Fine-needle aspiration diagnosis of hydatid cyst.

The diagnosis of hydatid disease outside endemic areas is usually not suspected. Hydatid cysts in imaging studies can be confused with hepatic tumors, abscesses, cystadenomas, liver cysts or other lesions. Serology is the usual confirmatory test, but cytologic diagnosis has been described. Aspiration of the cysts has not been employed as a routine diagnostic method for fear of spillage and anaphylactic reactions. We report a case of unsuspected hepatic echinococcosis that was confirmed by fine-needle aspiration of the lesion and cytologic confirmation without complications.