Neuropathologic characteristics of brainstem lesions in sporadic Creutzfeldt-Jakob disease

Creutzfeldt-Jakob disease presenting with bilateral hearing loss: A case report

BACKGROUND

Sporadic Creutzfeldt-Jakob disease (sCJD) is a prion disease characterized as a fatal transmissible neurodegenerative disorder. Dizziness is often the first presenting symptom of sCJD, but hearing loss as an early manifestation is very rare.

CASE SUMMARY

A 76-year-old man presented with bilateral sudden hearing impairment and dizziness for 10 d. He was taking medications for hypertension and diabetes. He denied any difficulty with activities of daily living or hearing impairment before the onset of symptoms. Pure tone audiometry showed bilateral severe hearing impairment. Brain magnetic resonance imaging (MRI) and laboratory tests were within normal limits. Given his diagnosis of sudden sensory hearing loss, the patient received corticosteroid treatment but it was ineffective. Two weeks later, he complained of aggravated gait impairment, disorientation, and cognitive impairment. Repeat brain MRI showed diffuse cortical high signal intensities on diffusion-weighted imaging. In cerebrospinal fluid analysis, the real-time quaking-induced conversion assay was positive, and 14-3-3 protein was detected in the by western blotting. Considering all the data, we diagnosed probable sCJD, and the patient’s symptoms rapidly progressed into akinetic mutism.

CONCLUSION

For patients with abrupt bilateral hearing impairment, especially in the elderly, various differential diagnoses, including sCJD, should be considered.

An autopsy case of MV2K-type sporadic Creutzfeldt-Jakob disease presenting with characteristic clinical, radiological, and neuropathological findings

In Japan, because MV2-type sporadic Creutzfeldt-Jakob disease (CJD) is rare, little is known about its clinical and neuropathological characteristics. An autopsy case of MV2K-type sporadic CJD is presented, and the characteristic clinical, radiological, and neuropathological findings are discussed. The patient was a Japanese woman who died at the age of 72 years. Her initial symptom was rapidly progressive dementia. She then developed truncal ataxia and delusions. Approximately nine months after onset, she exhibited akinetic mutism. The total clinical course was 11 months. Magnetic resonance imaging revealed hyperintensity areas in the basal ganglia, thalamus, and hippocampus on diffusion-weighted images. In the cerebral cortex, this finding was slight and inconspicuous. Electroencephalography revealed no periodic sharp wave complexes. Prion protein (PrP) gene analysis revealed no mutations, and polymorphic codon 129 exhibited methionine and valine heterozygosity. In the cerebrospinal fluid, levels of both total tau and 14-3-3 proteins were elevated. Grossly, the brain weighed 1050 g before fixation and exhibited diffuse cortical atrophy. On histopathological examination, extensive fine vacuole-type spongiform degeneration was noted in the cerebral cortex. Numerous kuru plaques were observed in the cerebellum. PrP immunohistochemistry revealed extensive diffuse synaptic- and perineuronal-type PrP deposits in the cerebral cortex. Kuru plaques were strongly immunoreactive for PrP. Western blot analysis of brain tissue samples revealed mixed type 2 and intermediate type. Systematic and comprehensive investigations of both clinical and neuropathological aspects are required for accurate diagnosis.

System degeneration in an MM1-type sporadic Creutzfeldt-Jakob disease case with an unusually prolonged akinetic mutism state

Methionine/methionine type 1 (MM1-type) sporadic Creutzfeldt-Jakob disease (sCJD), known as the ‘classic type,’ shows typical clinicopathological sCJD findings. In general, patients reach an akinetic mutism state within a few months of disease onset and die soon after if supportive therapies are not administered. Here, we describe remarkable neuropathologic observations of MM1-type sCJD in a 48-year-old, Japanese man with an unusually prolonged akinetic mutism state. In the early disease stages, the patient exhibited abnormal behaviour with gait disturbance and rapidly progressive cognitive dysfunction. Diffusion-weighted magnetic resonance imaging revealed extensive cerebral cortical hyperintensity. Prion protein (PrP) gene analysis revealed no mutations, and the polymorphic codon 129 exhibited methionine homozygosity. Although the patient remained stable with tube feeding for more than 2 years after reaching the akinetic mutism state, he died because of central respiratory failure 30 months after disease onset. Neuropathologic investigation showed extensive devastating lesions, such as status spongiosus, and typical spongiform changes could no longer be observed in the cerebral neocortex. Conspicuous pyramidal tract degeneration was observed. However, the regions commonly preserved in MM1-type sCJD pathology were still relatively preserved. Immunostaining revealed extensive diffuse synaptic-type PrP deposition in the grey matter. The pathological findings suggested that sCJD is a neurodegenerative disease that shows system degeneration; there are primary and secondary degenerative regions and distinct preserved regions, even in cases with prolonged disease duration. In addition, it is considered that there is a limited survival period for MM1-type sCJD, even if active symptomatic treatment is provided.

Pontine Neoplasm or Myelinolysis Despite Normal Sodium Levels

An elderly woman was transferred for biopsy of a pontine lesion. Her condition, including gait disturbances, truncal ataxia, and dysarthria-presumed to be due to severe alcohol abuse-had deteriorated during treatment of ambulatory-acquired pneumonia. No electrolyte abnormalities were noted during hospitalization. However, the neuroimaging findings were in line with central pontine myelinolysis, typically sparing the peripheral pontine fibers. Although extremely rare, pontine myelinolysis can occur in the presence of normal electrolyte levels. Thus, imaging findings should not be misinterpreted as pontine neoplasms, and patients should not undergo stereotactic biopsy-a procedure that could result in disastrous morbidity.

The Braak hypothesis in prion disease with a focus on Creutzfeldt-Jakob disease

This review considers whether the Braak hypothesis on protein propagation could account for prion disease, particularly Creutzfeldt-Jakob disease (CJD). In CJD, we can speculate on the pathological onset region to some degree in reference to the clinical symptoms and magnetic resonance imaging findings. Although relating the Braak hypothesis to prion disease is not straightforward, the following could be proposed based on experimental and previously reported case observations. Pathogenic abnormal prion protein (PrP) deposition in the central nervous system (CNS) probably begins several months or years before clinical symptom onset, signifying the potentiality of a preclinical stage, similar to α-synuclein deposition in Parkinson's disease (PD) and amyloid-β/tau deposition in Alzheimer's disease (AD). Unlike in PD and AD, the initial clinical symptoms of CJD vary by case, and thus the onset lesions must also be various and multiple in the CNS. Based on the pathological findings, particularly of PrP deposition extensively observed in the CNS gray matter of autopsy cases, it could be speculated that in the early disease stage, including the preclinical stage, abnormal PrP spreads from the onset region without directionality or hierarchy. Because each CNS region shows either vulnerability to or resistance against PrP deposition and pathological progression in prion disease, the lesion distribution shows system degeneration. Although pathologically combined cases of type 1 and type 2 PrP patterns are often recognized, type 1 and type 2 PrP patterns must never shift toward each other during the disease course; in other words, the original type of PrP deposition in each region presumably remains unchanged in each case. According to the several observations and corresponding speculations, there are at least partial similarities between prion disease and protein propagation, as explained by the Braak hypothesis, in terms of pathological lesion progression, but several noted contradictions preclude the hypothesis from comprehensively accounting for prion disease.

Correlating diffusion-weighted MRI intensity with type 2 pathology in mixed MM-type sporadic Creutzfeldt-Jakob disease

The existence of affected subjects with both abnormal prion protein (PrP^Sc) types has been reported, and their clinical features were somewhat similar to the dominant PrP^Sc type but varied in sporadic Creutzfeldt-Jakob disease (sCJD). Presently, the antemortem identification of both PrP^Sc types in sCJD is not possible. In this study, we attempted to clinically predict the concurrence of MM-type sCJD with another PrP^Sc type in the same individual. We retrospectively identified seven MM-type sCJD cases with both fine vacuole-type spongiform (FV) and large confluent vacuole-type spongiform change (LCV) among 49 sCJD cases. We reviewed clinical features, pathological findings, and radiological abnormalities in these seven cases. We also conducted a regional systemic study with five brains to associate the spongiform-change pattern with hyperintensity on magnetic resonance diffusion-weighted imaging (DWI) using the signal intensity index (SII). In the case series study, the one patient with dominant LCV showed longer disease duration, later onset of typical symptoms, no periodic sharp wave complexes in electroencephalography, and negative 14-3-3 protein findings compared to the six FV-dominant patients. LCV-dominant lesions tended to show higher intensity on DWI than did the FV-dominant lesions in respective patients. In the regional systemic study, LCV-dominant regions showed significantly higher SII on DWI than did the FV-dominant regions. In conclusion, mixed MM-type sCJD generally showed the clinical features of the phenotype that was dominant in pathological distribution. The SII may be clinically useful for investigating the concurrence of PrP^Sc type 2 in cases with the typical clinical course of MM1-type sCJD.

Accumulation of prion protein in the vagus nerve in creutzfeldt-jakob disease

Disease‐associated proteins are thought to propagate along neuronal processes in neurodegenerative diseases. To detect disease‐associated prion protein (PrP^Sc) in the vagus nerve in different forms and molecular subtypes of Creutzfeldt–Jakob disease (CJD), we applied 3 different anti‐PrP antibodies. We screened the vagus nerve in 162 sporadic and 30 genetic CJD cases. Four of 31 VV‐2 type sporadic CJD and 7 of 30 genetic CJD cases showed vagal PrP^Sc immunodeposits with distinct morphology. Thus, PrP^Sc in CJD affects the vagus nerve analogously to α‐synuclein in Parkinson disease. The morphologically diverse deposition of PrP^Sc in genetic and sporadic CJD argues against uniform mechanisms of propagation of PrP^Sc. Ann Neurol 2019;85:782–787

[A case of Creutzfeldt-Jakob disease with E200K mutation presenting with hearing loss and central hypoventilation]

We report the case of a 43-year-old female patient who presented with symptoms of abnormal behavior, hearing loss, ataxic gait, central hyperventilation which had appeared over the course of one month. Brain MRI showed no abnormal findings in DWI and EEG did not indicate periodic synchronous discharge (PSD). Over the course of the same month, she also presented with central apnea that intermittently showed spontaneous improvement and reappearance. Cerebrospinal fluid 14-3-3 protein tested negative and there was no family history, but an abnormal prion protein was detected in the cerebrospinal fluid by the RT-QUIC assay. We diagnosed her with familial Creutzfeldt-Jakob disease (CJD) with an E200K mutation after genetic examination. Both high cortical signals on MRI and PSD on EEG were not recognized even in the advanced stage. Central apnea was presumed to be caused by disorders of the respiratory center of the brainstem. Hearing loss was also considered to be an obstacle at the brainstem level from the latency delay after the III wave in auditory brainstem response (ABR). The possibility of brain stem symptoms occurring in the early stages of CJD should be considered.

An autopsied case of MM1-type sporadic Creutzfeldt-Jakob disease with pathology of Wernicke encephalopathy

An 83-year-old Japanese man presented with gait disturbance followed by rapidly-progressive cognitive impairment. Magnetic resonance diffusion-weighted images showed extensive hyperintense regions in the cerebral cortex. Four weeks after symptom onset, myoclonus appeared, and the patient developed difficulty swallowing; intravenous peripheral continuous infusions without vitamin supplementation were administered during the last two months of the patient’s life. The patient reached the akinetic mutism state and died 12 weeks after symptom onset due to sepsis. The brain weighed 940 g and showed general cerebral atrophy. Extensive spongiform change were observed in the cerebral cortex, striatum, thalamus, and cerebellar cortex, but gliosis was generally mild. Numerous newly-developed hemorrhage foci were observed in the mammillary body, the areas adjacent to the third and fourth ventricles, and the periaqueduct of the midbrain; however, proliferation of capillaries and endothelium and collections of macrophages were relatively inconspicuous. These findings suggested comorbidity with the acute stage of Wernicke encephalopathy (WE). Immunostaining showed extensive diffuse synaptic-type prion protein deposition in the gray matter. According to the neuropathological, genetic, and molecular findings, the present case was finally diagnosed as MM1-type sporadic Creutzfeldt-Jakob disease (CJD) with WE. We should remain alert to the diagnosis of WE when CJD is suspected, and it is necessary to consider the complications of both diseases. This report emphasizes the importance of pathological investigations for the diagnosis of CJD, WE, and the coexistence of both.

Pathological progression of genetic Creutzfeldt-Jakob disease with a PrP V180I mutation

In comparison to sporadic Creutzfeldt-Jakob disease (sCJD) with MM1-type and MM2- cortical (MM2C)-type, genetic CJD with a prion protein gene V180I mutation (V180I gCJD) is clinically characterized by onset at an older age, slower progress, and the absence of visual disturbances or cerebellar symptoms. In terms of pathological characteristics, gliosis and neuronal loss are generally milder in degree, and characteristic spongiform change can be observed at both the early and advanced stages. However, little is known on the progress of spongiform change over time or its mechanisms. In this study, to elucidate the pathological course of V180I gCJD, statistical analysis of the size and dispersion of the major diameters of vacuoles in six V180I gCJD cases was performed, with five MM1-type sCJD and MM2C-type sCJD cases as controls. As a result, V180I gCJD showed no significant difference in vacuolar diameter regardless of disease duration. In addition, the dispersion of the major diameters of vacuoles in V180I gCJD was larger than that in the MM1-type, which was smaller than that in the MM2C-type. We speculated that the absence of difference in the size of the vacuoles regardless of disease duration suggests that tissue rarefaction does not result from the expansion of vacuole size and increase in number of vacuoles in V180Ig CJD. These features were considered to be significant pathological findings of V180I gCJD.

An autopsy-verified case of steroid-responsive encephalopathy with convulsion and a false-positive result from the real-time quaking-induced conversion assay

We report an autopsy-verified case of steroid-responsive encephalopathy with convulsion and a false-positive result from the real-time quaking-induced conversion (RT-QUIC) assay. A 61-year-old Japanese man presented with acute onset of consciousness disturbance, and convulsions, but without a past medical or family history of progressive dementia, epilepsy, or prion disease. Brain diffusion and fluid-attenuated inverted recovery MR images revealed edematous cortical hyper-intensity, which diminished after the acute phase. Steroid pulse therapy was partially effective, although he continued to have dementia with myoclonus and psychiatric symptoms, despite resolution of the consciousness disturbance. Cerebrospinal fluid (CSF) analysis revealed a normal cell count, with significantly elevated levels of 14-3-3 protein and total tau protein. In addition, prion protein in the CSF was slowly amplified by the RT-QUIC assay. PRNP gene analysis revealed methionine homozygosity at codon 129 without mutation. The patient died of sudden cardiac arrest at 3 months after the onset of symptoms. The positive result from the RT-QUIC assay led us to suspect involvement of prion disease, although a postmortem assessment revealed that he had pathological changes after convulsion, and no prion disease. This case indicates that convulsion may cause false-positive RT-QUIC results, and that a postmortem evaluation remains the gold standard for diagnosing similar cases.

MM1-type sporadic Creutzfeldt-Jakob disease with 1-month total disease duration and early pathologic indicators

A 62-year-old man presented with abnormal behavior and cognitive impairment. Diffusion-weighted images (DWI) obtained on MRI showed extensive hyperintense regions in the cerebral cortex and striatum. Myoclonus was recognized, and the patient died 1 month after the onset; his condition did not reach the akinetic mutism state. The brain weighed 1300 g and showed no apparent atrophy. Extensive spongiform changes were observed in the cerebral neocortex, striatum, thalamus and cerebellar cortex, but gliosis was mild or absent. Neuropil rarefaction and neuron loss were not apparent. Mild proliferation of anti- GFAP-positive astrocytes was observed in the cerebral cortex, but unaffected regions were noted. Regions without spongiform changes and GFAP-positive astrocytes included the hippocampal formation and subiculum. PrP immunostaining showed extensive diffuse synaptic-type PrP deposition in the gray matter, including the hippocampal region, but it was also mild. PrP gene analysis revealed no mutation with methionine homozygosity at polymorphic codon 129. Western blot analysis of proteinase K-resistant PrP indicated type 1 PrP^Sc . The clinicopathological findings of the present case confirm several hypotheses: (i) the earliest pathologic evidence observed by HE staining in CJD are spongiform changes; (ii) DWI hyperintense regions indicate these spongiform changes; and (iii) regions without spongiform changes, gliosis and proliferation of GFAP-positive astrocytes, but with PrP deposition, exist in the early disease stage.

Creutzfeldt-Jakob disease

This review will explore the clinical and pathological findings of the various forms of Creutzfeldt-Jakob disease (CJD). Clinical findings of CJD are characterized by rapidly progressive cognitive dysfunction, diffusion-weighted magnetic resonance imaging (DWI) hyperintensity, myoclonus, periodic sharp-wave complexes on electroencephalogram and akinetic mutism state. Neuropathologic findings of CJD are characterized by spongiform changes in gray matter, gliosis-particularly hypertrophic astrocytosis-neuropil rarefaction, neuron loss and prion protein (PrP) deposition. The earliest pathological symptom observed by HE staining in the cerebral cortex is spongiform change. This spongiform change begins several months before clinical onset, and is followed by gliosis. Subsequently, neuropil rarefaction appears, followed by neuron loss. Regions showing fine vacuole-type spongiform change reflect synaptic-type PrP deposition and type 1 PrP^Sc deposition, whereas regions showing large confluent vacuole-type spongiform changes reflect perivacuolar-type PrP deposition and type 2 PrP^Sc deposition. Hyperintensities of the cerebral gray matter observed in DWI indicate the pathology of the spongiform change in CJD. The cerebral cortical lesions with large confluent vacuoles and type 2 PrP^Sc show higher brightness and more continuous hyperintensity on DWI than those with fine vacuoles and type 1 PrP^Sc . CJD cases showing diffuse myelin pallor of cerebral white matter have been described as panencephalopathic-type, and this white matter pathology is mainly due to secondary degeneration caused by cerebral cortical involvement, particularly in regard to neuron loss. In conclusion, clinical and neuroimaging findings and neuropathologic observations are well matched in both typical and atypical cases in CJD. The clinical diagnosis of CJD is relatively easy for typical CJD cases such as the MM1-type. However, even in atypical cases it seems that clinical findings can be used for an accurate diagnosis.

An autopsy-verified case of FTLD-TDP type A with upper motor neuron-predominant motor neuron disease mimicking MM2-thalamic-type sporadic Creutzfeldt-Jakob disease

Here we report an autopsy-verified case of frontotemporal lobar degeneration (FTLD)-transactivation responsive region (TAR) DNA binding protein (TDP) type A with upper motor neuron-predominant motor neuron disease mimicking MM2-thalamic-type sporadic Creutzfeldt-Jakob disease (sCJD). A 69-year-old woman presented with an 11-month history of progressive dementia, irritability, insomnia, and gait disturbance without a family history of dementia or prion disease. Neurological examination revealed severe dementia, frontal signs, and exaggerated bilateral tendon reflexes. Periodic sharp-wave complexes were not observed on the electroencephalogram. Brain diffusion MRI did not reveal abnormal changes. An easy Z score (eZIS) analysis for ^99mTc-ECD-single photon emission computed tomography (^99mTc-ECD-SPECT) revealed a bilateral decrease in thalamic regional cerebral blood flow (rCBF). PRNP gene analysis demonstrated methionine homozygosity at codon 129 without mutation. Cerebrospinal fluid (CSF) analysis showed normal levels of both 14-3-3 and total tau proteins. Conversely, prion protein was slowly amplified in the CSF by a real-time quaking-induced conversion assay. Her symptoms deteriorated to a state of akinetic mutism, and she died of sudden cardiac arrest, one year after symptom onset.  Despite the SPECT results supporting a clinical diagnosis of MM2-thalamic-type sCJD, a postmortem assessment revealed that this was a case of FTLD-TDP type A, and excluded prion disease. Thus, this case indicates that whereas a bilateral decreasing thalamic rCBF detected by ^99mTc-ECD-SPECT can be useful for diagnosing MM2-thalamic-type sCJD, it is not sufficiently specific. Postmortem diagnosis remains the gold standard for the diagnosis of this condition.

Sporadic Creutzfeldt-Jakob Disease: Prion Pathology in Medulla Oblongata-Possible Routes of Infection and Host Susceptibility

Sporadic Creutzfeldt-Jakob disease (sCJD), the most frequent human prion disorder, is characterized by remarkable phenotypic variability, which is influenced by the conformation of the pathologic prion protein and the methionine/valine polymorphic codon 129 of the prion protein gene. While the etiology of sCJD remains unknown, it has been hypothesized that environmental exposure to prions might occur through conjunctival/mucosal contact, oral ingestion, inhalation, or simultaneous involvement of the olfactory and enteric systems. We studied 21 subjects with definite sCJD to assess neuropathological involvement of the dorsal motor nucleus of the vagus and other medullary nuclei and to evaluate possible associations with codon 129 genotype and prion protein conformation. The present data show that prion protein deposition was detected in medullary nuclei of distinct sCJD subtypes, either valine homozygous or heterozygous at codon 129. These findings suggest that an "environmental exposure" might occur, supporting the hypothesis that external sources of contamination could contribute to sCJD in susceptible hosts. Furthermore, these novel data could shed the light on possible causes of sCJD through a "triple match" hypothesis that identify environmental exposure, host genotype, and direct exposure of specific anatomical regions as possible pathogenetic factors.

Identification of clinical target areas in the brainstem of prion-infected mice

AIMS

While prion infection ultimately involves the entire brain, it has long been thought that the abrupt clinical onset and rapid neurological decline in laboratory rodents relates to involvement of specific critical neuroanatomical target areas. The severity and type of clinical signs, together with the rapid progression, suggest the brainstem as a candidate location for such critical areas. In this study we aimed to correlate prion pathology with clinical phenotype in order to identify clinical target areas.

METHOD

We conducted a comprehensive survey of brainstem pathology in mice infected with two distinct prion strains, which produce different patterns of pathology, in mice overexpressing prion protein (with accelerated clinical onset) and in mice in which neuronal expression was reduced by gene targeting (which greatly delays clinical onset).

RESULTS

We identified specific brainstem areas that are affected by prion pathology during the progression of the disease. In the early phase of disease the locus coeruleus, the nucleus of the solitary tract, and the pre-Bötzinger complex were affected by prion protein deposition. This was followed by involvement of the motor and autonomic centres of the brainstem.

CONCLUSIONS

Neurodegeneration in the locus coeruleus, the nucleus of the solitary tract and the pre-Bötzinger complex predominated and corresponded to the manifestation of the clinical phenotype. Because of their fundamental role in controlling autonomic function and the overlap with clinical signs in sporadic Creutzfeldt-Jakob disease, we suggest that these nuclei represent key clinical target areas in prion diseases.

At the centre of neuronal, synaptic and axonal pathology in murine prion disease: degeneration of neuroanatomically linked thalamic and brainstem nuclei

Aims

The processes by which neurons degenerate in chronic neurodegenerative diseases remain unclear. Synaptic loss and axonal pathology frequently precede neuronal loss and protein aggregation demonstrably spreads along neuroanatomical pathways in many neurodegenerative diseases. The spread of neuronal pathology is less studied.

Methods

We previously demonstrated severe neurodegeneration in the posterior thalamus of multiple prion disease strains. Here we used the ME7 model of prion disease to examine the nature of this degeneration in the posterior thalamus and the major brainstem projections into this region.

Results

We objectively quantified neurological decline between 16 and 18 weeks post‐inoculation and observed thalamic subregion‐selective neuronal, synaptic and axonal pathology while demonstrating relatively uniform protease‐resistant prion protein (PrP) aggregation and microgliosis across the posterior thalamus. Novel amyloid precursor protein (APP) pathology was particularly prominent in the thalamic posterior (PO) and ventroposterior lateral (VPL) nuclei. The brainstem nuclei forming the major projections to these thalamic nuclei were examined. Massive neuronal loss in the PO was not matched by significant neuronal loss in the interpolaris (Sp5I), while massive synaptic loss in the ventral posteromedial nucleus (VPM) did correspond with significant neuronal loss in the principal trigeminal nucleus. Likewise, significant VPL synaptic loss was matched by significant neuronal loss in the gracile and cuneate nuclei.

Conclusion

These findings demonstrate significant spread of neuronal pathology from the thalamus to the brainstem in prion disease. The divergent neuropathological features in adjacent neuronal populations demonstrates that there are discrete pathways to neurodegeneration in different neuronal populations.

Bilateral hearing loss heralding sporadic Creutzfeldt-Jakob disease: a case report and literature review

OBJECTIVE

To report a case of sporadic Creutzfeldt-Jakob disease (CJD) with bilateral hearing loss at onset and literature review of the scarce cases of CJD with similar audiologic manifestations at presentation.

CASE REPORT

A 67-yr-old man presented to the hospital for evaluation of rapid progression of behavioral decline, unsteady gait, and bilateral hearing loss. Three months before admission, he abruptly developed bilateral hypoacusis without associated tinnitus or vertigo. Shortly after, his family noted an ataxic gait and behavioral changes, for example, paranoid delusions. Initial workup, including a complete autoimmune panel and heavy metals, infectious, toxicology, and paraneoplastic panel (e.g., anti-Hu, anti-VGKC), was conducted. Electroencephalography revealed diffuse generalized slowing without periodic complexes. The presence of distortion product otoacoustic emissions bilaterally was consistent with normal cochlear function, suggesting a retrocochlear origin for symptoms of hearing loss. In the meantime, the patient developed startle myoclonus. The brain magnetic resonance imaging demonstrated asymmetric cortical ribbon along with T2 FLAIR signal hyperintensities of bilateral basal ganglia. Later on, the protein 14-3-3 in the cerebrospinal fluid came back positive, which supported the diagnosis of CJD. Only three cases of CJD with deafness at onset have been published: one sporadic, associated with symptoms suggestive of polyneuropathy; and the other two familial, with the E200K mutation. One presented with symptoms of polyneuropathy and the other with typical features.

CONCLUSION

This case illustrates the phenotypic variability of presentation of CJD in a patient with hearing loss as the initial manifestation. In patients with subacute bilateral hypoacusis and signs of dementia, the differential diagnosis of CJD must be taken into consideration.

Comparison of the clinical course of Japanese MM1-type sporadic Creutzfeldt-Jakob disease between subacute spongiform encephalopathy and panencephalopathic-type

BACKGROUND

Approximately half of Japanese sporadic Creutzfeldt-Jakob disease (sCJD) cases show panencephalopathic-type (PE-type) pathology, which is a rare subtype in North Americans and Europeans. Until now, the differences in the clinical course between subacute spongiform encephalopathy (SSE) cases and PE-type cases have been unclear.

METHODS

To investigate the clinical course of both subtypes, clinical findings from 42 Japanese MM1-type sCJD cases (20 SSE cases and 22 PE-type cases) were retrospectively evaluated by statistical analysis.

RESULTS

No significant differences could be found regarding age at disease onset, the period between disease onset and first observation of myoclonus, the period between disease onset and the first observation of periodic sharp-wave complexes on electroencephalogram, or the period between disease onset and progression to the akinetic mutism state - whereas total disease duration and the period between the akinetic mutism state and death were significantly longer in PE-type cases. The prolonged disease duration was induced by the extended survival period in the akinetic mutism state. There was a statistically significant difference between the two series regarding performance of tube-feeding, but no statistically significant difference regarding performance of tracheotomy or gastrostomy. None of the cases received mechanical ventilation.

CONCLUSION

We speculate that the most crucial factor of the prolonged survival period of Japanese sCJD cases, particularly in the PE-type, is that the introduction of tube-feeding in the akinetic mutism state leads to the stabilization of the patient's general condition.

Relation between clinical findings and progression of cerebral cortical pathology in MM1-type sporadic Creutzfeldt-Jakob disease: proposed staging of cerebral cortical pathology

In our pathologic observation of the cerebral cortex including the neocortex, hippocampus, and limbic cortex in 43 Japanese patients with MM1-type sporadic Creutzfeldt-Jakob disease, the earliest pathologic finding was spongiform change and next was gliosis. Subsequently, neuropil rarefaction appeared, followed by neuron loss. On the basis of these observations, we propose the following cortical pathologic staging: Stage I, spongiform change; Stage II, hypertrophic astrocytosis; Stage III, neuropil rarefaction; Stage IV, neuron loss; Stage V, status spongiosus; and Stage VI, large cavity formation. We also suggest a more simple staging classification: Stages I and II, mild; Stages III and IV, moderate; and Stages V and VI, severe involvement. Based on statistical analysis of the cases, strong correlation coefficients were obtained between the neocortical and limbic pathologic stage and both total disease duration and brain weight. We estimated that the first observation times of cortical hyperintensity on diffusion-weighted images of magnetic resonance imaging, myoclonus, and periodic sharp wave complexes on the electroencephalogram approximately correspond to the early phase of Stage II of the neocortex. The time to reach the akinetic mutism state approximately corresponds to the middle phase of Stage II of the neocortex. Therefore, we think that approximate clinical manifestations at death, total disease duration, and brain weight can be estimated according to the pathologic stage of the neocortex or limbic cortex. Panencephalopathic-type pathology appeared approximately 12 months after disease onset, and this time approximately corresponds to the middle phase of Stage III of the neocortex.

Increased interleukin-17 in the cerebrospinal fluid in sporadic Creutzfeldt-Jakob disease: a case-control study of rapidly progressive dementia

BACKGROUND

Inflammatory responses in the cerebrospinal fluid (CSF) of patients with sporadic Creutzfeldt-Jakob disease (sCJD) remain elusive.

METHODS

We conducted a case-control study, in which 14 patients with sCJD, 14 with noninflammatory neurological disorders, and 14 with autoimmune encephalitis were enrolled. We used the suspension array system to measure the concentrations of 27 cytokines in CSF. The cytokine titers of the three groups were compared, and the correlation between the relevant cytokine titers and clinical parameters was investigated in the patients with sCJD.

RESULTS

Levels of the two cytokines interleukin (IL)-1 receptor antagonist and IL-17 were significantly elevated in the patients with sCJD compared with those in the patients with noninflammatory neurological disorders: IL-17 levels in sCJD were approximately ten times higher than in the noninflammatory neurological disorders (mean, 35.46 vs. 3.45 pg/ml; P < 0.001) but comparable to that in encephalitis (mean, 32.16 pg/ml). In contrast, levels of classical proinflammatory cytokines such as IL-12(p70) and tumor necrosis factor-α were increased only in encephalitis. Although not significant, IL-17 titers tended to be higher in the patients with shorter disease duration before CSF sampling (r = -0.452; P = 0.104) and in those with lower CSF total protein concentrations (r = -0.473; P = 0.086).

CONCLUSIONS

IL-17 is significantly increased in CSF in sCJD, which can be an early event in the pathogenesis of sCJD.

An autopsied case of Creutzfeldt-Jakob disease with mutation in the prion protein gene codon 232 and type 1+2 prion protein

A 68-year-old Japanese man gradually showed abnormal behavior and gait disturbance with bradykinesia. Slowly progressive dementia, including memory disturbance and disorientation, was also observed. Cerebral cortical hyperintensity on diffusion-weighted MRI was observed 6 months after onset. The patient progressed to an akinetic mutism state with mild myoclonus, and atypical periodic sharp-wave complexes were observed by electroencephalogram 13 months after onset. He was clinically suspected of having atypical CJD and died after 19 months total disease duration. The brain weighed 1160 g and showed mild atrophy of the cerebrum and cerebellum with ventricular dilatation. Spongiform changes with varying vacuole size and gliosis was extensive in the cerebral cortex and basal ganglia. Neuron loss in the cerebral cortex, basal ganglia and thalamus was relatively mild. The cerebellum showed mild spongiform changes of the molecular layer and mild neuron loss in the Purkinje cell layer. PrP immunostaining showed mainly coarse-type combined with diffuse synaptic-type PrP deposition in the cerebral gray matter. Some perivacuolar-type PrP deposition was also present. Numerous plaque-type PrP depositions were observed in the molecular layer of the cerebellum. Analysis of the PrP gene revealed a methionine-to-arginine (Met-to-Arg) substitution at codon 232 (M232R) with Met homozygosity at codon 129. Western blot analysis of protease-resistant PrP indicated type 2 dominant PrP combined with type 1. Genetic CJD with M232R substitution in the PrP gene has only been reported in Japan. Although two clinical phenotypes (rapid-type and slow-type) were suggested in the M232R CJD cases (despite the presence of the same PrP genotype), the pathological and molecular backgrounds have not been well understood because there have only been a few autopsied case reports. This is the first case report of M232R CJD presenting with 1 + 2 PrP.

[Cheyne-Stokes respiration appeared in an early stage of the disease in a patient with Creutzfeldt-Jakob disease]

A 77-year-old female developed vertigo and dysarthria. Two months later, she was hospitalized with disorientation and ataxia. CSF showed increased levels of NSE, 14-3-3 protein and tau. EEG demonstrated periodic synchronous discharges (PSD). Brain MRI showed abnormal high intensity areas in the cerebral cortices, especially in the occipital lobes, putamen and caudate nucleus bilaterally, on DWI. Genetical analysis of prion protein revealed no specific mutation. She was diagnosed as having sporadic Creutzfeldt-Jakob disease (CJD). Cheyne-Stokes respiration (CSR) had been observed since an early stage, and decreased 5 months later coincident with attenuation of myoclonus and PSD. We should also pay attention to CSR in the diagnosis of CJD, although the complication is rare.

[Investigation of the clinical course and treatment of prion disease patients in the akinetic mutism state in Japan]

Twelve cases (one Gerstmann-Sträussler-Scheinker syndrome (P102L; definite), one genetic Creutzfeldt-Jakob disease (CJD) (V180I; definite) and ten sporadic CJD (7 MM1-type definite, 3 probable)), who reached the akinetic mutism state, were investigated with regard to their clinical course and treatment. They were hospitalized for a total of 3,968 days in the akinetic mutism state. In the nine definite cases, the median period from the akinetic mutism state to death was 22 months (average: 27.0 ± 23.3 months, range: 3-80 months) and median total disease duration was 27 months (average: 34.2 ± 30.1 months, range: 5-102 months). In the seven definite sporadic CJD cases, the median period from akinetic mutism to death was 21 months (average: 17.0 ± 9.6 months, range 3-28 months), and median total disease duration was 24 months (average: 20.6 ± 10.0 months, range: 5-31 months). Nasal-tube feeding was performed in all cases. Symptomatic treatments such as parenteral nutrition and antibiotic drugs were administered for complications such as respitory and urinary tract infections and digestive symptoms. Patients received rehabilitation and hot spring therapy regularly until death. Gastrostomy and/or tracheotomy was not performed in any case, the patients were not intubated nor was mechanical ventilation (including non-invasive positive pressure ventilation) applied. Vasoactive drugs were not administered. Clonazepam was administered for myoclonus in four patients but not in another three when myoclonus appeared. It is unclear whether the treatment influenced the duration of myoclonus. Our observations indicate that the extended survival period among Japanese prion disease patients is likely due to the management procedures implemented for prion disease in Japan, which are usually continued after the patients reach the akinetic mutism state. We speculate that nasal-tube feeding is the crucial factor that results in the prolonged disease duration of prion disease patients in the akinetic mutism state.

Survival to akinetic mutism state in Japanese cases of MM1-type sporadic Creutzfeldt-Jakob disease is similar to Caucasians

BACKGROUND

It is not known whether the clinical course of Japanese sporadic Creutzfeldt-Jakob disease (sCJD) cases differs from that of Caucasian sCJD cases.

PATIENTS AND METHODS

To investigate the clinical course of Japanese sCJD, clinical findings from 29 patients with Japanese MM1-type sCJD were retrospectively evaluated and compared to Caucasian sCJD findings.

RESULTS

Survival of Japanese MM1-type sCJD up to the time of akinetic mutism state is similar to that of Caucasian subjects. However, the total disease duration of Japanese patients was approximately three times longer.

CONCLUSIONS

The present observations indicate that Japanese sCJD cases generally show a longer disease duration because of the longer survival period after reaching the akinetic mutism state.

An autopsied case of panencephalopathic-type Creutzfeldt-Jakob disease with mutation in the prion protein gene at codon 232 and type 1 prion protein

In this study, we describe the clinicopathologic findings in a 68-year-old man with panencephalopathic-type CJD with a substitution from methionine to arginine at codon 232 (M232R) in the prion protein (PrP) gene and type 1 PrP. Initial symptoms of the patient were a rapidly progressive memory disturbance and disorientation. The patient showed myoclonus and periodic sharp-wave complexes on electroencephalogram in the early stages of disease. Diffusion-weighted MRI along with the presence of both neuron-specific enolase and 14-3-3 protein in the CSF showed similarities to classic-type sporadic CJD. The patient reached the akinetic mutism state 2 months following the onset of symptoms and died after 13 months. Neuropathologic examination revealed panencephalopathic-type CJD pathology including widespread neuron loss with severe hypertrophic astrocytosis and status spongiosus in the cerebral gray matter, particularly in the neocortex. Cerebral white matter and the cerebellum also showed severe involvement. Immunohistochemical staining for PrP showed diffuse gray matter staining, indicating synaptic-type PrP deposition without plaque-type. Two different clinical phenotypes of M232R CJD were recognized despite the presence of the same PrP genotype, and the present case is speculated to correspond to the rapid-type.

Clinicopathologic characteristics of five autopsied cases of dura mater-associated Creutzfeldt-Jakob disease

We present five cases of dura mater-associated Creutzfeldt-Jakob disease (dura-CJD) that were analyzed clinicopathologically and review previous reports. The average age at dura mater transplantation was 54.4 +/- 7.3 years, and the average age at CJD onset was 66.0 +/- 8.2 years, with an average latency period of 11.6 +/- 1.1 years. The average age at death was 67.6 +/- 8.7 years, with an average CJD disease duration of 16.8 +/- 10.4 months. Symptoms of CJD onset in four patients who received dura mater transplantation below the cerebellar tent reflected cerebellar or brainstem dysfunction, whereas symptoms of one patient who received transplantation above the cerebellar tent reflected cerebral cortical involvement. All patients showed rapidly progressive cognitive impairment, and both periodic sharp-wave complexes on electroencephalogram and myoclonus were observed in the early disease stage. Neuropathologic evaluation showed one case of subacute spongiform encephalopathy and four cases of panencephalopathic-type CJD. Widespread cerebral neocortical, subcortical gray matter and cerebellar cortical involvement were observed to varying degrees, and severity tended to be associated with CJD disease duration. There were no instances of kuru plaques or florid plaques. Prion protein (PrP) immunostaining showed widespread synaptic-type PrP deposition. No differences between our dura-CJD cases and typical cases of sporadic CJD were found with respect to clinicopathologic findings, except history of dura mater transplantation. Although a specific association between the dura mater graft site and neuropathologic observations was not evaluated in the present study, the initial symptoms appear to be closely related to the graft site, indicating a direct transmission of CJD from the graft site to the adjacent brain.

MM2-cortical-type sporadic Creutzfeldt-Jakob disease with early stage cerebral cortical pathology presenting with a rapidly progressive clinical course

We report the case of a 67-year-old man with MM2-cortical-type sporadic Creutzfeldt-Jakob disease (sCJD) with a rapidly progressive clinical course of 5 months. Initial symptoms were progressive memory disturbance and dementia. MRI revealed high signal-intensity lesions on diffusion-weighted images in the bilateral frontal and occipital cortices. Myoclonus and periodic sharp-wave complexes on the electroencephalogram were observed in the early disease stage. The clinical diagnosis was typical sCJD. Neuropathologic examination at autopsy showed widespread, characteristic cerebral neocortical involvement with large confluent vacuole-type spongiform change. Spongiform degeneration was also evident in the striatum and medial thalamus. In the cerebellar cortex, slight depletion of Purkinje neurons was evident without spongiform change in the molecular layer or apparent neuron loss in the granule cell layer. The inferior olivary nucleus showed slight hypertrophic astrocytosis without neuron loss. Prion protein (PrP) immunostaining showed widespread, characteristic perivacuolar-type PrP deposits with irregular plaque-like PrP deposits in the cerebral neocortex, striatum and medial thalamus. We believe this patient showed early-stage cerebral cortical pathology of MM2-cortical-type sCJD, which may provide clues regarding the pathologic progression of this rare sCJD subtype. Although MM2-cortical-type sCJD generally shows slow progression without myoclonus or periodic sharp-wave complexes, the present patient showed a rapidly progressive clinical course similar to that of MM1-type sCJD.

MM1-type sporadic Creutzfeldt-Jakob disease with unusually prolonged disease duration presenting with panencephalopathic-type pathology

We report an autopsy case of MM1-type sporadic Creutzfeldt-Jakob disease (sCJD) with an unusually prolonged disease duration of 58 months. The initial symptom was progressive mental disorder followed by advanced cognitive impairment. Clinical progression was generally slow; myoclonus appeared at 17 months and periodic sharp-wave complexes on electroencephalogram at 21 months. A state of akinetic mutism occurred 29 months after the onset of symptoms. MRI showed gradually progressive cerebral atrophy. Neuropathologic examination showed widespread severe brain involvement. In the cerebral neocortex, widespread severe tissue rarefaction, hypertrophic astrocytosis and neuron loss (so-called status spongiosus) were observed. The cerebral white matter showed diffuse myelin pallor with intense hypertrophic astrocytosis, numerous foamy macrophages and emperipolesis, indicating panencephalopathic-type sCJD pathology. The brainstem was relatively preserved from sCJD pathology, with the exception of the pontine nucleus and pyramidal tract. This may explain the prolonged disease duration without respiratory insufficiency until the terminal stage. Immunohistochemistry for prion protein (PrP) showed widespread synaptic-type PrP deposits in the cerebral neocortex, hippocampus and thalamus. The striatum and cerebellar cortex showed faint synaptic-type PrP deposition with some areas of small plaque-like PrP deposition. Sparse PrP deposition was also observed in the brainstem. Analysis of the PrP gene showed no mutation but methionine homozygosity at polymorphic codon 129. Western blot analysis of protease-resistant PrP indicated type 1 PrP. To our knowledge, this is the longest reported disease duration of MM1-type sCJD.

Enhanced Aquaporin-4 immunoreactivity in sporadic Creutzfeldt-Jakob disease

Aquaporin-4 (AQP-4) is a water channel protein located on the plasma membrane of astrocytes and is regulated under various conditions. In the present study, a series of brains with sporadic Creutzfeldt-Jakob disease (sCJD) were investigated to determine the possible contribution of AQP-4 in the development of sCJD pathology. Six cases of subacute spongiform encephalopathy (SSE) and four cases of panencephalopathic (PE)-type sCJD were included. Increased AQP-4 immunoreactivity compared to that in controls was observed in all sCJD patients, particularly in the cerebral neocortex and cerebellar cortex. AQP-4 immunoreactivity was present in the cell bodies and processes of protoplasmic astrocytes in SSE and around cell bodies and processes of hypertrophic astrocytes in PE-type sCJD. Analysis of serial sections showed the development of sCJD pathology, particularly in neocortical lesions, as follows: PrP deposition; spongiform change and gliosis; enhanced staining for AQP-4; hypertrophic astrocytosis; and neuronal loss and tissue rarefaction. Strong AQP-4 immunoreactivity was present in burnt-out lesions such as those of status spongiosus. These results indicate that increased AQP-4 expression in sCJD is an early pathologic event and appears to remain until the late disease stage. We suggest that increased expression of AQP-4 is a pathologic feature of sCJD.

Autopsy case of sporadic Creutzfeldt-Jakob disease presenting with signs suggestive of brainstem and spinal cord involvement

We describe an autopsy case of MM1-type sporadic Creutzfeldt-Jakob disease (CJD), the duration of which was 93 days. The patient was a 59-year-old Japanese man with no family history of prion disease or known iatrogenic exposure to CJD. His first symptom was dysesthesia in the left arm, suggestive of cervical cord involvement, and he showed rapidly progressive neurologic signs, such as dysarthria, dysphagia, lethargy, sleep apnea and respiratory failure, suggestive of brainstem involvement. Progressive mental deterioration combined with episodes of myoclonic seizure and periodic synchronous discharges on the electroencephalogram were observed in the later disease stage. Autopsy showed typical spongiform change to be wide-spread in the cerebral and cerebellar cortices, thalamus and basal ganglia. Synaptic-type PrP deposition was marked in the cerebral cortex, thalamus and basal ganglia. In the cerebellum, although the granular, molecular and Purkinje cell layers were well preserved from neuronal loss and gliosis, PrP deposition was marked in the molecular and granular cell layers. Spongiform degeneration and neuronal loss were not seen in the brainstem and spinal cord, but relatively marked PrP deposition was observed in the quadrigeminal body, substantia nigra, pontine nucleus, inferior olivary nucleus and posterior horn. Immunohistochemical staining for HLA-DR showed proliferation of activated microglia in the cerebral and cerebellar cortices, pontine nucleus, inferior olivary nucleus and posterior horn. The mechanisms underlying the neurologic symptoms and signs were unclear, but we speculate that, in addition to widespread involvement of the cerebral cortex, PrP deposition and microglial activation in the brainstem and spinal cord were responsible.

Source localization of periodic sharp wave complexes using independent component analysis in sporadic Creutzfeldt-Jakob disease

Patients with Creutzfeldt-Jakob disease (CJD) show periodic sharp wave complexes (PSWCs) on electroencephalography (EEG) during the course of their illness. However, the source location of PSWCs and their pathophysiological mechanism remain unclear. Six patients with sporadic CJD who showed typical PSWCs on EEGs were selected for the study. Sixty epochs, each spanning the period from -0.25 to +0.25 s after the negative maximum of a typical PSWC, were selected for analysis in each patient. The EEG data matrix was decomposed using an independent component analysis based on a simple, neural network algorithm that can blindly separate mixtures of independent sources, using information maximization. The separate independent components were subjected to dipole source localization using a single dipole model. Three to seven independent components responsible for the PSWCs seen in CJD were identified. The EEG recording reconstructed from the selected independent components accounted for more than 80% of the variance in the original recording. All patients showed dipole sources responsible for the PSWCs of CJD in both the cortical and subcortical deep gray matter. In five of six patients, the dorsolateral and medial frontal cortices were the cortical sources of the PSWCs. Four patients showed dipole sources in the caudate and/or lentiform nucleus. In three patients, the dipole source was localized in the thalamus. These findings suggest that basal ganglia and thalami, as well as frontal cortices, are involved in generating PSWCs in CJD.

Clinicopathologic characteristics of sporadic Japanese Creutzfeldt-Jakob disease classified according to prion protein gene polymorphism and prion protein type

We analyzed neuropathologic features of 23 Japanese patients with sporadic Creutzfeldt-Jakob disease (sCJD) by means of prion protein (PrP) immunolabeling associated with codon 129 polymorphism of the PrP gene and western blot analysis of protease-resistant PrP (PrP type). Clinical features, particularly age at onset, disease duration, periodic synchronous discharge and presence of myoclonus, were also analyzed. This study included 11 cases of subacute spongiform encephalopathy (SSE), 10 cases of panencephalopathic (PE)-type sCJD and two cases of thalamic-type sCJD, classified according to cerebral pathology findings. According to PrP gene polymorphism and PrP type, 18 cases were classified as MM1-type, two as MV1-type, two as MM2-type and one as MM1 + 2-type sCJD. SSE and PE-type sCJD showed similar clinical features, with the exception of disease duration, codon 129 polymorphism and PrP type. Thalamic-type sCJD showed different clinical features and PrP type. We suggest that SSE and PE-type sCJD comprise the sCJD subtype and that PE-type sCJD is a prolonged pathologic phenotype of SSE. When we compare our results with those from a series of Caucasian sCJD patients, the percentages of codon 129 polymorphisms differed, as did classification based on PrP gene polymorphism and PrP type; our series included many PE-type sCJD cases and disease duration was relatively long and MM2-type cases showed clinicopathologic variability.

MM2-thalamic-type sporadic Creutzfeldt-Jakob disease with widespread neocortical pathology

We report an autopsy case of MM2-thalamic-type sporadic Creutzfeldt-Jakob disease (sCJD) with widespread cerebral neocortical pathology. Initial symptoms were progressive insomnia and mental disturbance. Magnetic resonance imaging revealed no high-signal intensity lesions on diffusion-weighted images and later showed gradually progressive cerebral atrophy. Periodic synchronous discharges and myoclonus were not observed. Upon neuropathologic examination, widespread cerebral neocortical involvement with fine vacuole-type spongiform change was observed. Severe degeneration with almost complete neuronal loss, tissue rarefaction, numerous fat-laden macrophages and hypertrophic astrocytosis of the medial thalamic nucleus was evident. The inferior olivary nucleus showed severe involvement with neuronal loss and hypertrophic astrocytosis. In the cerebellar cortex, moderate depletion of Purkinje neurons was evident, with no spongiform change in the molecular layer and no neuronal loss in the granule cell layer. Immunohistochemistry for prion protein (PrP) revealed widespread synaptic-type deposits with some primitive plaque-type deposits in the cerebral neocortex, basal ganglia and cerebellar cortex. PrP deposition was also observed in the brainstem, particularly the tegmentum, substantia nigra and pontine nucleus, and spinal cord, particularly the posterior horn. In the medial thalamus and inferior olivary nucleus, PrP deposition was sparse. Analysis of the PrP gene showed no mutation but did show methionine homozygosity at polymorphic codon 129. Western blot analysis of protease-resistant PrP indicated the presence of type 2 PrP. We believe that this patient suffered from MM2-thalamic-type sCJD (sporadic fatal insomnia) with widespread cerebral neocortical pathology due to prolonged disease duration. The present case showed different patterns of spongiform degeneration and PrP deposition in the cerebral neocortex than those in previously reported MM2-thalamic-type sCJD cases.

Neuropathologic characteristics of spinal cord lesions in sporadic Creutzfeldt-Jakob disease

We investigated the neuropathologic features of spinal cord lesions in 23 patients with sporadic Creutzfeldt-Jakob disease (sCJD), paying particular attention to neuronal loss and gliosis, pyramidal tract degeneration and prion protein (PrP) deposition. The study included 9 cases of subacute spongiform encephalopathy, 13 cases of panencephalopathic-type sCJD and 1 case of sporadic fatal insomnia (sFI). In the spinal gray matter, although gliosis was present in some patients with disease of relatively long duration, the number of neurons, including large motor neurons, was well preserved regardless of disease duration. Pyramidal tract degeneration was observed in some patients with disease lasting more than 14 months but not in the patient with sFI. PrP deposition was present in the spinal cord of all sCJD patients, and was identified predominantly in the posterior horn, particularly in the substantia gelatinosa, regardless of disease duration or disease classification based on cerebral pathology. Relatively prominent PrP deposition was also observed in Clarke's column. The density of PrP deposition in the sCJD spinal cord was not associated with disease duration or neuronal degeneration. Our results indicate that PrP deposition in the spinal cord is an early pathologic event in sCJD and may remain to the end stage. Although no VV1, VV2 or MV2 cases were included in our study, we suggest that stereotypic accumulation of PrP is a consistent pathologic feature of sCJD and that the spinal cord remains relatively resistant to the pathologic process of sCJD, at least in patients with MM1 sCJD.