Hashimoto thyroiditis

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• Thyroid Dysfunction

  • Hashimoto thyroiditis

• Postpartum thyroiditis

  • This patient has primary hyperthyroidism (elevated T4, suppressed TSH). In light of her nontender goiter and recent pregnancy, this is consistent with postpartum thyroiditis (PT). PT (by definition occurring <1 year following pregnancy) is similar to silent thyroiditis; both are associated with thyroid peroxidase antibody and are considered variants of chronic lymphocytic (Hashimoto) thyroiditis. Both PT and silent thyroiditis typically have a transient hypothyroid phase before returning to a normal euthyroid state, whereas most patients with classic Hashimoto thyroiditis have residual hypothyroidism.

• Subclinical hypothyroidism

  • Subclinical hypothyroidism (SCH) is defined as an elevated serum TSH level with a normal free thyroxine. The most common cause is chronic lymphocytic Hashimoto thyroiditis. The decision to treat SCH with levothyroxine depends on the magnitude of TSH elevation, age, presence of goiter, and whether there are symptoms definitely attributable to hypothyroidism. In addition, high circulating levels of anti-thyroid peroxidase (anti-TPO) antibodies (seen in >90% of patients with Hashimoto thyroiditis) are associated with progression to overt hypothyroidism and can identify patients who are likely to benefit from treatment.