Hashimoto's Thyroiditis is swelling (inflammation) of the thyroid gland that often results in reduced thyroid function (hypothyroidism). This condition is the most common cause of hypothyroidism in the United States in individuals older than 6 years. It is part of the spectrum of autoimmune disease. Chronic thyroiditis or Hashimoto's disease is a common thyroid gland disorder. It is caused by a reaction of the immune system against the thyroid gland. It can occur at any age but is most often seen in middle-aged women Chronic thyroiditis is most common in women and people with a family history of thyroid disease. Hashimoto's disease may in rare cases be associated with other endocrine disorders caused by the immune system. Hypothyroidism typically has an insidious onset with subtle signs and symptoms that may progress to more advanced or even florid signs and symptoms over months to years. Symptoms Enlarged neck or presence of goiter Constipation Mild weight gain Dry skin Fatigue Diagnosis of Hashimoto's disease is by: Free T4 test (low) Serum TSH (high) Thyroid auto antibodies Fine Needle Biopsy: Hashimoto thyroiditis is a histologic diagnosis. Treatment of Hashimoto's disease is by: Thyroid hormone replacement Removal of malignant nodule Prevent obstruction to the trachea or the esophagus causing breathing and swallowing difficulty TABLE OF CONTENT Introduction Chapter 1 Hashimoto Thyroiditis Chapter 2 More Facts about Hashimoto Thyroiditis Chapter 3 Treatment of Hashimoto Thyroiditis Chapter 4 Hypothyroidism Chapter 5 Goiter Chapter 6 Congenital Hypothyroidism Epilogue