Summary about Disease
Creutzfeldt-Jakob disease (CJD) is a rare, rapidly progressive, and fatal neurodegenerative disease that belongs to a group of disorders known as prion diseases or transmissible spongiform encephalopathies (TSEs). CJD is characterized by the accumulation of abnormal prion proteins in the brain, leading to widespread neuronal damage and a variety of neurological and psychiatric symptoms. It is not caused by a virus or bacteria. There are several forms of CJD: sporadic (the most common), familial (genetic), and acquired (very rare, usually through medical procedures).
Symptoms
Symptoms of CJD vary but often include:
Rapidly developing dementia
Difficulty with coordination and balance (ataxia)
Muscle stiffness, twitches, and spasms (myoclonus)
Vision problems (blurred vision or blindness)
Difficulty speaking (dysarthria)
Swallowing difficulties (dysphagia)
Personality changes
Anxiety and depression
Insomnia
Causes
CJD is caused by infectious, misfolded proteins called prions. These prions cause normal prion proteins to misfold, leading to a chain reaction that damages the brain. The causes vary by type:
Sporadic CJD: The cause is unknown; the prion protein spontaneously misfolds.
Familial CJD: Caused by inherited genetic mutations in the prion protein gene (PRNP).
Acquired CJD: Results from exposure to prion-contaminated material, usually through medical procedures (e.g., contaminated surgical instruments, corneal transplants, or dura mater grafts). Variant CJD (vCJD) is a form acquired by eating beef from cattle infected with bovine spongiform encephalopathy (BSE, or mad cow disease).
Medicine Used
There is no cure for CJD, and no medications can stop its progression. Treatment focuses on managing symptoms and providing supportive care. Medications used may include:
Pain relievers (for pain)
Antidepressants (for depression and anxiety)
Muscle relaxants (for myoclonus/muscle spasms)
Anti-seizure medications (for seizures, if they occur)
Is Communicable
CJD is not contagious through normal contact, such as touching or being near someone who has the disease. However, acquired CJD can be transmitted through contaminated medical equipment or tissues. Variant CJD can be transmitted through blood transfusions (rare).
Precautions
Precautions are mainly relevant in healthcare settings to prevent iatrogenic (acquired) CJD:
Strict Sterilization: Surgical instruments used on patients with suspected or confirmed CJD require rigorous sterilization procedures that go beyond standard autoclaving. Some instruments may be disposable.
Tissue Handling: Handling of brain tissue and spinal fluid from suspected CJD cases requires special precautions in laboratories and during autopsies.
Blood Donations: People with a family history of CJD, those who have received dura mater grafts, or who have lived in the UK during the BSE outbreak may be restricted from donating blood.
Variant CJD: Preventative measures related to vCJD focus on the beef supply and restricting blood donations from individuals at risk.
How long does an outbreak last?
CJD is not an outbreak-driven disease like influenza or measles. It generally occurs as sporadic cases. vCJD has occurred in clusters, but these are more accurately described as limited epidemics. Sporadic CJD cases arise independently, with no defined outbreak duration. The lifespan of a person after diagnosis averages about 6 months.
How is it diagnosed?
Diagnosis of CJD can be challenging, especially in the early stages. It typically involves a combination of:
Neurological Examination: Assessing symptoms and neurological function.
Electroencephalogram (EEG): To look for characteristic brain wave patterns.
Magnetic Resonance Imaging (MRI): Brain scans to identify specific patterns of brain damage.
Cerebrospinal Fluid (CSF) Analysis: Testing the CSF for specific markers, such as 14-3-3 protein, total tau protein, or real-time quaking-induced conversion (RT-QuIC) assay for prion detection. RT-QuIC is highly sensitive and specific.
Genetic Testing: To check for mutations in the PRNP gene in suspected cases of familial CJD.
Brain Biopsy or Autopsy: Rarely performed while the patient is alive, but autopsy is the only way to definitively confirm CJD by examining brain tissue for prion deposits.
Timeline of Symptoms
The progression of CJD varies, but typically it is rapid:
Early Stages: Subtle memory problems, personality changes, coordination difficulties.
Mid Stages: Worsening dementia, myoclonus, visual disturbances, speech problems.
Late Stages: Severe dementia, immobility, loss of speech, coma.
Overall: The disease typically progresses over a few months to a year, with death usually occurring within that timeframe.
Important Considerations
Rarity: CJD is a very rare disease, with an incidence of about one case per million people per year.
Rapid Progression: The rapid decline in cognitive and motor function is a hallmark of CJD.
Fatal Outcome: CJD is invariably fatal.
Differential Diagnosis: It is important to rule out other conditions that can mimic CJD symptoms, such as Alzheimer's disease, stroke, and other neurological disorders.
Supportive Care: Focusing on providing comfort and support to the patient and their family is crucial.