[A case of solitary neurocysticercosis of unknown transmission route]

We report a case of solitary neurocysticercosis of unknown transmission route. A 26-year-old male was taken to our hospital with a history of general convulsions. On admission, physical and neurological findings were normal. On the basis of neuroimaging (computed tomography scan and magnetic resonance imaging), initial diagnosis was brain abscess and the patient was treated with antibiotics. Two months later, the patient, at times, presented a loss of consciousness. The follow-up MRI revealed that the enhanced lesion became enlarged and perifocal edema became evident, so the patient was surgically treated. By histopathological examination, the lesion was diagnosed as a cysticercus. The immunoserologic assay gave a positive result for the disease. Postoperatively, the symptoms improved. Cerebral cysticercosis is the most common parasitic disease of the central nervous system, but rare in Japan. Therefore its diagnosis remains difficult, especially in the case of solitary cerebral cysticercosis, which has been reported only 7 times in Japan. The pathological examination or the immunoserologic assay should be taken into consideration to obtain definitive diagnosis of cerebral cysticercosis.