Cerebral hypermetabolism demonstrated by FDG PET in familial Creutzfeldt-Jakob disease

Right cerebral and contralateral cerebellar hypermetabolism were observed on FDG PET in a 68-year-old woman with familial Creutzfeldt-Jakob disease (CJD) at an early stage before seizures occurred. The disease progressed with frequent seizures, myoclonus, and a startle reaction. In all past reports, FDG PET studies demonstrated hypometabolism in the cerebrum, cerebellum, and thalamus in patients with CJD. Focal hypermetabolism corresponding with epileptic foci is a common finding in ictal epilepsy patients, and hypometabolism is common in patients with myoclonus or the startle reaction. This finding may reflect a prodromal pathophysiology of epilepsy. Attention should be paid to the diagnosis of CJD while using FDG PET.