FATAL FAMILIAL INSOMNIA

Insomnia Fatal Familial; FFI

Fatal Familial Insomnia (FFI) is a rare, genetic sleep disorder caused by prion mutation of the PRNP gene. These mutations lead to degeneration in the thalamus, the part of the brain responsible for sensory perception and regulation of motor function. FFI is characterized by by subacute onset of insomnia showing as a reduced overall sleep time, autonomic dysfunction, and motor disturbances.

Diagnostic testing:

• •

  Electroencephalography (EEG);

• •

  Magnetic resonance imaging (MRI) of the brain;

• •

  Sleep apnea testing; and

• •

  Evidence of mutations in the PRNP gene.

Physical findings:

• •

  Difficulty sleeping;

• •

  High pulse and blood pressure;

• •

  Excessive sweating; and

• •

  Decline in coordination and motor ability.

ICD-9: 046.72

FFI is a progressive sleep disorder that usually begins in adulthood and leads to death within 6 to 32 months.

There is no cure for FFI. Treatment is symptomatic and palliative.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation:

• •

  Clinical history and examination that describes the diagnostic features of this impairment; and

• •

  Appropriate laboratory testing, including genetic testing showing mutations in the PRNP gene.

Suggested Listings for Evaluation:

REMARKS