[Fatal familial insomnia: clinical, laboratory and pathological features]

Fatal familial insomnia (FFI) is a hereditary disease caused by prions and characterized by mutations in the gene of the prion protein. Its clinical, neuropathological and biomolecular properties make this a distinctive and worrying disorder.

We studied the clinical and laboratory findings of 14 patients belonging to three Italian and two French families. The genetic analysis done on all patients showed a mutation of codon 178 and polymorphism of codon 129 in both mutant and non-mutant alleles.

The signs and symptoms at the start of the disease were: changes in the sleeping-waking cycle, oniric episodes and frequent waking, dysautonomia, sphincter disorders and impotence in men, transitory diplopia and dysarthria, osteotendinous hyper-reflexia and myoclonias not associated with electroenchephalographic activity. The middle stages of the illness were associated with worsening of the oniric state, dysautonomia, dysarthria and dysphagia and the presence of pyramidal disorders. Finally the patient dies suddenly, either fully awake or following a final comatose state.

FFI, a disorder caused by prions, is a worrying illness. It is characterized by severe alteration in the sleep-waking cycle and other autonomic and endocrine circadian functions. It is still necessary to discover a treatment for this dramatic, invariably fatal disease, although considerable progress has been made since it was first described barely ten years ago.