PrPTSE detection

In vivo diagnosis of definite CJD

Olfactory mucosa brushing coupled with RT-QuIC: a potential and innovative test for intravital definite diagnosis of Creutzfeldt-Jakob disease

2013: 1 year

Subvention: 34 000 euros

Project: The project “In vivo diagnosis of definite CJD” proposed to develop, evaluate and validate an innovative prion diagnosis method combining RT-QuIC PrPTSE detection, which has been shown to be really sensitive, with the non-invasive procedure of nasal brushing designed to obtain olfactory mucosalcells. Since olfactory mucosa (OM) had previously been shown to propagate prion during the development of the pathology, this tissue seemed to represent a good target for PrPTSE detection.

Main results and related published data: The method proposed by G. Zanusso was successful, as reported in numerous subsequent articles. The use of nasal brushing material to seed in RT-QuIC assays,showed positive signalsin 100% ofconfimed CJD, 92% of probable CJD and 100% of genetic CJD and no false positives. The globalsensitivity and specificity were evaluated and were 97% and 100% respectively. This is quite stronger than the results obtained using CSF samples to seed the RT-QuIC assay (77% of sensititvity and 100% of specificity). In a recent publication, by combining PrPTSE detection using RT-QuIC assayin OM, CSF, or both, it was possible to improve the sensitivity.
They therefore proposed a diagnostic algorithm for sporadic CJD, combining CSF and OM RT-QuIC analysis, which is expected to be of strong relevance for the diagnosis of sporadic CJD.