Herpes simplex encephalitis in infants and children.
BACKGROUND
The estimated incidence of herpes simplex encephalitis (HSE) is 2 to 4 per million of the population per year, of whom one-third are neonates or older children and two-thirds, adults. As effective antiviral therapy improves the high mortality and morbidity for younger patients with HSE, early diagnosis has become important, especially in children.


METHODS
Hospital records, neuroimages and electroencephalographic (EEG) findings of 10 Chinese infants and children with HSE were reviewed thoroughly over a 7-year period. Diagnosis of HSE was made via clinical setting of acute encephalitis with serological examinations of serum and cerebrospinal fluid (CSF).


RESULTS
Fever, consciousness disturbance and seizures were the most common clinical presentations on admission. Most of the CSF findings were mild pleocytosis (< 200/cumm), red cells, slightly elevated protein level and normal ratio of CSF/serum glucose concentration. All patients had abnormal features, by brain computerized tomography, and most had low densities over the temporal and frontal regions. Five patients underwent follow-up brain magnetic resonance imaging and most showed features of brain atrophy and demyelinating changes over the temporal and frontal regions. Generalized slow background activity was the most common EEG finding. Four patients' EEGs showed periodic laterizing epileptiform discharge. Intravenous administration of acyclovir (30 mg/kg/day) for 10 days was the drug-of-choice in these patients. All patients but the three deaths had psychomotor or mental retardation and spasticity. Six patients had epileptic sequelae, and one patient had the sequela of amnesia.


CONCLUSIONS
HSE remains a serious illness with high mortality and morbidity despite appropriate antiviral therapy. Adequate intravenous acyclovir therapy should be started as soon as possible. CSF examinations, EEG, serology, brain computerized tomography and magnetic resonance imaging may provide some clues of HSE, but negative findings should not deter or delay treatment in suspicious cases.
Shian
W J
WJ
Department of Pediatrics, Taichung Veterans General Hospital, Taiwan, R.O.C.
Chi
C S
CS
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D004660:Encephalitis / Q000175:diagnosis* / Q000628:therapy; D005260:Female; D006561:Herpes Simplex / Q000175:diagnosis* / Q000628:therapy; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012189:Retrospective Studies