Hashimoto’s disease is an autoimmune condition that is common cause of hypothyroidism. In Hashimoto’s thyroiditis, the body mounts an immune reaction against its own thyroid gland tissue, leading to inflammation of the gland (thyroiditis). Hashimoto’s thyroiditis is a condition caused by inflammation of the thyroid gland. It is an autoimmune disease, which means that the body inappropriately attacks the thyroid gland – as if it was foreign tissue. As hypothyroidism becomes more severe, there may be puffiness around the eyes, a slowing of the heart rate, a drop in body temperature, and heart failure. Other symptoms and signs include, swelling of the thyroid gland (due to the inflammation), which can cause a feeling of tightness or fullness in the throat, a lump in the front of the neck from the enlarged thyroid gland called a goiter, and/or difficulty swallowing solids and/or liquids due to the enlargement of the thyroid gland with compression of the esophagus.