Hypothyroidism Flashcards
What does FT4 stand for?
FT4 stands for free thyroxine, which is the active and unbound form of thyroid hormone thyroxine (T4) circulating in the blood.
What causes hypothyroidism?
Hypothyroidism results from the underproduction and secretion of thyroid hormones by the thyroid gland.
What are common symptoms of hypothyroidism?
Symptoms include fatigue, weight gain, constipation, menstrual irregularities, depression, dry skin, cold intolerance, and reduced body and scalp hair.
What are the complications of hypothyroidism?
Complications include dyslipidaemia, coronary heart disease, heart failure, impaired fertility, pregnancy complications, impaired concentration, and myxoedema coma.
What is primary hypothyroidism?
Primary hypothyroidism occurs due to an issue within the thyroid gland itself, such as iodine deficiency, autoimmune diseases, radiotherapy, or surgery.
What is secondary hypothyroidism?
Secondary hypothyroidism is due to a pituitary or hypothalamic disorder, causing insufficient thyroid-stimulating hormone (TSH) production.
What is overt hypothyroidism?
Overt hypothyroidism is characterized by TSH levels above the reference range and FT4 levels below the reference range.
What is subclinical hypothyroidism?
Subclinical hypothyroidism occurs when TSH levels are above the reference range, but FT4 and FT3 levels are still within normal limits.
How is overt hypothyroidism treated?
Levothyroxine sodium (LT4) is the first-line treatment, aiming to normalize TSH levels. The medication should be taken on an empty stomach.
How is subclinical hypothyroidism managed?
For TSH levels of 10 mIU/L or higher, levothyroxine sodium may be started. For those with TSH between 5-10 mIU/L, consider a 6-month trial of levothyroxine if symptomatic.
How should hypothyroidism in pregnancy be managed?
Refer to an endocrinologist for pregnant women or those planning pregnancy.
Trimester-specific reference ranges should be used for thyroid function tests (TFTs), and levothyroxine sodium treatment may be adjusted.
What should be done postpartum for women treated with levothyroxine during pregnancy?
Postpartum, discuss the adjustment of levothyroxine dose with an endocrinologist, and check TSH levels 6 weeks after delivery.
What is postpartum thyroiditis (PPT)?
PPT is an inflammation of the thyroid following childbirth. It may involve a hypothyroid phase after a transient hyperthyroid phase, and levothyroxine treatment may be needed in some cases.
