Hyperthyroidism

Question 1

Causes

Answer 1

G – Graves’ disease
I – Inflammation (thyroiditis)
S – Solitary toxic thyroid nodule
T – Toxic multinodular goitre

Question 2

Thyroiditis?

Answer 2

often causes an initial period of hyperthyroidism, followed by under-activity of the thyroid gland (hypothyroidism). The causes of thyroiditis include:

De Quervain’s thyroiditis
Hashimoto’s thyroiditis
Postpartum thyroiditis
Drug-induced thyroiditis

Question 3

Presentation

Answer 3

Anxiety and irritability
Sweating and heat intolerance
Tachycardia
Weight loss
Fatigue
Insomnia
Frequent loose stools
Sexual dysfunction
Brisk reflexes on examination

Question 4

Graves’ disease has specific features relating to the presence of TSH receptor antibodies:

Answer 4

Diffuse goitre (without nodules)
Graves’ eye disease, including exophthalmos
Pretibial myxoedema
Thyroid acropachy (hand swelling and finger clubbing)

Question 5

Solitary Toxic Thyroid Nodule

Answer 5

A solitary toxic thyroid nodule is where a single abnormal thyroid nodule acts alone to release excessive thyroid hormone. The nodules are usually benign adenomas. Treatment involves surgical removal of the nodule.

Question 6

De Quervain’s Thyroiditis

Answer 6

De Quervain’s thyroiditis, also known as subacute thyroiditis, is a condition causing temporary inflammation of the thyroid gland. There are three phases:

Thyrotoxicosis
Hypothyroidism
Return to normal

The initial thyrotoxic phase involves:

Excessive thyroid hormones
Thyroid swelling and tenderness
Flu-like illness (fever, aches and fatigue)
Raised inflammatory markers (CRP and ESR)

It is a self-limiting condition, and supportive treatment is usually all that is necessary. This may involve:

NSAIDs for symptoms of pain and inflammation
Beta blockers for the symptoms of hyperthyroidism
Levothyroxine for the symptoms of hypothyroidism

Question 7

Thyroid Storm

Answer 7

Thyroid storm is a rare presentation of hyperthyroidism. It is also known as thyrotoxic crisis. It is a rare and more severe presentation of hyperthyroidism with fever, tachycardia and delirium. It can be life-threatening and requires admission for monitoring. It is treated the same way as any other presentation of thyrotoxicosis, although they may need additional supportive care with fluid resuscitation, anti-arrhythmic medication and beta blockers.

Question 8

Management

Answer 8

Carbimazole is the first-line anti-thyroid drug, usually taken for 12 to 18 months. Once the patient has normal thyroid hormone levels (usually within 4-8 weeks), they continue on maintenance carbimazole and either:

The carbimazole dose is titrated to maintain normal levels (known as titration-block)
A higher dose blocks all production, and levothyroxine is added and titrated to effect (known as block and replace)

Propylthiouracil is the second-line anti-thyroid drug. It is used in a similar way to carbimazole. There is a small risk of severe liver reactions, including death, which is why carbimazole is preferred.