Hashimoto's thyroiditis is also called autoimmune chronic lymphocytic thyroiditis. It is an autoimmune disorder , up to 95% of cases of Hashimoto's disease occur in women. patients present with elevated levels of circulating antibodies to thyroglobulin, thyroid peroxidase, and thyrotropin receptor. Most likely, autoimmune initiation is a result of both genetic predisposition and environmental factors. Additionally, a family history of autoimmune disorders has been shown to be a significant risk factor. A viral component has been postulated but remains unsubstantiated.
Hashimoto's is the most common cause of hypothyroidism. 20% of patients present with hypothyroidism and 5% present with hyperthyroidism, and 75% euthyroid. Patients have a relatively small, firm gland that is usually symmetrical but can be irregular. Usually patients present asymptomatically, and the goiter is found during routine physical examination. Occasionally patients may report awareness of a painless anterior neck mass.
Two important considerations include nontoxic multinodular goiter and thyroid lymphoma. The former is characterized by more distinct nodules in the gland, a euthyroid patient, and decreased circulating levels of the antibodies. Thyroid lymphoma can be a serious complication of Hashimoto's, and a fine needle aspiration (FNA) biopsy is recommended for any patient presenting with nodules or a rapidly increasing goiter.
For patients with overt hypothyroidism, it is necessary to prescribe thyroid hormone replacement therapy with the intent of establishing normal thyroid stimulating hormone (TSH) levels. Hormone replacement therapy for patients with subclinical hypothyroidism (normal free thyroxine [T4], free tri-iodothyronine [T3], and antibody levels but elevated TSH) is more controversial. In general, patients with TSH levels greater than 10 mU/L should receive therapy, and in all cases, long-term follow-up is necessary.
The Surgeon's Role
Papillary thyroid carcinomas may also occur in the setting of Hashimoto's thyroiditis. Surgery is indicated if malignancy is suspected from FNA biopsy. Additionally, thyroidectomy may be required in a patient with compressive symptoms from a large goiter or for cosmetic purposes. Surgical resection of a thyroiditis gland may be more technically challenging because of increased vascularity; the gland's firm, woody character; and dissection of the parathyroids off the gland itself.
Current Surgical Therapy , J. L. Cameron, 9 th eddition, 2008