Hypothyroidism Flashcards
What is hypothyroidism?
An insufficiency of T3 and T4
What is the universal cause of primary hypothyroidism?
Thyroid behaving abnormally and producing inadequate levels of thyroid hormones
What is the universal cause of secondary hypothyroidism?
The pituitary behaves abnormally and produces inadequate TSH
What is the most common cause of hypothyroidism in the developed world?
Hashimoto’s thyroiditis
What is the most common cause of hypothyroidism in the developing world?
Iodine deficiency
What is Hashimoto’s thyroiditis?
An autoimmune condition causing inflammation of the thyroid gland
What antibodies are associated with Hashimoto’s thyroiditis?
Anti-thyroid peroxidase (anti-TPO)
Anti-thyroglobulin (anti-Tg)
What 4 treatments of hyperthyroidism can cause hypothyroidism?
Carbimazole
Propylthiouracil
Radioactive iodine
Surgery
What does lithium do in the thyroid gland?
What can this cause?
Inhibits the production of thyroid hormones
Can cause a goitre and hypothyroidism
What drug interferes with thyroid hormone production and metabolism?
Amiodarone
What is hypopituitarism?
A lack of pituitary hormones that is associated with secondary hypothyroidism
Name some causes of hypopituitarism?
Tumours - pituitary adenomas
Pituitary surgery
Radiotherapy
Sheehan’s syndrome
Trauma
What are the clinical presentation of hypothyroidism?
Weight gain
Fatigue
Dry skin
Course hair / hair loss
Fluid retention / oedema
Heavy / irregular periods
Constipation
What does iodine deficiency cause?
Goitre
What is the first-line treatment of hypothyroidism?
Levothyroxine
What is levothyroxine?
A synthetic version of T4 that metabolises to T3 in the body
