Response to acyclovir in two cases of herpes zoster leukoencephalitis and review of the literature.

Herpes zoster leukoencephalitis is a rare complication of varicella-zoster virus infection. Associated with high mortality, the majority of cases have been discovered postmortem; today, however, magnetic resonance imaging is being used successfully as an aid in the diagnosis of this disease. The first two reported cases of HIV-infected patients with herpes zoster leukoencephalitis who recovered clinically and showed complete resolution of the magnetic resonance demyelination images after acyclovir treatment are described. In addition, the cases of herpes zoster leukoencephalitis reported in the literature to date are reviewed.