clinical thyroid disease 2

Question 1

what is the difference between subclinical hyperthyroidism and compensated hyperthyroisism?

Answer 1

Question 2

describe thyroid hormone secretion in hyperthyroidism?

Answer 2

Question 3

what are primary causes of thyrotoxicosis?

Answer 3

Grave’s disease (70%)
Toxic Multinodular Goitre (20%)
Toxic adenoma

Question 3

what are secondary causes of thyrotoxicosis?

Answer 3

Pituitary adenoma secreting TSH

Thyrotoxicosis without hyperthyroidism
Destructive thyroiditis (post-partum, subacute [de Quervain’s], amiodarone-induced
Excessive thyroxine administration

Question 3

what is the incidence and prevalence of graves disease?

Answer 3

70-80% of all cases of hyperthyroidism
Incidence 2-3 per 1000 per year (Sex ratio 5:1)
Prevalence 1.9% female, 0.16% male

Question 4

what is graves disease

Answer 4

Autoimmune driven condition
thyroid peroxidase Antibodies
TSH receptor Antibodies
review personal/family history for concurrent autoimmune disease

Question 5

how is graves disease diagnosed?

Answer 5

Hyperthyroidism

Thyroid antibodies
(TSH Receptor antibodies)

thyroid eye disease, odema, goitre, clubbing, gynomastica

Question 6

what is multi-nodula goitre?

Answer 6

Most common cause of thyrotoxicosis in the elderly
Characteristic goitre and absence of Grave’s disease
Will not go into spontaneous remission

Question 7

what is subacutre (de quervains) thyroiditis?

Answer 7

Generally younger patients <50 years

Viral trigger (eg enteroviruses, coxsackie)

Often recall painful goitre +/- fever/myalgia; ESR increase

May require short term steroids and NSAIDs

Question 8

how can hyperthyroidism be treated?

Answer 8

radioactive iodine
surgery
antithyroid drugs - holding measure wont cure

beta blockers - reduce peipheral manifestations >(tremors, tachycardia)

Question 9

what are examples of antithyroid drugs?

Answer 9

Question 10

what is a common side effect of carbimaxzole?

Answer 10

rash

Question 11

what are side effects of propylthiouracil?

Answer 11

hepatotoxicity, ussually reserved for pregancy or short term use

Question 12

what are different regimines for antithyroid drugs?

Answer 12

block and replace - use high dose and maintain high dose, once patient euthyroid replace wuth thyroxin

titration regime - start high dose and reduce as things get better and maintin low dose for around 18 months

Question 13

what is the most common treatment plasn of antithyroid drugs?

Answer 13

ATD often on 1st occasion (40% chance of being cured and off medication).

Usually titration regimen, 12-18 months

Selected cases for long term low dose ATD
Elderly
Cardiac complications
Unwilling for RAI

Question 14

what is radioiodine?

Answer 14

has to be given with precautions as with stay in thyroid gland for 3 to 4 weeks

Patients usually choose ATD before RAI

Treat with ATD (stop 4-7 days before and after)

Elderly, Risk of cardiac problems
Usually given as high / ablative dose

70% risk of hypothyroidism
Avoided in severe eye disease

Question 15

38 year old woman
Graves Hyperthyroidism recurrence
TSH <0.02. FT4: 70 (N:10-25), Ft3: 25 (N:3-7)
TRAB: 18 (N: <1.5)

recommended
Carbimazole
Radioiodine - young children so chose surgery

Question 16

subclinical hyperthyroidism summary?

Answer 16

TSH suppressed
Normal Free thyroid hormones
Concerns:
Bone: decreased bone density in postmenopausal; No clear fracture data
AF: 3 fold increased risk in over 60s
Treatment considered ATD/RAI if persistent especially in elderly or those with increased cardiac risk

Question 17

Answer 17

Question 18

56 year old man
Tiredness and low energy
Funny TFTs
TSH: 2.84 (0.55-4.78mU/l)
FT4: 9 (10-25pmol/l)
Seen in Endocrine, Reduced libido for 4 years
LH<1, FSH 2.1, Testosterone <0.2
Peak cortisol on SST: 368nmol/l (N: >500)

Started Hydrocortisone first
Then Levothyroxine

Answer 18

secondary bhyperthyroidism