Female/males = 6-9:1; usually over age 40 yr. Associated with other autoimmune diseases including stimulating autoimmune thyroid disease and autoimmune ophthalmoplegia (Ann IM 1978;88:379); Turner's syndrome; Addison's disease; dermatitis herpetiformis (Ann IM 1985;102:194)

Sx:Hypothyroidism; rarely thyrotoxicosis; goiter; but generally few sx, unlike other thyroiditis; very rarely can be painful (Ann IM 1986;104:355)

Si:As above; nontender gland

Half proceed to myxedema over months to years

Myxedema

r/o much rarer Riedel's struma (fibrosis, increasing mass); postpartum thyroiditis, usually transiently toxic then hypothyroid, then return to normal. And postpartum 2 wk-4 mo, perhaps due to peridelivery immunologic changes (Ann IM 1977;87:154)

Lab:

Chem:TSH elevated as become hypothyroid

Hem:ESR minimally elevated

Path:Thyroid bx shows lymphocytic infiltrate, if done; not necessary

Serol:Elevated antibodies against thyroperoxidase; or antithyroid microsomal antibodies, more specif and more sens (95%) than antithyroglobulin antibodies (60%) (J Lab Clin Med 1979;93:1035)

Xray:Thyroid ¹³¹I, ¹²³I, or technetium scan shows no, or patchy uptake; RAIU usually low, often 0

Rx:None, if radioactive iodine uptake is low, until myxedematous; if RAIU is high, may have an organification defect from the autoimmune disease, or may have coincident Graves' and need rx for that (Nejm 1975;293:624)