Thyroid Disease

Question 1

What is alemtuzumab?

Answer 1

An anti-CD52 monoclonal antibody

Question 2

What is the effect of of alemtuzumab?

Answer 2

Depletes autoreactive lymphocytes rapidly causing immune suppression followed by B cell recovery leading to B cell mediated autoimmunity

Question 3

What are the most common side effects of alemtuzumab?

Answer 3

Autoimmune disease – graves disease, ITP, haemolytic anaemia, anti GBM GN

Question 4

How does biotin cause spurious TFTs?

Answer 4

Excess of biotin occupies the binding sites in the assay causing falsely elevated levels of T3 and T4 and falsely low TSH

Question 5

What types of thyroid dysfunction are caused by amiodarone?

Answer 5

Hypothyroidism (most common)
Amiodarone-induced thyrotoxicosis type 1 (increased denovo thyroid hormone synthesis)
Amiodarone-induced thyrotoxicosis type 2 (destructive thyroiditis)

Question 6

How does amiodarone cause thyroid dysfunction?

Answer 6

Inhibits conversion of T4 to T3
Toxic to thyroid follicular cells
Iodine effect (high iodine content)

Question 7

What is the treatment for amiodarone induced thyrotoxicosis?

Answer 7

Prednisolone and carbimazole

Question 8

What is the difference in timing between AIT type 1 and AIT type 2?

Answer 8

AIT type 1 more common in early phase

AIT type 2 more common in late phase

Question 9

Which is more common AIT type 1 or 2?

Answer 9

AIT type 2

Question 10

Are thyroid autoantibodies positive in AIT?

Answer 10

May be positive in type 1

Question 11

Which responds more quickly to prednisolone AIT type 1 or 2?

Answer 11

Type 2

Question 12

What are the endocrine side effects of CTLA4 inhibitors (ipilimumab)?

Answer 12

Hypophysitis and hypothyroidism

Question 13

What are the endocrine side effects of PD-1 inhibitors (pembrolizumab, nivolumab)?

Answer 13

Hypo or hyperthyroidism

Question 14

What are the endocrine side effects of lithium?

Answer 14

Hypothyroidism, parathyroid hyperplasia, nephrogenic diabetes insipidus

Question 15

What is the mechanism of action for lithium causing hypothyroidism?

Answer 15

Inhibits pinocytosis

Question 16

What are predisposing factors to lithium hypothyroidism?

Answer 16

Female
Age > 40
Presence of TPO antibodies
Duration of use

Question 17

Which drugs increase thyroid binding proteins?

Answer 17

Oestrogen, SERM, methadone, heroin, mitotane, 5FU

Question 18

Which drugs decrease thyroid binding proteins?

Answer 18

Androgen, glucocorticoids, niacin

Question 19

What are the causes of primary hyperthyroidism?

Answer 19

Graves’ disease
Toxic MNG
Toxic adenoma
Early thyroiditis
Drugs
Excess iodine
Excess thyroxine
Hyperemesis gravidarum
Hydatidiform mole

Question 20

What are the pathognomonic signs of Graves disease?

Answer 20

Diffuse goitre
Thyroid eye disease
Peritibial myxoedema
Acropachy (clubbing)

Question 21

What are the signs of thyroid eye disease?

Answer 21

Bilateral proptosis
Periorbital oedema
Scleral injection
Lid retraction

Question 22

In which graves disease patients is radioactive iodine contraindicated?

Answer 22

Patients with severe thyroid eye disease – will exacerbate

Question 23

What is the differential diagnosis for primary hypothyroidism?

Answer 23

Hashimoto’s thyroiditis
Post radioiodine therapy
Post thyroidectomy
Subacute thyroiditis
Drugs
Neck irridation
Riedel’s thyroiditis (rare)
Thyroid infiltration e.g. amyloid (rare)
Congenital hypothyroidism

Question 24

What diseases is subclinical hyperthyroidism associated with?

Answer 24

Cardiovascular disease (AF, CCF, CAD), bone loss, fractures, dementia

Question 25

Which patients with subclinical hyperthyroidism should be treated?

Answer 25

Definitely if > 65 and TSH < 0.1

Maybe if just > 65 or TSH < 0.1

Question 26

Which patients with subclinical hypothyroidism should be treated?

Answer 26

If TSH > 10