Rasmussen's Encephalitis

ABSTRACT

We herein report a case of intractable epilepsy that occurred in a 7-year-old girl, which is consistent with radiological and clinicopathological hallmarks of Rasmussen's encephalitis. The patient showed characteristic primary unilateral involvement with secondary bilateral propagation. Microscopically, the cortical atrophy due to neuronal loss, intense GFAP-immunoreactive astrogliosis, neuronophagia, perivascular lymphocytic infiltration and microglial nodules was seen throughout the cortex and white matter. No viral inclusions were noted; no cytomegalovirus, herpes simplex virus or Epstein-Barr virus was found by in situ hybridization. Granular immunofluorescence for C4, C1q and IgG within the blood vessel walls was noted, and ultrastructurally, only nonspecific vascular injury was found. Rasmussen's encephalitis is a diagnosis of exclusion; it can be diagnosed by the combination of clinical manifestation, neuroimaging and characteristic pathologic features.