A goitre is an enlargement of the thyroid gland. It may be congenital or acquired.
A goitre is an enlargement of the thyroid gland. It may be congenital or acquired. Thyroid function may be normal (euthyroid), underactive (hypothyroid), or overactive (hyperthyroidism). Enlargement is usually 2 to the increased pituitary secretion of TSH, but may, in certain cases, be due to an infiltrative process that may be either inflammatory or neoplastic.
The commonest causes of congenital goitre are due to the transplacental transmission of factors that interfere with foetal thyroid function from the mother to the foetus:
- maternal antithyroid drugs;
- maternal iodine exposure;
- maternal hyperthyroidism (Graves’s disease).
Other rare causes include:
- thyroid teratoma;
- endemic iodine deficiency;
- thyroid hormone biosynthetic defects (e.g. Pendred syndrome).
- Simple (colloid) goitre.
- Multinodular goitre.
- Acute thyroiditis.
- Graves’s disease.
- Anti-thyroid chemical exposure: iodine intoxication.
- Anti-thyroid drugs: lithium, amiodarone.
Simple (colloid) goitre
This is a euthyroid, non-toxic goitre of unknown cause. It is not associated with a disturbance of thyroid function and is not associated with either inflammation or neoplasia. Thyroid function tests and radioisotope scans are normal. It is most common in girls during or around the peripubertal years. Treatment is not needed, although follow-up is recommended.
- A firm goitre with single or multiple palpable nodules.
Thyroid function studies usually normal, although TSH and anti-thyroid antibody titres may be elevated. Abnormalities on thyroid US and areas of reduced uptake on radioisotope scanning may be seen.