[Hereditary diffuse leukencephalopathy with spheroids: a microgliopathy due to CSF1 receptor impairment]. / Hereditäre diffuse Leukenzephalopathie mit Sphäroiden : Eine Mikrogliopathie durch Fehlfunktion des CSF1-Rezeptors.

Hereditary diffuse leukencephalopathy with spheroids (HDLS) is a rare progressive form of leukodystrophy with variable clinical presentation and little known pathophysiology. Characteristic pathological features at brain biopsy or postmortem can support the diagnosis. The genetic basis of HDLS was elusive until 2011 when mutations in the colony-stimulating factor 1 receptor (CSF1R) gene were identified as the cause. Mutations in the CSF1R gene had previously been associated with tumor development, including hematological malignancies. We report three patients with HDLS who carried missense mutations in the CSF1R gene, two of them novel (p.L582P and p.V383L). Particularly in younger patients with rapid cognitive decline and/or leukencephalopathy of unknown origin, HDLS appears to be more common than previously thought. Various compounds acting on the CSF1 receptor are available from the treatment of hemato-oncological malignancies, so novel therapeutic approaches could be developed for this devastating condition.

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.

[Molecular biological identification of fungal pathogens in FFPE tissue from cases of cephalic mycosis]. / Molekularbiologischer Erregernachweis aus FFPE-Proben bei zephaler Mykose.

BACKGROUND: Due to the lack of histopathological differentiation the unequivocal identification of fungal pathogens is rarely possible. In order to understand the pathogen spectrum causing cephalic mycosis the use of alternative methods is essential. MATERIAL AND METHODS: In a retrospective study 24 formalin-fixed, paraffin-embedded (FFPE) samples from patients with histologically confirmed cerebral or cephalic mycosis were analyzed with molecular biological methods. RESULTS: In two samples obtained during the patients' lifetime human as well as fungal DNA was detected, making an unambiguous diagnosis possible. For tissue that had been fixed over a longer period, detection of human and fungal DNA was possible merely in 60% and 47 % of the samples, respectively. Most frequently diagnosed were aspergillosis (n = 9), followed by mucormycosis (n = 2) and imported blastomycosis (n = 1). CONCLUSIONS: Using biopsy material a DNA analysis seems promising although only with limited success using brain samples taken at autopsy which have been fixed over a longer period. For unambiguous retrospective diagnostics of pathogens when cephalic mycosis is suspected, the sample extraction for postmortem diagnostics should be performed prior to a long period of formalin fixation.

Influence of the blood-CSF-barrier function on S100B in neurodegenerative diseases.

OBJECTIVES: S100B was proposed to be a CSF and blood biomarker in a number of neurological diseases. The route of S100B to the CSF and the blood in neurodegenerative diseases is unclear. To assess the impact of the physiological or impaired blood-CSF-barrier (BCSFB) function on S100B concentrations in CSF and serum, we analysed S100B in correlation of the albumin quotient. MATERIALS AND METHODS: S100Bserum and S100BCSF were quantified in samples from patients with a variety of neurological diseases using an immunoluminometric assay (Sangtec LIA-mat). Measures were analysed for a potential relation to the CSF/serum-albumin quotient (Qalb ), which indicates the BCSFB functionality. RESULTS: We reasserted increased S100B concentrations in CSF and serum of CJD patients. Elevated S100Bserum correlated with elevated S100BCSF in all diagnoses but with exceptions. Neither S100BCSF nor S100Bserum did correlate with Qalb , even when the BCSFB function was progressively impaired as demonstrated by increased Qalb . CONCLUSIONS: The lack of correlation between Qalb and S100BCSF is typically seen for proteins which are brain derived. Therefore, we propose that S100B enters the blood with the bulk flow via Pacchioni's granules and along the spinal nerve sheaths.

Recruitment of neural precursor cells from circumventricular organs of patients with cerebral ischaemia.

AIMS: Adult neurogenesis is well described in the subventricular zone of the lateral ventricle walls and in the subgranular zone of the hippocampal dentate gyrus. However, recent studies indicate that self-renewal of neural stem cells (NSCs) is not restricted to these niches, but that diverse areas of the adult brain are capable of generating new neurones and responding to various pathological alterations. In particular, NSCs have been identified in circumventricular organs (CVOs) of the adult mouse brain. METHODS: In order to detect possible neural stem or progenitor cells in CVOs of the human brain, we analysed post mortem human brain tissue from patients without neuropathological changes (n = 16) and brains from patients with ischaemic stroke (n = 16). RESULTS: In all analysed CVOs (area postrema, median eminence, pineal gland and neurohypophysis) we observed cells with expression of early NSC markers, such as GFAP, nestin, vimentin, OLIG2 and PSA-NCAM, with some of them coexpressing Ki67 as a marker of cell proliferation. Importantly, stroke patients displayed an up to fivefold increase with respect to the relative number of Ki67- and OLIG2-expressing cells within their CVOs. CONCLUSIONS: Our findings are compatible with a scenario where CVOs may serve as a further source of NSCs in the adult human brain and may contribute to neurogenesis and brain plasticity in the context of brain injury.

[German consortium for frontotemporal lobar degeneration]. / Konsortium zur Erforschung der frontotemporalen Lobärdegeneration.

Frontotemporal lobar degeneration (FTLD) is an umbrella term for an aetiologically diverse group of neurodegenerative disorders with prominent lobar cortical atrophy. First this disease group was restricted to Pick's disease or Pick's complex. Several updates of the clinical classification systems were performed and discussed. Currently we summarize the following diseases under the FTLD spectrum: frontotemporal dementia (FTD) as a behavioural variant, primary non-fluent aphasia (PNFA) and semantic dementia as language variants, amyotrophic lateral sclerosis with FTD (ALS-FTD), corticobasal syndrome (CBS) and progressive supranuclear palsy (PSP).From the pathophysiological aspect major progress was made. Neuropathologically FTLDs are now defined based on the molecular composition of these protein accumulations. A major distinction of tau-associated (FTLD-tau) and TDP43-associated (FTLD-TDP43) and to a lesser extend FUS-associated (FTLD-FUS) has been made. Additional risk genes were described. However from the therapeutic perspective even symptomatic therapy is under discussion. A major aim of our consortium is to develop parameters allowing an early diagnosis and follow-up, thus providing effective and objective parameters for therapeutic strategies.

Expression of BARHL1 in medulloblastoma is associated with prolonged survival in mice and humans.

Medulloblastoma is the most common malignant brain tumor in childhood, and development of targeted therapies is highly desired. Although the molecular mechanisms of malignant transformation are not fully understood, it is known that medulloblastomas may arise from cerebellar granule neuron precursors. The homeodomain transcription factor Barhl1 is known to regulate migration and survival of granule cell precursors, but its functional role in medulloblastoma is unknown. We show here that the expression of BARHL1 is significantly upregulated during human cerebellar development and in human medulloblastoma samples as compared with the normal adult cerebellum. We also detected high levels of Barhl1 expression in medulloblastomas of Math1-cre:SmoM2 mice, a mouse model for Sonic hedgehog-associated medulloblastomas that we developed previously. To investigate Barhl1 function in vivo during tumor development, we generated Barhl1(-/-)Math1-cre:SmoM2 mice. Interestingly, tumors that developed in these mice displayed increased mitotic activity and decreased neuronal differentiation. Moreover, survival of these mice was significantly decreased. Similarly, low expression of BARHL1 in human medulloblastoma cases was associated with a less favorable prognosis for patients. These results suggest that the expression of Barhl1 decelerates tumor growth both in human and in murine medulloblastomas and should be further investigated with respect to potential implications for individualized therapeutic strategies.

Hot spots in dynamic (18)FET-PET delineate malignant tumor parts within suspected WHO grade II gliomas.

Molecular imaging studies have recently found inter- and intratumoral heterogeneity in World Health Organization (WHO) grade II gliomas. A correlative analysis with tumor histology, however, is still lacking. For elucidation we conducted the current prospective study. Fifty-five adult patients with an MRI-based suspicion of a WHO grade II glioma were included. [F-18]Fluoroethyltyrosine ((18)FET) uptake kinetic studies were combined with frame-based stereotactic localization techniques and used as a guide for stepwise (1-mm steps) histopathological evaluation throughout the tumor space. In tumors with heterogeneous PET findings, the O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation status and expression of mutated protein isocitrate dehydrogenase variant R132H (IDH1) were determined inside and outside of hot spot volumes. Metabolic imaging revealed 3 subgroups: the homogeneous WHO grade II glioma group (30 patients), the homogeneous malignant glioma group (10 patients), and the heterogeneous group exhibiting both low- and high-grade characteristics at different sites (15 patients). Stepwise evaluation of 373 biopsy samples indicated a strong correlation with analyses of uptake kinetics (p < 0.0001). A homogeneous pattern of uptake kinetics was linked to homogeneous histopathological findings, whereas a heterogeneous pattern was associated with histopathological heterogeneity; hot spots exhibiting malignant glioma characteristics covered 4-44% of the entire tumor volumes. Both MGMT and IDH1 status were identical at different tumor sites and not influenced by heterogeneity. Maps of (18)FET uptake kinetics strongly correlated with histopathology in suspected grade II gliomas. Anaplastic foci can be accurately identified, and this finding has implications for prognostic evaluation and treatment planning.

Automated decontamination of surface-adherent prions.

At present there is no routinely available decontamination procedure in washer-disinfectors to allow the reliable inactivation and/or elimination of prions present on reusable surgical instruments. This means that is not possible to provide assurance for preventing iatrogenic transmission of prion diseases. We need effective procedures in prion decontamination that can be integrated into the usual routine of reprocessing surgical instruments. This article reports on the evaluation of an automated process designed to decontaminate prions in washer-disinfectors using a quantitative, highly sensitive in vivo assay for surface-adherent 22L prions. The automated process showed great advantages when compared with conventional alkaline cleaning. In contrast, the new process was as effective as autoclaving at 134 degrees C for 2h and left no detectable prion infectivity, even for heavily contaminated surfaces. This indicates a reduction of surface-adherent prion infectivity of >7 log units. Due to its compatibility with even delicate surgical instruments, the process can be integrated into the large scale reprocessing of instruments in a central sterile supply department. The system could potentially make an important contribution to the prevention of iatrogenic transmission of prions.

MRI and clinical syndrome in dura mater-related Creutzfeldt-Jakob disease.

OBJECTIVE: Iatrogenic Creutzfeldt-Jakob disease (iCJD) is mainly associated with dura mater (DM) grafts and administration of human growth hormones (hGH). Data on disease course in DM-CJD are limited. We describe the clinical and diagnostic findings in this patient group with special emphasis on MRI signal alterations. METHODS: Ten DM-CJD patients were studied for their clinical symptoms and diagnostic findings. The MRIs were evaluated for signal increase of the cortical and subcortical structures. RESULTS: DM-CJD patients had a median incubation time of 18 years and median disease duration of 7 months. The majority of patients were MM homozygous at codon 129 of the prion protein gene (PRNP) and presented with gait ataxia and psychiatric symptoms. No correlation between the graft site and the initial disease course was found. The MRI showed cortical and basal ganglia signal increase each in eight out of ten patients and thalamic hyperintensity in five out of ten cases. Of interest, patients with thalamic signal increase were homozygous for methionine. CONCLUSION: The MRI findings in DM-CJD largely resemble those seen in sporadic CJD, as the cortex and basal ganglia are mainly affected.

14-3-3 CSF levels in sporadic Creutzfeldt-Jakob disease differ across molecular subtypes.

BACKGROUND: The 14-3-3 protein is a physiological cellular protein expressed in various tissues, and its release to CSF reflects extensive neuronal damage as in Creutzfeldt-Jakob disease (CJD), but also in other neurological diseases. 14-3-3 protein in CSF in the proper clinical context is a reliable diagnostic tool for sporadic CJD. However, the sensitivity varies across molecular CJD subtypes. OBJECTIVE: We determined the level of the 14-3-3 protein in CSF from 70 sporadic CJD patients with distinct molecular subtypes using an improved enzyme-linked immunosorbent assay (ELISA) protocol technique. RESULTS: The 14-3-3 levels varied markedly across various molecular subtypes. The most elevated levels of 14-3-3 protein were observed in the frequently occurring and classical subtypes, whereas the levels were significantly lower in the subtypes with long disease duration and atypical clinical presentation. PRNP codon 129 genotype, PrP(sc) isotype, disease stage and clinical subtype influenced the 14-3-3 level and the test sensitivity. CONCLUSIONS: The 14-3-3 protein levels differ across molecular subtypes and might be used for their early pre-mortem identification when the codon 129 genotype is known, especially for the less common molecular subtypes such as MV2 and MM2.

[Molecular neuropathology of Non-Alzheimer dementia]. / Molekulare Neuropathologie der Nicht-Alzheimer-Demenzen.

The increasing life expectancy will cause an increasing share for neurodegenerative and dementing illnesses in the total cost for health care. New developments such as the discovery of TDP-43 as disease protein have opened new viewpoints on frontotemporal dementias, as well as its relation to amyotrophic lateral sclerosis. As pathologists and neuropathologists we are committed to contributing to the progress of clinical diagnosis, which often proves difficult, by standardized post-mortem diagnosis. The diagnostic responsibility will increase with the development of new specific therapeutics and knowledge of contraindications such as the use of neuroleptics in patients suffering from Lewy body dementia. The Reference Center for Neurodegenerative Diseases of the German Society of Neuropathology and Neuroanatomy and the German Brain Bank (Brain-Net) at the Institute for Neuropathology, Ludwig-Maximilians-University Munich, are available for diagnosis in difficult or complex 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.

[Fatal familial insomnia--a rare differential diagnosis in dementia]. / Letale familiäre Insomnie--Eine seltene Differenzialdiagnose in der Demenzabklärung.

Fatal familial insomnia (FFI)--first reported in 1986--is a hereditary prion disease with autosomal-dominant inheritance, caused by a missense-mutation at codon 178 of the prion-protein gene (PRNP) on chromosome 20. A methionine-valine polymorphism at codon 129 of PRNP expresses different phenotypes. The clinical features of FFI are characterized by a disrupted sleep-wake cycle with resulting fluctuations of vigilance, autonomic hyperactivation, myoclonus, motor abnormalities and by cognitive disturbances. The age of onset is between middle to late adulthood (51 +/- 7.1 years), disease duration varies between 8 and 72 months (18.4 +/- 17.3 months) and is ultimately fatal. We report the case of a 57-year-old man with a diagnosed FFI by molecular-genetic investigation who suffered from increasing memory- and sleep-disturbance as well as physical restlessness and impotence for 9 months. Clinical features were motor symptoms, generalized myoclonus and hyperactivity with reduced attention and concentration. The neuropsychological findings were a severe disturbance of attention and memory as well as incipient deficits in executive functions. The cranial MRI and repeated EEG were normal; in detailed laboratory tests including CSF no abnormalities were detected. The clinical course was characterized by rapid decline of the motor and cognitive skills; the patient died 15 months after onset. Histological analysis showed the typical changes of FFI (spongiform changes at hippocampus and regio entorhinalis, severe gliosis in the thalamus and mild deposits of abnormal prion protein).

Pattern of cortical changes in sporadic Creutzfeldt-Jakob disease.

BACKGROUND AND PURPOSE: High cortical signal intensity on diffusion-weighted (DW) or fluid-attenuated inversion recovery (FLAIR) images is increasingly described in sporadic Creutzfeldt-Jakob disease (sCJD). The aim of this study was to assess the extent and location of high cortical signal intensity, to investigate whether DW or FLAIR is superior in showing changes in cortical signal intensity, and to find out whether the distribution of the signal intensity changes is random or follows a common pattern. MATERIALS AND METHODS: We analyzed FLAIR and DW MR imaging scans of 39 patients with sCJD for hyperintense cortical signal intensity. We compared the sensitivity of the DW and FLAIR scans. We correlated the extent and location of the cortical signal intensity changes with concomitant changes in deep gray matter and the genotype of codon 129 of the prion protein gene. RESULTS: There was high signal intensity in the insula, the cingulate gyrus, and the superior frontal gyrus in 95%. The cortical areas near the midline also frequently showed the abnormal signal intensity (precuneus 87%, paracentral lobe 77%). The precentral and postcentral gyri were affected less frequently (41% and 28%, respectively). The DW MR imaging showed the cortical changes more effectively than FLAIR. There was no correlation between the distribution of changes and additional signal alterations in deep gray matter or the genotype of codon 129. CONCLUSION: The distribution of cortical signal intensity abnormalities in patients with sCJD follows a common pattern, affecting mainly the cortical areas near the midline, the insula, cingulum, and the superior frontal cortex. DW imaging is superior to FLAIR in the detection of cortical high signal intensity.

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.

Significant association of a M129V independent polymorphism in the 5' UTR of the PRNP gene with sporadic Creutzfeldt-Jakob disease in a large German case-control study.

BACKGROUND: A single nucleotide polymorphism (SNP) in the coding region of the prion protein gene (PRNP) at codon 129 has been repeatedly shown to be an associated factor to sporadic Creutzfeldt-Jakob disease (sCJD), but additional major predisposing DNA variants for sCJD are still unknown. Several previous studies focused on the characterisation of polymorphisms in PRNP and the prion-like doppel gene (PRND), generating contradictory results on relatively small sample sets. Thus, extensive studies are required for validation of the polymorphisms in PRNP and PRND. METHODS: We evaluated a set of nine SNPs of PRNP and one SNP of PRND in 593 German sCJD patients and 748 German healthy controls. Genotyping was performed using MALDI-TOF mass spectrometry. RESULTS: In addition to PRNP 129, we detected a significant association between sCJD and allele frequencies of six further PRNP SNPs. No significant association of PRND T174M with sCJD was shown. We observed strong linkage disequilibrium within eight adjacent PRNP SNPs, including PRNP 129. However, the association of sCJD with PRNP 1368 and PRNP 34296 appeared to be independent on the genotype of PRNP 129. We additionally identified the most common haplotypes of PRNP to be over-represented or under-represented in our cohort of patients with sCJD. CONCLUSION: Our study evaluated previous findings of the association of SNPs in the PRNP and PRND genes in the largest cohorts for association study in sCJD to date, and extends previous findings by defining for the first time the haplotypes associated with sCJD in a large population of the German CJD surveillance study.

Breaking an absolute species barrier: transgenic mice expressing the mink PrP gene are susceptible to transmissible mink encephalopathy.

Transmissible mink encephalopathy (TME) is a rare disease of the North American mink, which has never been successfully transmitted to laboratory mice. We generated transgenic mice expressing the mink prion protein (PrP) and inoculated them with TME or the mouse-adapted scrapie strain 79A. TME infected mink PrP-transgenic mice on a murine PrP knockout background. The absolute species barrier between the infectious agent of TME and mice was therefore broken. Following TME and 79A infection of mice carrying both mink and murine PrP(C), only proteinase-resistant PrP homologous to the incoming agent was detectable. The presence of the murine PrP(C) prolonged the incubation time of TME substantially.

Sporadic Creutzfeldt-Jakob disease: clinical and diagnostic characteristics of the rare VV1 type.

BACKGROUND: Recently, six molecular subtypes of sporadic CJD (sCJD) have been identified showing differences regarding the disease course, neuropathologic lesion patterns, and sensitivity to diagnostic tools. Only isolated cases of the rare VV1 type have been reported so far. OBJECTIVE: To describe the clinical characteristics and neuropathologic lesion profiles in nine cases. METHODS: In the years 1993 until late 2003, 571 definite neuropathologically confirmed cases of sporadic CJD were identified in Germany. Of these, nine were homozygous for valine and displayed type 1 of the pathologic PrPSc in the brain (VV1 type). RESULTS: The authors describe eight men and one woman belonging to the VV1 type. All patients were relatively young at disease onset (median 44 years vs 65 years in all sCJD) with prolonged disease duration (median 21 months vs 6 months in all sCJD). During the initial stages, their main clinical signs were personality changes and slowly progressive dementia as well as focal neurologic deficits. None of the nine VV1 patients had periodic sharp-wave complexes (PSWCs) in the EEG. Only two out of seven displayed the typical signal increase of the basal ganglia on MRI, whereas signal increase of the cortex was seen in all patients. The 14-3-3 protein levels were elevated in CSF in all cases tested. CONCLUSIONS: The clinical diagnosis of the VV1 type of sCJD can be best supported by the 14-3-3 test and cortical signal increase on MRI. Because of the young age at onset vCJD is sometimes suspected as a differential diagnosis. MRI plays an important role in differentiating these two disease types and should be performed early during the disease course.