Neuronophagia of anterior horn neurons is characteristic of
A. JC virus infectionB. Treponema pallidum infection
C. Poliovirus infection
D. St. Louis encephalitis
Answer. C. poliovirus infection
>
Poliomyelitis is caused by an enterovirus that causes a nonspecific
gastroenteritis and then secondarily invades the anterior horn motor neurons of
the spinal cord. Microscopy reveals characteristic neuronophagia of anterior
horn neurons; the dorsal roots are not affected. Infection causes acute
muscular paralysis (atrophy, fasciculations, fibrillation, and hyporeflexia).
> Postpolio
syndrome occurs more than 25 years later, with progressive weakness, decreased
muscle mass, and pain. Progressive Multifocal Leukoencephalopathy (PML)
• In contrast,
progressive multifocal leukoencephalopathy (PML) is a viral infection of
oligodendrocytes that causes demyelination and symptoms of dementia and ataxia.
• The
pathognomonic feature of PML is oligodendrocytes in areas of demyelination
having a “ground-glass” appearance of their nuclei. PML occurs as a terminal
complication in immunosuppressed individuals.
