[A case of rubella encephalitis: rubella virus genome was detected in the cerebrospinal fluid by polymerase chain reaction].

We studied a 2-year-old boy who had been diagnosed as having rubella encephalitis by detection of rubella virus genome in his cerebrospinal fluid with the reverse transcription-polymerase chain reaction (PCR). PCR was considered to be very useful not only to make an early diagnosis of rubella encephalitis but also to be applied generally to that of various viral encephalitis.