Neuropsychiatric issues, movement problems, and physiological effects can be the earliest symptoms as well.
The symptoms of fatal familial insomnia include:
The prognosis for fatal familial insomnia is not good.
It is a rapidly fatal disease with a mean duration of 18 months.
Verywell / Jessica Olah
Causes
This is usually a hereditary disease carried from parent to child through an autosomal dominant pattern.
Everyone who inherits the gene for fatal familial insomnia is expected to develop the disease.
Affected Areas of the Brain
Several regions of the brain are affected by fatal familial insomnia.
The area most commonly affected is the thalamus, which moderates communication between different regions of the brain.
This makes it impossible to achieve restful sleep.
Fatal Familial Insomnia Is a Prion Disease
Fatal familial insomnia is aprion disease.
A prion is a protein called PrPc, and its function is not known.
When it is folded in an abnormal shape, as in fatal familial insomnia, it is called PrPSc.
This gene is located on chromosome 20 in codons 178 and 129.
Diagnosis
This disease causes symptoms that are very noticeable.
Initially, however, it can be confused with conditions such as dementia, movement disorders, or psychosis.
Eventually, the unusual combination of symptoms along with a family history point to fatal familial insomnia.
Sleep studies and imaging tests may support the diagnosis, while genetic testing can confirm it.
There are a number of different tests you may undergo during your evaluation.
Polysomnography (Sleep Study)
You may have a sleep study if you complain of sleeping problems.
This is a non-invasive test that uses electrodes to measure electrical brain activity during sleep.
The electrodes are held into place on the scalp with adhesive.
An unusual fluctuation between sleep stages may be seen in fatal familial insomnia.
The brain waves may have an altered shape as well.
This study also measures breathing and muscle activity (of the arms and legs) during sleep.
This pattern involves a lack of deep sleep, unusual muscle movements, and excessive sounds during sleep.
These movements and sounds can also be seen with video monitoring.
It may show some abnormalities, including atrophy, which is shrinking of the brain.
Brain MRI in fatal familial insomnia can show signs of disease in many brain regions.
With fatal familial insomnia, PET can show evidence of decreased metabolism in the thalamus.
However, this test is not standard and is not available in most hospitals.
Treatment
There is no effective treatment that can reverse the disease or stop it from progressing.
Antipsychotics and medications used for movement disorders may be effective for a few days at a time.
Melatonin may help induce sleep, but it does not help in attaining deep sleep.
Previously, it has been suggested that doxycycline may have anti-prion effects.
All of the participants are receiving the medication and undergoing frequent assessment for early symptoms.
Preliminary results are due to be reported in about 10 years.
A Word From Verywell
Fatal familial insomnia is a devastating disease.
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