Hyperthyroidism Flashcards
What are the cardiac ssx of hyperthyroidism?
HTN
Tachycardia
Increased contractility
What are the sequelae of the cardiac effects of hyperthyroidism?
A0fib
high output failure
What is Grave’s dermopathy
Thickening of the skin, especially in the dependent areas
What are the eye findings of hyperthyroidism?
Lid lag
Lid retraction
What are the eye ssx that are specific to Grave’s disease?
Proptosis
Ophthalmoplegia
Periorbital edema
What is the pathophysiology of primary and secondary hyperthyroidism?
Primary = inherent thyroid issue Secondary= increased TSH levels
What primary pathology may cause hyperthyroidism, but is not causing increased synthesis?
Inappropriate leakage of premade T4
What happens to the TSH levels and FT$ or FT# levels?
Decreased TSH, increased FT4/FT3
What is subclinical hyperthyroidism?
Normal ft4, but increased TSH
What is the basis for the radionuclide scan?
Thyroid uptake and scan after pt given radioactive iodine I-123
Who is usually affected with Grave’s?
Young females
What is the cause of Grave’s disease?
Antibodies to TSH receptors stimulate growth and hormone productions
What are the antibodies that are found with Grave’s disease?
TRAb
TSIg
True or false: there usually is no familial predisposition of Grave’s disease
False
What are the ssx of Grave’s disease?
Hyperthyroidism + Graves ophthalmopathy + dermopathy
What is Graves ophthalmopathy?
abs stimulate inflammation of the eyes in the orbit, as well as deposition of GAGs, lipogenesis, and orbital muscle hypertrophy.
What are the risk factors for developing Grave’s ophthalmopathy?
Smokers
High TSI
True or false: Grave’s ophthalmopathy correlates with the thyroid status
False–independent
What causes the goiter formation with Grave’s disease?
TSH stimulation
What is the sensitivity/specificity of a bruit in Grave’s disease?
Insensitive, but specific
What are the uptake and scan findings with Grave’s disease?
Uptake is NOT low
Scan is homogenous
What is the treatment for Grave’s disease?
Beta blockers
Steroids
Antithyroids
What is the MOA of antithyroids?
Inhibits the organification of iodine to iodotyrosine and coupling
What is the MOA of Propylthiouracil? Use? Side effects?
Inhibits the organification of iodine to iodotyrosine and coupling
Treats hyperthyroidism
Hepatitis, agranulocytosis
What are the labs that should be monitored with Grave’s disease?
Thyroid function
CBC
Transaminases
How long is PTU used for Grave’s disease?
Less than two years, since a bit less than 50% have a long term remission
What is the permanent treatment for Grave’s disease?
Radioactive ablation of thyroid gland, with I-131, causing destruction in 4 weeks to 6 months
What is the goal of radioactive ablation of the thyroid? Why is this used instead of chronic PTU?
Destroy it to give them Levothyroxine
PTU has more side effects than levothyroxine
What are the radiation precautions that must be taken for radioactive ablation of the thyroid?
no prego
No sexy time
Sleep alone
What may happen with the eye disease of Grave disease with radioactive ablation of the thyroid?
May worsen
What are the prep procedures for a thyroidectomy?
- Antithyroids to render euthyroid
- Beta blockers
Why give SSKI preop of a thyroidectomy?
To decrease T4 and vascularity
Who should get a thyroidectomy as opposed to radioactive ablation?
Pts on amiodarone
Prego
What are “hot” nodules?
autonomously functioning nodule
What is Plummer’s disease? IN whom is this common?
Toxic multinodular goiter
Older patients greater than 50 yo
What is the pathophysiology of autonomously functioning nodules?
Hyperplasia of follicular cells, overproduction of T4 independent of T4
What are the PE finding with autonomously functioning nodules?
Nodular thyroid
What are the chances that plummer’s disease will resolve on its own
will not
What are the uptake and scan findings of autonomously functioning nodules?
Patchy hyperactivity, with other areas suppressed
What is the treatment for autonomously functioning nodules? Why is the outcome for this different than in other thyroid diseases?
Radioactive ablation. This will not render them hypothyroid, since only the overactive areas pick up the I, while the under active areas do not
Why are antithyroids contraindicated for autonomously functioning nodules?
Will not spontaneously resolve like Grave’s disease
Side effects more likely the longer you’re on it
What is the usual thyroid levels with thyroiditis?
Inflammation of the thyroid causes leakage of preformed T3/T4
What are the etiologies of thyroiditis?
Viral
Radiation
Iodine exposure
Postpartum
What are the PE findings with thyroiditis?
Usual hyperthyroid signs
Tender thyroid
What are the thyroid uptake scans with thyroiditis? Why?
Low, since you’re not making more hormone, you’re just leaking.
What is the treatment for thyroiditis?
- NSAIDs
- Prednisone
- beta-blockers
- Antithyroids
What is the natural h/o thyroiditis?
Triphasic—Hyperthyroid-euthyroid–hypothyroid
What is the role of radioactive Iodine and antithyroids in thyroiditis?
Since it is not an overproduction pathology, antithyroids and radioactive ablation are not very useful
What is the typical cause of Iodine-induce hyperthyroidism?
Pts who take amiodarone, or other high dose iodine treatments
How do you diagnose amiodarone induced hyperthyroidism?
US may show increased vascularity, but not specific
What are the results of thyroid uptake with amiodarone?
Low
What are the therapeutic options for amiodarone induced hyperthyroidism?
Glucocorticoid
Why isn’t radioactive ablation or PTU useful for amiodarone induced hyperthyroidism?
Thyroid already supersaturated with iodine
Antithyroids only inhibit new uptake of iodine–again, already super saturated
Why is it difficult to treat amiodarone-induced hyperthyroidism?
Very long half-life, and needed for cardiac reasons
What is the most effective means for treating amiodarone hyperthyroidism?
Thyroidectomy
What are the labs like with a TSH-producing pituitary tumor?
Increased T4, with non suppressed or increased TSH
What are the clinical features of a TSH producing pituitary adenoma?
Hyperthyroid features
Goiter
Bitemporal hemianopsia
What are the diagnostic tests for a TSH producing adenoma?
High alpha subunit
MRI showing pituitary adenoma
What is the treatment for a TSH producing pituitary adenoma?
Transsphenoidal resection
Octreotide
What is hCG-mediated hyperthyroidism?
HCG weakly stimulate the thyroid, but TSH will deccrase
In what conditions is hCG-mediated hyperthyroidism seen in (2)?
- Hyperemesis gravidarum
- Molar pregnancy
If there is no pathological cause of hCG mediated-hyperthyroidism, what is the treatment?
No Rx needed
When should hCG-mediated hyperthyroidism be treated? What should be used?
- If T4 elevated
- PTU first trimester
- Methimazole
What is thyroid storm?
Severe exacerbation of a preexisting hyperthyroidism, causing:
- tachy
- hyperthermia
- n/v/d
- Mental status change
What are the triggers for thyroid storm?
- Omission of anti thyroid drugs
- surgery
- infx
- MI
- CVA
What is the treatment for thyroid storm?
- Supportive (cooling, IVFs, oxygen etc)
- Beta blockers
- Glucocorticoids
- antithyroids
- Iodine
What is the mortality rate of thyroid storm?
20-30%
What is euthyroid sick syndrome?
Fluctuation of thyroid hormones during some sort of stress, but does not actually reflect any thyroid pathology
What are the classic lab findings of euthyroid sick syndrome?
TSH low
FT4, FT3 low
rT3 high
What is the purpose of putting patients on SSKI prior to surgery?
Decreases T4 secretion (through Wolff-Chaikoff phenomenon)
Decreases vascularity of thyroid gland
What is the phenomenon of increased T4 synthesis with increase iodine concentrations?
Jod Basedow effect
What is the phenomenon of decreased T4 synthesis with very highly increase iodine concentrations?
Wolff-Chaikoff phenomenon
What is Type 1 amiodarone induced hyperthyroidism?
Increases synthesis of T4 d/t Jod Basedow effect
What is Type 2 amiodarone induced hyperthyroidism?
Thyroiditis
How can HCG reduce hyperthyroidism?
HCG’s alpha subunit, which TSH has in common, may cause feedback inhibition
