Cerebral alveolar echinococcosis. A case report with MRI and review of the literature.

Alveolar echinococcosis is an important zoonotic infection caused by the larval stage of the Echinococcus multilocularis. It is endemic to North America, Central Europa, Russia, China and Turkey. The liver and the lung are the organs most commonly involved. Cerebral alveolar echinococcosis is rare accounting for only 1% of cases. We present a 55-year-old patient with a right frontal mass. T2-weighted MRI series revealed a grape like multilobular, heterogeneous mass with low density. A diagnosis of glial tumor was made. The mass was totally removed. The histopathological examination showed a diffuse growth composed of compartments that are filled with a gelatinous matrix and many brood capsules and protoscolices filled with necrotic tissue. Histopathological findings were consistent with the diagnosis of alveolar echinococcosis. No postoperative complications were observed. There were no lesions in the liver and lungs. The patient was started on albendazole (ABZ) at a daily dosage of 800 mg for 3 months. The patient has remained free of any mass lesion for 5 years. Hypointense grape-like mass with calcification and surrounding white matter edema in T2-weighted MRI should suggest cerebral alveolar echinococcosis. Radical surgery and an adjuvant therapy with ABZ provides useful prolongation of life.