Pediatric Epstein-Barr virus-associated encephalitis: 10-year review.

Many neurologic manifestations of Epstein-Barr virus (EBV) infection have been documented, including encephalitis, aseptic meningitis, transverse myelitis, and Guillain-Barré syndrome. These manifestations can occur alone or coincidentally with the clinical picture of infectious mononucleosis. Since 1994, The Hospital for Sick Children has maintained a prospective registry of all children admitted with acute encephalitis. This report summarizes all cases of Epstein-Barr virus-associated encephalitis compiled from 1994 to 2003. Twenty-one (6%) of 216 children, median age 13 years (range 3-17 years), in the Encephalitis Registry were identified as having evidence of Epstein-Barr virus infection. This evidence consisted of convincing Epstein-Barr virus serology and/or positive cerebrospinal fluid polymerase chain reaction (PCR). One patient had symptoms of classic infectious mononucleosis; all others had a nonspecific prodrome, including fever (n = 17; 81%) and headache (n = 14; 66%). Slightly less than half (n = 10; 48%) had seizures and often had electroencephalograms showing a slow background (n = 12; 57%). Many demonstrated cerebrospinal fluid pleocytosis (n = 17; 81%), and 71% (n = 15) had abnormal magnetic resonance imaging findings. Two patients died, 2 suffered mild deficits, and 16 were neurologically normal at follow-up. Most patients with Epstein-Barr virus encephalitis do not show typical symptoms of infectious mononucleosis. Establishing a diagnosis of Epstein-Barr virus encephalitis can be difficult, and, consequently, a combination of serologic and molecular techniques should be used when investigating a child with acute encephalitis. Most children make full recoveries, but residual neurologic sequelae and even death can and do occur.