Diagnostic criteria for sporadic Creutzfeldt‐Jakob disease still missing psychiatric features

Dr Foster and colleagues report a pat ient in whom depress ion caused ‘diagnostic overshadowing’ of sporadic Creutzfeldt-Jakob disease (SCJD).1 Reporting a similar case some years ago,2 my colleagues and I pointed out the inadequacy of the then existing (2009) diagnostic criteria for sCJD, which eschewed any mention of psychiatric symptoms despite an evidence base that described them as being not infrequently present. The sCJD criteria have subsequently (2017) undergone revision,3 but as before the focus is on rapid cognitive decline and certain neurological signs as well as EEG, MRI, and CSF findings, with no mention of psychiatric features. In contrast, variant CJD is acknowledged as a ‘neuropsychiatric disorder’, and even some genetic forms (ie with a pathogenic mutation in the PRNP gene) are noted to be associated with neuropsychiatric disorder.3 Although the revised criteria appear to work relatively well for sCJD, particularly increasing sensitivity versus the prior criteria,4 the absence of any mention of psychiatric features suggests that cases such as that reported by Foster et al. will continue to occur.