Elevated TSH

An increased serum thyroid-stimulating hormone (TSH) concentration above the age-specific reference range (~0.4-5.0 mIU/L).

Causes

• Primary hypothyroidism

  • Hashimoto's thyroiditis

  • Thyroid gland destruction or atrophy

  • Thyroid surgery

  • Radiation therapy to the thyroid or neck

• Pituitary and thyroid hormone regulation disorders

  • TSH-secreting pituitary adenoma

  • Thyroid hormone resistance syndrome

• Suboptimal levothyroxine replacement

• Medications

  • Lithium

  • Amiodarone

• Iodine-related disorders

  • Iodine deficiency

  • Excess iodine exposure