Survey of herpes simplex virus infections of the central nervous system, including acute disseminated encephalomyelitis, in the Kyushu and Okinawa regions of Japan

We analysed data from 27 patients with herpes simplex virus (HSV) infections of the central nervous system (CNS) found in a 1990–1992 survey in Kyushu and Okinawa, Japan. Patients ranged in age from one year to 70 years, with peaks seen in the 20s and 50s. Temporal lobe-limbic encephalitis was the most common HSV infection (13 patients), followed by meningitis (5), diffuse encephalitis (4), disseminated encephalomyelitis (ADEM) (3) and brain stem encephalitis (2). Another three patients with non-herpetic, non-paraneoplastic acute limbic encephalitis were presented. Our study indicates that HSV infection can cause ADEM, although temporal lobe-limbic encephalitis or meningitis are more common. The early diagnosis of HSV-related ADEM is important because of the efficacy of the timely administration of corticosteroids.