Thyroid

Question 1

What would TFTs be in thyrotoxicosis?

Answer 1

Low TSH
High free T4

Question 2

What are TFTs in primary hypothyroid?

Answer 2

TSH high
Free T4 low

Question 3

What are TFTs in secondary hypothyroid?

Answer 3

TSH low
Free T4 low

Question 4

What are TFTs in sick euthyroid?

Answer 4

Low/normal TSH
Low free T4
Low T3

Question 5

What are TFTs with steroid therapy?

Answer 5

Low TSH
Normal T4

Question 6

What causes secondary hypothyroid?

Answer 6

Pituitary failure - eg post surgery/RXT, pituitary adenoma

Question 7

What is the initial management of Grave’s disease?

Answer 7

Symptomatic management - propranolol

Question 8

What are the options for Grave’s disease?

Answer 8

Anti-thyroid drugs - carbimazole
Radioiodine treatment

Question 9

What are the options for treatment with carbimazole?

Answer 9

Standard therapy
Block and replace therapy

Question 10

How is standard carbimazole therapy delivered?

Answer 10

Commenced at 40mg and gradually reduced to maintain euthyroid over 12-18 months

Question 11

How is block-and-replace treatment delivered?

Answer 11

Carbimazole commenced at 40mg and thyroxine added when patient euthyroid
lasts 6-9 months

Question 12

What are the benefits of standard carbimazole therapy?

Answer 12

Fewer side effects

Question 13

What is the main risk of carbimazole?

Answer 13

Agranylocytosis

Question 14

What are indications for radio iodine treatment?

Answer 14

Relapse following anti-thyroid drugs or resistant to ATD treatment

Question 15

What are contraindications for radioiodine?

Answer 15

Pregnancy
Age <16
Thyroid eye disease - relative contraindication

Question 16

What are the long term implications of radioiodine treatment?

Answer 16

Most require thyroxine at 5 years post
Must avoid pregnancy for 4-6 months following treatment

Question 17

What are indications for treatment with anti-thyroid drugs?

Answer 17

Symptoms of thyrotoxicosis
Significant risk of hyperthyroid complications eg elderly, cardiovascular disease

Question 18

What antibodies are associated with Grave’s disease?

Answer 18

TSH receptor stimulating antibodies - 90%
Anti-thyroid peroxidase antibodies

Question 19

What is seen on Thyroid scintigraphy in Grave’s?

Answer 19

Diffuse homogenous increase uptake

Question 20

What are signs specific to Grave’s disease?

Answer 20

Eye signs - 30% patients
Pretibial myxoedema
Thyroid acropachy - digital clubbing, soft tissue swelling of hands and feet, periostea new bone formation

Question 21

What are causes of hyperthyroid?

Answer 21

Grave’s
Toxic multi nodular goitre
Acute phase subacute thyroiditis
Acute phase post part thyroiditis
Acute phase Hashimoto’s
Amiodarone
Contrast

Question 22

What is toxic multi nodular goitre?

Answer 22

Multiple autonomously functioning thyroid nodules resulting in hyperthyroidism

Question 23

What is seen on scintigraphy in toxic multi nodular goitre?

Answer 23

Patchy uptake

Question 24

How is toxic multi nodular goitre managed?

Answer 24

Radioiodine therapy

Question 25

When is a thyroid storm normally seen?

Answer 25

Patients with known thyrotoxicosis following - surgery - trauma - infection - acute iodine load

Question 26

What are the features of thyroid storm?

Answer 26

fever >38.5C Tachycardia N&V Confusion HTN Heart failure Abnormal LFTs

Question 27

What is the management of thyroid storm?

Answer 27

Symptomatic - eg paracetamol Treat cause Beta blockers Anti-thyroid drugs - methimazole, propylthiouracil Ligol's iodine Dex 4mg IV QDS - blocks conversion of T4 to T3

Question 28

What is the timescale of subacute thyroiditis?

Answer 28

Phase 1 - hyperthyroid = 3-6 weeks Phase 2 - euthyroid = 1-3 weeks Phase 3 - hypothyroid = weeks to months

Question 29

How does subacute thyroiditis normally present?

Answer 29

Hyperthyroid Painful goitre Raised ESR

Question 30

What is seen on thyroid scintigraphy in subacute thyroiditis?

Answer 30

Globally reduced uptake

Question 31

What is the management of subacute thyroiditis?

Answer 31

Usually self limiting Steroids if severe Pain - NSAIDs

Question 32

What causes thyroid eye disease?

Answer 32

Autoimmune response to auto antigen causes retro-orbital inflammation, which causes glycosaminoglycan and collagen deposition

Question 33

What are the complications of thyroid eye disease?

Answer 33

Exposure keratopathy - most common Optic neuropathy Strabismus and diplopia

Question 34

What causes optic neuropathy in thyroid eye disease?

Answer 34

Extraocular muscles compress optic nerve

Question 35

What is the management of thyroid eye disease?

Answer 35

Steroids Radiotherapy Surgery Avoid radioiodine - can cause worsening of inflammatory symptoms

Question 36

What is the biggest risk factor for thyroid eye disease?

Answer 36

Smoking

Question 37

What autoantibodies are associated with Hashimoto's?

Answer 37

thyroid peroxidase Anti-thyroglobulin

Question 38

What is Hashimoto's associated with?

Answer 38

Other autoimmune conditions MALT lymphoma

Question 39

What doses should levothyroxine be started at?

Answer 39

50-100micrograms >50yo , cardiac disease or severe hypothyroid - 25 micrograms

Question 40

When are TFTs checked after starting levothyroxine?

Answer 40

8-12 weeks

Question 41

What adjustments should be made to levothyroxine in pregnancy?

Answer 41

Increase by minimum of 25-50micrograms

Question 42

What are the important interactions of levothyroxine?

Answer 42

Iron, calcium carbonate - reduce absorption of levothyroxine - give at least 4 hours apart

Question 43

What are causes of hypothyroid?

Answer 43

Hashimoto's Subacute thyroiditis Reidel thyroiditis After thyroidectomy/radioiodine Drugs Dietary iodine

Question 44

What drugs cause hypothyroid?

Answer 44

Lithium Amiodarone Carbimazole

Question 45

What is Reidel's thyroiditis?

Answer 45

Dense fibrois tissue replacing normal thyroid

Question 46

What are the features of Reidel's thyroiditis?

Answer 46

Hard, fixed, painless goitre Associated with retroperitoneal fibrosis Middle aged women