ACYCLOVIR VERSUS VIDARABINE IN HERPES SIMPLEX ENCEPHALITIS: Randomised Multicentre Study in Consecutive Swedish Patients

127 patients with suspected herpes simplex encephalitis (HSE) were entered in a prospective randomised study of acyclovir 10 mg/kg 8-hourly versus vidarabine 15 mg/kg daily for 10 days. The patients were consecutive and nearly all Swedish cases of HSE were included; they were treated in six university infectious diseases departments. The diagnosis of HSE was verified by brain biopsy and/or antibody responses in serum and cerebrospinal fluid. Of 53 confirmed cases of HSE (corresponding to 2·3 cases per million inhabitants per year in Sweden), 51 (27 acyclovir, 24 vidarabine) were evaluable for analysis of efficacy. The mortality was 19% in the acyclovir-treated group versus 50% in the vidarabine group (p=0·04). At 6 months of observation 15 (56%) of 27 acyclovir-treated patients had returned to normal life compared with 3 (13%) of 24 vidarabine-treated patients (p = 0·002); and the numbers who died or had severe sequelae were 9 (33%) and 19 (76%), respectively (p=0·005). No important or new adverse events were recognised.