Illustrating the relevance of updated diagnostic criteria for sporadic Creutzfeldt-Jakob disease: a teaching neurocase.

A 75-year-old woman with unremarkable medical history, consulted for a 5-month history of involuntary shaking of left upper limb. Clinical examination revealed polyminimyoclonus of the upper limbs with cogwheel-like rigidity, hyperreflexia, bradykinesia, inconstant spastic-like rigidity in the lower limbs and a stiff and cautious gait. These symptoms, together with the memory impairment found on neuropsychological assessment yielded suspicion for a subacute encephalopathy probably due to a non-conventional infectious agent. There was no 14-3-3 protein found in the cerebrospinal fluid and no periodic sharp wave complexes on EEG. These findings made the diagnosis of Creutzfeldt-Jakob disease (CJD) rather unlikely according to the current WHO diagnostic criteria. However, typical isolated cortical hyperintensity of right temporal, parietal and occipital lobes on MRI suggested a probable CJD and prompted cerebral biopsy which confirmed the diagnosis. This article emphasises the need to update the current WHO criteria by including radiological findings.