A Case of Treatment-Resistant Hyperthyroidism: The Need for a Broad Differential Diagnosis

Hyperthyroidism is a disease caused by increased production of thyroid hormones that can affect all organ systems within the body. The systemic effects of hyperthyroidism are diverse, ranging from palpitations and anxiety to thyroid storm and cardiogenic shock. Hyperthyroidism commonly is caused by autoimmune stimulation of the thyroid gland, nodules, and thyroiditis. We present a rare case of struma ovarii causing hyperthyroidism and atrial fibrillation.