Sporadic fatal insomnia in a young woman: a diagnostic challenge: case report

BMC Neurol. 2011 Oct 31;11:136. doi: 10.1186/1471-2377-11-136.


Background: Sporadic fatal insomnia (sFI) and fatal familial insomnia (FFI) are rare human prion diseases.

Case presentation: We report a case of a 33-year-old female who died of a prion disease for whom the diagnosis of sFI or FFI was not considered clinically. Following death of this patient, an interview with a close family member indicated the patient's illness included a major change in her sleep pattern, corroborating the reported autopsy diagnosis of sFI. Genetic tests identified no prion protein (PrP) gene mutation, but neuropathological examination and molecular study showed protease-resistant PrP (PrPres) in several brain regions and severe atrophy of the anterior-ventral and medial-dorsal thalamic nuclei similar to that described in FFI.

Conclusions: In patients with suspected prion disease, a characteristic change in sleep pattern can be an important clinical clue for identifying sFI or FFI; polysomnography (PSG), genetic analysis, and nuclear imaging may aid in diagnosis.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Atrophy / pathology
  • Brain / metabolism
  • Brain / pathology*
  • Female
  • Humans
  • Insomnia, Fatal Familial / diagnosis*
  • Insomnia, Fatal Familial / genetics
  • Insomnia, Fatal Familial / metabolism
  • Insomnia, Fatal Familial / pathology*
  • Mutation
  • PrPSc Proteins / metabolism*
  • Prions / genetics
  • Prions / metabolism
  • Thalamic Nuclei / pathology*


  • PrPSc Proteins
  • Prions