[Necrotic plaque formation in a case of frontal lobe multiple sclerosis].

We reported an unusual case of multiple sclerosis (MS), clinical manifestations and neuroimagings of which were restricted to the frontal lobes and Gd-enhancing plaques on MRI later changed to necrotic lesions. A 36-year-old previously healthy man developed behavioral changes without any other neurological manifestations in a few weeks. Findings of magnetic resonance imaging (MRI) together with visual evoked potentials pointed to MS and corticosteroid pulse-dose therapy was initiated. Despite fairly uneventful, but rather delayed clinical recovery, repeated MRI disclosed rows of multiple, periventricular plaques localized to the bilateral frontal white matter and indicated the majority of lesions were not those of demyelination but necrosis. Frontal lobe syndrome is rarely encountered as a sole manifestation and rates only a few percent of MS cases in the literature. We speculated on the pathogenesis of necrotic plaques in this particular case; tumor necrosis factor, interleukin-1 and other cytokines that are known to be accompaniments of inflammatory cell infiltrates and activated glia in MS may ultimately destroy the CNS tissue, if the inflammation is not readily controlled. It is not certain, however, that what are determinants of demyelination and what drives further to the devastating tissue necrosis. Despite the uncertainty, this case indicates a necessity of immediate institution of adequate immunosuppressive therapy when neuroimaging study indicates active inflammation and openings of the blood-brain barrier in demyelinating plaques.