Cerebral sparganosis: the wandering lesion.

A 38-year-old Japanese man presented with a 2-year history of cerebellar ataxia, fever, and headaches. MRI revealed migration of the lesion (figure, A–C). CSF cytology showed eosinophilic meningitis (figure, D); serum and CSF ELISA were positive for Spirometra erinaceieuropaei. Human sparganosis is a rare parasitic infection by the larval cestode of Spirometra that results from ingesting the plerocercoid harbored in frogs, snakes, and chickens. Reported worldwide, sparganosis is most prevalent in Southeast and Eastern Asia. The diagnosis is suggested by a wandering lesion, especially in endemic areas; the tunnel sign on postcontrast MRI is characteristic.1 The preferred treatment is the surgical removal of live worm.