Goitre

Define goitre

Abnormal growth of the thyroid gland

What are the 2 main clinical forms of a goitre?

1) Diffuse

2) Nodular

What term is given to a goitre where there is growth of one or both thyroid lobes through the thoracic inlet into the thoracic cavity?

Retrosternal goitre

What is the typical and commonest symptom of tracheal obstruction by a goitre?

Shortness of breath / difficulty breathing

(may also be wheeze, cough and choking sensation)

What are the 3 possible consequences of a goitre on thyroid hormone production?

1) Increased production

2) Decreased production

3) Normal production

What is the commonest cause of a goitre globally?

Iodine deficiency

List the 3 commonest causes of a goitre in iodine replete regions of the world

1) Multinodular goitre

2) Chronic autoimmune thyroiditis

(Hashimoto’s thyroiditis)

3) Graves’ disease

How is the serum TSH level often affected in patients with non-toxic multinodular goitre?

Normal

What is the mechanism of thyroid gland growth and goitre in Graves’ disease?

Stimulation of the TSH receptor by TSH receptor antibodies (TRAb)

Are the majority of patients with a goitre symptomatic or asymptomatic?

Asymptomatic (due to slow growth)

What biochemical state of thyroid function do the majority of patients with a goitre have?

Biochemically euthyroid

What symptom may be caused by recurrent laryngeal nerve compression by a goitre?

Hoarseness of voice (due to vocal cord palsy)

List the 3 commonest causes of a goitre in adults

1) Multinodular goitre

2) Iodine deficiency

3) Autoimmune thyroid disease

Which hormone level should be measured in all patients with a goitre?

Serum TSH level

Which antibodies can be checked in patients with a goitre?

Thyroid peroxidase antibodies

In a patient with a goitre and positive thyroid peroxidase antibodies what is the most likely diagnosis?

Autoimmune thyroiditis (Hashimoto’s thyroiditis)

What important condition should be suspected with rapid growth of the thyroid gland?

Malignancy

What is the approximate risk of thyroid cancer within a multinodular goitre?

3-5%

What is the approximate risk of thyroid cancer within a solitary thyroid nodule?

3-5%

In iodine deficiency an increase in which hormone is the main cause of goitre?

TSH

In chronic autoimmune (Hashimoto’s) thyroiditis an increase in which hormone is the main cause of goitre?

TSH

How may serum TSH levels and size of the goitre correlate?

In larger goitres there is lower serum TSH concentration

In hypothyroid patients with a goitre how does levothyroxine treatment affect goitre size?

Size of goitre may reduce over time however in many the goitre does not completely resolve

Which pulmonary function test is helpful in assessing the presence of tracheal obstruction by a goitre?

Flow-volume loop study

What does the inability to identify the inferior end of the thyroid gland on clinical examination indicate?

Significant retrosternal goitre