Longitudinally extensive transverse myelitis with encephalopathy following acute dengue infection

Abstract

Dengue is a common arboviral infection in tropical/subtropical regions; neurologic complications occur in ~5% of cases, usually as encephalopathy from systemic illness (1). Viral neurotropism and immune-mediated injury are rare and mimic infectious/inflammatory etiologies (2,3). Although corticosteroids are not routinely recommended, case reports describe high-dose steroids usage with favorable outcomes (4,5).

A previously healthy 25-year-old man in Brazil developed fever and retro-orbital headache followed by disorientation, hallucinations, abdominal pain, urinary retention, and rapidly progressive areflexic paraparesis. CSF showed lymphocytic pleocytosis (140 cells/µL); infectious and autoimmune/demyelinating tests were negative. MRI revealed longitudinally extensive intramedullary hyperintensity from upper cervical cord to conus with leptomeningeal enhancement. Dengue IgM with IgM/IgG seroconversion confirmed acute infection. IV methylprednisolone (1 g/day) improved symptoms within 72h; he walked by day 5 and fully recovered within 1 year.

In endemic settings, neurodengue is a possibility when alternatives are excluded. Once infection is ruled out, immunotherapy should be considered.