[Alterations in the WHO classification of brain tumors from 2016]. / Neuerungen der WHO­Klassifikation der Hirntumore von 2016.

BACKGROUND: The World Health Organization (WHO) provides uniform definitions and a uniform nomenclature for tumors of various organs. OBJECTIVE: What changes resulted from the 2016 WHO classification of tumors of the central nervous system? MATERIAL AND METHODS: Changes in the definition and classification of brain tumors of the revised WHO classification are presented. Most changes evolve from the results of molecular pathology that were generated during the last decade. RESULTS: For the first time the WHO classification of brain tumors is not based exclusively on histology. Molecular parameters add to the definition of a number of tumor entities. Especially the chapters of gliomas, medulloblastomas and other embryonal tumors have been restructured. CONCLUSION: Advances in molecular pathology require a modular diagnostics scheme that integrates histological and molecular parameters into a final diagnosis. This approach will result in more precise tumor groups with respect to prognosis and therapy.

[Requirements of neurologists for autopsies]. / Anforderungen des Neurologen an Obduktionen.

BACKGROUND: In assuring the quality of the healthcare system, it is the intention of healthcare politics to raise the number of clinical autopsies. OBJECTIVE: What are the requirements of clinical neurologists for neuroautopsies and how can the post-mortem examiner cope with these requests? METHODS: Discussion on how the questions that arise with the most relevant neurological disease groups can be solved by post-mortem examination. RESULTS: The diagnostics of inflammatory, inflammatory demyelinating and demyelinating brain diseases, neurodegenerative diseases and neuromuscular diseases as well as central nervous system tumors necessitate the removal of specific brain regions, specific examination techniques, immunohistochemical investigations or specific samples taken for biochemical, molecular pathological or genetic investigations according to international published consensus criteria. It is the first priority in post-mortem examinations to use all possible options and appraisals to identify patients with the aforementioned neurological diseases or suspected diseases early enough during the autopsy process that the tissue sampling, necessary for diagnosing the assumed diseases, will take place. CONCLUSION: Demands made on neuropathological investigations have increased tremendously, because of rapid progress in understanding chronic neurological diseases and the requirements of consensus criteria. To cope with expectations on neuropathological post-mortem investigations, a close collaboration should be established between clinical neurologists, post-mortem examiners and neuropathologists.

A proposal of new diagnostic pathway for fatal familial insomnia.

BACKGROUND: In absence of a positive family history, the diagnosis of fatal familial insomnia (FFI) might be difficult because of atypical clinical features and low sensitivity of diagnostic tests. FFI patients usually do not fulfil the established classification criteria for Creutzfeldt-Jakob disease (CJD); therefore, a prion disease is not always suspected. OBJECTIVE: To propose an update of diagnostic pathway for the identification of patients for the analysis of D178-M129 mutation. DESIGN AND METHODS: Data on 41 German FFI patients were analysed. Clinical symptoms and signs, MRI, PET, SPECT, polysomnography, EEG and cerebrospinal fluid biomarkers were studied. RESULTS: An algorithm was developed which correctly identified at least 81% of patients with the FFI diagnosis during early disease stages. It is based on the detection of organic sleep disturbances, either verified clinically or by a polysomnography, and a combination of vegetative and focal neurological signs and symptoms. Specificity of the approach was tested on three cohorts of patients (MM1 sporadic CJD patients, non-selected sporadic CJD and other neurodegenerative diseases). CONCLUSIONS: The proposed scheme may help to improve the clinical diagnosis of FFI. As the sensitivity of all diagnostic tests investigated but polysomnography is low in FFI, detailed clinical investigation is of special importance.

Hepatitis C virus enters human peripheral neuroblastoma cells - evidence for extra-hepatic cells sustaining hepatitis C virus penetration.

Patients with chronic hepatitis C virus (HCV) infection show an increased incidence of nervous system disorders such as chronic fatigue syndrome, depression and cognitive dysfunction. It is unclear whether this is because of HCV replication in the brain and in peripheral neuronal cells or to more indirect effects of HCV infection on the central or peripheral nervous system. The aim of this study was to investigate whether cells originating from these tissues are permissive for HCV cell entry, RNA replication and virus assembly. Among eight cell lines analysed, the human peripheral neuroblastoma cell line SKNMC expressed all HCV entry factors and was efficiently infected with HCV pseudoparticles (HCVpp) independent of the HCV genotype. All remaining cell types including human neuroblastoma and glioblastoma cell lines and microglial cells lacked expression of at least one host factor essential for HCV entry. When transfected with HCV luciferase reporter virus RNA, inoculated with HCV reporter viruses or challenged with high-titre cell culture-derived HCV, none of these cells supported detectable HCV RNA replication. Thus, in conclusion, this comprehensive screening did not reveal evidence directly strengthening the notion that HCV enters and replicates in the central nervous system. However, productive viral entry into the peripheral neuroblastoma cell line SKNMC indicates that HCV may penetrate into certain nonhepatic cell types which may serve as viral reservoirs and could modulate viral pathogenesis.

Alpha-synuclein seeds of Parkinson's disease show high prion-exceeding resistance to steam sterilization.

BACKGROUND: Cerebral deposition of abnormally misfolded and aggregated alpha-synuclein (αSyn) is a neuropathological hallmark of Parkinson's disease (PD). Pathologically aggregated αSyn species of PD (αSynPD) can act, in a 'prion-like' manner, as proteinaceous nuclei ('seeds') which are capable of self-templated propagation. This has raised concerns that αSynPD seeds transmitted iatrogenically between humans may stimulate αSyn pathologies or clinically harmful effects in the recipients. Effective decontamination when reprocessing medical devices could significantly counteract such risks. Steam sterilization at 134°C is recommended as an essential pathogen inactivation step in many reprocessing guidelines for medical devices, and also shows effectiveness against prions, the self-propagating biological agents long thought to exhibit the highest resistance to steam sterilization. METHODS: This study examined the reduction in αSynPD seeding activity in brain tissue homogenates from patients with PD after steam sterilization at 134°C using a specifically adapted real-time quaking induced conversion assay. FINDINGS: Titres of approximately 1010 50% seeding doses per gram were detected in non-steam-sterilized caudate nucleus tissue of patients with PD by endpoint titration. Five minutes of steam sterilization reduced this titre by only 2.25 ± 0.15 decadic-logarithmic units, with an extension of the sterilization time to 90 min not causing additional inactivation. These findings reveal that αSynPD species are disease-associated biological agents with seeding activity that has higher resistance to steam sterilization than prions. CONCLUSION: The remarkable heat resistance of αSynPD seeds calls for thoroughly validated cleaning and disinfection methods that reliably remove or inactivate possible contaminations of seeding-active αSyn aggregates when reprocessing medical devices.

Detection of classical and atypical/Nor98 scrapie by the paraffin-embedded tissue blot method.

The paraffin-embedded tissue (PET) blot method was used to investigate sections of the central nervous system and lymphatic tissues from 24 cases of classical scrapie and 25 cases of atypical/Nor98 scrapie in sheep and four healthy control sheep. The PET blot detected deposits of PrP(Sc) in the brain tissue of all 49 sheep with scrapie but no PrP(Sc) labelling could be detected in the control sheep. By contrast, not all the atypical/Nor98 scrapie cases were detectable by immunohistochemistry. The high sensitivity of the PET blot method made it possible to observe that in some atypical/Nor98 cases, deposits of PrP(Sc) may be restricted to supratentorial brain structures and that the diagnosis may be missed when only testing the obex area, where deposits are common in classical scrapie, and the cerebellar structures, where deposits are considered to be common in atypical/Nor98 cases.

MRI in the classical MM1 and the atypical MV2 subtypes of sporadic CJD: an inter-observer agreement study.

BACKGROUND AND PURPOSE: To establish radiological features in the atypical MV2 subtype of sCJD compared with the classical MM1 subtype, as well as region- and sequence-dependent inter-observer correlation. METHODS: MRI hyperintensity of basal ganglia (BG), cortex and thalamus was evaluated in 31 MM1 and 32 MV2 patients. Each MR scan was analyzed independently by two neuroradiologists blinded to PRNP genotype/prion protein type. RESULTS: Cumulative T2-sensitivity for BG hyperintensity was higher in the MV2 subtype (84% for both observers versus 61% in observer 1/42% in observer 2 in MM1 patients). Significant inter-observer agreement was found for BG and thalamus on T2, FLAIR, PD and DWI, but for cortex only on DWI. Thalamic changes were significantly more frequent in MV2 than in MM1 patients (cumulative sensitivity 86% vs. 12.5% on DWI). DISCUSSION: The high frequency of thalamic hyperintensity in the MV2 subtype allowed differentiation from MM1 patients. Good inter-observer agreement was found for BG and thalamus in all sequences. DWI showed the highest inter-observer correlation independent of the investigated brain region and was therefore not only highly sensitive but also relatively independent of investigator bias. Since inter-observer correlation for cortical hyperintensity in T2, FLAIR and PD is relatively low, the cortical changes should not be over-interpreted with these sequences.

Creutzfeldt-Jakob disease in Germany: a prospective 12-year surveillance.

Creutzfeldt-Jakob disease (CJD) is a rare and fatal neurodegenerative disorder with a worldwide incidence of 1-1.5 per million. As in other countries, a CJD surveillance unit with a clinical and neuropathological approach was established in Goettingen (Germany) in 1993. Here we report the epidemiological data from a prospective 12-year surveillance. Since 1993, there has been an increasing incidence of CJD, from 0.7 in 1993 to 1.6 in 2005 with a quite stable level since 1998. During this period, the proportion of patients with MV and VV codon 129 genotype rose, possibly because of better identification of atypical subtypes. Six percent of all patients had a PRNP mutation, mainly D178N-129M (FFI), E200K and V210I. Iatrogenic CJD was a rare phenomenon. No patient infected by cadaveric growth hormone extracts was reported. Furthermore, no variant CJD patient has yet been identified in Germany. Differential diagnoses revealed a variety of neurodegenerative diseases, with Alzheimer's disease in the lead. One-third of the non-CJD patients included in this study suffered from a potentially treatable disorder such as metabolic or inflammatory diseases. The incidence and mortality rates in Germany are similar to those in other European countries. In contrast, however, acquired forms, such as iatrogenic and variant CJD are still rare in Germany or have not yet been identified.

TorsinB expression in the developing human brain.

Familial, early onset, generalized torsion dystonia is the most common and severe primary dystonia. The majority of cases are caused by a 3-bp deletion (GAG) in the coding region of the DYT1 (TOR1A) gene. The cellular and regional distribution of torsinA protein, which is restricted to neuronal cells and present in all brain regions by the age of 2 months has been described recently in human developing brain. TorsinB is a member of the same family of proteins and is highly homologous with its gene adjacent to that for torsinA on chromosome 9q34. TorsinA and torsinB share several remarkable features suggesting that they may interact in vivo. This study examined the expression of torsinB in the human brain of fetuses, infants and children up to 7 years of age. Our results indicate that torsinB protein expression is temporarily and spatially regulated in a similar fashion as torsinA. Expression of torsinB protein was detectable beginning at four to 8 weeks of age in the cerebellum (Purkinje cells), substantia nigra (dopaminergic neurons), hippocampus and basal ganglia and was predominantly restricted to neuronal cells. In contrast to torsinA, torsinB immunoreactivity was found more readily in the nuclear envelope. High levels of torsinB protein were maintained throughout infancy, childhood and adulthood suggesting that torsinB is also needed for developmental events occurring in the early postnatal phase and is necessary for functional activity throughout life.

Creutzfeldt-Jakob disease: comparative analysis of MR imaging sequences.

BACKGROUND AND PURPOSE: MR imaging has played an increasingly important role in the diagnosis of Creutzfeldt-Jakob disease (CJD) since basal ganglia abnormalities on T2-weighted images have been described; thus, the aim of our study was to compare the value of different MR images in the diagnosis of CJD. METHODS: One hundred fifty-seven patients with CJD underwent MR imaging examinations. Ninety-two patients were neuropathologically confirmed, and 65 were clinically classified as having CJD through the CJD Surveillance Unit (probability of 95%). There was no standardized MR imaging protocol; thus, the examinations included 143 T2-weighted, 43 proton attenuation (PD)-weighted, 84 fluid-attenuated inversion recovery (FLAIR), and 44 diffusion-weighted images (DWI). The MR images were reviewed for pathologic changes of the basal ganglia, thalamus, and cerebral cortex. RESULTS: Cortical abnormalities were present in 70 patients (45%) and were visible in 80% (35/44) of all available DWI examinations. The basal ganglia were affected in 94 patients (60%), in particular in the caudate nucleus; the most sensitive sequences were DWI (64%) and PD-weighted (63%). A thalamic involvement was more frequently diagnosed on PD-weighted images (19%) and DWI (14%) than on FLAIR or T2-weighted images. CONCLUSION: PD-weighted images and DWI showed better results in the diagnosis of signal intensity changes in the basal ganglia compared with T2-weighted or FLAIR images; however, in the diagnosis of cortical changes, DWI was clearly superior. Our data suggest that DWI is the most sensitive MR imaging technique in the diagnosis of CJD.

Pathophysiological Concepts and Treatment of Camptocormia.

Camptocormia is a disabling pathological, non-fixed, forward bending of the trunk. The clinical definition using only the bending angle is insufficient; it should include the subjectively perceived inability to stand upright, occurrence of back pain, typical individual complaints, and need for walking aids and compensatory signs (e.g. back-swept wing sign). Due to the heterogeneous etiologies of camptocormia a broad diagnostic approach is necessary. Camptocormia is most frequently encountered in movement disorders (PD and dystonia) and muscles diseases (myositis and myopathy, mainly facio-scapulo-humeral muscular dystrophy (FSHD)). The main diagnostic aim is to discover the etiology by looking for signs of the underlying disease in the neurological examination, EMG, muscle MRI and possibly biopsy. PD and probably myositic camptocormia can be divided into an acute and a chronic stage according to the duration of camptocormia and the findings in the short time inversion recovery (STIR) and T1 sequences of paravertebral muscle MRI. There is no established treatment of camptocormia resulting from any etiology. Case series suggest that deep brain stimulation (DBS) of the subthalamic nucleus (STN-DBS) is effective in the acute but not the chronic stage of PD camptocormia. In chronic stages with degenerated muscles, treatment options are limited to orthoses, walking aids, physiotherapy and pain therapy. In acute myositic camptocormia an escalation strategy with different immunosuppressive drugs is recommended. In dystonic camptocormia, as in dystonia in general, case reports have shown botulinum toxin and DBS of the globus pallidus internus (GPi-DBS) to be effective. Camptocormia in connection with primary myopathies should be treated according to the underlying illness.

TorsinA expression is detectable in human infants as young as 4 weeks old.

Familial, early onset, generalized torsion dystonia is the most common and severe primary dystonia. The majority of cases are caused by a 3-bp deletion (GAG) in the coding region of the DYT1 (TOR1A) gene. The cellular and regional distribution of torsinA protein and its message has been described previously in several regions of normal adult human and rodent brain. This study examines the expression of torsinA in the developing human brain of fetuses, infants and children up to 7 years of age in four selected brain regions. Expression of torsinA protein was detectable beginning at 4 to 8 weeks of age postnatally in the cerebellum (Purkinje cells), substantia nigra (dopaminergic neurons), hippocampus and basal ganglia. Prominent torsinA immunoreactivity was not seen before 6 weeks of age postnatally, a period associated with synaptic remodeling, process elimination and the beginning of myelination. Our results indicate that torsinA protein expression is temporally and spatially regulated and is present in all brain regions studied by the age of 2 months on into adulthood.

The Heidenhain variant of Creutzfeldt-Jakob disease.

OBJECTIVE: To investigate whether typical neuropathological and radiological findings can be identified in patients with the clinical diagnosis of the Heidenhain variant of Creutzfeldt-Jakob disease (CJD). DESIGN: Case study. The clinical symptoms, neuropathological findings, electroencephalograms, magnetic resonance images, and cerebrospinal fluid samples of 14 Heidenhain cases were evaluated. Neuropathological changes were compared with those in a group of 14 patients with ataxia as the leading clinical sign. SETTING: A university hospital, base of the German National Creutzfeldt-Jakob Disease Surveillance Study. PATIENTS: Medical records of 169 neurologically examined patients with prospectively classified and neuropathologically confirmed CJD were analyzed. MAIN OUTCOME MEASURE: Difference in neuropathological and radiological findings between patients with the Heidenhain variant and other patients with CJD. RESULTS: Of 169 patients with confirmed CJD, 20% showed characteristic clinical findings such as blurred vision, visual field restriction, metamorphopsia, or cortical blindness. Disease course of the Heidenhain group, as compared with the group of all patients with definite CJD, was significantly shorter (5.7 months vs 7.5 months; P=.02, t test). Neuropathological examination of patients with the Heidenhain variant showed most pronounced changes in the occipital lobe but less damage in the cingulate gyrus and basal ganglia compared with 14 patients with CJD who had ataxia as the leading clinical sign. Eleven (92%) of 12 genetically analyzed Heidenhain cases were homozygous for methionine at codon 129 of the prion protein gene (PRNP). In 9 of 9 cases, the 14-3-3 protein was present. In 7 (78%) of 9 cases, the level of neuron-specific enolase was elevated, with a concentration above 35 ng/mL. Periodic sharp-wave complexes were observed in 11 (78%) of the 14 cases. In 7 (63%) of 11 patients, magnetic resonance images showed symmetric hyperintensities in the basal ganglia in the T2- and proton-weighted sequence. In 4 of 11 cases the T2- and proton density-weighted images showed a pronounced signal increase confined to the gray matter of the occipital and visual cortex. Isolated atrophy of the visual cortex was noticeable in 2 of 11 cases. CONCLUSIONS: The clinical presentation of the Heidenhain variant of CJD was shown to correlate with the neuropathological findings of gliosis and nerve cell loss. In patients with visual disorders of unclear origin and signs of dementia, the differential diagnosis of a Heidenhain variant of CJD must be taken into consideration.

Detection of PrP(Sc) in subclinical BSE with the paraffin-embedded tissue (PET) blot.

The appearance of a new variant of CJD (vCJD) in young patients has caused considerable public concern and there is evidence that this novel disease is caused by the same agent as BSE. BSE is a prion disease that became epidemic in the UK, with a peak incidence in January 1993. New test systems should aim to identify BSE-infected cattle early in the incubation period. We compared the established histological and immunohistochemical methods and the Western blot method used by Prionics with the PET blot method that detects prion PrP(Sc) deposits in formalin-fixed and paraffin-embedded tissue. Investigating the obex region with the PET blot, all BSE cases were detectable and no false positive cases occurred. From the Swiss culling program, five clinically healthy cattle out of 1761 were identified as incubating BSE. With the PET blot method four of them showed the same PrP(Sc) deposition pattern that was seen in clinical BSE, though less conspicuous. In one of the five cases, PrP(Sc) was restricted to two brain stem nuclei, a pattern that was reported to be the first manifestation of PrP(Sc) deposits in the brain after peripheral infection and one that occurs after half of the incubation time. In this case, histology and Western blot were negative.

Early age of onset in fatal familial insomnia. Two novel cases and review of the literature.

Fatal familial insomnia (FFI) is a prion disease exhibiting the PRNP D178N/129M genotype. Features of this autosomal dominant illness are progressive insomnia, dysautonomia, myoclonus, cognitive decline and motor signs associated with thalamic nerve cell loss and gliosis. In contrast to the new variant of Creutzfeldt-Jakob disease (vCJD) the onset of FFI is in middle to late adulthood. We report two male patients who belong to a large German FFI kindred. They were examined clinically, and postmortem neuropathological examination was carried out in collaboration with the German reference centre for prion disease. Additionally, the prion protein gene (PRNP) was analysed. To identify further patients with disease onset under 30 years of age a comprehensive literature review was carried out. Two male patients presented with typical symptoms of FFI at the age of 23 and 24 years. In their kindred, the age of onset has never before been under 44 years of age. Our literature review identified five additional early onset cases who died at age 21 to 25 years. In all 22 reviewed FFI families the median manifestation age was 49.5 years. Although phenotypic variability of FFI is common, age of onset under 30 years has been considered to be a hallmark of vCJD with a mean manifestation at 27 years of age. Our findings underline that in addition to vCJD, FFI must be considered in cases of young-onset prion disease. This has considerable impact on clinical management and genetic counselling.

Increase of neuron-specific enolase in patients with Creutzfeldt-Jakob disease.

Creutzfeldt-Jakob disease (CJD) is a rare neurodegenerative human disorder with an incidence of one case per 1000000 per year. Recently new diagnostic tests such as neuron-specific enolase (NSE), S-100, tau-protein and protein 14-3-3 have been established as markers in prion diseases. NSE is elevated in case of rapid nerve cell loss so quantitative measurement of NSE in cerebrospinal fluid (CSF) might correlate with the disease progression. To further evaluate this hypothesis we analysed longitudinal CSF samples from 16 CJD patients. The first spinal tap was taken two weeks after the first clinical signs of a neurodegenerative disorder. This showed an elevation of NSE which continued during the course of the disease. Longitudinal examination of neuron-specific enolase in cerebrospinal fluid therefore may be useful for differentiation between CJD and other dementias.

Postmortem delay and temperature conditions affect the in situ end-labeling (ISEL) assay in brain tissue of mice.

Apoptotic cell changes occurring under certain developmental, physiological, and pathological conditions have been of increasing interest during recent years. Due to occasional difficulties in detecting apoptosis in routinely stained sections, various methods have been developed to facilitate tissue examination. Fragmentation of DNA during the process of apoptosis is a prerequisite for detection in the in situ end-labeling (ISEL) procedure. It is yet unclear whether other mechanisms of cell change that induce DNA fragmentation such as necrosis and postmortem autolysis also show positive staining with the ISEL technique. To investigate whether the ISEL assay visualizes autolytic DNA changes along with apoptotic DNA fragmentation, we tested the technique on brain tissue of mice after different time intervals (0, 6, 12, 24, 48, 72 h) of postmortem delay (PMD) and at 2 different temperatures of postmortem storage (4 degrees C and room temperature (RT)). Our semiquantitative results show that up to 24 h of PMD no prominent difference in labeling is observable at both temperatures. After 48 and 72 h of PMD at RT clusters of labeled cells begin to appear. Clusters of stained cells should therefore not be considered as apoptosis when using the ISEL assay.

Polymorphism at codon 129 of the prion protein gene determines cerebellar pathology in Creutzfeldt-Jakob disease.

Creutzfeldt-Jakob disease (CJD) is a transmissible neurodegenerative disorder characterized by the accumulation of proteinase-resistant prion protein (PrP) in the brain. Pathological changes in the cerebellum are common and include atrophy of the granular layer, spongiform change in the molecular layer, and astrocytic gliosis of the cerebellar cortex and white matter. In most cases of sporadic CJD immunohistochemistry for PrP shows widespread granular deposits of the scrapie isoform of the prion protein (PrPSc) in the cerebellar cortex. In a minority of cases plaque-like deposits of PrPSc are detectable. The genetic background of this phenomenon was investigated in 47 cases of sporadic CJD. Immunohistochemistry using antibodies against PrP was performed in brain autopsy specimens. A genetic analysis of the prion protein gene (PRNP) showed overrepresentation of homozygosity for either methionine (M/M) or valine (V/V) at the polymorphic codon 129 in CJD patients as compared to 74 controls. No significant difference in allele frequency between the 2 groups was found. Plaques or plaque-like PrPSc deposits were found in 9 cases of CJD and were associated with the presence of valine at codon 129 on at least 1 allele of PRNP. CJD patients homozygous for valine (V/V) were on an average more than 5 years younger than patients with M/M or M/V at codon 129.

Mixed Glioma (Oligoastrocytoma) in the brain of an African Hedgehog (Atelerix albiventris).

This report describes an oligoastrocytoma in the brain of a 3.5-year-old female pet African hedgehog (Atelerix albiventris) that showed progressive central nervous system signs for 6 months. Microscopical examination of the brain revealed a widely infiltrative, deep-seated glioma within the white matter of the cerebral hemispheres, basal nuclei, hippocampus, thalamus, midbrain, pons and the medulla of the cerebellum with extension of neoplastic cells into the cerebral cortex and overlying leptomeninges. Morphological features of the neoplastic cells, together with variable immunohistochemical expression of glial fibrillary acidic protein, Olig-2 and Nogo-A, indicated the presence of intermingled astrocytic and oligodendroglial tumour cells with an astrocytic component of approximately 40% consistent with an oligoastrocytoma. The distribution of the tumour is consistent with gliomatosis cerebri.