Herpes Simplex Virus Type 2 Radiculomyelitis Disguised as Conversion Disorder

Herpes simplex virus type 2 (HSV-2) is the most common cause of genital herpes with a seroprevalence of 20–30% in developed countries and 80% worldwide. In addition to neonatal encephalitis and meningitis, HSV-2 is associated with radiculomyelitis marked by pain, paresis, sphincter disturbances, sensory loss, or ascending necrotizing myelitis. We report the case of a patient with a lengthy psychiatric history who presented with lower extremity pain and weakness. Cervical, thoracic, and lumbar MRI scans with and without gadolinium contrast revealed no significant stenosis, neural compression, or other abnormal findings, and the brain MRI with and without gadolinium contrast was normal. The initial diagnosis was conversion disorder due to myriad psychological stressors. Polymerase chain reaction (PCR) of CSF detected HSV-2 and a lymphocytic pleocytosis, and the diagnosis of radiculomyelitis was confirmed. She was treated with i.v. acyclovir for 3 weeks followed by valacyclovir. The patient attained no improvement of her symptoms within 8 months; however, she reported decreased pain and improved strength of the lower extremities by 17 months. Neurologists should be aware of the association between HSV-2 and radiculomyelitis, particularly in the setting of a patient with psychiatric comorbidities. Recognition of HSV-2 through PCR of CSF and prompt treatment with acyclovir may prevent devastating neurological sequelae.