Question

Hanna went to the doctor because she had a goiter on her neck that had grown quite large. What condition is Hanna MOST likely experiencing to cause this visible symptom?

Answer 1

Most likely an iodine-deficiency goiter: low iodine → decreased T3/T4 → loss of negative feedback → increased TSH stimulation of the thyroid → hypertrophy and enlargement of the gland. (Autoimmune thyroiditis such as Hashimoto’s or Graves’ disease can also produce goiters, but worldwide iodine deficiency is the most common cause.)