Varicella-zoster virus myelitis: an expanding spectrum

We report four cases of varicella-zoster virus (VZV)-associated myelopathy in adults. Myelopathy was remitting-exacerbating in two remarkable instances, once acute and once chronic. VZV myelopathy was diagnosed based on the close temporal relationship between rash and onset of myelopathy, and for the first time, by polymerase chain reaction, which revealed VZV DNA in the cerebral spinal fluid of three patients with pleocytosis weeks to months later. Magnetic resonance imaging was abnormal in three of four patients. Although all four patients were treated at some time with intravenous acyclovir, concomitant treatment with steroids and the presence of acquired immunodeficiency syndrome in one patient prevented conclusions about a favorable response to therapy. Myelopathy after VZV infection may be remitting-exacerbating in addition to acute or chronic. Detection of VZV DNA in cerebral spinal fluid months after rash was useful for diagnosis and suggests a role for virus in the pathogenesis of myelopathy.