A brain biopsy of a patient shows the following as represented by a photomicrograph below.The most likely cause is ?
A. Creutzfeldt-Jakob Disease (CJD).
B. Brain abscess.
D. Hypothalamus degeneration.
Ans:A. Creutzfeldt-Jakob Disease
The photomicrograph shown above represents characteristic spongy change seen in cases of Creutzfeldt-Jakob Disease (CJD).
- It is an incurable and universally fatal neurodegenerative disease.Also called a human form of mad cow disease (bovine spongiform encephalopathy).
- CJD is caused by an infectious agent called a prion.
- Prions are misfolded proteins that replicate by converting their properly folded counterparts, in their host, to the same misfolded structure they possess.
- CJD causes the brain tissue to degenerate rapidly, and as the disease destroys the brain, the brain develops holes and the texture changes to resemble that of a kitchen sponge.
- Initially, intracytoplasmic vacuoles appear in neurons.
- As the disease progresses, vacuolization becomes more pronounced and the cortical neuropil develops a spongy appearance, hence the term spongiform encephalopathy.
- Advanced cases show neuronal loss, gliosis, and brain atrophy.
Cerebellar atrophy is usually severe.
- Unlike most cerebellar degenerations, there is more pronounced loss of granular neurons than Purkinje cells.
- There is no inflammation. The CSF is normal.
- The changes are confined to the gray matter (the primary pathology involves the neuronal body).