Cortical dysplasia with prominent Rosenthal fiber formation in a case of intractable pediatric epilepsy.

[alexander disease]

We report a case of a 5 -year -old boy with intractable epilepsy who underwent therapeutic corticectomy . Histopathologic findings within the resection specimen included severe cortical dysplasia associated with abundant subpial and intraparenchymal Rosenthal fibers in a large right frontal lesion that merged into the basal ganglia . Rosenthal fiber proliferation may represent a reactive process , are frequent in pilocytic astrocytomas , and are a defining feature of Alexander disease . There was no evidence of neoplasm or leukodystrophy in this case . Genetic analysis of the specimen showed a few previously reported polymorphisms but no mutation in the GFAP gene . This case is unique among several hundred cortical resection specimens that we have studied , including numerous cases of severe cortical dysplasia .