hypothyroidism

Question 1

Hypothyroidism

What are S&S of hypothyroidism:

Neuropsych
Neuromuscular
Skin/Hair
Voice
Weight
CVS
Goitre 
Hot/Cold/diaphoresis 
Eyes
GI
Pituitary fntn

Answer 1

Neuropsych
 - depression 
 - decreased mental function 
Neuromuscular
 - physical tiredness
 - paresthesia
 - hypokinesis
 - hyporeflexia
Skin/Hair
 - coarse, dry skin 
 - coarse, brital hair 
Voice
 - hoarseness 
Weight
 - weight gain (not in ped's) 
CVS
 - bradycardia
 - isolated DBP 
Goitre 
 - yes
Hot/Cold/diaphoresis
 - lack sweating 
 - cold intolerance  
Eyes
 - periorbital edema 
GI 
 - constipation 
Pituitary fntn
 - menorrhagia

Question 2

Hypothyroidism

When testing for hypothyroidism, if TSH is high, and fT4 is normal, next step is to check fT3. True/False

Answer 2

False

If fT4 is normal consider subclinical hypothyroidism

Question 3

Hypothyroidism

What will TSH/T3T4 be in sick euthyroid (although testing not normally indicated for this condition)

Answer 3

all low, as the patient recovers, TSH may become elevated

Question 4

Hypothyroidism

What are causes of central hypothyroidism?

Answer 4

• injuries & infections
• vascular accidents
• pituitary tumours, invasive or compressive lesions
• autoimmune
• infiltrative disease (of the pituitary gland)
• congenital (most common cause intellectual disability –> thyroid screening newborns)

Question 5

Hypothyroidism

After initiating synthroid, what do you monitor to titrate dose and when do you recheck BW?

Answer 5

TSH, 6 weeks?

Question 6

Hypothyroidism

What is the most common cause of hypothyroidism?

Answer 6

Hashimoto’s

Question 7

Hypothyroidism

What blood test confirms autoimmune thyroiditis?

Answer 7

anti-TPO

Question 8

Hypothyroidism

If someone has a goitre, check Tg and antiTg for ( thyroglobulin/antithyroglobulin) to rule out thyroid carcinoma

True/False

Answer 8

false

Tg/anti-Tg are tumor markers for patients who have undergone previous tx for thyroid CA. Generally not indicated for intact thyroid.

Question 9

Hypothyroidism

What is primary, secondary and tertiary etiologies for hypothyroidism?

Answer 9

primary - thyroid
secondary - pituitary
tertiary - hypothalamus

Question 10

Hypothyroidism

What is another word for hypothyroidism that refers to periorbital/facilal edema?

Answer 10

myxedema

Question 11

Hypothyroidism

Risk factors for thyroid disease

Answer 11

• men: age ≥ 60 years
• women: age ≥ 50 years
• personal history or strong family history of thyroid disease
• diagnosis of other autoimmune diseases
• past history of neck irradiation
• previous thyroidectomy or radioactive iodine ablation
• drug therapies such as lithium and amiodarone
• dietary factors (iodine excess and iodine deficiency)
• certain chromosomal or genetic disorders (e.g., Turner syndrome, Down syndrome and mitochondrial disease)
- hypothyroidism females are 5-8 X higher prevalence

Question 12

Hypothyroidism

When would you treat subclinical hypothyroidism?

Answer 12

TSH > 10, or TSH < 10 + symptomatic (less common)

Question 13

Hypothyroidism

How often do you screen TSH if patient is taking lithium or amiodarone?

Answer 13

Q3-6months

Question 14

Hypothyroidism

How often do you recheck TSH for patients with subclinical hypothyroidism or those or are not taking pharmocologic tx?

Answer 14

Q6-12 months

Question 15

Hypothyroidism

When synthroid dose is stabilized, how often do you monitor TSH?

Answer 15

Q6-12 months

Question 16

Hypothyroidism

When to refer/consult endocrinology for hypothyroidism?

Answer 16

• < 18 years
• unresponsive to tx
• pregnant
• goitre/nodule/structural changes (and order U/S)
• myxedema

Question 17

Hypothyroidism

How to initiate/titrate levothyroxine

Answer 17

• start at 25-50mcg (1.6-1.7mcg/kg/d, but no one does this)
• recheck in 6 weeks
• titrate by 12.5 to 25 mcg/day every 8 weeks
• looking for change in TSH (UNLIKE hyperthyroidism where dose is titrated per fT4)

Question 18

Hypothyroidism

pt counselling re: taking synthroid

Answer 18

• same time each day!!
• empty stomach!!!
• 30-60 min AC breakfast or > 3 hrs PC supper