B cells and epilepsy

Rasmussen’s encephalitis (RE) is a rare disease that typically begins between the ages of 2 and 10 with focal seizures. Described initially by Rasmussen et al.1 in Neurology in 1958, the process usually begins with focal seizures that are poorly responsive to antiseizure medications. Remarkably, the cerebral hemisphere from which the seizures arise undergoes progressive destruction over periods ranging from months to decades, resulting in the loss of motor, sensory, visual, and cognitive functions subserved by the destroyed hemisphere. Neuroimaging reveals the progressive atrophy of the hemisphere. The disease mainly affects cortical gray matter with perivascular monocytic infiltrates, microglial nodules, astrogliosis, and neuronal loss. A functional hemispherectomy is the definitive treatment, eliminating the seizures but leaving residual irreversible neurologic deficits. In this issue of Neurology , Baranzini et al.2 add to emerging evidence implicating an immune component to the pathogenesis of this intriguing disease. A clue to the presence of an autoimmune mechanism arose from the fortuitous occurrence of epileptic seizures in rabbits that had been immunized with a subunit of the AMPA …