(!) Hypothyroidism

Question 1

Management of hypothyroidism

Answer 1

Thyxoxine-dose from 50-100 micrograms PO OD –can start on either and then repeat TFT’s-and check if dose is right
Take on empty stomach

during pregnancy-increase 50% by 6 weeks

Question 2

Define hypothyroidism

Answer 2

Clinical state resulting from low circulating T3/4
Mainly caused by primary -thyroid gland problems
and rarely from secondary/central hypothyroidism

Question 3

Aetiology and risk factors of hypothyroidism

Answer 3

Central-most commonly pituitary adenoma (prolactin) causing compression/loss of function of PIT gland
TB

secondary-
Autoimmune (hashimoto’s) is the main cause in the world
IODINE deficiency-common in developing world
Other causes-iatrogenic from surgery, or trauma
De quervains thyroiditis also causes hypo
Some drugs-lithium, amiodarone

Risk factors
Women 8x> Men Hashimoto
Age increase
Iodine deficiency
FHx of hashimoto
MS

Question 4

Epidiemology of hypothyroidism

Answer 4

Ridiculously common
In developing world-iodine deficiency is main cause
Subclinical-white-5% of population
Lower in other

Overall 7.5% of women in UK have high TSH, 3% of men
clinical Sx are rarer

Question 5

Signs and Sx of hypothyroidism

Answer 5

Tons of non-specific-fatigue/lethargy
Feeling slow, etc
-> why TSH is part of fatigue screen and need to check
Often subclinical-high TSH but no Sx

Weakness, lethargy, myalgia
Weight gain, appetite loss
Cold intolerance
Depression, dry skin
bradycardia, hypertension
delayed reflexes
oligomennrhoa, 

carpal tunnel

central-might get bitemporal hemianopia

Question 6

Investigations of hypothyroidism

Answer 6

TSH-raised

T3/T4-low -help for degree of hypo, or subclinical

Question 7

Complications of hypothyroidism

Answer 7

The main one you need to avoid by delaying diagnosis-
often after stress–Myxodemal coma
Delirium, hypothermia, big Brady, hypoglycemia

angina and AF can occur in over treatment

central-if its hypopit-cant replace T3/4 without Steroids-or adrenal crisis

Question 8

Prognosis of hypothyroidism

Answer 8

Need lifelong therapy
But excellent after proper dosage has been determined

central-depends on cause-and type (micro vs macro), (prolactin vs GH vs non functional)