Enlarged thyroid gland, usually due to thyroid hyperplasia, thyroid nodules, cysts or tumors resulting in enlarged thyroid gland, common causes are endemic goiter due to iodine deficiency, patients with viral infection of the thyroid gland or bacteria. Autoimmune diseases, like Hashimoto’s thyroiditis. Hyperthyroidism, hypothyroidism, some benign and malignant tumors of the thyroid gland can manifest as goiter, which can be diagnosed by checking thyroid function, ultrasound, or pathological examination.