Successful early treatment with acyclovir and corticosteroids for acute myelitis associated with zoster sine herpete: a case report

A 79-year-old man presented with chest and back pain on the right side but with no cutaneous lesions. He had received oral corticosteroids and immunosuppressants for systemic lupus erythematosus. He had spastic paraplegia, sensory disturbance in the lower limbs, and dysfunction of the bladder and bowel. He showed mononuclear-dominant pleocytosis and elevated proteins in the cerebrospinal fluid (CSF), and a decreased CSF/blood glucose ratio. Although polymerase chain reaction techniques found no varicella-zoster virus (VZV) DNA, VZV IgG antibodies were elevated in both the serum and CSF, and the VZV IgG index was dramatically elevated. MRI revealed no lesions in the brain or spine. However, somatosensory evoked potentials in the tibial nerve showed abnormal prolongation of the central sensory conduction time. We diagnosed the patient with acute myelitis associated with zoster sine herpete (ZSH). He received acyclovir and intravenous methylprednisolone pulse therapy in the early stage, and his symptoms and CSF findings completely recovered. We conclude that acute myelitis associated with ZSH should be treated as soon as possible because VZV infection may induce necrotizing myelitis if the treatment is delayed.