In summary, our findings suggest that involvement of WNV with anterior horn cells
, which resulted in a poliomyelitislike syndrome, represents the most common underlying cause of paralysis with WNV infection.
Electrodiagnostic studies showed widespread but variable denervation, reduced compound muscle action potentials (CMAPs), and normal sensory nerve action potentials (SNAPs), consistent with a severe, asymmetric process affecting anterior horn cells
or motor axons.
AFP can include clinical syndromes caused by acute dysfunction of the anterior horn cells
(e.g., acute flaccid myelitis), peripheral motor nerves or nerve roots (e.g., Guillain-Barre syndrome), neuromuscular junction (e.g., botulism or myasthenic crisis), or muscle (e.g., acute myopathies) (3,4).
The WNV outbreaks that occurred in New York City in 1999, and Israel in 1998, resulted in 10% of people experiencing bilateral flaccid paralysis (Klein, et al., 2002; Nash, 2001) With bilateral flaccid paralysis, WNV attacks the anterior horn cells
causing acute flaccid paralysis, resulting in a poliomyelitis-like syndrome (Li et al., 2003; Sejvar et al., 2003).
Inflammatory cells were clustered around dying anterior horn cells
, which is an indication of neuronophagia.
Destruction of the spinal anterior horn cells
may cause acute flaccid paralysis (AFP), presenting as asymmetric limb weakness, hypoflexia or areflexia, and acute bowel or bladder dysfunction that may appear without signs of meningoencephalitis.
In the cases of WNV-associated AFP, clinical, laboratory, and electrophysiologic findings suggested pathology localized to anterior horn cells
and motor axons, similar to that seen in acute poliomyelitis.
The poliovirus infects the spinal cord anterior horn cells
and other motor neuron cells.
* postural integrity: muscle tone that helps maintain posture * reflex arcs: reflexes within the spinal cord * percutaneous thermal rhizotomies/rhizotomies: surgical destruction of spinal-nerve roots to eliminate pain * intrathecal pump: baclofen spinal-cord pump * intrathecal pump: baclofen spinal-cord pump * anterior horn cells
: the nerve supply to muscles * neuroma formation: scar tissue on the nerves
Spinal Muscular Atrophy (SMA) is a degenerative disease of the anterior horn cells
that presents with progressive generalized weakness, absent reflexes, feeding problems along with hypotonia.