|Hyperthyroidism (ReelDx)||Etiology: Grave’s disease (autoimmune). Toxic adenoma, thyroiditis, pregnancy, amiodarone
Presentation: Heat intolerance, palpitations, sweating, weight loss, tremor, anxiety, tachycardia
Antithyroid drugs during pregnancy — Propylthiouracil used to be the drug of choice during pregnancy because it causes less severe birth defects than methimazole. But experts now recommend that propylthiouracil be given during the first trimester only. This is because there have been rare cases of liver damage in people taking propylthiouracil. After the first trimester, women should switch to methimazole for the rest of the pregnancy.
For women who are nursing, methimazole is probably a better choice than propylthiouracil (to avoid liver side effects).
|Hypothyroidism||28-year-old woman with tender thyroid, hypothyroidism, elevated antimicrosomal antibodies, increased antithyroglobulin antibodies
Etiology: Hashimoto’s (chronic lymphocytic/autoimmune), previous thyroidectomy/iodine ablation, congenital
Labs: TSH- elevated in primary disease. Low T4 (↑ TSH and ↓ Free T4)
Treatment: Levothyroxine. Follow up with serial TSH monitoring
|Thyroiditis||Painful vs. Painless may be hypo or hyperthyroid
|When a patient is suspected of having an underlying thyroid condition, there is a stepwise approach to ordering thyroid function tests. The initial screening test of choice is the measurement of thyroid stimulating hormone or TSH. Depending on the value determined, measurements of thyroid hormones (serum free T3 and free T4) may be taken, with the addition of a total T4 measurement to provide further evidence towards the underlying cause. Regardless of etiology, screening tests are not always reliable in a severely ill inpatient population, and special circumstances, like pregnancy, may alter the measured value of these tests.|
|The parathyroid gland is a series of four small glands located in the neck on the rear surface of the thyroid gland. It serves primarily in calcium homeostasis and has a blood calcium sensor that detects when blood calcium levels are abnormally low. It responds by releasing parathyroid hormone (PTH) which stimulates osteoclasts into action. Osteoclasts resorb bone and release a large amount of calcium. This calcium enters the blood and results in increased blood calcium levels. PTH can also activate vitamin D by promoting the activity of an enzyme that converts inactive vitamin D to active vitamin D|
|The thyroid gland is a large endocrine gland that is located in the neck. It releases T3 and T4 hormones, which help the body regulate metabolism. T3 and T4 stand for triiodothyronine (T3) and thyroxine, which can sometimes be referred to as tetraiodothyronine (T4). In addition, the thyroid gland has a blood calcium sensor that helps it detect when blood calcium levels are elevated, to which it responds. The thyroid gland releases calcitonin, which builds bone, resulting in an absorption of calcium from the bloodstream. Osteoblasts are the cells responsible for bone formation.|