hyperthyroidism

Etiologies-hyperthyroidism

Clinical manifestations

• Restlessness, sweating, tremor, moist warm skin, fine hair, tachycardia,
• AF, weight loss, ↑ frequency of stools, menstrual irregularities, hyperreflexia, osteoporosis, stare and lid lag (due to sympathetic overactivity)
• Apathetic thyrotoxicosis: seen in elderly who can present with lethargy as only sx

Laboratory testing

• ↑ free T4 and total T3; ↓ TSH (except in TSH-secreting tumors)
• Gold standard: I131 uptake and scan
• RAIU scan is useful study to differentiate causes (see table on page 7-3); cannot do if recent IV contrast or amio load b/c iodine blocks uptake, so ✓ autoantibodies instead
• No need to ✓ for autoantibodies except in pregnancy (to assess risk of fetal Graves’)
• May see hypercalciuria ± hypercalcemia, ↑ Aϕ, anemia

Graves’ disease

Thyroiditis

[[Thyroiditis]]

Treatment-hyperthyroidism (Thyroid 2016;26:1343; JCEM 2020;105:3704)

Subclinical hyperthyroidism

Subclinical hyperthyroidism (NEJM 2018;378:2411)

• Mild ↓ TSH and normal free T4 with only subtle or no sx
• ~15% → overt hyperthyroidism in 2 y; ↑ risk of AF, CHD, fracture (JAMA 2015;313:2055)
• Rx controversial: consider if TSH <0.1 mU/L and ↑ risk for CV disease or osteopenic Thyroid storm (extremely rare; JCEM 2015;2:451)

qv: - 👉 hyperpituitary syndromes