Case Presentation: A 39-year-old previously healthy woman presented with left periorbital pain and rash, followed by progressive paresthesia in the left upper and lower extremities. She was initially diagnosed with preseptal cellulitis and discharged on cephalexin, but returned four days later with worsening paresthesia. She had recently traveled to Pennsylvania and Upstate New York, but reported no systemic or infectious symptoms. On admission, she was bradycardic to 50 and hypothermic to 96.9°F. An otoscopic exam showed vesicles in the posterior ear, no facial rash was present. Labs were notable for WBC of 6.82 cells/μL with 90% lymphocytes (20-45%).MRI brain/spine revealed a T2 hyperintense lesion in the left posterolateral medulla and cervicomedullary junction, suggestive of a demyelinating process. CSF studies showed WBC: 175 cells/μL (0-5 cells/μL), lymphocytes: 90% (40-80%), protein: 63 mg/dL (15-45 mg/dL), and glucose: 48 mg/dL (40-70 mg/dL). CSF studies were negative for infection. The patient received empiric acyclovir and high-dose steroids. Serum varicella-zoster virus (VZV) IgG resulted positive two days later. Neurologic status worsened over the next nine days with development of dysmetria, pronator drift and worsening left-sided weakness. AQP4-IgG returned positive, confirming neuromyelitis optica (NMO). The patient was treated with plasmapheresis and rituximab, with subsequent improvement in symptoms.
Discussion: VZV reactivation typically presents as herpes zoster, characterized by a painful vesicular rash in a dermatomal distribution. Complications include postherpetic neuralgia, herpes zoster ophthalmicus, meningitis, and cranial neuropathies such as Ramsay Hunt syndrome. In rare cases, VZV reactivation has been associated with CNS involvement and may serve as an immunologic trigger for autoimmune demyelinating conditions including NMO. NMO is an autoimmune demyelinating disorder of the central nervous system (CNS). It is characterized by autoantibody-mediated astrocyte injury targeting aquaporin-4 (AQP4), a water channel protein highly expressed in the optic nerves and spinal cord. While its exact pathogenesis is not fully understood, infections have been proposed as potential triggers. A systematic review of cases reported between 1975 to July 2020 identified 13 cases of NMO occurring after VZV reactivation, suggesting that VZV may act as an immunologic trigger in susceptible individuals (1). Our patient’s initial presentation with left periorbital pain and vesicular rash indicated zoster reactivation, but the presence of progressive sensory and motor deficits along with MRI findings pointed towards a central demyelinating process. The detection of AQP4-IgG confirmed the diagnosis of NMO. This case adds to the evidence suggesting that VZV reactivation may precipitate NMO in immunologically susceptible individuals.
Conclusions: Clinicians should have a high index of suspicion for NMO in patients presenting with neurological symptoms and a history of recent VZV reactivation, particularly when imaging suggests CNS demyelination. Early diagnosis and initiation of immunotherapy are critical to prevent irreversible neurologic impairment in patients with NMO.