A meta-analysis on RT-QuIC for the diagnosis of sporadic CJD

Creutzfeld–Jakob disease (CJD) is a fatal neurodegenerative disease which belongs to the family of transmissible spongiform encephalopathies (TSEs), or prion diseases. Historically, CJD diagnosis has been based on the combination of clinical features and in vivo markers, including CSF protein assays, MRI and EEG changes. Brain-derived CSF proteins, such as 14-3-3, t-tau and p-tau have been largely used to support the diagnosis of probable CJD, although with certain limitations concerning sensitivity and specificity of these tests. More recently, a new method for the pre-mortem diagnosis of sporadic CJD has been developed, based on the ability of PrPsc to induce the polymerization of protease-sensitive recombinant PrP (PrPsen) into amyloid fibrils, and is known as Real-Time Quaking- Induced Conversion (RT-QuIC) assay allows the detection of > 1 fg of PrPsc in diluted CJD brain homogenate and a variety of biological tissues and fluids. In the present study, we did a meta-analysis on the liability of RT-QuIC method in the diagnosis of sporadic CJD, in comparison to 14-3-3 and Tau protein. Twelve studies were finally included in the statistical analysis which showed that RT-QuIC has a very high specificity and comparable sensitivity to 14-3-3 protein and Tau protein in the CSF, and hence can be used as a reliable biomarker for the diagnosis of sporadic CJD.