Hyperthyroidism

Question 1

Hyperthyroidism Hormones

Answer 1

• Thyrotropin releasing hormone from the hypothalamus
• TSH from anterior pituitary
• More T4 than T3 produced, T4 is inactive and converted to T3 in liver and kidney

Question 2

Hyperthyroidism Aetiology

Answer 2

• Graves’ disease is most common cause
• Toxic nodular goitre more common in people aged over 60
• Drug induced, adenomas and resistance are also causes

Question 3

Hyperthyroidism RFs

Answer 3

• FHx
• High iodine intake
• Smoking
• Trauma …

Question 4

Hyperthyroidism Presentation

Answer 4

Symptoms
-WL, weight gain, increase or decrease in appetite, irritability, weakness and fatigue, diarrhoea, sweating, tremor, heat intolerance, oligomenorrhoea
Signs
-Palmar erythema, sweaty and warm palms, fine tremor, fine tremor, tachycardia, hair thinning or diffuse alopecia, urticaria, pruritus, brisk reflexes

Question 5

Hyperthyroidism Thyrotoxic Crisis or Storm

Answer 5

• Either ineffectively treatment or undiagnosed cases
• Rare condition
• Hyperthermia, mental disturbance, hyperpyrexia, tachycardia, N/V/D, abdo pain
• Usually associated with precipitating events, like withdrawal, radio-iodine therapy, infection, surgery
• Management is IV fluids, BBs, antithyroid drugs (e.g. carbimazole) and steroids
• Look for presence of Addisons
• High mortality

Question 6

Hyperthyroidism Graves’ Disease

Answer 6

• Autoimmune mediated by antibodies that stimulate TSH receptor, excess secretion and hyperplasia leading to goitre
• Eye changes
• Pretibial myxoedema

Question 7

Hyperthyroidism Other Types

Answer 7

• De Quervain’s
• Toxic nodular goitre
• Solitary thyroid nodule
• Self medication

Question 8

Hyperthyroidism Dx

Answer 8

Phaeochromocytoma or other causes of weight loss

Question 9

Hyperthyroidism Ix

Answer 9

• TFTs
• Autoantibodies; most commonly seen in Graves’, can differentiate between toxic nodular
• Imaging; thyroid USS, uptake scan, inflammatory markers
• Inflammatory markers; CRP and ESR often raised

Question 10

Hyperthyroidism Management

Answer 10

• Refer to specialist
• BBs can be used for rapid symptom control whilst waiting for thyroid function to normalise
• Three definitive treatments

Antithyroid drugs

• Carbimazole or propylthiouracil
• May take 2-3 weeks to work
• Two methods; block and replace or dose titration (just using drugs), both methods equally affected
• Once euthyroid, titrate dose down to find lowest dose
• Sore throat could be a sign of myelosuppression, need FBC if they get a sore throat

Radio-iodine
-Relapsed Graves’, poor compliance, toxic nodular

Surgery is used infrequently