**2.2. Epidemiology**

160 Thyroid Hormone

A. Thyroid hormone excess with hyperthyroidism a. Primary Hyperthyroidism

i. Graves' Disease

vi. Struma Ovarii

B. Thyroid hormone excess without hyperthyroidism a. Throiditis: subacute, silent

**Symptoms Signs**

Heat Intolerance Fine tremor

Palpitation, Nervousness Warm moist skin, Goiter Fatigue, lethargy Proximal Myopathy Dyspnoea Hyperreflexia Weight loss despite polyphagia Lid lag, Lid tremors Hyperdefecation, Polyuria Gynaecomastia Oligomenorrhoea Loss of libido

Infiltrative orbitopathy is an unique manifestation of Graves' disease.

b. Secondary hyperthyroidism

thyroid adenoma

**Table 1.** Causes of thyroid hormone excess

**Table 2.** Common clinical features

**2.1. Historical perspective** 

**2. Graves' disease** 

ii. Toxic Thyroid adenoma iii. Toxic Multinodular Goiter

iv. Metastases from Thyroid carcinoma

i. TSH secreting pituitary tumours ii. Pituitary Thyroid hormone resistance

b. Ingestion of thyroid tissue, thyroid hormone

vii. Iodine ingestion (jod-Basedow phenomenon)

Irritability, Hyperactivity, Dysphoria Tachycardia, Lone Atrial Fibrillation

Diffuse toxic goitre is commonly known as Graves' disease. Classically it is characterized by hyperthyroidism and diffuse goiter. Graves' disease may be associated with an infiltrative orbitopathy and ophthalmopathy and less commonly with an infiltrative dermopathy.

Robert James Graves, an Irish physician, first described 3 females with this disease in 18351 and for his contribution, this disease is known as Graves' disease in most part of the world. Although a similar syndrome was described by Caleb Hiller Parry, a physician from Bath,

v. Mutations of TSH receptor, Gsα (Mc Cune Albright Syndrome)

c. Thyroid gland destruction by amiodarone, radiotherapy, infarction in

Graves' disease is the most common cause of thyrotoxicosis and it accounts for 60-80% cases of thyrotoxicosis. Prevalence of Graves' disease varies with the degree of iodine sufficiency, and it is the most common cause of thyrotoxicosis in iodine sufficient countries.4 High dietary iodine intake is associated with an increased prevalence of Graves' disease. Prevalence of Graves' disease is about 0.4% in USA,5 0.6% in Italy,6 and 1.1% in UK.7 A recent meta-analysis of various studies showed that prevalence of the Graves' disease is about 1% in general population.7 Prevalence of Graves' disease is 1-2% in women, and it is about 10 fold more prevalent in women than men. Peak age of onset of Graves' disease is in fourth to sixth decade of life,8 but it can occur in children and elderly.
