Understanding Creutzfeldt-Jakob Disease (CJD) By: Nichole Michael-Avabore

Introduction

Creutzfeldt-Jakob disease (CJD) is a rare, rapidly

progressive, and always fatal neurodegenerative disorder.

It belongs to a family of diseases known as prion diseases,

also called Transmissible Spongiform Encephalopathies

(TSEs). Spongiform refers to the way affected brains look.

With prion diseases, the brain is filled with holes and looks

like a sponge when the tissue is examined under a

microscope. Like other prion diseases, CJD causes

problems with muscle coordination, thinking, and memory.

There are about 350 cases per year in the United States,

and about 70% of people with CJD die within one year of

getting the disease.

Why Is It Important?

It is vital to understand CJD because it is rare, and

although it isn’t very well known, it is universally fatal.

Many people struggle with dementia, problems with

thinking, balance problems, etc. As of now, there is no

known cure; thus, research is vital for developing early

diagnostic tests and effective treatments.

Who It Affects

CJD doesn’t heavily favour any specific gender or race;

however, in terms of age range, it depends entirely on the

specific type of the disease. Sporadic CJD primarily strikes

older adults while Variant CJD targets young adults.

Additionally, Iatrogenic CJD, which is acquired

accidentally through contaminated medical or surgical

procedures, can affect any age, including children,

depending entirely on when the medical exposure

occurred.

Causes

Creutzfeldt-Jakob disease (CJD) is caused by an abnormal

infectious protein in the brain called a prion. Proteins are

molecules made up of amino acids that help the cells in our

body function. They begin as a string of amino acids that

then fold themselves into a 3-dimensional shape. This

"protein folding" allows them to perform useful functions

within our cells. Normal (harmless) prion proteins are

found in almost all body tissues, but are at the highest

levels in brain and nerve cells. The exact role of normal

prion proteins is unknown, but it's thought they may play a

role in transporting messages between certain brain cells.

Mistakes sometimes occur during protein folding, and the

prion protein can't be used by the body. Normally, these

misfolded prion proteins are recycled by the body, but they

can build up in the brain if they aren't recycled.

How prions cause CJD

Prions are misfolded prion proteins that build up in the

brain and cause other prion proteins to misfold as well.

This causes the brain cells to die, releasing more prions to

infect other brain cells. Eventually, clusters of brain cells

are killed, and deposits of misfolded prion protein called

plaques may appear in the brain. Prion infections also

cause small holes to develop in the brain, so it becomes

sponge-like. The damage to the brain causes the mental

and physical impairment associated with CJD, and

eventually leads to death. Prions can survive in nerve

tissue, such as the brain or spinal cord, for a very long

time, even after death.

Types of CJD

The different types of CJD are all caused by a build-up of

prions in the brain. But the reason why this happens is

different for each type. Sporadic CJD: it occurs

spontaneously for no apparent reason, and most frequently

affects older adults between 50 and 80 years old. It

progresses extremely rapidly, often leading to death within

4 to 6 months.

Variant CJD: caused by the same strain of prions that

causes Bovine Spongiform Encephalopathy (BSE, or "mad

cow" disease). Uniquely targets young adults and moves

slightly slower than Sporadic CJD, with patients surviving

an average of 13 to 14 months.

Familial or inherited CJD: caused by an inherited mutation

in the gene that produces the prion protein. It is inherited

in an autosomal dominant pattern, meaning a child of a

carrier has a 50% chance of inheriting it.

Iatrogenic CJD: transmission occurs through contaminated

medical or surgical procedures. Can affect any age group

depending on when the medical exposure took place.

Is CJD contagious?

In theory, CJD can be transmitted from an affected person

to others, but only through an injection or consuming

infected brain or nervous tissue. There's no evidence that

sporadic CJD is spread through ordinary day-to-day

contact with those affected or by airborne droplets, blood

or sexual contact. But in the UK, variant CJD has been

transmitted on 5 occasions by blood transfusion.

Symptoms

The pattern of symptoms can vary depending on the type

of Creutzfeldt-Jakob disease (CJD). In Sporadic CJD, the

symptoms mainly affect the workings of the nervous

system, and these symptoms rapidly worsen in the space of

a few months. In Variant CJD, symptoms that affect a

person's behaviour and emotions will usually develop first.

These are then followed by neurological symptoms around

4 months later, which get worse over the following few

months. Familial CJD has the same sort of pattern as

sporadic CJD, but it often takes longer for the symptoms to

progress – usually around 2 years, rather than a few

months. The pattern of Iatrogenic CJD is unpredictable, as

it depends on how a person became exposed to the

infectious prion that caused CJD.

Diagnosis

Discovering that someone has CJD is historically and

clinically very difficult, especially in the initial stages.

Studies show that only about 18% of CJD patients are

correctly diagnosed upon their first medical assessment.

The average patient receives four misdiagnoses and often

goes through two-thirds of their short disease course

before getting a correct answer. While a 100% definitive

diagnosis requires an autopsy after death, a clinical

neurologist can use advanced tests such as an MRI brain

scan to diagnose a probable case with incredible accuracy

while the patient is still alive. Other tests include: an EEG,

a Lumbar Puncture, a Prototype Blood Test, a Tonsil

Biopsy, etc.

Treatment

As of now, there is no proven cure for Creutzfeldt-Jakob

disease; however, there are ways people can manage it.

Treatment involves trying to keep the person as

comfortable as possible and reducing symptoms with

medicines. For example, psychological symptoms of CJD,

such as anxiety and depression, can be treated with

sedatives and antidepressants, and muscle jerks or tremors

can be treated with medicines like clonazepam and sodium

valproate. During later stages of the disease, people may

need IV fluids and machine feeding, but because CJD and

other prion diseases are incurable, these approaches can

have limited use. Towards the end of their life, people with

CJD may receive hospice services.

Current Research

Research into CJD is currently moving away from simple

symptom management and towards therapies that block or

lower the production of prion proteins. Although it’s

considered untreatable, CJD research now focuses on

non-invasive detection methods and the identification of

disease-modifying therapies to target the rogue prions that

cause the disease.

Life With CJD

Living with CJD is a deeply intense experience as the

disease progresses in weeks rather than years. For the

individual and their family, day-to-day life shifts from

managing subtle changes to providing full care. In the

early stages, the patient begins to lose their independence,

often not being able to perform daily tasks such as

cooking, driving, or working due to sudden vision changes

or sudden clumsiness. Walking also becomes unsteady,

requiring the use of canes, walkers, and assistance on stairs

to prevent falls. During the middle stage, the disease strips

away physical autonomy, meaning the individual requires

full-time caregiving. Patients usually lose the ability to

walk or stand, and they often permanently transition to a

wheelchair or bed. Involuntary muscle jerks also occur

frequently, and loud noises or sudden touch can startle the

patient or trigger spasms; thus, a quiet home environment

is required. In the advanced stage, the individual generally

loses awareness of their surroundings and can no longer

speak; therefore, life narrows down to bedside palliative

comfort.

Statistics

CJD affects roughly 1 to 2 individuals per million people

annually worldwide. In the United States, this equates to

roughly 500 to 600 cases diagnosed each year. In the

United Kingdom, it accounts for roughly 100 to 130

annual. CJD remains rare enough that it is responsible for

only about 1 out of every 6,000 to 10,000 total deaths in

the U.S. annually. The standard median survival rate after

formal diagnosis or the presentation of clinical symptoms

is 4 to 6 months. Roughly 70% to 90% of individuals

diagnosed succumb to the illness within 12 months of

symptom onset. Long-term survival beyond two years

occurs in less than 10% of cases, usually associated with

specific genetic mutations or atypical variations of the

disease.

Why Awareness Matters

Awareness of CJD is a critical matter because it is a rare,

hidden disease that destroys the brain in a matter of weeks,

so raising awareness directly saves lives and protects

families from devastating isolation. People need to learn

about CJD because it prevents misdiagnosis; early CJD

mimics depression or just typical aging, so the vast

majority of patients are initially misdiagnosed, which leads

to delayed treatment, putting the patient in more pain as

their symptoms will only get worse and become

unbearable. Furthermore, it also protects public health as

prions are nearly indestructible and they often cling to

medical equipment. Therefore, by making the public aware

of this, hospitals can ensure they follow strict sterilization

protocols, preventing accidental transmissions during brain

surgeries.

Conclusion

CJD may remain a rare illness, but its impact is significant.

By recognising that it’s caused by prions, early recognition

and treatment can become more common, and by

understanding its symptoms and their pattern, healthcare

professionals and carers can play a crucial role in ensuring

misdiagnosis doesn’t happen and can ensure patients

receive timely and effective care. Increasing awareness is

therefore essential in reducing misdiagnosis and

safeguarding long-term health.

Sources

1. National Institute of Neurological Disorders and

Stroke (NINDS):

https://www.ninds.nih.gov/health-information/disorde

rs/creutzfeldt-jakob-disease

2. National Health Service (NHS):

https://www.nhs.uk/conditions/creutzfeldt-jakob-disea

se-cjd/treatment/

3. National CJD Research & Surveillance Unit

(NCJDRSU):

https://cjd.ed.ac.uk/sites/default/files/2025-01/Latest%

20NCJDRSU%20annual%20report%2C%20covering

%20the%20period%201990-2023.pdf

4. CDC:

https://www.cdc.gov/creutzfeldt-jakob/hcp/clinical-ov

erview/index.html#cdc_clinical_overview_resources-r