1/7. Serial positron emission tomographic findings in an atypical presentation of fatal familial insomnia.BACKGROUND: Genetic analyses of fatal familial insomnia, a prion disease, disclose a broader range of symptoms than previously described. Although insomnia and dysautonomia have been described as hallmarks of the disease, there is substantial variability in clinical presentation. OBJECTIVE: To evaluate serial fluorodeoxyglucose positron emission tomographic and electroencephalographic findings in atypical fatal familial insomnia without clinical insomnia. PATIENT: A 63-year-old man who had a history of gait ataxia developed rapidly progressive dementia with mild dysautonomic features. Genetic investigation confirmed diagnosis of fatal familial insomnia (D178N mutation of the prion protein gene and Val/Met polymorphism on position 129 of the mutated allele) with typical neuropathologic findings. RESULTS: Clinical signs were not specific. An electroencephalogram showed scanty triphasiclike elements and general slowing. We found thalamic hypometabolism in positron emission tomographic scans to be present in a very early stage with progressive deterioration, and patchy cortical alterations showing progression over 6 months. CONCLUSIONS: In the absence of clear clinical signs, an electroencephalogram was of major diagnostic value, although its specificity in fatal familial insomnia is under debate. Selective thalamic hypometabolism seems to be an early marker in fatal familial insomnia, while cortical changes vary with clinical presentation and stage. ( info) |
2/7. Fatal familial insomnia: the first account in a family of Chinese descent.BACKGROUND: Fatal familial insomnia (FFI) is an autosomal dominant disease linked to a mutation in the prion protein gene. Fatal familial insomnia is characterized by sleep disturbance and loss of neurons, with gliosis in the thalamic nuclei. OBJECTIVE: To describe the clinical, neurophysiological, radiological, and neuropathological data in a Chinese family with FFI. SETTING: Tertiary referral university hospital setting. patients: Patient 1 was a 36-year-old man who presented with insomnia and myoclonus. In the subsequent 9 months, he developed ataxia and dementia, followed by death. Patient 2 was the aunt of patient 1, and presented at the age of 47 years with insomnia, myoclonus, and dementia; her condition declined during a 12-month period. Genetic analysis was performed, followed by neuropathological and biochemical analysis of the disease-associated form of the prion protein PrPSc on the postmortem brain specimen. RESULTS: Molecular analysis demonstrated an aspartic acid to asparagine mutation at codon 178 and homozygosity for methionine at codon 129. Both patients showed severe neuronal loss and prominent gliosis in the thalamus and brainstem involvement, with evidence of astrogliosis in the inferior olivary nucleus. Patient 1 also had neuronal loss and astrogliosis in the region of the superior colliculus and in the periaqueductal region. PrPSc was detected on Western blot analysis, and had a wide distribution. The strongest signals were present in the amygdala, hypothalamus, caudate, parahippocampal gyrus, periaqueductal gray matter, and mediodorsal thalamus. CONCLUSIONS: To our knowledge, this is the first report of FFI in a family of Chinese descent. This supports the worldwide distribution of FFI, and despite differences in genetic background, the clinical and pathological findings are similar to those found in white patients with FFI. ( info) |
3/7. Combined quinacrine and chlorpromazine therapy in fatal familial insomnia.prion diseases are invariably fatal. Recently, quinacrine and chlorpromazine have been suggested as immediate candidates for the treatment of Creutzfeldt-Jakob disease and other prion diseases. The objective of this paper was to report on 2 fatal familial insomnia patients whose overall condition worsened despite quinacrine and chlorpromazine treatment. ( info) |
4/7. Dissociation in circadian rhythms in a pseudohypersomnia form of fatal familial insomnia.The authors present clinical, sleep, and neuroendocrine features of a patient with genetically confirmed fatal familial insomnia (D178N mutation with heterozygosity at codon 129 of the prion protein gene). The patient exhibited pseudohypersomnia behavior instead of insomnia. There was profound alteration in the sleep-wake cycle with a clear dissociation in the disappearance of circadian and neuroendocrine rhythms, findings unrelated to abnormalities in the hypocretinergic system. ( info) |
5/7. Fatal familial insomnia with an unusual prion protein deposition pattern: an autopsy report with an experimental transmission study.We recently performed a post-mortem examination on a Japanese patient who had a prion protein gene mutation responsible for fatal familial insomnia (FFI). The patient initially developed cerebellar ataxia, but finally demonstrated insomnia, hyperkinetic delirium, autonomic signs and myoclonus in the late stage of the illness. Histological examination revealed marked neuronal loss in the thalamus and inferior olivary nucleus; however, prion protein (PrP) deposition was not proved in these lesions by immunohistochemistry. Instead, PrP deposition and spongiform change were both conspicuous within the cerebral cortex, whereas particular PrP deposition was also observed within the cerebellar cortex. The abnormal protease-resistant PrP (PrP(res)) molecules in the cerebral cortex of this case revealed PrP(res) type 2 pattern and were compatible with those of FFI cases, but the transmission study demonstrated that a pathogen in this case was different from that in a case with classical FFI. By inoculation with homogenate made from the cerebral cortex, the disease was transmitted to mice, and neuropathological features that were distinguishable from those previously reported were noted. These findings indicate the possibility that a discrete pathogen was involved in the disease in this case. We suggest that not only the genotype of the PrP gene and some other as yet unknown genetic factors, but also the variation in pathogen strains might be responsible for the varying clinical and pathological features of this disease. ( info) |
6/7. Sporadic fatal insomnia with spongiform degeneration in the thalamus and widespread PrPSc deposits in the brain.We report a case of human prion disease of 29 months duration in a 74-year-old Japanese man. The disease started with progressive sleeplessness and dementia. MRI showed gradually progressive cerebral atrophy. Neuronal loss, spongiform change and gliosis were evident in the thalamus and cerebral cortex, as well as in the striatum and amygdaloid nucleus. In the cerebellar cortex, mild-to-moderate depletion of Pukinje cells and spongiform change were observed. Mild neuronal loss in the inferior olivary nucleus was also seen. immunohistochemistry revealed widespread perivacuolar deposits of abnormal prion protein (PrPsc) in the cerebral cortex, thalamus, basal ganglia, and brainstem, and minimal plaque-like deposits of PrPSc in the cerebellar cortex. In the cerebellar plaque-like deposits, the presence of amyloid fibrils was confirmed ultrastructurally. The entire pathology appeared to lie halfway between those of CJD and fatal insomnia, and further demonstrated the relationship between spongiform degeneration and PrPSc deposits, especially in the diseased thalamus. By immunoblotting, the thalamus was shown to contain the lowest amount of PrPSc among the brain regions examined. The PrPSc of type 2, in which the ratio of the three glycoforms was compatible with that of sporadic fatal insomnia (MM2-thalamic variant) reported previously, was also demonstrated. Analysis of the prion protein gene (PRNP) showed no mutation, and homozygosity for methionine at codon 129. In conclusion, we considered that this patient had been suffering from sporadic, pathologically atypical fatal insomnia. ( info) |
7/7. Fatal familial insomnia: a model disease in sleep physiopathology.Fatal Familial Insomnia (FFI) is characterized by loss of sleep, oneiric stupor with autonomic/motor hyperactivity and somato-motor abnormalities (pyramidal signs, myoclonus, dysarthria/dysphagia, ataxia). Positon emission tomography (PET) disclosed thalamic hypometabolism and milder involvement of the cortex; neuropathology severe neuronal loss in the thalamic nuclei variably affecting the caudate, gyrus cinguli and fronto-temporal cortices. Genetic analysis disclosed a mutation in the PRNP gene and FFI was transmitted to experimental animals, thus classifying FFI within the prion diseases. Rare Sporadic Fatal Insomnia (SFI) cases occur without PRNP mutation but with features similar to FFI. FFI represents a model disease for the study of sleep-wake regulation: (I) the profound thalamic hypometabolism/atrophy associated with lack of sleep spindles and delta sleep implicate the thalamus in the origin of slow wave sleep (SWS); (II) loss of SWS is associated with marked autonomic and motor hyperactivity; termed 'agrypnia excitata', this association has been proposed as a useful clinical concept representative of thalamo-limbic dysfunction; (III) lack of SWS occurs with substantial preservation of stage 1 NREM sleep, implying that the latter has mechanisms different from SWS and unaffected by thalamic atrophy; accordingly, conflating stage 1 NREM with SWS into NREM sleep is inappropriate. ( info) |