Fatal Familial Insomnia (FFI)

Overview

Fatal Insomnia is a prion disease with symptoms including insomnia, mental deterioration, and loss of coordination.  It predominantly affects the thalamus.  Fatal Familial Insomnia (FFI) is inherited.  Sporadic Fatal Insomnia (SFI) occurs spontaneously.

Symptoms

Typical early symptoms: severe insomnia that continues to worsen, accompanied by ataxia (inability to coordinate movements) and mental confusion.

Dementia and weight loss increase over time.  

May also include excessive sweating, unsteady gait, jerky eye movements, double vision, dysarthria, high blood pressure, hyperventilation, excessive tearing, hallucinations, panic.

Type

Generally genetic (with rare cases of Sporadic Fatal Insomnia)

Occurrence

At least 25 known families, rarest genetic prion disease

Duration

A few months to 5 years

Age of onset

Mid-life, typically 30s, 40s, 50s

Diagnosis

Clinical examination, family history, genetic testing, polysomnography (sleep study) and positron emission tomography, spinal fluid testing (RT-QuIC). Fatal Insomnia, particularly sFI, is confirmed by autopsy.  (Contact the CJD Foundation for specifics).

Mutation

D178N-129M

 

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