Abstract Details

Title Conus Medullaris Damage by West Nile Virus Infection

Topic Neuromuscular and Clinical Neurophysiology (EMG)

Presentation(s) P9 - Poster Session 9 (5:30 PM-6:30 PM)

Poster/Presentation
Number 11-005

Background Neurological complications by West Nile virus (WNV) may present with a wide spectrum of pathology ranging from meningoencephalitis to spinal motor neuron disease. Here, we report another unusual phenotype with pathology localized to the conus medullaris.

Objective NA

Design/Methods

Reviewed medical history, neurological examination, electromyogram (EMG) and cerebrospinal fluids (CSF) findings. Searched literature describing neurological manifestation of WNV.

Results A 46-year-old man presented with acute asymmetric flaccid paralysis of right leg which developed within 24 hours, as well as severe constipation. This event was preceded by 1 day of headache and fever. He had no sensory complaints. Pertinent physical findings include muscle weakness predominantly in the right leg (right-MRC 2/5, left- MRC 4/5) and reduced anal sphincter tone. His initial electrophysiological study and spinal magnetic resonance imaging (MRI) were normal. CSF examination revealed positive WNV IgM, protein 118 mg/dL, nucleated cells 178/CUMM (74%Lymphocytes). Repeated spinal MRI showed diffused cauda equina nerve enhancement. EMG 5 months later showed severe denervation within the myotome of lumbosacral roots.

Conclusions

Selective spinal motor neuron damages by WNV have been speculated due to retrograde virus transport of motor axons, which explains asymmetric flaccid paralysis in a subset of patients with WNV infection. However, clinical, imaging and electrophysiological findings in our case are suggestive of a selective damage in the spinal motor neurons of conus medullaris. This localization also explains the constipation and the involvement of anal sphincter in the patient. The combination of clinical phenotype has not been well described in literature. To our knowledge, there were only 10 reported cases of WNV associated conus medullaris involvement to date. Our report expands the clinical spectrum of WNV infection.

Authors/Disclosures
Ghadeer Fatani, MBBS (Monroe street Market) PRESENTER	Dr. Fatani has nothing to disclose.
Wan Yee Kong, MBBS (DMC)	Dr. Kong has nothing to disclose.
James F. Selwa, MD, MBA (Detroit Medical Center)	Dr. Selwa has nothing to disclose.
Maher Fakhouri, MD (University Health Center)	Dr. Fakhouri has nothing to disclose.
	No disclosure on file
Jun Li, MD, PhD, FAAN (Harris Methodist Hospital)	The institution of Dr. Li has received personal compensation in the range of $500-$4,999 for serving as a Consultant for FDA. The institution of Dr. Li has received research support from NIH. Dr. Li has a non-compensated relationship as a Associate Editor of ACTN journal with ANA that is relevant to AAN interests or activities.