A 50-year-old immunocompetent patient develops rapidly progressive dementia with myoclonus, and periodic sharp-wave complexes on EEG. Brain MRI shows cortical ribboning on DWI sequences. CSF real-time quaking-induced conversion (RT-QuIC) test is positive. What is the pathological hallmark of this condition?
- A Intraneuronal Pick bodies composed of 3-repeat tau protein
- B Neurofibrillary tangles with beta-amyloid plaques in hippocampus and neocortex
- C Spongiform vacuolation of the cerebral cortex with PrPSc deposition ✓
- D Demyelination with reactive gliosis and Dawson finger lesions
Explanation
Sporadic Creutzfeldt-Jakob disease (CJD) is the most common human prion disease, characterized neuropathologically by spongiform vacuolation (small vacuoles in the neuropil, giving a sponge-like appearance), neuronal loss, reactive astrogliosis, and deposition of disease-causing prion protein (PrPSc). RT-QuIC is a highly sensitive and specific CSF test that amplifies the prion-seeding activity of misfolded PrPSc, now considered a diagnostic criterion. Cortical ribboning on DWI MRI reflects restricted diffusion in areas of spongiform change. The disease is uniformly fatal within months. Pick bodies (3R tau) characterize Pick disease; demyelination characterizes MS.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.