Subacute sclerosing panencephalitis in the differential diagnosis of encephalitis.

The authors describe five cases of subacute sclerosing panencephalitis (SSPE) identified through the California Encephalitis Project that emphasize the importance of considering SSPE in the differential diagnosis of encephalitis, particularly among pediatric patients. SSPE was not suspected in the differential diagnosis of three of the cases until results of measles testing were known. The diagnosis of SSPE is often not considered by clinicians because of its rarity in the United States and the nonspecific clinical manifestations at onset.