Hypothyroidism is an endocrine disorder that results from thyroid hormonal deficiency. In the U.S. and other regions that have sufficient iodine consumption, autoimmune thyroid or the Hashimoto disease, normally causes hypothyroidism, while worldwide, iodine deficiency is the leading cause.
Pathophysiology
Hypothyroidism can be caused by malfunctioning of the hypothalamus, thyroid, or pituitary gland, as all of these result from the same “negative feedback mechanism” (McCann, 2011, p. 496). Despite belonging to the same mechanism the hypothalamus malfunction rarely causes hypothyroidism, and when it does, it is called ‘secondary hypothyroidism’. While the malfunction of the gland is referred to as ‘primary ...