Thyrotoxicosis or hyperthyroidism

Hyperthyroidism, or thyrotoxicosis, refers to thyroid overactivity of any cause. Diagnosis is often clinical, but antibody testing may help identify the cause.

Has the patient lost or gained any weight unintentionally? 

Many patients with hyperthyroidism will lose weight due to increased metabolic rate, though some will gain it due to increased appetite.

Has the patient's appetite increased? 

Increased appetite with weight loss is a classic presentation of hyperthyroidism.

Does the patient complain of diarrhoea or a change in bowel habit? 

Increased passage of stools and diarrhoea may occur with any cause of hyperthyroidism. Coeliac disease may also be associated with auto-immune thyroid disease, and may also present with a change in bowel habit and weight loss.

Do they feel anxious or more irritable than usual? 

Anxiety and irritability are common features of thyrotoxicosis of any cause.

Has the patient noticed a change in their energy? 

Many patients with hyperthyroidism have an abundance of energy. Some may also complain of tiredness, as they are unable to relax and sleep.

Others, particularly older patients, may have apathetic thyrotoxicosis in which their energy is paradoxically low.

Is the patient sleeping normally or are they more tired than usual? 

Many patients with hyperthyroidism will be unable to sleep well as they cannot relax despite feeling physically exhausted.

Does the patient feel hot or flushed?

Heat intolerance is typical with hyperthyroidism.

Premature ovarian failure may also be associated with auto-immune thyroid disease and may also present with oligomenorrhoea and flushes.

Has there been a change in menstrual cycle? 

Oligomenorrhoea, scanty periods and amenorrhoea may all occur.

Is there any chance the patient could be pregnant? 

The symptoms of thyrotoxicosis may mimic those of pregnancy.

Early foetal loss or miscarriage is more common in women with thyrotoxicosis.

Pregnancy may also cause transient thyrotoxicosis due to stimulation of the TSH receptor by high chorionic gonadotropin (hCG) levels.

Radioactive iodine is absolutely contraindicated in pregnant women.

Does the patient feel tremulous or have they developed an overt shake? 

Tremor is common with thyrotoxicosis of any cause.

Has the patient developed any cardiac or respiratory symptoms? 

Ask whether the patient has experienced palpitations, or a racing or irregular heart beat which might suggest tachycardia or atrial fibrillation.

Exertional chest pain would suggest cardiac ischaemia, and breathlessness would suggest thyrotoxic cardiomyopathy or pulmonary embolism.

Does the patient complain of any changes to their skin or hair? 

Increased pigmentation may indicate associated Addison's disease.

Some patients develop generalised alopecia with thyrotoxicosis though this may also occur in hypothyroidism.

Has there been any obvious neck swelling or pain? 

Painful diffuse neck swelling is suggestive of thyroiditis which can cause acute thyrotoxicosis.

Discomfort from a diffusely enlarged gland is more common with Graves' thyrotoxicosis.

Painless, long standing nodularity of the neck is more suggestive of a multinodular goitre, and a single nodule suggests a follicular adenoma as the cause of thyrotoxicosis.

Sudden swelling is most common with a cyst, which is not usually associated with thyroid overactivity. Sudden painful swelling suggests a bleed into an existing  nodule.

A short history of thyroid swelling should alert to the possibility of thyroid cancer and demands ultrasound and fine needle aspiration assessment, though this is not typical with thyrotoxicosis.

Long standing painless thyroid swelling, with some fluctuation in size is more likely to represent a multinodular goitre.

Has the patient noticed any changes in their eyes?

Ask specifically whether their eyes have been feeling gritty or dry, as though there is something stuck in them. Ask whether they have looked red or puffy at times, or whether their appearance has changed. Also ask whether they have developed double vision in certain directions or when tired. Any of these symptoms suggests that Graves' disease is the underlying cause of thyrotoxicosis.

A startled appearance, with slightly wider eyes than usual, may occur with any cause of thyrotoxicosis.

Is there any family or personal history of thyroid dysfunction, pernicious anaemia, vitiligo, Addison's disease, alopecia, diabetes or coeliac disease?

Any of these may be associated with auto-immune thyroid dysfunction.

Has there been any recent intercurrent illness, for example a viral respiratory tract infection?

Thyroiditis typically follows a viral illness, though this is frequently unrecognised.

Does the patient smoke?

Smoking increases the risk and severity of ophthalmopathy.

Is there any family history of thyroid swelling or neck surgery?

Thyroid cancer, multinodular goitres and auto-immune thyroid disease may all occur more frequently within family members.

Where is the family from originally?

Multinodular goitre and endemic goitres are particularly common in certain geographical regions with iodine deficiency.