Unusual manifestation of subacute sclerosing panencephalitis: case with intracranial high-pressure symptoms.

Subacute sclerosing panencephalitis can show variations in clinical course, and some ophthalmologic abnormalities can be seen as cortical blindness and optic atrophy. A 4-year-old girl was referred to our hospital with a complaint of diplopia, vomiting, and ataxia. On physical examination, she was found to have stage IV papilledema with retinal hemorrhage. She was diagnosed as having idiopathic intracranial high pressure until magnetic resonance imaging demonstrated T2-weighted hyperintense lesions. After observation of head drop attacks and detection of elevated antimeasles antibodies in cerebrospinal fluid, the diagnosis of subacute sclerosing panencephalitis was established, and isoprinosine and carbamazepine were started for treatment. However, because carbamazepine failed to control the head drop attacks, topiramate was also included, and the attacks were kept under control with topiramate. The case presented in this article is a good example of subacute sclerosing panencephalitis in which, at early stages, some of the signs and symptoms can lead to an erroneous diagnosis. In addition, we have demonstrated that topiramate might be a good choice for treatment for the persistent myoclonus seen in this type of patient.