“Agrypnia excitata” in a case of sporadic Creutzfeldt–Jakob disease VV2

Sporadic Creutzfeldt–Jakob disease (CJD) of the VV2 subtype (sCJDVV2) was diagnosed at autopsy in a 77-year-old man presenting with gait ataxia, daytime hypersomnolence and complex “oneiric” behaviours at wake–sleep transition. Video polysomnography was consistent with agrypnia excitata (AE). Diffusion weighted imaging (DWI) and 1H-MR spectroscopy (1H-MRS) revealed a severe thalamic and striatal involvement. Neuropathological examination showed widespread subcortical spongiosis, gliosis and neuronal loss with relative sparing of the cerebral neocortex. The present report includes the first demonstration of polysomnographic features consistent with fatal insomnia (FI) in sCJDVV2. Thus sleep–wake disturbance may reflect a similar underlying mechanism in prion disease, and be especially evident in those subtypes, such as FI and sCJDVV2, which show a predominant subcortical pathology associated with a relative sparing of the cerebral neocortex. AE is a generalised overactivity syndrome characterised by loss of slow wave sleep (SWS), mental oneirism and motor and autonomic sympathergic activation.1 AE has been described in FI, delirium tremens (DT) and Morvan’s chorea (MC).1 FI is a rare, usually hereditary, human prion disease, characterised by preferential loss of neurons and gliosis in the thalamus and inferior olives and a relative sparing of the neocortex. Polysomnographic features of FI are complete loss of sleep spindles and SWS and a severe reduction in total sleep time. EEG tracings in FI alternate between two states: wakefulness and “oneiric stupor”.2 While FI is well characterised, a limited number of polysomnographic data have been obtained to …