A 38-year-old woman has experienced the gradual onset of a goiter. Serum T4 and T3 are within the reference range and thyroid-stimulating hormone (TSH) is slightly increased. Serum antithyroid peroxidase (antimicrosomal) antibodies are detected
But there are no TSH receptor antibodies. Which of the following is the most likely diagnosis?

Question

Quizplus · Accepted Answer

The presence of antithyroid peroxidase antibodies and a slightly increased TSH level with normal T4 and T3 suggests chronic autoimmune thyroiditis, also known as Hashimoto's thyroiditis. Patients with chronic autoimmune thyroiditis or Hashimoto disease may demonstrate several different serum thyroid autoantibodies, but these vary from patient to patient. Thyroid peroxidase antibodies are found in roughly 85% of patients with Hashimoto disease, about 40% of patients with Graves disease, and in less than 15% of patients with other thyroid disorders. The absence of TSH receptor antibodies rules out Graves disease, making Hashimoto disease the most likely diagnosis.

A 38-Year-Old Woman Has Experienced the Gradual Onset of a Goiter