Echographic Evaluation of Hepatic Echinococcus

Abstract

Background: Hydatid disease is a parasitic infestation by a tapeworm of the genus Echinococcus. It is not endemic in the United States, but the change of immigration patterns and the improvement of transcontinental transportation over the past 4 decades have caused a rise in the profile of this previously unusual disease throughout North America. This has led to the necessity for physicians to be more aware of its clinical features, diagnosis, and management. Pathophysiology: Human echinococcosis is a zoonotic infection caused by the tapeworm of the genus Echinococcus. Of the 4 known species of Echinococcus, 3 are of medical importance in humans. These are Echinococcusgranulosus, causing cystic echinococcosis (CE); Echinococcusmultilocularis, causing alveolar echinococcosis (AE); and Echinococcusvogeli. E granulosus is the most common of the three. E multilocularis is rare but is the most virulent, and E vogeli is the most rare. Frequency: In the US: Despite the rise in occurrence, echinococcosis remains a very rare disease (<1 case per 1 million inhabitants) in the continental United States. Northern Alaska has endemic areas of E granulosus, but the frequency of infection remains low (<1 case per 100,000 inhabitants).

Keywords: Echinococcus, geographic distribution of the echinococcal worms, Echinococcus granulosus cysts, ultrasound examination, etc.