Intrathoracic Extrapulmonary Hydatid Disease: Radiologic Manifestations

Hydatidosis is a parasitic disease caused by the larvae of Echinococcus granulosus and rarely by Echinococcus alveolaris. It is endemic to South America, North Africa, Asia, Australia, and the Middle East [1,2]. The definitive hosts are foxes and, less commonly, dogs and cats. Humans are infected by direct contact with an infected animal or by ingestion of contaminated food or fluids. Echinococcal embryos migrate through the intestinal mucosa, and, in 60%e70% of cases, reach the liver via the portal system [1]. They can then enter the systemic circulation via the porta caval anastomoses and be carried by the bloodstream to any organ or tissue in the body. Alternatively, the eggs can be inhaled and cause primary lung disease [2]. Intrathoracic extrapulmonary hydatid disease is very rare but can occur in the pleural space, extrapleural region, pleural fissure, chest wall, mediastinum, pericardium, myocardium, and diaphragm [1]. In this pictorial essay, we present the clinical manifestations and imaging features of patients with hydatid cysts (HC) in the extrapulmonary sites of the thorax.