Creutzfeldt-Jakob disease (CJD) is caused by misfolded prion protein (PrPSc). The primary pathological hallmarks on brain histology are:

• A Lewy bodies (alpha-synuclein aggregates) in substantia nigra neurons
• B Senile plaques with amyloid-beta core and neurofibrillary tangles (tau)
• C Spongiform vacuolation (status spongiosus), neuronal loss, and reactive astrogliosis without inflammation ✓
• D Microglial nodules and neuronophagia with lymphocytic vasculitis

Explanation

Prion diseases (CJD, GSS, FFI, kuru) show the classic triad of spongiform vacuolation (cytoplasmic vacuoles in neurons and astrocytes giving a 'Swiss cheese' appearance to gray matter), progressive neuronal loss, and reactive astrocytic gliosis — all in the complete absence of inflammatory infiltrates (distinguishing prion disease from viral encephalitis). PrPSc deposits may form plaques (kuru plaques, florid plaques in variant CJD). Lewy bodies are the hallmark of Parkinson disease. Senile plaques and tangles define Alzheimer disease. Microglial nodules with neuronophagia characterize viral encephalitis.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.