Thyroid Disease

Question 1

What are some causes of hypothyroidism?

Answer 1

• Hashimoto’s thyroiditis
• Subacute thyroiditis (hyper then hypo)
• Iodine deficiency
• Treatment for hyperthyroidism
• Medications eg, Lithium or amiodarone
• Postpartum hypothyroidism
• Secondary causes eg, hypopituitarism

Question 2

Explain features of Hashimoto’s thyroiditis

Answer 2

• Autoimmune inflammation caused by anti-thyroid peroxidase antibodies (and anti-thyroglobullin antibodies)
• Associated with Addison’s disease, pernicious anaemia, T1DM and coeliac’s disease

Question 3

Explain the presentation of Hypothyroidism

Answer 3

• Weight gain
• Macroglossia
• Cold intolerence
• Dry skin
• Coarse hair/ hair loss
• Fatigue
• Fluid retention
• Oedema,
• Plural effusions
• Ascites
• Amenorrhoea
• Constipation
• Decreased tendon reflexes
• Carpal tunnel syndrome
• Cerebellar ataxia
• Bradycardia
• Cardiomegaly
• Peripheral neuropathy

Question 4

What are the investigations for Hypothyroidism. What are he differnet results for primary/secondary

Answer 4

• TSH, T3 and T4 levels
• In primary hypothyroidism there is high TSH and low T3/T4
• In secondary hypothyroidism there is low TSH and low T3/4

Question 5

What is the treatment for hypothyroidism and its side effects

Answer 5

Levothyroxine (metabolised to T3) titrated up (measure monthly TSHs). Therapeutic goal is normalisation of TSH
Side effects: Hyperthyroidism, reduced bone mineral density, worsening of angina, atrial fibrillation

Question 6

What are the causes of hyperthyroidism?

Answer 6

• Graves Disease (TSH autoantibodies mimic TSH)
• Toxic multinodular goitre (nodules act independantly)
• Solitaty toxic thyroid nodule (usually adenoma)
• De Quervain’s thyroiditis

Question 7

What is the difference between primary and secondary hyperthyroidism

Answer 7

• Priamry is caused by thyroid pathology
• Secondary is caused by a pituitary or hypothalamic pathology

Question 8

What are the symptoms of hyperthyroidism?

Answer 8

• Symptoms of hyperthyroidism
  Anxiety and irritability,
  Sweating and heat intolerance,
  Tachycardia (AF),
  Fine tremor
  Weight loss,
  Thyroid bruit
  Fatigue,
  Frequent loose stools
  Sexual dysfunction
• Symptoms of Graves
  Diffuse goitre
  Thyroid eye disease - Lid lag, lid retraction, exophthalmoses
  Pretibial myxoedema
  Thyroid acropachy

Question 9

What is De quervain’s thyroiditis?

Answer 9

Viral infection which causes fever, neck pain, tenderness, dysphagia and hyperthyroidism (followed by hypothyroidism)
Self limiting (treated with NSAID and BBs for hyper symptoms)

Question 10

What is thyroid storm/ thyrotoxic crisis?

Answer 10

• Acute severe presentationdue to excess thyroid hormone.
• Usually precipitated by surgery, trauma or infection.

Question 11

Explain the presentation of thyroid storm

Answer 11

Presents with pyrexia, tachycardia, nausea and vomiting, confusion and delirium
Requires admission for monitoring

Question 12

Explain the management of thyroid storm

Answer 12

• IV propranolol
• IV Digoxin
• Propylthiouracil via NG tube followed by Lugol’s iodine 6 hours later
• Prednisolone/hydrocortisone

Question 13

What is the management of hyperthyroidism?

Answer 13

Either titration block or block and replace
Carbimazole (risk of agranulocytosis)
Propylthiouracil (small risk of severe hepatic reactions) Used in first trimester of pregnancy
Radioactive iodine (may result in hypothyroidism)
Beta blockers for symptoms (propranolol)

Question 14

WHat are the test results for subclinical hyper/hypo-thyroidism?

Answer 14

Hyper - Low TSH and High T3/T4
Hypo - High TSH but normal T3/4

Question 15

What is sick euthyroid syndrome?

Answer 15

Low TSH and low T4 (common in hospitals)

Question 16

What are some causes of a smooth goiter?

Answer 16

• Graves disease,
• Hashimoto’s disease,
• Drugs
• Iodine def/excess
• De Quervain’s thyroiditis (painful)
• Infiltration, eg, sarcoid/haemochromatosis

Question 17

What are some causes of a nodular goitre?

Answer 17

• Toxic solitary adenoma
• Non-functional thyroid adenoma
• Multinodular goitre
• Thyroid cysts
• Cancer

Question 18

How can you tell the difference between a thyroid cancer or a thyroglossal cyst?

Answer 18

Thyroid cyst will move up when you stick out your tongue but a thyroid nodule will move up when you swallow.

Thyroglossal cyst may also move when swallowing.

Question 19

What is the first line investigation for a thyroid mass?

Answer 19

Ultrasound

Question 20

What is the pathophysiology of thyroid eye disease?

Answer 20

Autoimmune response against an autoantigen which is thought to cause retro-orbital inflammation. The inflammation causes glycosaminoglycan and collagen deposition in muscles.

Question 21

What are the features of thyroid eye disease

Answer 21

Main modifiable risk factor is smoking.
Exophthalmos
Conjunctival oedema
Optic disc swelling
Ophthalmoplegia
Inability to close eyelids which can cause eyes to become sore and dry

Question 22

What is the management of thyroid eye disease?

Answer 22

Topical lubricants
Steroids
Radiotherapy
Surgery

Question 23

When should a patient with thyroid eye disease get an urgent ophthalmology review?

Answer 23

If they experience any of the following:
Unexplained deterioration in vision
Change in colour vision
History of globe subluxation
Obvious corneal opacification
Cornea still visible when eyes are closes
Optic disc swelling