Background: Although autoimmune encephalitis is a rare disease with an incidence of 0.8/ 100,000, it is associated with cognitive decline, epilepsy, behavioural disturbances, and impairment in the level of consciousness. Therefore, prompt diagnosis and treatment lead to improvement or full recovery in most cases [6]. Encephalitic syndromes are a common medical emergency. The importance of early diagnosis and appropriate treatment is paramount. If initial investigations for various conditions including infectious agents prove negative, other diagnoses must be considered promptly. Autoimmune encephalitis are being increasingly recognized as important (and potentially reversible) non-infectious causes of an encephalitic syndrome [1]. Some encephalitis or seizure disorders once thought idiopathic now seem to be immune mediated [3]. In 2010 the spectrum of known antigens in autoimmune encephalitis has been expanded by GABAB receptors. Until now over 80 patients with GABAB receptor encephalitis have been described [2].