Thyroid Flashcards by Sarah Muse

What is the function of the thyroid?

metabolism
regulate long bone growth
brain development

How well did you know this?

Not at all

Perfectly

Hormone overview for thyroid

TRH–>TSH–>T3/T4

How well did you know this?

Not at all

Perfectly

Physiology of hormone release in the thyroid

hypothalamus releases TRH–>triggers anterior pituitary to release TSH–>triggers the thyroid to release thyroxine–>gets converted to T3/T4 in the tissue

How well did you know this?

Not at all

Perfectly

Why iodine important to the thyroid

needed to produce T3 and T4

How well did you know this?

Not at all

Perfectly

What is thyrotoxicosis

elevated unbound thyroid hormone circulating in the body

How well did you know this?

Not at all

Perfectly

What is the #1 cause of hyperthyroidism in the US

Grave’s disease

How well did you know this?

Not at all

Perfectly

Typical age of diagnosis of hyperthyroidism? gender?

occurs in women 20-40 years of age

How well did you know this?

Not at all

Perfectly

What are the primary causes of hyperthyroidism

Grave’s disease
toxic multinodular goiter
toxic nodular goiter

How well did you know this?

Not at all

Perfectly

Symptoms of hyperthyroid

irritability/nervousness/anxiety
sweating
fatigue
muscle weakness
palpitations
increased bowel movements
SOB
heat intolerance
menstrual irregulatities

How well did you know this?

Not at all

Perfectly

Finding specific for Grave’s disease

opthalmopathy/exophthalmos
infiltrative dermopathy
thyroid acropathy
goiter with bruit

How well did you know this?

Not at all

Perfectly

Physical exam findings for hyperthyroid.
   skin/nails
   HEENT
   cardiac
   neuro
   endocrine

skin/nails:

pruritus
moist skin
thinning hair
hyperpigmentation
oncholysis

HEENT:

lid lag
exopthalmous
goiter or nodules

Cardiac:
-tachycardia/afib

Neuro:

fine tremor
hyperreflexia

Endocrine:
-weight loss despite increased appetite

How well did you know this?

Not at all

Perfectly

Labs in hyperthyroidism.
   TSH
   Free T4
   Total T3
   antibodies
   Serum cholesterol
   calcium

TSH- decreased
T3/T4- increased
antibodies will be present in Grave's disease
serum cholesterol- decreased
hypercalcemia

How well did you know this?

Not at all

Perfectly

What imaging studies are done in hyperthyroid? what do they show?

Nuclear scintigraphy with radioactive iodine uptake

shows diffuse, increased uptake

How well did you know this?

Not at all

Perfectly

Which causes of hyperthyroid present in the elderly

toxic multinodular goiter

- toxic nodular goiter

How well did you know this?

Not at all

Perfectly

What would a thyroid scan show with toxic nodular.multinodular goiter

irregular or diminished uptake

How well did you know this?

Not at all

Perfectly

Treatment options for hyperthyroid

symptomatic treatment
antithyroid drugs (thionamides)
radioactive iodine treatment
surgery

How well did you know this?

Not at all

Perfectly

What is the treatment of choice for hyperthyroid

radioactive iodine treatment

How well did you know this?

Not at all

Perfectly

Symptomatic treatment for hyperthyroid

-rehydration
-beta blocker
propanolol
atenolol
metoprolol

How well did you know this?

Not at all

Perfectly

Thionamides used for hyperthyroid

Methimazole (preferred)

- PTU (pregnancy)

How well did you know this?

Not at all

Perfectly

What is the end result of radioactive iodine treatment

permanent hypothyroid, must give levothyroxine

How well did you know this?

Not at all

Perfectly

In what patients is surgery indicated for hyperthyroid

children
pts with large goiters
non compliant patients

How well did you know this?

Not at all

Perfectly

What is a thyroid storm

complication of untreated hyperthyroidism

How well did you know this?

Not at all

Perfectly

What typically triggers a thyroid storm

major stressor

trauma
heart attack
infection

How well did you know this?

Not at all

Perfectly

Clinical presentation of thyroid storm

fever
tachycardia
hypertension
neurological and GI abnormalities
delerium
N/V/D
heart failure
pulmonary edema

How well did you know this?

Not at all

Perfectly

How do you treat a thyroid storm

- antipyretics - IV rehydration - beta blocker - IV thiourea - Lugol's solution 1 hr after thiourea - gluccocorticoids

What is subacute thyroiditis

de Quervian thyroiditis | -typically caused by a viral infection

What is the #1 cause of hypothyroid in developing countries

iodine deficiency

What is the most common cause of hypothyroid in the US

Hashimoto

Causes of hypothyroid

- autoimmune thyroiditis (hashimoto's) - thyroidectomy - central hypothyroidism

Symptoms of hypothyroidism

- fatigue/lethargy - depression - weakness - arthralgia - constipation - headache - paresthesias - cold intolerance - infertility

Exam findings for hypothyroidism

- dry skin - weight gain - thinning of hair - puffy face/eye - goiter - bradycardia - delayed reflex

Labs for Hashimoto's

- TSH (elevated) - T3/T4 (low) - antibodies - hyponatremia - hypoglycemia - anemia - decrease basic metabolic rate

pathophys of chronic lymphocytic thyroiditis

invasion of B lymphocytes in the thyroid gland

Treatment of choice for hypothyroid

levothyroxine (T4)

Myxedema coma

severe hypothyroidism

Who is myxedema coma most often seen in

elderly that stop taking their medication

Signs of myxedema coma

- hypothermia - hypoventilation - hyponatremia - hypoglycemia - hypotension - rhabdo/AKI

Treatment of myxedema coma

- high IV dose levothyroxine - warm with blankets - intubation - treat infections - hydrocortizone if adrenal insufficiency present

Euthyroid sick syndrome

abnormal finding on a thyroid function tests that occur in the setting of a nonthyroidal illness

Common illnesses that cause euthyroid sick syndrome

MI, DKA, CRF, cirrhosis

What are the TSH levels in euthyroid sick syndrome? T3/T4?

TSH is NORMAL | normal to low T3/T4

What levels are elevated in euthyroid sick syndrome

cortisol

What causes subacute lymphocytic thyroiditis

- autoimmune mediated | - exposure to certain medication (lithium, interleukin-2, interferon-alpha, tyrosine kinase inh)

What do most patients with post partum thyroiditis get

Hashimoto's

Signs of subacute granulomatous thyroiditis

- low grade fever - viral sx - painful nodule - dysphagia

What is chronic lymphocytic thyroiditis

Hashimoto's thyroiditis

What drugs can cause thyroiditis

- amiodarone - lithium - phenytoin - radioactive iodine

What two values are elevated in subactute granulomatous thyroiditis but not subactue lymphocytic thyroiditis

SED rate and CRP

Amiodarone thyroiditis type 1

active production of excessive hormones due to too much free iodine

Amiodarone thyroiditis type 2

destructive thyroiditis that releases stored hormones

How do you treat thyroiditis

- treat symptoms - levothyroxine in hypo * do not give thionamide if hyper*

Risk factors for thyroid cancer

- history of radiation exposure - multiple endocrine neoplasia (MEN) - family history

Four types of thyroid cancer

papillary, follicular, medullary, anaplastic

What is present in papillary thyroid cancer

Psammoma bodies- cleaved nuclei

What put a person at an increased risk for papillary thyroid cancer

Hashimoto's

What is medullary thyroid cancer associated with

MEN 2A and 2B

Where is follicular thyroid cancer more common

iodine deficient regions

How does papillary thyroid cancer spread

lymphatic and hematogenously (bone, lung)

How does follicular thyroid cancer spread

hematogenously (bone,lung, CNS)

What are poor prognostic indicators for follicular thyroid cancer

- hurthle cell - >4cm - >50 y/o - distant mets - vascular invasion

What causes anaplastic thyroid cancer

inactivation of the p53 gene

Which thyroid cancer has the worse prognosis

anaplastic

What is the diagnostic tool of choice for thyroid cancer

fine needle aspiration

What labs are checked fro medullary thyroid cancer

- serum calcitonin and CEA | - PCR germline mutation

Hot vs cold. Which one is better

Hotter the better

Treatment of thyroid cancer

thyroidectomty