Transverse Myelitis in the Setting of Enterobius vermicularis (Pinworm) Infection: Case Report.

Myelitis is a rare inflammatory myelopathy, and known associated etiologies only account for a small number of causes. A significant percentage of cases have an unknown etiology and are considered idiopathic. With 64% to 68% of cases fitting into the idiopathic category, helminth infections, and specifically pinworm parainfections, should be considered in cases that would otherwise be classified as idiopathic. This case report outlines a pediatric patient diagnosed with myelitis given her progressive weakness, fussiness, refusal to bear weight as well as magnetic resonance imaging (MRI) demonstrating T2-hyperintense signal and/or T1 gadolinium enhancement, and/or positive cerebrospinal fluid (CSF) inflammatory markers. This patient had a negative evaluation for typical known etiologies for myelitis including no signs of multiple sclerosis and neuromyelitis optica spectrum disorder on brain MRI, oligoclonal banding and aquaporin-4 autoantibodies, and no evidence of bacterial or viral meningitis given normal cell counts and cultures in CSF. She was found to have a pinworm infection, suggesting a parasitic parainfectious etiology of her myelitis. This case outlines the first case noting the correlation between myelitis and pinworm infection in a pediatric patient.