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 (neurological symptoms) and these symptoms rapidly worsen in the space of a few months.
In variant CJD, symptoms that affect a person's behaviour and emotions (psychological symptoms) 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 protein (prion) that caused CJD.
Initial neurological symptoms of sporadic CJD can include:
- difficulty walking caused by problems with balance and co-ordination
- slurred speech
- numbness or pins and needles in different parts of the body
- vision problems, such as double vision
- hallucinations (seeing or hearing things that aren't really there)
Initial psychological symptoms of variant CJD can include:
- severe depression
- withdrawal from family, friends and the world around you
- difficulty sleeping (insomnia)
Advanced neurological symptoms of all forms of CJD can include:
- loss of physical co-ordination, which can affect a wide range of functions, such as walking, speaking and balance (ataxia)
- muscle twitches and spasms
- loss of bladder control (urinary incontinence) and bowel control (bowel incontinence)
- swallowing difficulties (dysphagia)
- loss of speech
- loss of voluntary movement
Advanced psychological symptoms of all forms of CJD include:
- loss of memory, which is often severe
- problems concentrating
- feeling agitated
- aggressive behaviour
- loss of appetite, which can lead to weight loss
- unusual and inappropriate emotional responses
As the condition progresses to its final stages, people with all forms of CJD will become totally bedridden.
They often become totally unaware of their surroundings and require around-the-clock care.
They also often lose the ability to speak and can't communicate with their carers.
Death will inevitably follow, usually either as a result of an infection, such as pneumonia, or respiratory failure, where the lungs stop working and the person is unable to breathe.
Nothing can be done to prevent death in these circumstances.
Advancements in end of life care (the treatment of incurable conditions) mean that people with CJD often have a peaceful death.
Read more about treating Creutzfeldt-Jakob disease.