Question

Exophthalmic goitre is caused due to
a. Hypersecretion of thyrocalcitonin
b. Hyposecretion of thyrocalcitonin
c. Hypersecretion of thyroxine
d. Hyposecretion of thyroxine

Answer 1

Hint: Exophthalmic goitre is a disease in which enlargement of thyroid gland occurs, increase in basal metabolic rate, protrusion of the eyeballs and weight loss appears. Exophthalmic goiter is also known as Graves disease or toxic diffuse goiter.

Complete answer:
Exophthalmic goitre is an endocrine disorder that causes excess thyroid hormone action in tissue which is termed as thyrotoxicosis and also results in hyperthyroidism which means excess secretion of thyroid hormone or hypersecretion of thyroxine. The thyroid gland becomes larger than its normal size and also causes exophthalmos which result in protrusion of eyes that result in double vision and sometimes loss of vision. Exophthalmic goitre is an autoimmune disease of the body as antibodies are produced by our body. It occurs to young to middle age humans.

Calcitonin hormone is also secreted by thyroid gland when there is an increase in blood calcium level in the body. This hormone results in temporary reduction in activity and number of osteoclasts which help in controlling blood calcium level of the body. Hypersecretion of thyrocalcitonin causes calcium tetany disease. The reduction in secretion of calcitonin hormone in the thyroid gland causes high blood calcium level in the body and uncontrolled muscle movements.

Hyposecretion of thyroxine causes weight gain, hair loss, lowered body temperature, puffed skin and decrease in pulse rate of the body. This disease is known as Myxedema.

Hence, The correct answer is option (C).

Note: There is no treatment for the Exophthalmic goitre till now. It is treated with the help of radioactive iodine, antithyroid drug or if the situation becomes critical the thyroid is removed surgically.