Thyroid Hormones #2 Flashcards
1
Q
Thyroid Conditions that don’t develop Goiter?
A
- Secondary and Tertiary Hypothyroidism (⬇️TSH and/or ⬇️TRH)
2
Q
Why can iodine deficiency have goiter, but be euthyroid?
A
- ⬇️Iodine Deficiency
- ⬇️T4 and ⬆️T3
- ⬇️T4 —> ⬇️Negative Feedback —> ⬆️TSH —> ⬆️Hyperplasia and Hypertrophy —> GOITER
3
Q
Most common cause of Hypothyroidism?
A
Hashimoto’s Thyroiditis
4
Q
Main defect on Hashimoto’s Thyroiditis ?
A
- Antibodies vs TPO
5
Q
Main clinical hormonal defects on Primary Hypothyroidism?
A
- ⬆️TSH / ⬇️T4
6
Q
Another name for Postnatal Hypothyroidism?
A
- Cretinism
7
Q
Main pathological features of Cretinism?
A
- Dwarfism
- Mental Retardation
- Pot belly
- Macroglossia
8
Q
Why does Hypothyroidism cause dwarfism or short stature in children?
A
- Thyroid hormone is a permissive drug for growth
9
Q
Main radiological sign in Hypothyroidism in children?
A
- Stippled Epiphysis (multiple ossification centers)
10
Q
What is the Wolff-Chaikoff effect?
A
- ⬆️⬆️amounts of Iodine ⬇️thyroid function
11
Q
Drugs that induce Hypothyroidism through the Wolff-Chaikoff effect?
A
- Amiodarone
2. Lithium
12
Q
In what condition is the Wolff-Chaikoff effect more effective ?
A
- Graves’ Disease (Primary Hyperthyroidism)
13
Q
Pathophysiology of Graves’ Disease?
A
- ⬆️IgG vs TSH receptor un thyroid —> ⬆️T4 production (thyroid stimulating antibodies )
14
Q
Drug that prevents conversion of T4 to T3?
A
Dexamethasone
