Related Experiment Video
Updated: Aug 5, 2026
Quantifying Infra-slow Dynamics of Spectral Power and Heart Rate in Sleeping Mice
Published on: August 2, 2017
Sporadic fatal insomnia: a case study
F Scaravilli1, R J Cordery, H Kretzschmar
1Department of Neuropathology, Institute of Neurology, University College London, UK.
Abstract:
A 58-year-old man died after a 27-month illness characterized by insomnia, confirmed by polysomnography. He was homozygous for methionine at codon 129 of the prion gene but had no mutation in the prion gene. Neuropathology showed thalamic and olivary atrophy and no spongiform changes. Paraffin-embedded tissue blotting demonstrated abnormal prion protein in the brain. This is the first case of the sporadic form of fatal familial insomnia with demonstration of the disorder by polysomnography.
Insights
This study details the first sporadic fatal insomnia case diagnosed via polysomnography. The patient showed no prion gene mutation but had abnormal prion protein, confirming a rare form of insomnia.
Area of Science:
- Neurology
- Neuroscience
- Genetics
Background:
- Fatal familial insomnia (FFI) is a rare, fatal prion disease.
- It is typically characterized by a genetic mutation in the prion gene (PRNP).
- Sporadic forms are exceptionally rare and poorly understood.
Purpose of the Study:
- To report the first case of sporadic fatal insomnia (sFFI) diagnosed using polysomnography.
- To characterize the clinical, genetic, and neuropathological findings of this rare case.
- To highlight the utility of polysomnography in diagnosing prion diseases.
Main Methods:
- Clinical case presentation of a 58-year-old man with a 27-month illness.
- Polysomnography to confirm severe insomnia.
- Genetic analysis of the prion gene (PRNP) for mutations.
- Neuropathological examination including paraffin-embedded tissue blotting for abnormal prion protein detection.
Main Results:
- The patient exhibited severe insomnia confirmed by polysomnography.
- Genetic analysis revealed homozygosity for methionine at codon 129 of the PRNP gene, but no pathogenic mutation.
- Neuropathology showed thalamic and olivary atrophy without spongiform changes.
- Abnormal prion protein was detected in the brain via paraffin-embedded tissue blotting.
Conclusions:
- This case represents the first documented instance of sporadic fatal insomnia diagnosed with polysomnography.
- The findings suggest that sFFI can occur without PRNP mutations and present with distinct neuropathological features.
- Polysomnography is a valuable tool for the diagnosis of severe sleep disturbances in prion diseases.
