A fatal familial insomnia patient initially misdiagnosed as Alzheimer’s disease: a case report

The key characteristics of FFI include insomnia and rapidly progressive dementia, its differential diagnosis with AD has been extensively discussed in clinical practice. This is the first report of FFI concerning Aβ and tau protein, raises the awareness that the ratio of p-tau/t-tau in cerebrospinal fluid can provide valuable diagnostic clues for FFI.