New diagnostic signs in hydatid disease; radiography, ultrasound, CT and MRI correlated to pathology.

Seventeen of 70 patients with hydatid disease had verified Echinococcus granulosus infection of the chest. In 14 patients (20%), the primary location was the lung parenchyma. Two patients had primary and one secondary mediastinal hydatid cysts, and one patient a primary hydatid cyst of the chest wall. In three above-mentioned patients, secondary pleural involvement occurred, of which two were due to ruptured pulmonary cysts and one due to an hydatid cyst arising in the liver and having prolapsed into the chest. In all cases, clinical findings, radiography, ultrasound (US), computed tomography (CT) and/or magnetic resonance imaging (MRI) were correlated to macroscopic and microscopic pathology. Characteristic signs made recognition of hydatid disease possible, sometimes even when serologic tests had been non-conclusive. Assessment of other cysts throughout the body with or without involvement of neighbouring organs or tissues allowed appropriate therapeutic management. CT and MRI also played a key role in recognizing complications (e.g., rupture, infection of cysts).