Very rare.  Focal and progressive inflammatory encephalopathy of one cerebral hemisphere causing treatment-resistant partial epilepsy and a progressive deterioration of cognitive functions. Epilepsy crisis are focal or multifocal but unilateral; status epilepticus crises with continuous clonic activity of part of the body are common.

The pathophysiology is complex: it is probably an autoimmune phenomenon occurring after an infection; antigens normally protected by the blood-brain barrier are presented to lymphocytes T which triggers a cellular and humoral immune response. These antibodies are directed against the subunit 3 of the glutamate receptor. This response ultimately leads to the destruction of astrocytes and neurons.

Treatment: antiepileptics, corticosteroids at high dose IV, gamma globulin ... The only effective treatment is cerebral hemispherectomy.

Anesthetic implications:

epilepsy; corticosteroid therapy

References : 

• Mastrangelo M, Mariani R, Menichella A. 
  Rasmussen syndrome. 
  Eur J Pediatr 2010 ; 169 :919-24.

-         Flack S, Ojemann J, Habberkern C. 
Cerebral hemispherectomy in infants and young children. 
Pediatr Anesth 2008; 18:967-73.

Updated: November 2022