Thyroid

Question 1

TFTs in hyperthyroidism

Answer 1

Low TSH
High T3 + T4

Pituitary adenoma (High TSH and T3 T4)

Question 2

TFTs in Primary Hypothyroidism

Answer 2

High TSH

Low T3/T4

Question 3

TFTs in Secondary Hypothyroidism

Answer 3

Low TSH

Low T3/T4

Question 4

What antibodies are most relevant thyroid autoantibody in autoimmune thyroid disease - Graves, Hashimoto’s ?

Answer 4

Antithyroid Peroxidase (anti-TPO) Antibodies

Question 5

What is the use of measuring Antithyroglobulin Antibodies?

Answer 5

Usually present in Grave’s Disease, Hashimoto’s Thyroiditis and thyroid cancer

Can be present in normal individuals

Question 6

What are TSH Receptor Antibodies?

Answer 6

Autoantibodies that mimic TSH, bind to the TSH receptor

Cause of Grave’s

Question 7

What can radioactive iodine tell you about thyroid patologies?

Answer 7

Diffuse high uptake is found in Grave’s Disease

Focal high uptake is found in toxic multinodular goitre and adenomas

Cold” areas (i.e. abnormally low uptake) can indicate thyroid cancer

Question 8

What is pretibial myxoedema?

Answer 8

Discoloured, waxy, oedematous appearance to the skin over ant. aspect of the leg

Specific to Grave’s disease

Reaction to the TSH receptor antibodies

Question 9

Causes of hyperthyroidism

Answer 9

Grave’s disease
Toxic multinodular goitre
Solitary toxic thyroid nodule
Thyroiditis (e.g. De Quervain’s, Hashimoto’s, postpartum and drug-induced thyroiditis)

Question 10

What are the features of hyperthyroidism?

Answer 10

Anxiety and irritability
Sweating and heat intolerance
Tachycardia
Weight loss
Fatigue
Frequent loose stools
Sexual dysfunction

Question 11

Unique features of Grave’s

Answer 11

Diffuse Goitre (without nodules)
Graves Eye Disease
Bilateral Exopthalmos
Pretibial Myxoedema

Question 12

Unique features of Toxic Multinodular Goitre

Answer 12

Goitre with firm nodules
Most patients are aged over 50
Second most common cause of thyrotoxicosis (after Grave’s)

Question 13

What is a solitary toxic nodule?

Answer 13

Single abnormal thyroid nodule is acting alone to release thyroid hormone

Usually benign adenomas

Treated with surgery

Question 14

What is De Quervain’s thyroiditis?

Answer 14

Presentation of a viral infection with fever, neck pain and tenderness, dysphagia and features of hyperthyroidism

Hyperthyroid phase followed by hypothyroid phase as the TSH level falls due to negative feedback

Question 15

How is De Quervain’s thyroiditis treated?

Answer 15

Self limiting

NSAIDS for pain
Beta blockers for symptom relief

Question 16

What is thyroid storm?

Answer 16

AKA thyrotoxic crisis

More severe presentation of hyperthyroidism with pyrexia, tachycardia and delirium

Question 17

Treatment for hyperthyroidism

Answer 17

Carbimazole
Propylthiouracil
Radioactive Iodine
Beta blockers
Surgery + levothyroxine

Question 18

What drugs can cause hypothyroidsim?

Answer 18

Lithium

Amiaodarone (can also cause thyrotoxicosis)

Question 19

What is secondary hypothyroidism?

Answer 19

Pituitary fails to produce enough TSH

Often associated with lack of ACTH

Question 20

Causes of seconday hypothyroidism

Answer 20

Tumours
Infection
Vascular (e.g. Sheehan Syndrome)
Radiation

Question 21

Features of hypothyroidism

Answer 21

Weight gain
Constipation
Course hair / hair loss
Dry skin
Fatigue
Fluid retention
Heavy / irregular periods

Question 22

Which cells produce PTH?

Answer 22

Chief Cells produce PTH in response to hypoalcaemia

Question 23

How does PTH raise blood calcium? (4)

Answer 23

Increasing osteoclast activity in bones (reabsorbing calcium from bones)
Increasing calcium absorption from the gut
Increasing calcium absorption from the kidneys
Increasing vitamin D activity

Question 24

Symptoms of hypercalcaemia

Answer 24

kidney STONES
painful BONES
abdominal GROANS (constipation, nausea, vomiting)
Psychiatric MOANS (fatigue, depression, psychosis)

Question 25

What is the cause and effect of primary hyperparathyroidism?

Answer 25

Caused by tumour of the parathyroid glands
Leads to hypercalcaemia

Treated surgically

Question 26

What is the cause and effect of secondary hyperparathyroidism?

Answer 26

Caused by vitamin D insufficiency or chronic renal failure

Leads to:
low absorption of calcium from the intestines, kidneys and bones
Hypocalcaemia
Hyperplasia of parathyroid glands

Treated with viamin D or renal transplant

Question 27

What is tertiary hyperparathyroidism?

Answer 27

Happens when secondary hyperparathyroidism continues long term and there is hyperplasia of the glands
The cause is treated and the high level of PTH leads to high absorption of calcium

Treated surgically