Rasmussen encephalitis is a rare chronic neurological disorder, characterised by unilateral inflammation of the cerebral cortex, drug-resistant epilepsy, and progressive neurological and cognitive deterioration. It predominantly affects children, with the onset in adults having a milder course. Infection occurring around two weeks prior to onset is observed in 38% of the patients. There is evidence of autoimmune involvement in the pathogenesis. The immunopathology of this disease is attributed mainly to activated cytotoxic T cells. It has been reported that genetic variations of immunoregulatory genes associated with Rasmussen syndrome.