Thyroid Disease

Question 1

Features + rx of Subacute granulomatous thyroiditis

Answer 1

(viral infection, painful thyroid)
NSAIDs

Question 2

Rx + monitoring of hypothyroidism

Answer 2

Levothyroxine treatment of choice, start 12.5-50mcg/day
Repeat TSH q3-4 months until stable, then yearly

Question 3

Myxedema coma sx

Answer 3

Altered mental status, hypoventilation, hypothermia, hypotension, bradycardia, hyponatremia, hypoglycemia

Question 4

Rx of myxedema coma

Answer 4

Levothyroxine (T4) loading dose 200-400mcg IV, then 1.6mcg/kg/day IV
Liothyronine (T3) 5-20mcg followed by 2.5-10mcg q8h given with T4
Glucocorticoids (hydrocortisone 100mg IV q8-12h x2d) until coexisting adrenal insufficiency can be excluded
Supportive measures (ventilation, fluids, correction of hyponatremia and hypothermia)

Question 5

What are the receptor ab for Graves?

Answer 5

Graves (TSH receptor antibodies=TRAb)

Question 6

Causes of thyroid storm?

Answer 6

Trauma, surgery, RAI

Question 7

Sx of thyroid storm

Answer 7

Hyperthermia, tachycardia, N/V/D, dehydration, delirium, coma

Question 8

Treatment of thyroid storm

Answer 8

B-Blockers (Propranolol 60-80mg q4-6h)
Propylthiouracil 200mg PO q4h
Iodine solution (delayed 1h after PTU)
Iodinated radiocontrast
High-dose IV hydrocortisone 100mg IV q8h

Question 9

RF for hyperthyroidism

Answer 9

Diffuse/ nodular goitre
T1DM
Autoimmune disorder
Fam hx
Amiodarone, lithium, iodide

Question 10

When to check TSH

Answer 10

After med dose changes
Before initiating treatment
Periodically in stable pts

Question 11

rx for hyperthyroidism

Answer 11

Propranolol 10-40mg QID
Methimazole 5-120mg for 12-18mo then taper + DC
Radioactive iodine - single dose
Subtotal thyroidectomy - treatment of choice in pregnancy + pts <40 y/o

Question 12

Precipitants of hyperparathyroidism

Answer 12

thiazide diuretics, lithium, RT, MEN type 1 + 2a

Question 13

Lab results for hyperparathyroidism

Answer 13

high calcium, high PTH, low phosphate, high ALP

Question 14

Sx of hyperparathyroidism

Answer 14

bone pain, fragility fractures, kidney stones, polyuria, N/V, constipation, lethargy, depression, gout, reduced BMD

Question 15

Rx of hyperparathyroidism

Answer 15

parathyroidectomy, volume repletion + loop diuretics, pamidronate

Question 16

Causes of hypothyroidism

Answer 16

Chronic autoimmune thyroiditis (Hashimoto’s)
Postpartum thyroiditis
Iodine deficiency
Drugs: amiodarone, lithium, iodine
Central hypothyroidism
Pituitary adenoma or damage
Infiltrative: sarcoidosis, TB, granulomas)

Question 17

Who is at risk of hypothyroidism?

Answer 17

Women >45
1st trimester pregnancy
Trying to conceive
Post partum (6w-6mo)
Elderly
FHx
Autoimmune disease
Neck RT

Question 18

Ix for hypo

Answer 18

High TSH + low free T4 = hypothyroidism
Normal/ low TSH + low free T4 = central hypothyroidism
T3 if undetectable TSH + normal T4
Thyroid scan or MRI thyroid if goitre present

Question 19

RF for hyper

Answer 19

Diffuse/ nodular goitre
T1DM
Autoimmune disorder
Fam hx
Amiodarone, lithium, iodide

Question 20

Causes of hyper

Answer 20

Graves (antibody against TSH receptor) (High uptake, diffuse)
Toxic multinodular goitre (high uptake, nodular)
Toxic adenoma (high uptake, one ‘hot’ area)
Thyroditis (low uptake)
Treatment induced
Thyroid cancer

Question 21

Sx of hyper

Answer 21

Wt loss, heat intolerance
Lid lag, proptosis, periorbital edema, hair loss, goiter, thyroid bruits
Palpitations, tachy, AF, wide pulse pressure, HTN
Tremor, edema, pretibial myxedema, muscle weakness
Amenorrhea

Question 22

Ix for hyper

Answer 22

Low TSH high T4
MRI if high TSH + T4 (suspect TSH secreting pituitary adenoma)
Thyroid uptake if low TSH + high free T4
CBC and LFT at BL

Question 23

Lab results for thyroid storm

Answer 23

low TSH, high free T4, low Hb, high WBC, high glucose, high calcium, high LFTs

Question 24

Causes of hypo

Answer 24

Chronic autoimmune thyroiditis (Hashimoto’s)
Postpartum thyroiditis
Iodine deficiency
Drugs: amiodarone, lithium, iodine
Central hypothyroidism
Pituitary adenoma or damage
Infiltrative: sarcoidosis, TB, granulomas)

Question 25

RF for hypo

Answer 25

Women >45
1st trimester pregnancy
Trying to conceive
Post partum (6w-6mo)
Elderly
FHx
Autoimmune disease
Neck RT

Question 26

Sx of hypo

Answer 26

Fatigue, weakness, cold intolerance, weight gain
Depression, memory loss
Enlargement of tongue, hoarseness, goitre
Bradycardia, pericardial effusion, HTN, CHF
Muscle weakness
Constipation
Paresthesia, muscle cramps
Menorrhagie, amenorrhea, impotence
Periorbital edema, hair loss, lateral ⅓ eyebrow thin, brittle nails
Anemia

Question 27

Ix for hypo

Answer 27

High TSH + low free T4 = hypothyroidism
Normal/ low TSH + low free T4 = central hypothyroidism
T3 if undetectable TSH + normal T4
Thyroid scan or MRI thyroid if goitre present

Question 28

Management of Subclinical hypothyroidism

Answer 28

No treatment if TSH <10, normal T4, asymptomatic, not pregnant
Most normalize over next 5 yrs
Monitor annually
Treat w/ levothyroxine if:
Elevated TPO antibodies
Goitre
Fam hx of autoimmune dz
Pregnancy

Question 29

Rx for hypo

Answer 29

Tx if
TSH >10 + symptomatic
TSH 5-10 AND:
Elevated TPO antibodies
Goitre
Fam hx of autoimmune dz
Pregnancy

Question 30

What are the features of + when do you Rx: Subacute granulomatous thyroiditis

Answer 30

(preceding viral infection, painful thyroid) = usually self resolves, treat w/ NSAIDs

Question 31

Advice for pts on levo

Answer 31

Absorption affected by: high fibre, soy, coffee, calcium, iron, antacids, PPI, anticonvulsants
Take on empty stomach 30 mins before breakfast

Question 32

Thyroid storm Rx

Answer 32

thionamides e.g. methimazole (blocking synthesis), propranolol, iodine, bile acid sequestrant (cholestyramine)

Question 33

Rx for graves

Answer 33

thionamides e.g. methimazole (blocking synthesis), propranolol, iodine, bile acid sequestrant (cholestyramine), radiation, thyroidectomy

Question 34

When to screen for hypothyroidism

Answer 34

sx, at risk (pregnancy, prev thyroid dz, prev radiation, pituitary disorder), taking replacement

Question 35

Next steps if hyperthyroid on labs

Answer 35

BB 6-8 wks, radioactive iodine uptake (unless Graves or pregnant or breastfeeding)

Question 36

thyroid nodule workup

Answer 36

TSH, thyroid US (>1cm, taller than wide), FNA for cytology)

Question 37

What are features of a suspicious thyroid nodules?

Answer 37

> 1cm, irregular surface, taller than wide, calcifications

Question 38

Hypothyroidism signs

Answer 38

dry skin, bradycardia, wt gain, delayed reflex relaxation, edema

Question 39

Hyperthyroidism signs

Answer 39

diaphoresis, tachycardia, wt loss, goiter, tremor, thinning of hair, lid lag, exophthalmos