Imaging of Hydatid Disease with a Focus on Extrahepatic Involvement

Abstract

The authors review the causes and origins of hydatid disease, with a focus on imaging features of the extrahepatic manifestations of echinococcosis; familiarity with the associated clinical findings at presentation, imaging features, and treatment can aid in diagnosis and treatment. Hydatid disease (HD) is a parasitic infection caused by the larvae of a tapeworm that is endemic to many regions around the world—South America, Africa, and Asia, in particular. Humans are infected as intermediate hosts in the parasite’s life cycle; thus, HD can be seen in persons living in areas where animal husbandry is practiced. However, owing to the varied patterns of migration and immigration during the past several decades, HD can be diagnosed in individuals living anywhere. The liver is the most common organ involved, with hepatic HD accounting for the majority of published cases. However, HD can affect multiple organs and tissues other than the liver, including the spleen, kidneys, lungs, heart, peritoneum, muscles, and brain. Knowledge of the route of spread, clinical findings at presentation, and possible complications involving each extrahepatic location can be useful for the radiologist when evaluating imaging findings in patients suspected of having HD. The ultrasonographic, computed tomogra...