QuestionSBA
QuestionChoice
This describes Grave's disease, which is an autoimmune disease affecting the thyroid gland.  In Grave's disease, autoantibodies activate TSH receptors and cause excessive thyroid hormone synthesis and secretion.
10001996
e
Autoimmune activation of thyroid tissue leads to excessive thyroid hormone synthesis
QuestionChoice
The Wolff-Chaikoff effect is an autoregulatory phenomenon where a high intake of iodine leads to a decrease in thyroid hormone synthesis. This occurs as a feedback mechanism to prevent the overproduction of thyroid hormones. This effect is considered to be transient.
10001992
a
A decrease in thyroid hormone synthesis that occurs in response to high levels of iodine
QuestionChoice
This does not correctly describe the Wolff-Chaikoff effect: it is, in fact, the opposite of the correct description. In the Wolff-Chaikoff effect, high levels of iodine intake acutely suppress thyroid hormone production.
10001993
b
An increase in thyroid hormone synthesis that occurs in response to low levels of iodine
QuestionChoice
This describes Hashimoto's thyroiditis, which is an autoimmune disease affecting the thyroid gland. Here, antithyroid antibodies attack the thyroid tissue, causing fibrosis and insufficient thyroid hormone production.
10001995
d
Autoimmune attack of the thyroid gland causes deficient thyroid hormone production
QuestionChoice
This describes the Jod-Basedow phenomenon: in individuals with iodine-deficient hypothyroidism, increased iodine exposure leads to excessive thyroid hormone synthesis. This does not occur in euthyroid individuals. The Jod-Dasedow effect produces iodine-induced hyperthyroidism. In the Wolff-Chaikoff effect, we see iodine-induced hypothyroidism.
10001994
c
Excessive thyroid hormone synthesis as a result of increased iodine exposure
Concept
Chapter
2693
3959
Hyperthyroidism
Topic
133
Endocrinology
12945
Which of the following options best describes the Wolff-Chaikoff effect?
a