Rasmussen encephalitis after traumatic brain injury in a young adult / Encefalite de Rasmussen após lesão cerebral traumática em um jovem adulto

Abstract

CASE PRESENTATION: Male, 33 years old, previously healthy, presented a single episode of epileptic seizure four years ago after a traumatic brain injury suffered in 2005. Throughout the evolution, seizures appeared as left eye blinks with progression to myoclonus in left hemiface, some with secondary generalization. It became more frequent, reaching about hundreds a day despite the use of carbamazepine CR 1200 mg/day, valproic acid 1500 mg/day and clobazam 60 mg/day. Video encephalogram demonstrated severe cortical dysfunction on the right hemisphere and focal epilepsy involving an ipsilateral perisylvian region. Magnetic resonance imaging revealed hippocampal sclerosis on the right, moderate volumetric reduction in the right hemisphere and cerebellum. The seizures became more frequent despite the drug adjustment with carbamazepine, acetazolamida and lamotrigina. In addition, left hand paresis appeared, and the condition evolved with epileptic status in May 2019 which partially improved after levetiracetam administration. After three months, a frontal and temporoparietal multilobar section was performed on the right hemisphere, and histopathological analysis demonstrated mild cortical atrophy, architectural disorganization of the neuronal layers and lymphohistiocytic infiltrate with microglial arrangement, compatible with Rasmussen encephalitis in subacute stage. DISCUSSION: Rasmussen encephalitis is a unilateral inflammatory brain disease of unknown etiology and progressive character. It typically manifests in childhood and early adolescence, although there are reports in adults after traumatic brain injury [1,2]. Clinically, it presents with polymorphics seizures that invariably increase in frequency, being refractory to antiepileptics. It necessarily evolves with hemiparesis, and, often, with cognitive impairment [3,4] Magnetic resonance imaging shows unihemispheric focal cortical atrophy, and electroencephalogram shows slow unihemispheric activity, with or without epileptiform activity and unilateral start of the crises. Histopathologically, there are dominant T cell encephalitis. Pharmacological management of the disease is inefficient and surgery is the preferably treatment. FINAL COMMENTS: Rasmussen encephalitis is a rare disease that typically begins in childhood and adolescence. It's pathophysiological relation with previous traumatic brain injury is not well defined. The clinical presentation is marked by cognitive deficit and polymorphic epileptic seizures, and surgery is the best option as treatment.