Brain biopsy in suspected non-neoplastic neurological disease.

Brain biopsy has a well-established role in the diagnosis of CNS neoplasia. Nevertheless, despite being essential for the diagnosis of some benign neurological diseases, little consensus exists regarding its indications for disease diagnosis and patient orientation. Our aim was to assess brain biopsy diagnostic yield in patients with neurological deterioration of unknown etiology, to identify the clinical characteristics associated with an increased likelihood of achieving a diagnostic biopsy as well as the characteristics linked to a particular diagnosis. METHODS: A retrospective analysis of 62 consecutive brain biopsies performed at a single tertiary care center between January 2004 and December 2015 for suspected non-neoplastic neurological disease was performed. The clinical presentation, imaging, and laboratory results were collected and compared between diagnostic groups. RESULTS: Sixty-eight percent of the biopsies led to a definitive diagnosis. The most common histological diagnosis was central nervous system lymphoma (eight cases), followed by astrocytoma, demyelinating disease, and progressive multifocal leukoencephalopathy (four cases each). No clinical characteristics were found to predict a diagnostic biopsy or to correlate with a specific diagnosis. Importantly, a distinct diagnosis from the initially suspected was achieved in 52% of cases and biopsy findings led to a change of therapeutic orientation in 78% of the cases. CONCLUSIONS: Our results suggest that brain biopsies have a significant impact on patient management and should be considered early in selected cases in which less invasive testing was unable to reach a definitive diagnosis.

CNS involvement in V30M transthyretin amyloidosis: clinical, neuropathological and biochemical findings.

OBJECTIVES: Since liver transplant (LT) was introduced to treat patients with familial amyloid polyneuropathy carrying the V30M mutation (ATTR-V30M), ocular and cardiac complications have developed. Long-term central nervous system (CNS) involvement was not investigated. Our goals were to: (1) identify and characterise focal neurological episodes (FNEs) due to CNS dysfunction in ATTR-V30M patients; (2) characterise neuropathological features and temporal profile of CNS transthyretin amyloidosis. METHODS: We monitored the presence and type of FNEs in 87 consecutive ATTR-V30M and 35 non-ATTR LT patients. FNEs were investigated with CT scan, EEG and extensive neurovascular workup. MRI studies were not performed because all patients had cardiac pacemakers as part of the LT protocol. We characterised transthyretin amyloid deposition in the brains of seven ATTR-V30M patients, dead 3-13 years after polyneuropathy onset. RESULTS: FNEs occurred in 31% (27/87) of ATTR-V30M and in 5.7% (2/35) of the non-ATTR transplanted patients (OR=7.0, 95% CI 1.5 to 33.5). FNEs occurred on average 14.6 years after disease onset (95% CI 13.3 to 16.0) in ATTR-V30M patients, which is beyond the life expectancy of non-transplanted ATTR-V30M patients (10.9, 95% CI 10.5 to 11.3). ATTR-V30M patients with FNEs had longer disease duration (OR=1.24; 95% CI 1.07 to 1.43), renal dysfunction (OR=4.65; 95% CI 1.20 to 18.05) and were men (OR=3.57; 95% CI 1.02 to 12.30). CNS transthyretin amyloidosis was already present 3 years after polyneuropathy onset and progressed from the meninges and its vessels towards meningocortical vessels and the superficial brain parenchyma, as disease duration increased. CONCLUSIONS: Our findings indicate that CNS clinical involvement occurs in ATTR-V30M patients regardless of LT. Longer disease duration after LT can provide the necessary time for transthyretin amyloidosis to progress until it becomes clinically relevant. Highly sensitive imaging methods are needed to identify and monitor brain ATTR. Disease modifying therapies should consider brain TTR as a target.

Novel TTC19 mutation in a family with severe psychiatric manifestations and complex III deficiency.

Complex III of the mitochondrial respiratory chain (CIII) catalyzes transfer of electrons from reduced coenzyme Q to cytochrome c. Low biochemical activity of CIII is not a frequent etiology in disorders of oxidative metabolism and is genetically heterogeneous. Recently, mutations in the human tetratricopeptide 19 gene (TTC19) have been involved in the etiology of CIII deficiency through impaired assembly of the holocomplex. We investigated a consanguineous Portuguese family where four siblings had reduced enzymatic activity of CIII in muscle and harbored a novel homozygous mutation in TTC19. The clinical phenotype in the four sibs was consistent with severe olivo-ponto-cerebellar atrophy, although their age at onset differed slightly. Interestingly, three patients also presented progressive psychosis. The mutation resulted in almost complete absence of TTC19 protein, defective assembly of CIII in muscle, and enhanced production of reactive oxygen species in cultured skin fibroblasts. Our findings add to the array of mutations in TTC19, corroborate the notion of genotype/phenotype variability in mitochondrial encephalomyopathies even within a single family, and indicate that psychiatric manifestations are a further presentation of low CIII.

Peripheral neuropathy in systemic vasculitis and other autoimmune diseases - a report of five cases emphasizing the importance of etiologic characterization.

INTRODUCTION: Peripheral neuropathies may present in the context of systemic vasculitis and other autoimmune diseases. The etiologic characterization is crucial to define the treatment and prognosis in secondary vasculitis. The purpose of this study is to describe the pathway of etiologic investigation including the role of nerve biopsy. METHODS: Retrospective analysis of patients seen in the neuromuscular outpatient clinic during the last four years with peripheral neuropathy in the context of systemic vasculitis or other autoimmune diseases. RESULTS: We present five patients with stepwise progressive sensorimotor deficits of upper and lower limbs. All patients presented with systemic features and one of them had an established diagnosis of systemic vasculitis. They underwent an extended blood panel, including autoimmune and serologic tests. Electromyography and nerve conduction studies revealed asymmetric axonal sensorimotor polyneuropathies in four patients, and an axonal sensorimotor multiple mononeuropathy in one. Four patients underwent nerve biopsy and the other performed a skin biopsy, with findings suggestive of possible vasculitic processes. The etiologies identified included microscopic polyangiitis, HBV-related polyarteritis nodosa and two eosinophilic granulomatosis with polyangiitis. In the last patient a specific etiology could not be established. CONCLUSION: This series reveals the etiologic and phenotypic diversity of peripheral neuropathies related with systemic vasculitis. The therapeutic approach and prognosis were distinct in each patient, emphasizing the importance of a prompt diagnosis and appropriate treatment.

A novel molecular link between HOXA9 and WNT6 in glioblastoma identifies a subgroup of patients with particular poor prognosis.

Despite much effort to improve treatments, patients with malignant glioma still present a very poor prognosis that has not changed significantly in the last decades. In this context, it is crucial to better understand glioma pathogenesis to identify new molecular prognostic subgroups and therapeutic targets. WNT6 was recently identified as a new oncogenic molecule in glioblastoma (GBM), with prognostic value in patients, but the mechanisms underlying WNT6 aberrant expression in glioma are still unknown. WNT6 was overexpressed in a subset of gliomas independently of IDH mutations, 1p/19q codeletion status, and WNT6 gene copy number. Interestingly, WNT6 expression is associated with the DNA methylation levels of particular CpG regions at both the WNT6 promoter and the gene body in glioma patient samples. HOXA9, a transcription factor previously associated with poorer clinical outcome in GBM, was identified as a novel transcriptional regulator of WNT6, activating the WNT/ß-catenin pathway in vitro and in vivo. In various cohorts of glioma patients, mRNA levels of WNT6 and HOXA9 were significantly correlated, extending our in vitro and in vivo findings into the clinical setting. Interestingly, this novel molecular link between WNT6 and HOXA9 was not limited to glioma, as they were co-expressed also in patients with other tumor types. Clinically, WNT6 was a prognostic biomarker of shorter survival in GBM, independently of HOXA9 expression. Concomitant high expression of both WNT6 and HOXA9 identified a subgroup of patients with particularly dismal survival. These findings describe novel WNT6 regulatory mechanisms in GBM, establishing particular DNA methylation patterns and HOXA9 as critical regulators of WNT6 expression in glioma. This HOXA9-WNT6 molecular link supports WNT signaling in GBM cells and is a powerful prognostic biomarker, highlighting the clinical relevance of this axis in patients. Novel therapies targeting WNT6-HOXA9 signaling may thus be useful for this deadly disease.

Loss of SPINT2 expression frequently occurs in glioma, leading to increased growth and invasion via MMP2.

PURPOSE: High-grade gliomas (HGG) remain one of the most aggressive tumors, which is primarily due to its diffuse infiltrative nature. Serine proteases and metalloproteases are known to play key roles in cellular migration and invasion mechanisms. SPINT2, also known as HAI-2, is an important serine protease inhibitor that can affect MET signaling. SPINT2 has been found to be frequently downregulated in various tumors, whereby hypermethylation of its promoter appears to serve as a common mechanism. Here, we assessed the clinical relevance of SPINT2 expression and promoter hypermethylation in pediatric and adult HGG and explored its functional role. METHODS: A series of 371 adult and 77 pediatric primary HGG samples was assessed for SPINT2 protein expression (immunohistochemistry) and promoter methylation (methylation-specific PCR) patterns. After SPINT2 knockdown and knock-in in adult and pediatric HGG cell lines, a variety of in vitro assays was carried out to determine the role of SPINT2 in glioma cell viability and invasion, as well as their mechanistic associations with metalloprotease activities. RESULTS: We found that SPINT2 protein expression was frequently absent in adult (85.3%) and pediatric (100%) HGG samples. The SPINT2 gene promoter was found to be hypermethylated in approximately half of both adult and pediatric gliomas. Through functional assays we revealed a suppressor activity of SPINT2 in glioma cell proliferation and viability, as well as in their migration and invasion. These functions appear to be mediated in part by MMP2 expression and activity. CONCLUSIONS: We conclude that dysregulation of SPINT2 is a common event in both pediatric and adult HGG, in which SPINT2 may act as a tumor suppressor.

WNT6 is a novel oncogenic prognostic biomarker in human glioblastoma.

Glioblastoma (GBM) is a universally fatal brain cancer, for which novel therapies targeting specific underlying oncogenic events are urgently needed. While the WNT pathway has been shown to be frequently activated in GBM, constituting a potential therapeutic target, the relevance of WNT6, an activator of this pathway, remains unknown. Methods: WNT6 protein and mRNA levels were evaluated in GBM. WNT6 levels were silenced or overexpressed in GBM cells to assess functional effects in vitro and in vivo. Phospho-kinase arrays and TCF/LEF reporter assays were used to identify WNT6-signaling pathways, and significant associations with stem cell features and cancer-related pathways were validated in patients. Survival analyses were performed with Cox regression and Log-rank tests. Meta-analyses were used to calculate the estimated pooled effect. Results: We show that WNT6 is significantly overexpressed in GBMs, as compared to lower-grade gliomas and normal brain, at mRNA and protein levels. Functionally, WNT6 increases typical oncogenic activities in GBM cells, including viability, proliferation, glioma stem cell capacity, invasion, migration, and resistance to temozolomide chemotherapy. Concordantly, in in vivo orthotopic GBM mice models, using both overexpressing and silencing models, WNT6 expression was associated with shorter overall survival, and increased features of tumor aggressiveness. Mechanistically, WNT6 contributes to activate typical oncogenic pathways, including Src and STAT, which intertwined with the WNT pathway may be critical effectors of WNT6-associated aggressiveness in GBM. Clinically, we establish WNT6 as an independent prognostic biomarker of shorter survival in GBM patients from several independent cohorts. Conclusion: Our findings establish WNT6 as a novel oncogene in GBM, opening opportunities to develop more rational therapies to treat this highly aggressive tumor.

Vascular Pathology Causing Late Onset Generalized Chorea: A Clinico-Pathological Case Report.

BACKGROUND: Chorea may occur as a manifestation of an acute stroke. Patients with vascular-related chorea typically present with an acute or subacute onset of hemichorea, contralateral to the lesion. METHODS AND FINDINGS: In this clinico-pathological case, we report a 90-year-old female who presented, at age 81, with a transient episode of generalized chorea. Over the years, the patient continued to have intermittent episodes of generalized chorea or hemichorea, followed by a progressive dementia syndrome with gait and sphincter disturbance. There was no family history of chorea or dementia. Laboratory tests for paraneoplastic or autoimmune disorders and genetic testing for Huntington's disease were normal or negative. Magnetic resonance imaging showed subcortical and basal ganglia atrophy associated with ischemic leukoencephalopathy and lacunar infarcts. The post-mortem examination identified multiple lacunar infarcts (cortex, white matter, thalamus, basal ganglia) and minor Alzheimer's disease neuropathological changes. CONCLUSIONS: Vascular disease, affecting the basal ganglia, is included in most lists of causes of generalized chorea. Proven cases are difficult to find. We present a rare case of vascular pathology causing late onset generalized and intermittent chorea. We highlight the intermittent nature of the chorea that could be explained by cumulative vascular lesions or functional disconnection in a previous deficient circuit.

Inflammatory myopathy associated with myasthenia gravis with and without thymic pathology: Report of four cases and literature review.

INTRODUCTION: The association of myasthenia gravis (MG) and inflammatory myopathy is rare and often only one of the diseases is diagnosed. Thymus pathology may be in the origin of such disease association. METHODS: We described four patients with both MG and inflammatory myopathy. RESULTS: These cases correspond to 2.3% of our MG cohort. Case 1: MG, polymyositis and thymolipoma; case 2: MG and necrotizing myopathy without thymic pathology on a background of scleroderma, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, telangiectasia (CREST); case 3: MG and dermatomyositis without thymic pathology; case 4: MG and dermatomyositis with type C thymoma. DISCUSSION: The recognition of these neuromuscular co-morbidities contributes to (i) understanding their pathogenic mechanisms, (ii) developing better management approaches and (iii) further improving disease outcomes.

Hansen Neuropathy: Still a Possible Diagnosis in the Investigation of a Peripheral Neuropathy.

INTRODUCTION: Leprosy is still one of the most frequent causes of peripheral neuropathy. Although regarded as eradicated in Portugal, is still documented in neuropathological study of patients with clinical peripheral neuropathy without proper diagnosis. MATERIAL AND METHODS: Review of the cases of Hansen disease neuropathy diagnosed in Neuropathology Unit of Centro Hospitalar do Porto between 1978 and 2013, atending to gender, age, clinical manifestations and neuropathological findings. RESULTS: Twenty one patients were identified with neuropathological diagnosis of Hansenâs disease neuropathy, predominantly male. The mean age at diagnosis was 52 years, and sensory symptoms predominate as neurological manifestation of disease. Interval between symptoms and diagnosis was 1-38 years. In most nerve samples tuberculoid type of disease was identified. Bacilli were detected in skin and nerve in 44% of cases. DISCUSSION: Mononeuritis is the most common presentation of leprosy but other clinical manifestations are possible, including skin lesions. Infection with M. leprae injures myelinated and unmyelinated fibres, with replacement of nerve tissue by collagen fibrosis. The diagnosis of leprosy is only achieved by neuropathological study of skin lesions and / or peripheral nerve, supported by the identification of the bacillus. CONCLUSION: Hansen disease remains a public health problem in tropical areas and, although rare, still described in Western countries reason why should still be considered as a diagnostic possibility in the investigation of peripheral neuropathy.

Introdução: A lepra continua a ser uma das causas mais frequentes de neuropatia periférica. Apesar de tida como erradicada em Portugal, ainda se documenta no estudo neuropatológico de doentes com clínica de neuropatia periférica sem diagnóstico etiológico definido.Material e Métodos: Revisão dos casos neuropatia por doença de Hansen diagnosticados na Unidade de Neuropatologia do Centro Hospitalar do Porto no período de 1978 e 2013 atendendo ao género, idade, manifestações clínicas e achados neuropatológicos.Resultados: Foram identificados 21 doentes com diagnóstico neuropatológico de neuropatia por doença de Hansen, com predomínio do sexo masculino. A idade média ao diagnóstico foi de 52 anos, sendo a sintomatologia sensitiva predominante. O intervalo entre sintomatologia e diagnóstico oscilou entre 1 a 38 anos. Na maioria foi identificada forma tuberculoide em biópsia de nervo e detetados bacilos em pele e nervo em 44% dos casos.Discussão: A mononeurite é a forma mais comum de apresentação de hanseníase, podendo cursar com outras manifestações clínicas incluindo lesões cutâneas. A infeção pelo M. leprae lesiona fibras mielinizadas e não mielinizadas, com substituição do tecido nervoso por colagénio resultando em fibrose. O diagnóstico da lepra é apenas conseguido por estudo neuropatológico das lesões cutâneas e/ou nervo periférico, adjuvado pela identificação do bacilo.Conclusão: A doença de Hansen continua a ser um problema de saúde pública em áreas tropicais e, apesar de rara, ainda descrita em países ocidentais, devendo ser considerada como uma hipótese de diagnóstico na investigação de neuropatia periférica.

[A retrospective study of Creutzfeldt-Jakob disease in North of Portugal 1993-2002: demographic, clinical and neuropathological features]. / Estudo retrospectivo da doença de Creutzfeldt-Jakob diagnosticada no norte de Portugal entre 1993-2002: características demográficas, clínicas e neuropatológicas.

OBJECTIVE: Description of the demographic, clinical and neuropathological features of 11 cases of Creutzfeldt-Jakob disease (CJD). METHOD: Review of the clinical and neuropathological features of patients with CJD diagnosed in hospitals in the North of Portugal between 1993 and 2002. RESULTS: Eleven patients were identified, 4 females: mean age of onset of symptoms--64 years, mean duration of disease--8 months. All presented with a syndrome of progressive dementia with myoclonus, with four patients presenting with cerebellar signs. Neuropathological examination of brain at autopsy showed spongiosis and reactive gliosis associated with neuronal loss. In eight cases immunocytochemistry for prion protein (PrP) was carried out and was positive. CONCLUSION: The group of patients described represents the heterogeneity of the clinical phenotypes possible in CJD. Neuropathological examination is still indispensable to make the definitive diagnosis of the disease.

Expanding the MTM1 mutational spectrum: novel variants including the first multi-exonic duplication and development of a locus-specific database.

Myotubular myopathy (MIM#310400), the X-linked form of Centronuclear myopathy (CNM) is mainly characterized by neonatal hypotonia and inability to maintain unassisted respiration. The MTM1 gene, responsible for this disease, encodes myotubularin - a lipidic phosphatase involved in vesicle trafficking regulation and maturation. Recently, it was shown that myotubularin interacts with desmin, being a major regulator of intermediate filaments. We report the development of a locus-specific database for MTM1 using the Leiden Open Variation database software (http://www.lovd.nl/MTM1), with data collated for 474 mutations identified in 472 patients (by June 2012). Among the entries are a total of 25 new mutations, including a large deletion encompassing introns 2-15. During database implementation it was noticed that no large duplications had been reported. We tested a group of eight uncharacterized CNM patients for this specific type of mutation, by multiple ligation-dependent probe amplification (MLPA) analysis. A large duplication spanning exons 1-5 was identified in a boy with a mild phenotype, with results pointing toward possible somatic mosaicism. Further characterization revealed that this duplication causes an in-frame deletion at the mRNA level (r.343_444del). Results obtained with a next generation sequencing approach suggested that the duplication extends into the neighboring MAMLD1 gene and subsequent cDNA analysis detected the presence of a MTM1/MAMLD1 fusion transcript. A complex rearrangement involving the duplication of exon 10 has since been reported, with detection also enabled by MLPA analysis. It is thus conceivable that large duplications in MTM1 may account for a number of CNM cases that have remained genetically unresolved.

Impact of EGFR genetic variants on glioma risk and patient outcome.

BACKGROUND: The epidermal growth factor receptor (EGFR) regulates important cellular processes and is frequently implicated in human tumors. Three EGFR polymorphisms have been described as having a transcriptional regulatory function: two single-nucleotide polymorphisms in the essential promoter region, -216G/T and -191C/A, and a polymorphic (CA)(n) microsatellite sequence in intron 1. We aimed to elucidate the roles of these EGFR polymorphisms in glioma susceptibility and prognosis. METHODS: We conducted a case-control study with 196 patients with glioma and 168 cancer-free controls. Unconditional multivariate logistic regression models were used to calculate ORs and 95% confidence intervals. A Cox regression model was used to evaluate associations with patient survival. False-positive report probabilities were also assessed. RESULTS: None of the EGFR -216G/T variants was significantly associated with glioma risk. The -191C/A genotype was associated with higher risk for glioma when the (CA)(n) alleles were classified as short for ≤16 or ≤17 repeats. Independently of the (CA)(n) repeat cutoff point used, shorter (CA)(n) repeat variants were significantly associated with increased risk for glioma, particularly glioblastoma and oligodendroglioma. In all tested models with different (CA)(n) cutoff points, only -191C/A genotype was consistently associated with improved survival of patients with glioblastoma. CONCLUSIONS: Our findings implicate EGFR -191C/A and the (CA)(n) repeat polymorphisms as risk factors for gliomas, and suggest -191C/A as a prognostic marker in glioblastoma. IMPACT: Our data support a role of these EGFR polymorphisms in determining glioma susceptibility, with potential relevance for molecularly based stratification of patients with glioblastoma for individualized therapies.

Chondroma of the Cerebral Falx: Case Report of a Very Rare Intracranial Tumor / Condroma da foice do cérebro: relato de caso de um tumor intracraniano muito raro

Chondromas are a benign cartilaginous tumor that account for approximately 0.5% of primary intracranial tumors. They usually arise from the synchondrosis of the skull base, being rarely reported elsewhere (dura convexity, falx, or even intraparenchymal). Because they are very rare tumors sharing clinical behavior and imagiological similarities with the much more common meningioma, the clinical diagnosis is frequently mistaken after an initial imaging workup. The authors present a case of a 48-year-old woman, with frequent headaches and an extra-axial tumor arising from the anterior falx, initially diagnosed as a meningioma.

Condromas são tumores cartilaginosos benignos que correspondem por aproximadamente 0,5% dos tumores primários intracranianos. Eles geralmente surgem da sincondrose da base do crânio, sendo raramente registrados em outros locais como a convexidade dural, a foice, até mesmo no parênquima cerebral. Por serem tumores muito raros que compartilham comportamento clínico e imagiológico com meningiomas, o diagnóstico é frequentemente confundido após exame de imagem inicial. Os autores apresentam o caso de uma mulher de 48 anos, com cefaleia frequente e um tumor extra-axial ascendendo da foice anterior, inicialmente diagnosticado como um meningioma.

Benign osteoblastoma of the sphenoid bone.

Osteoblastoma is an uncommon benign bone tumor that accounts for 1% of all primary bone tumors. Well documented in the spine and long bones, it is rarely found in the skull, namely in the sphenoid bone, with only five cases reported in the literature. We report a case of an 11-year-old girl with a histologically confirmed benign osteoblastoma in an unusual location and an atypical aspect on the imaging studies.

Estudo retrospectivo da doença de Creutzfeldt-Jakob diagnosticada no norte de Portugal entre 1993-2002: características demográficas, clínicas e neuropatológicas / A retrospective study of Creutzfeldt-Jakob disease in North of Portugal 1993-2002: demographic, clinical and neuropathological features

INTRODUÇÃO E OBJETIVO: Descrição das características demográficas, clinicas e neuropatológicas de 11 doentes com doença de Creutzfeldt-Jakob (DCJ). MÉTODO: Revisão clínica e neuropatológica de doentes com DCJ diagnosticados entre 1993 e 2002 em hospitais do Norte de Portugal. RESULTADOS: Foram identificados 11 doentes (4 do sexo feminino; idade média de início dos sintomas, 64 anos; média de duração da doença, 8 meses). Todos apresentaram síndrome demencial progressiva associada a mioclonias, sendo a síndrome cerebelar a forma de apresentação inicial em quatro deles. O estudo neuropatológico revelou sempre espongiose e gliose reativa associada a perda neuronal. O estudo imunocitoquímico para proteína priônica (PrP) foi positivo nos oito casos em que foi executado. CONCLUSÃO: O grupo de doentes descritos constitui uma série clinica representativa da heterogeneidade de fenótipos possíveis da DCJ esporádica. O estudo neuropatológico é ainda indispensável para o diagnóstico definitivo da doença