Diagnosis and Management of Hashimoto's Thyroiditis

Clinical Presentation and Diagnosis

The American Academy of Family Physicians notes that Hashimoto's disease is the most common cause of hypothyroidism in developed nations where dietary iodine is adequate 1
The presence of an enlarged, non-tender thyroid gland on palpation is consistent with chronic lymphocytic thyroiditis, a characteristic of Hashimoto's thyroiditis 1
Markedly elevated thyroid peroxidase antibodies (120 IU/mL, normal <35) definitively establish autoimmune thyroiditis as the etiology 1
The American College of Radiology recommends that there is no role for thyroid ultrasound, CT, MRI, or radionuclide scanning in the workup of primary hypothyroidism in adults, as imaging does not differentiate among causes and all causes show decreased radioiodine uptake 2

The American Academy of Family Physicians suggests that patients with primary hypothyroidism due to Hashimoto's thyroiditis require levothyroxine replacement therapy, with a target TSH of 0.5-2.0 mIU/L 1