Wait and see: a 5 year history of 'recurrent dementia'.

Rapid evolving cognitive impairment can be the onset of either a progressive or a treatable dementia. We describe a case of a man in whom the clinical and laboratory presentation suggested a diagnosis of Creutzfeldt-Jakob disease, which subsequently turned into a diagnosis of voltage-gated potassium channel complex antibodies limbic encephalitis. The natural history and an increased knowledge of limbic encephalitis and the related antibodies led us to the correct diagnosis.