Unusual types of hyperthyroidism

Hyperthyroidism is a common endocrine disease, characterized by elevated concentrations of circulating thyroid hormones and distinctive symptoms and signs. Over ninety per cent of patients with hyperthyroidism can be classified as having either Graves' disease (diffuse toxic goitre), toxic adenoma (autonomous or 'hot' nodule), or toxic multinodular goitre (Hoffenberg, 1974). The aetiology, pathophysiology, diagnosis, and treatment of these common entities are discussed elsewhere in this symposium. The purpose of this section is to describe the unusual types of thyrotoxicosis, with special emphasis on the more recent literature, especially that not covered by a similar report from this unit which appeared in 1973 (Hamilton and Maloof, 1973).