal illness/sick euthyroid syndrome?
A syndrome where there are low thyroid levels in a patient with a fully functioning thyroid
38
What can cause sick euthyroid syndrome?
systemic illness, surgery, trauma, and malnutrition
39
How does sick euthyroid syndrome effect thyroid diagnostics?
It commonly decreases TT4, decreases fT4, and rarely increases TSH
40
What is the 'amazing-perfect' diagnosis for euthyroid sick syndrome?
low TT4 and fT4 with a high TSH
41
What should you do if a patient has a concurrent illness but you suspect a thyroid problem?
Wait until the concurrent illness has resolved
42
What is the use for fT4 screening test?
It is used in place of TT4 as a screening test or as a follow-up to a low TT4 if there is a non-thyroidal illness
43
What causes an elevated TSH level?
Lack of negative feedback in primary hypothyroidism
44
What is the use for a TSH test?
It is used in combination with TT4 and/or fT4 to support a diagnosis of primary hypothyroidism
45
True or False: Elevated TSH is highly specific for hypothyroidism
TRUE
46
What thyroid screening test is not helpful to test for hypothyroidism in dogs and why?
Total T3 because a large proportion of TT3 is not made in the thyroid gland, and it is not the predominate circulating hormone - 90% of hypothyroid dogs have a normal TT3
47
How can thyroiditis be diagnosed?
Via antibodies (serum thyroglobulin autoantibodies) in circulation during the inflammatory phase of disease
48
What is the thyroiditis antibody that circulates in dogs?
anti-thyroglobulin
49
How is the serum thyroglobulin autoantibodies test used?
To add support to suspicion of hypothyroidism when TT4/FT4+TSH is equivocal
50
What is the serum T3 and T4 autoantibody test used to do?
Clarify unexpected T4 or T3 results - it also supports diagnostic lymphocytic thyroiditis
51
When should you consider treatment trials?
When you have low TT4 and a normal TSH, normal TT4 and positive T4AA, and/or normal TT4 and high TSH with clinical suspician
52
How is hypothyroidism treated?
Levothyroxine sodium - 0.02 mg/kg BID
53
When is it critical to monitor treatment for hypothyroidism?
After 6-8 weeks of supplementation
54
With appropriate treatment, all clinical signs of hypothyroidism are ______.
reversible
55
What is important to inform your clients about the dermatologic abnormalities associated with hypothyroidism and treatment?
they can get worse before they get better
56
When monitoring response to treatment, what do you want to measure and when?
Serum T4 - 4-8 weeks after initiating therapy, when signs of thyrotoxicosis develop or when there has been minimal response to therapy T4 and TSH - 4-6 hours after administration of supplementation if autoantibodies are present, you cannot monitor with T4 and need to use fT4ED
57
Where should the post-dose T4 level be in response to treatment?
in the upper half or above the reference range
58
Where should the TSH levels be in response to treatment?
in the reference range
59
The dose of thyroid hormone supplementation should be reduced if the post-pill T4 is greater than what value?
6 micrograms/dl
60
What is the life expectancy of a dog with hypothyroidism?
it should be normal with normal treatment

Small Animal Medicine (100 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions