Careful history taking and examination are required to
recognise characteristic patterns of disease. Thyroid disease and
diabetes mellitus are common and frequently familial; establishing
a detailed family history is therefore important. Some less common
endocrine disorders (such as multiple endocrine neoplasia) show
an autosomal dominant pattern of inheritance.
The thyroid is a butterfly-shaped gland that lies inferior to the
cricoid cartilage, approximately 4 cm below the superior notch
of the thyroid cartilage (Fig. 10.1A). The normal thyroid has a
volume of <20 mL and is palpable in about 50% of women and
25% of men. It is comprised of a central isthmus approximately
1.5 cm wide, covering the second to fourth tracheal rings, and
two lateral lobes that are usually no larger than the distal phalanx
of the patient’s thumb. The gland may extend into the superior
mediastinum and can be partly or entirely retrosternal. Rarely, it
can be located higher in the neck along the line of the thyroglossal
duct, an embryological remnant of the descent of the thyroid
from the base of the tongue to its final position. Thyroglossal
cysts can also arise from the thyroglossal duct; they often occur
at the level of the hyoid bone (Fig. 10.1A) and characteristically
move upwards on tongue protrusion. The thyroid is attached to
the pretracheal fascia and thus moves superiorly on swallowing
Thyrotoxicosis is a clinical state of increased metabolism caused
by elevated circulating levels of thyroid hormones. Graves’ disease
is the most common cause (Fig. 10.2 and Box 10.2). It is an
autoimmune disease with a familial component and is 5–10
times more common in women, usually presenting between 30
and 50 years of age. Other causes include toxic multinodular
goitre, solitary toxic nodule, thyroiditis and excessive thyroid
Hypothyroidism is caused by reduced levels of thyroid
hormones, usually due to autoimmune Hashimoto’s thyroiditis,
and affects women approximately six times more commonly
than men. Most other causes are iatrogenic and include previous
radioiodine therapy or surgery for Graves’ disease.
Goitre is enlargement of the thyroid gland (Fig. 10.3). It is not
necessarily associated with thyroid dysfunction and most patients
occult nodules; thus many are found incidentally on neck or
Neck pain is uncommon in thyroid disease and, if sudden in
onset and associated with thyroid enlargement, may represent
with goitre are euthyroid. Large or retrosternal goitres may cause
compressive symptoms, including stridor, breathlessness or
Thyroid nodules may be solitary (Fig. 10.3C) or may present as
a dominant nodule within a multinodular gland. Palpable nodules
(usually >2 cm in diameter) occur in up to 5% of women and
less commonly in men, although up to 50% of patients have
Past medical, drug, family and social history
• prior neck irradiation (risk factor for thyroid malignancy)
• recent pregnancy (postpartum thyroiditis usually occurs in
• drug therapy: antithyroid drugs or radioiodine therapy;
amiodarone and lithium can cause thyroid dysfunction
• family history of thyroid or other autoimmune disease
• residence in an area of iodine deficiency, such as the
Andes, Himalayas, Central Africa: can cause goitre and,
• smoking (increases the risk of Graves’ ophthalmopathy).
bleeding into an existing thyroid nodule. Pain can also occur in
viral subacute (de Quervain’s) thyroiditis.
History suggesting hyperthyroidism
• tremor, heat intolerance, excessive sweating (hyperhidrosis)
• pruritus (itch), onycholysis (loosening of the nails from the
• irritability, anxiety, emotional lability
• dyspnoea, palpitations, ankle swelling
• weight loss, hyperphagia, faecal frequency, diarrhoea
• proximal muscle weakness (difficulty rising from sitting or
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