A hydatid cyst of the thyroid gland.

Echinococcosis, although eradicated in many countries, is still widespread in communities in which agriculture is dominant, and cystic hydatidosis is a significant public health problem in regions where echinococcosis is endemic. Hydatid cysts may be found in almost any part of the body, but most often in the liver and lungs. Other organs affected occasionally include the brain, muscle, kidney, bone, heart and pancreas. This report documents a rare case with a cystic nodule in the thyroid detected by ultrasonography. The patient was a 40-year-old woman with an euthyroid multinodular goitre. Ultrasonography revealed a cystic nodule, and the ultrasonic appearance of the cyst liquid showed multiple echoes, suggesting that the nodule could be a hydatid cyst. Bilateral subtotal thyroidectomy was performed. Postoperative examination of the nodule showed it to be a solitary primary thyroid hydatid cyst.