Feature Article

Hypothyroidism: how to make the diagnosis and when to treat it

Shananthan Balachandran, DUNCAN J. TOPLISS




Hypothyroidism may be obvious clinically but it has a wide spectrum of severity and can be very subtle. Many people with normal thyroid function may present to their GP with mild symptoms that suggest hypothyroidism; therefore, biochemical confirmation of true hypothyroidism is mandatory. There is no evidence that levothyroxine treatment of suggestive symptoms is beneficial when the thyroid stimulating hormone level is normal.

Key Points

  • Hypothyroidism is a common condition, with most people having subclinical hypothyroidism.
  • The most common cause of hypothyroidism in Australia is autoimmune thyroid disease.
  • A clinical diagnosis of hypothyroidism should be considered in the presence of one or more of its classic symptoms and signs.
  • People with normal thyroid function may complain of mild symptoms that suggest the possibility of hypothyroidism; therefore, biochemical confirmation is mandatory.
  • Synthetic levothyroxine is the best standard replacement therapy for patients with hypothyroidism.