The diagnostic dilemma of non-convulsive status epilepticus in sporadic Creutzfeldt-Jakob disease

Summary Introduction The differentiation between the clinical and electroencephalographic changes in noncon-vulsive status epilepticus (NCSE) and those in sporadic Creutzfeldt-Jakob disease (sCJD) is a crucial question. Case report A 77-year old woman was admitted because of fluctuating behavioural chancaseges, adynamia and apraxia since several months for diagnostic. The diagnosis of sCJD was suggested. Subsequently, she had a generalized tonic clonic seizure (GTCS) and the EEG revealed periodic lateralized epileptiform discharges and NCSE was considered. Discussion The presented case illustrates the dilemma in the differential diagnosis of sCJD and (symptomatic) NCSE in the light of the recently published new Salzburg consensus criteria and unified EEG terminology. Concerning these criteria, the patient showed after an initial generalized seizure and substantial clinical improvement after administration of antiepileptic drugs, persisting epileptic discharges and only subtle clinical ictal phenomena during the EEG patterns with typical spatiotemporal evolution as a correlate of a symptomatic NCSE. During the further course of the disease in the presented patient the picture changed into an encephalopathic pattern. Conclusion EEG criteria for the diagnosis of NCSE are complex. In our case the EEG resembled the pattern of NCSE in the postictal phase of a GTCS according to a classification of NCSE in use at this time. After initial responsiveness to antiepileptic medication the patient lost responsiveness to therapy displaying the typical encephalopathic EEG findings in sCJD. These findings may support the hypothesis of initial NCSE and transformation into prion protein induced encephalopathic EEG and demonstrated clinical usefulness of the Salzburg consensus criteria for NCSE.