A longitudinal 18F‐FDG PET study in asymptomatic stage of genetic Creutzfeldt–Jakob disease

Abstract

AbstractBackgroundPathogenic prion protein may start to deposit in some brain regions and cause functional alterations in the asymptomatic stages in Creutzfeldt–Jakob disease patients. However, the disease trajectory of Creutzfeldt–Jakob disease in the asymptomatic stage and when and where the degenerative process begins are still not clear.MethodsAt baseline, we enrolled five asymptomatic mutation carriers, six affected genetic Creutzfeldt–Jakob diseasepatients, and 23 healthy controls from whom 18F fluorodeoxyglucose‐positron emission tomography, clinical, and neuropsychological measures were acquired. Only five asymptomatic mutation carriers had completed longitudinal follow‐up. We set three‐time points to identify the changing trajectory in asymptomatic carriers group including baseline, 2‐year and 4‐year follow‐up.ResultsAt baseline, the cerebral glucose metabolic rate, measured as the standardized uptake value rate ratio, clinical and neuropsychological scales in all 5 asymptomatic cases were normal. In the 4‐years follow‐up, hypometabolic brain regions in asymptomatic genetic Creutzfeldt–Jakob disease group were found in the insula, frontal, parietal, and temporal lobes (false discovery rate corrected p<0.01). The standardized uptake value rate ratio changing trajectories of all asymptomatic cases were within the range between the healthy controls and affected patients. Notably, the metabolism values of one asymptomatic individual whose baseline age was older than the expected age of onset showed a rapid decline and approached the mean value of genetic Creutzfeldt–Jakob disease condition at the last follow‐up.ConclusionOur study illustrates that neurodegenerative process associated with genetic Creutzfeldt–Jakob disease may involve the insula, frontal, temporal, and parietal lobes before clinical presentation of the disease, and the decline will accelerate when close to the expected age of onset. Although there are no effective means to cure this fatal disease, the time interval before clinical disease onset may aid important trials or therapies intended to slow or halt the disease process.