Causes of fever in children with first febrile seizures: how common are human herpesvirus-6 and dengue virus infections?

This study was conducted to evaluate the etiologies of pyrexia in children with first febrile seizures using a prospectively recorded medical protocol, bacterial culture, and serologic tests for human herpesvirus-6 (HHV-6), dengue virus and Japanese B encephalitis (JE) virus. Of 82 children with first febrile seizures, who were between 3 months and 3 years old and had been admitted to Bhumibol Adulyadej Hospital between January 1997 and December 1998, 41 were boys and 41 were girls, with a mean age of 14.7 months. The average maximal body temperature was 39.7 degrees C. Approximately 70% of the children developed seizures on the first day of fever and the duration of the seizures varied from 1 to 30 minutes. In addition to fever and seizure, common symptoms and signs included coryza, diarrhea, vomiting, inflamed tympanic membranes and rash. The causes of fever documented upon discharge were, in order of frequency, upper respiratory tract infection, nonspecific febrile illness, diarrhea, urinary tract infection, viral infection, pneumonia, herpangina, measles, pneumococcal bacteremia and dengue fever. Serologic tests for HHV-6 IgM were positive in seven children (8.5%), and serologic tests for dengue and JE viruses were negative in all cases.