Prion Diseases Overview

What is the average duration from the first symptoms to death in sporadic Creutzfeldt-Jakob Disease (sCJD)?

Which of the following is a presenting symptom of prion diseases?

What is the main cause of inherited prion disease (IPD)?

Which diagnostic tool has a 90-95% accuracy rate for detecting sporadic Creutzfeldt-Jakob Disease (sCJD)?

What type of prion disease is characterized by an onset age ranging from the 20s to 80s?

Which statement accurately describes the cellular prion protein (PrP^c^)?

What is the typical end-stage condition seen in patients with sporadic Creutzfeldt-Jakob Disease (sCJD)?

How does an error in the DNA code contribute to inherited prion diseases (IPD)?

Which of the following is NOT a common presenting symptom of prion diseases?

What is the primary way in which acquired CJD is transmitted?

Prion Diseases

Prion diseases, also known as transmissible spongiform encephalopathies (TSEs), are a group of rare, progressive neurodegenerative disorders.
Sporadic Creutzfeldt-Jakob Disease (sCJD) is the most common type, affecting about 85% of cases
sCJD has an average onset age of 65 and typically progresses to akinetic mutism within 4-6 months.
Inherited Prion Disease (IPD) accounts for 10-15% of cases
IPD onset can range from the 20s to 80s and persists for 2 to 20 years.
Acquired CJD is a rare form (<1%) caused by factors like medication, meat, surgical procedures, and blood transfusions.

Cellular Prion Protein (PrP^C)

The PRNP gene provides instructions to produce the normal cellular prion protein (PrP^C).
PrP^C helps protect and enable communication between brain cells.
Misfolding of PrP^C into PrP^Sc causes prion diseases.
Prion diseases are self-amplifying, with misfolded proteins causing more misfolding.
Abnormal prion proteins are resistant to enzymes, form aggregates, show conformational changes, and lead to spongiform degeneration of the brain tissue.

Presenting Symptoms

Myoclonus (jerky movements)
Vision problems
Impairment in thinking and planning
Cognitive impairment (affecting memory, attention, and executive function)
Language difficulties (dysphasia, dysarthria)
Behavioral changes (agitation, anxiety)
Sleep disturbances
Hallucinations

Investigations for sCJD

MRI brain scans are highly accurate (90-95%).
Blood tests can identify genetic prion diseases.
Electroencephalograms (EEG) provide less accurate assessment of brain waves (40-50%).
Lumbar punctures (spinal fluid analysis) are highly accurate (>95%) in diagnosing sCJD.

This quiz delves into the complexities of prion diseases, including their types, causes, and cellular mechanisms. Learn about sporadic and inherited forms, as well as the role of the PRNP gene in these neurodegenerative disorders. Test your knowledge on the impact of misfolded proteins and disease progression.