Atypical clinical course subacute sclerosing panencephalitis presenting as acute Encephalitis.

We report a 14-year-old boy who presented with loss of consciousness and gait instability. The electroencephalogram (EEG) showed generalized slowing with irregular activity and cerebral magnetic imaging revealed asymmetrical nonspecific signals on basal ganglia. His second electroencephalogram revealed periodical generalized high-voltage slow wave complexes which did not disappear with diazepam induction. Subacute sclerosing panencephalitis (SSPE) was considered and the diagnosis was confirmed with the identification of measles antibodies in cerebrospinal fluid. Our findings show that SSPE should be in mind in the differential diagnosis of meningoencephalitis and acute disseminated encephalomyelitis and highlight the significance of EEG in the diagnosis of unidentified cases.