To report a case of a young female that presented with cystic space occupying lesion, that was initially thought of as a cystic tumor, and later turned out to be CNS hydatid infection.

A 25-year old female from Western India presented with complaints of headache and double vision. On examination, she had bilateral abducens nerve palsy, and imaging showed obstructive hydrocephalus with septate diverticulum in right lateral ventricle. Neurosurgical intervention in the form of third ventriculostomy with endoscopic septostomy was done, following which she was asymptomatic. However, in due course, she developed new symptoms in the form of right facial numbness, with examination showing sensory deficit in right trigeminal distribution, and repeat imaging showed intraventricular cystic lesion with grape like clusters. Differentials of Racemose NCC and rosette forming glioneural tumor were considered, and she was kept on close follow up. Interval imaging showed an extension of the cystic lesions with holocord involvement. In view of such a rapid spread, CNS hydatid was also thought of, and workup showed high total IgE levels with serology negative for cysticercosis and positive for Echinococcosis. Patient was started on steroids and antiparasitic agents, with which she had symptomatic improvement, with resolution of papilledema.

Parasitic infections as a cause of cystic brain lesions are found to be rare, and clinical suspicion, serial imaging, combined with early serological testing is important for accurate diagnosis and timely management.