ABSTRACT
Acquired hypothyroidism in the developed world is primarily caused by autoimmune thyroid disease. It is the leading cause of thyroid disorders in the pediatric population in the US. Subacute thyroiditis presents with a tender, enlarged thyroid gland, likely due to viral mediated inflammation. Both iodine deficiency and excess can result in hypothyroidism. Acquired hypothyroidism related to iatrogenic causes includes hypothyroidism after complete thyroidectomy or hemithyroidectomy for either thyroid nodules, thyroid cancer, or Graves’ disease. The recommended primary evaluation for acquired primary hypothyroidism is the measurement of a serum thyroid stimulating hormone (TSH). In secondary and tertiary acquired hypothyroidism, the preferred screening evaluation is a direct measurement of free thyroxine as well as the TSH. Treatment of acquired primary hypothyroidism may include observation in cases of subclinical disease, typically when the TSH is less than 10 mIU/mL. In cases of overt hypothyroidism or TSH greater than 10 mIU/mL, thyroid hormone replacement with levothyroxine is indicated as the standard of care.
