Echinococcus multilocularis Revisited

chinococcosis is a parasitic infection of humans caused by the larval stage of the tapeworm Echinococcus . Of the two main forms of the infection, the unilocular cystic form caused by E. granulosus is far more common than the rare multilocular alveolar form caused by E. multilocularis [1]. E. granulosus cysts are characterized by typical radiologic patterns that are easily diagnosed, but diagnosis of E . multilocularis lesions is more difficult. The alveolar cysts grow by exogenous proliferation and behave like a malignant neoplasm. Therefore, E. multilocularis lesions can cause physicians to generate a long list of differential diagnoses, including malignant tumors. However, making the correct diagnosis is possible if imaging findings are correlated with appropriate clinical findings. We give an overview of the various radiologic patterns produced by E. multilocularis lesions as seen on sonography, CT, and MR imaging and discuss the involvement of various organs and tissues and common complications.