A woman in her 30s was working as a nurse’s aide in an intensive care unit, regularly practiced sports, and had severe asthma treated with corticosteroid therapy. She was hospitalized for a urinary retention associated with pluriradicular sacral neuropathic pain and discrete bilateral weakness of the lower limbs. Spinal cord magnetic resonance imaging revealed a T2 hyperintensity, and contrast enhancement from T12 to the conus medullaris and cauda equina roots. Brain magnetic resonance imaging showed no abnormality. Findings of infectious, inflammatory, and metabolic biological investigations were normal except for a multiplex polymerase chain reaction in the cerebrospinal fluid detecting the herpes simplex virus type 2 genome. A diagnosis of herpetic myeloradiculitis was made (Elsberg syndrome), and a treatment with aciclovir, 800 mg per 8 hours, was administered intravenously for 14 days. Despite this treatment, urinary retention and neuropathic pain persisted. One month later, her symptoms rapidly worsened without any identified factor, and she became almost completely paraplegic. Findings of cerebral and spinal cord magnetic resonance imaging, cerebrospinal fluid analysis, and electroneuromyographic study as well as sensory and motor evoked potentials were normal. Despite rehabilitation, a nearly complete flaccid paraplegia persisted, including muscular contractions without any observed movement and the need for a wheelchair. However, some discrepancies on motor examination (including fluctuating motor deficit on different maneuvers) suggested a functional neurological disorder (FND).1 Given the extent of the symptoms, positive clinical signs of FND were difficult to demonstrate. Additionally, several physicians involved in her care questioned the diagnosis of FND because of the initial myeloradiculitis, the clinical severity, and the need for self-catheterization 8 times a day.