Altered EEG in Creutzfeldt-Jakob Disease: Improving Diagnostic Accuracy Using American Clinical Neurophysiology Society 2021 Criteria.

BACKGROUND AND

OBJECTIVES

Creutzfeldt-Jakob disease (CJD) is a rapidly progressive neurodegenerative disease characterized by significant changes in EEG and structural alterations on MRI. Both are integrated in the current World Health Organization (WHO) surveillance criteria of CJD. We aimed to re-evaluate the EEG recordings, along with clinical and MRI data, in patients with different subtypes of definite CJD by applying the adapted American Clinical Neurophysiology Society (ACNS) criteria, 2021.

METHODS

Fifty-one routine EEG recordings in 16 patients with sporadic CJD were reanalyzed.

RESULTS

Generalized slowing, according to standard terminology, was present in 94% of patients. Generalized periodic discharges (GPDs) and generalized rhythmic delta activity (GRDA), as defined by the 2021 ACNS criteria, occurred frequently (31% and 38%, respectively). The differentiation from ictal activity may be challenging because 25% (4/16) of the patients fulfilled the criteria of the recently proposed ictal-interictal continuum (IIC) in at least 1 EEG. By contrast, no status epilepticus (SE) was observed. The EEG alterations varied among the different CJD molecular subgroups: more cortical involvement in MM/MV1 and mixed MM/MV1 + 2C histotypes was associated with periodic discharges (PDs) (57% and 80%) and also IIC (43% and 20%). We could not detect any PD or IIC in patients with the VV1 or MV2K (predominant subcortical pathology) histotype.

DISCUSSION: Assessing the EEGs according to the 2021 ACNS criteria may help prevent misdiagnosis of nonconvulsive status epilepticus, and repetitive recordings may help in earlier diagnosis of CJD.