Creutzfeldt-Jakob Disease in the Era of Diagnostic Triumph and Therapeutic Defeat: A Perspective from the Bedside.

Creutzfeldt-Jakob disease (CJD) exemplifies a cruel paradox of modern neurology: we can now diagnose it with near-perfect accuracy within hours, yet we cannot alter its invariably fatal course. The advent of cerebrospinal fluid (CSF) and skin real-time quaking-induced conversion (RT-QuIC), coupled with high-specificity brain MRI, has enabled robust ante-mortem diagnostic support for CJD, which was previously only definitively established post-mortem. Yet no disease-modifying therapy exists. Drawing on a molecularly supported case of sporadic CJD, this Perspective argues that the widening gap between diagnostic precision and therapeutic impotence is not merely a failure of prion medicine-it is a stress test for the entire rare-disease ecosystem. We examine how this diagnostic triumph creates an unprecedented opportunity for presymptomatic intervention, ultra-adaptive clinical trials, and synergistic combination therapies, and we propose a strategic roadmap to ensure that the next patient diagnosed within hours has a chance, however slim, of a different outcome.