Neurodengue, a narrative review of the literature.

Dengue fever (DF) is the most frequent arboviral disease globally. Deforestation, armed conflicts, and climate change have caused an unprecedented global spread of DF, raising concerns in healthcare systems worldwide. Systemic manifestations of the disease range from mild to severe and, in some cases, can lead to death. Although neurological complications have been reported over the last few decades, they are often neglected or underreported. The present narrative review aims to describe the most important central and peripheral nervous system complications and provide guidance to neurologists in terms of diagnosis and management.

A dengue é a arbovirose mais frequente no mundo. O desmatamento, os conflitos armados e as mudanças climáticas levaram a uma disseminação global e sem precedentes da dengue, o que gera preocupações na maioria dos sistemas de saúde em todo o mundo. As manifestações sistêmicas variam de leves a graves, incluindo morte. Complicações neurológicas têm sido descritas nas últimas décadas, mas geralmente são negligenciadas ou subnotificadas. O objetivo desta revisão narrativa é descrever as complicações neurológicas centrais e periféricas e auxiliar os neurologistas em seu diagnóstico e manejo.

Lessons from the Cerebrospinal Fluid Analysis of HTLV-1-Infected Individuals: Biomarkers of Inflammation for HAM/TSP Development.

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a neurodegenerative disease that leads to motor impairment due to a chronic inflammatory process in the central nervous system (CNS). However, the HAM/TSP pathogenesis is not completely clear, and biomarkers to define the disease prognosis are still necessary. Thus, we aimed to identify biomarkers for HAM/TSP and potential mechanisms involved in disease development. To that end, the concentrations of VILIP-1, BDNF, VEGF, ß-NGF, TGF-ß1, fractalkine/CX3CL1, IL-6, IL-18, and TNF-α, and the soluble forms of TREM-1, TREM-2, and RAGE, were assessed using a multiplex bead-based immunoassay in paired cerebrospinal fluid (CSF) and serum samples from HAM/TSP patients (n = 20), asymptomatic HTLV-1 carriers (AC) (n = 13), and HTLV-1-seronegative individuals (n = 9), with the results analyzed according to the speed of HAM/TSP progression. HAM/TSP patients had elevated fractalkine in the serum but not in the CSF, particularly those with low neuroinflammatory activity (CSF/serum ratio of neopterin <1 and of CXCL10 < 2). HAM/TSP patients with normal CSF levels of neurofilament light chain (NfL) showed elevated ß-NGF in serum, and serum BDNF levels were increased in HTLV-1-infected individuals, particularly in HTLV-1 AC. Both HTLV-1 AC and HAM/TSP patients had lower TGF-ß1 levels in CSF compared to uninfected individuals, and HAM/TSP patients with active CNS inflammation showed higher CSF levels of IL-18, which correlated with markers of inflammation, neuronal death, and blood−brain-barrier permeability. Although none of the factors evaluated were associated with the speed of HAM/TSP progression, reduced TGF-ß1 levels in CSF suggest that suppressive responses to control subclinical and/or active neurodegeneration are impaired, while increased CSF IL-18 indicates the involvement of inflammasome-mediated mechanisms in HAM/TSP development.

Chitotriosidase 1 in the cerebrospinal fluid as a putative biomarker for HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) progression.

Human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is an inflammatory neurodegenerative disease that affects motor, urinary, intestinal, and sensory functions. Typically, HAM/TSP is slowly progressive, but it may vary from limited motor disability after decades (very slow progression) to loss of motor function in a few years from disease onset (rapid). In this study, we aimed to identify prognostic biomarkers for HAM/TSP to support patient management. Thus, proteomic analysis of the cerebrospinal fluid (CSF) was performed with samples from HTLV-1 asymptomatic carriers (AC) (n=13) and HAM/TSP patients (n=21) with rapid, typical, and very slow progression using quantitative label-free liquid chromatography/tandem mass spectrometry. Enrichment analyses were also carried out to identify key biological processes associated with distinct neurological conditions in HTLV-1 infection. Candidate biomarkers were validated by ELISA in paired CSF and serum samples, and samples from HTLV-1-seronegative individuals (n=9) were used as controls. CSF analysis identified 602 proteins. Leukocyte/cell activation, immune response processes and neurodegeneration pathways were enriched in rapid progressors. Conversely, HTLV-1 AC and HAM/TSP patients with typical and very slow progression had enriched processes for nervous system development. Differential expression analysis showed that soluble vascular cell adhesion molecule 1 (sVCAM-1), chitotriosidase 1 (CHIT1), and cathepsin C (CTSC) were upregulated in HAM/TSP. However, only CHIT1 was significantly elevated after validation, particularly in HAM/TSP rapid progressors. In contrast, none of these biomarkers were altered in serum. Additionally, CSF CHIT1 levels in HAM/TSP patients positively correlated with the speed of HAM/TSP progression, defined as points in the IPEC-2 HAM/TSP disability scale per year of disease, and with CSF levels of phosphorylated neurofilament heavy chain, neopterin, CXCL5, CXCL10, and CXCL11. In conclusion, higher CSF levels of CHIT1 were associated with HAM/TSP rapid progression and correlated with other biomarkers of neuroinflammation and neurodegeneration. Therefore, we propose CHIT1 as an additional or alternative CSF biomarker to identify HAM/TSP patients with a worse prognosis.

Olfactory nerve: from ugly duckling to swan.

BACKGROUND: The olfactory nerve has never been the shining star of neurological examination. Quite the contrary, examining the first cranial nerve is often an overlooked step. As cases of anosmia secondary to COVID-19 infection continue to rise, the 2020 pandemic has shed new light on this much-forgotten nerve, its value as an aid to diagnosis of several diseases and its central role in our daily lives. OBJECTIVE: We aimed to emphasize how essential and simple clinical examination of the olfactory system can be by highlighting practical techniques and clinical tips for its assessment. We also share pearls and pitfalls in localization and differential diagnosis, which may prove valuable to busy clinicians. METHODS: A broad review of the literature was conducted by searching PubMed, Cochrane and Google Scholar for articles and books containing topics regarding examination of the olfactory nerve and its anatomy, physiology and pathology. No particular inclusion or exclusion criteria were used. RESULTS: Forty different works were found, between books and articles, from which 20 were selected after careful analysis. CONCLUSIONS: Despite the tragedy and adversity that followed the COVID-19 pandemic, its legacy has taught us a crystal-clear lesson: olfaction should no longer be neglected in clinical practice.

Olfactory nerve: from ugly duckling to swan / Nervo olfatório: de patinho feio a cisne

ABSTRACT Background: The olfactory nerve has never been the shining star of neurological examination. Quite the contrary, examining the first cranial nerve is often an overlooked step. As cases of anosmia secondary to COVID-19 infection continue to rise, the 2020 pandemic has shed new light on this much-forgotten nerve, its value as an aid to diagnosis of several diseases and its central role in our daily lives. Objective: We aimed to emphasize how essential and simple clinical examination of the olfactory system can be by highlighting practical techniques and clinical tips for its assessment. We also share pearls and pitfalls in localization and differential diagnosis, which may prove valuable to busy clinicians. Methods: A broad review of the literature was conducted by searching PubMed, Cochrane and Google Scholar for articles and books containing topics regarding examination of the olfactory nerve and its anatomy, physiology and pathology. No particular inclusion or exclusion criteria were used. Results: Forty different works were found, between books and articles, from which 20 were selected after careful analysis. Conclusions: Despite the tragedy and adversity that followed the COVID-19 pandemic, its legacy has taught us a crystal-clear lesson: olfaction should no longer be neglected in clinical practice.

RESUMO Antecedentes: O nervo olfatório nunca foi a estrela do exame neurológico. Pelo contrário, o exame desse nervo craniano é um passo frequentemente ignorado. No entanto, o aumento exponencial de casos de anosmia secundária a COVID-19 o colocou sob os holofotes, tanto em relação á sua função para o ser humano em sociedade, como seu papel no auxílio do diagnóstico de diversas patologias. Objetivos: Enfatizar quão importante é examinar o nervo olfatório e compreender as desordens do seu sistema. Ressaltamos pérolas clínicas e erros comuns no exame deste nervo, além dicas que possam auxiliar no diagnóstico de uma série de doenças neurológicas e sistêmicas. Métodos: Uma ampla revisão da literatura foi conduzida por meio de busca no PubMed, Cochrane e Google Acadêmico por artigos e livros relacionados aos tópicos do exame físico, fisiologia, anatomia e patologia do nervo olfatório. Não foram utilizados critérios específicos de inclusão ou exclusão. Resultados: Foram encontrados 40 artigos itens relacionados na língua inglesa, dentre os quais livros e artigos, tendo sido analisados e selecionados um a um até o total de 20 referências. Conclusões: Apesar da tragédia e adversidade trazidas pela pandemia de COVID-19, uma lição clara permanece: o olfato não deve mais ser negligenciado na prática clínica.

Polymorphisms in HTLV-1 Tax-responsive elements in HTLV-1-associated myelopathy/tropical spastic paraparesis patients are associated with reduced proviral load but not with disease progression.

Human T-lymphotropic virus type 1 (HTLV-1) provirus expression is mainly directed by Tax-responsive elements (TRE) within the long terminal repeats (LTR). Mutations in TRE can reduce provirus expression and since a high proviral load (PVL) is a risk factor for the development of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), we evaluated polymorphisms in the 5' LTR and the association with PVL and disease progression. HTLV-1 LTR and tax sequences derived from asymptomatic carriers (AC) and HAM/TSP patients followed in a longitudinal study were analysed according to PVL and clinical severity. Individuals infected with HTLV-1 presenting the canonical TRE, considering strain ATK-1 as the consensus, displayed sustained higher PVL. By contrast, an LTR A125G mutation in TRE was associated with slightly reduced PVL only in HAM/TSP patients, although it did not influence the speed of disease progression. Moreover, this polymorphism was frequent in Latin American strains of the HTLV-1 Cosmopolitan Transcontinental subtype. Therefore, polymorphisms in the 5' TRE of HTLV-1 may represent one of the factors influencing PVL in HAM/TSP patients, especially in the Latin American population. Indeed, higher PVL in the peripheral blood has been associated with an increased inflammatory activity in the spinal cord and to a poorer prognosis in HAM/TSP. However, this event was not associated with TRE polymorphisms.

Cerebrospinal fluid findings in neurological diseases associated with COVID-19 and insights into mechanisms of disease development.

OBJECTIVES: To analyze the cerebrospinal fluid (CSF) of patients with SARS-CoV-2 infection and neurological manifestations to provide evidence for the understanding of mechanisms associated with central nervous system (CNS) involvement in COVID-19. METHODS: Patients (n = 58) were grouped according to their main neurological presentation: headache (n = 14); encephalopathy (n = 24); inflammatory neurological diseases, including meningoencephalitis (n = 4), acute myelitis (n = 3), meningitis (n = 2), acute disseminated encephalomyelitis (ADEM) (n = 2), encephalitis (n = 2), and neuromyelitis optica (n = 1); and Guillain-Barré syndrome (n = 6). Data regarding age, sex, cerebrovascular disease, and intracranial pressure were evaluated in combination with CSF profiles defined by cell counts, total protein and glucose levels, concentration of total Tau and neurofilament light chain (NfL) proteins, oligoclonal band patterns, and detection of SARS-CoV-2 RNA. RESULTS: CSF of patients with inflammatory neurological diseases was characterized by pleocytosis and elevated total protein and NfL levels. Patients with encephalopathy were mostly older men (mean age of 61.0 ± 17.6 years) with evidence of cerebrovascular disease. SARS-CoV-2 RNA in CSF was detected in 2 of 58 cases: a patient with refractory headache, and another patient who developed ADEM four days after onset of COVID-19 symptoms. Three patients presented intrathecal IgG synthesis, and four had identical oligoclonal bands in CSF and serum, indicating systemic inflammation. CONCLUSION: Patients with neurological manifestations associated with COVID-19 had diverse CSF profiles, even within the same clinical condition. Our findings indicate a possible contribution of viral replication on triggering CNS infiltration by immune cells and the subsequent inflammation promoting neuronal injury.

Patients with COVID-19 and neurological manifestations show undetectable SARS-CoV-2 RNA levels in the cerebrospinal fluid.

We report that patients with COVID-19 displaying distinct neurological disorders have undetectable or extremely low levels of SARS-CoV-2 RNA in the cerebrospinal fluid, indicating that viral clearance precede the neurological involvement. This finding points to the need for the development of more sensitive molecular tests and the investigation of other neurotropic pathogens to exclude concurrent neuroinfection.

Lack of association between single-nucleotide polymorphisms of pro- and anti-inflammatory cytokines and HTLV-1-associated myelopathy / tropical spastic paraparesis development in patients from Rio de Janeiro, Brazil.

BACKGROUND: HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a progressive neurological and inflammatory disease, associated with HTLV-1 infection. HAM/TSP neurological disease is a consequence of an inflammatory reaction, and adaptive immune responses, through the secretion of anti-inflammatory and pro-inflammatory cytokines, play an important role in the outcome of infection and disease progression. Studies addressing the association between cytokines functional single nucleotide polymorphisms and HAM/TSP development are scarce. METHODS: The genetic polymorphisms of cytokine genes were evaluated in HAM/TSP patients (n = 68) and in asymptomatic HTLV-1 positive carriers (n = 83) from Rio de Janeiro, Brazil, in a case-control study. HTLV-1 infected patients were genotyped for SNPs in five cytokine genes: TNFA-308G/A, IL6-174G/C, IFNG + 874 T/A, TGFB at the codons + 10 T/C and + 25G/C, IL10-592C/A and -819C/T, and -1082A/G and proviral load (PVL) was quantified. Associations between genotypes, haplotypes, clinical outcome and pro viral load were evaluated. RESULTS: Lack of association between the cytokine polymorphisms and disease outcome was observed. The genotypes TNFA-308GG, IL6-174GG/GC, IL10-592AA and -819CC and TGFb1 high producers phenotypes were correlated with higher PVL in HAM/TSP patients versus asymptomatic carriers. CONCLUSIONS: We did not observe association between cytokine polymorphisms and risk for HAM/TSP development in Brazilian HTLV-1 infected individuals, regardless of differences in PVL between HAM/TSP versus asymptomatic carriers in specific cytokine polymorphisms.

Identificação de broncoaspiração por disfagia orofaríngea em pacientes com pneumonia comunitária / Identification of bronchoaspiration due to oropharyngeal dysphagia in patients with community pneumonia

A pneumonia é uma inflamação do parênquima pulmonar resultante do processo infeccioso ou inflamatório, responsável por 5% do total das mortes notificadas no mundo, instalando-se geralmente em indivíduos cujos mecanismos de defesa encontram-se comprometidos. A relação estreita entre as alterações da deglutição e a predisposição para pneumonias bacterianas de repetição e sua associação com desordens neuromusculares tem sido objeto constante de pesquisas. Objetivo: propor um protocolo clínico para detecção de broncoaspiração entre pacientes com pneumonia sem realização de videofluoroscopia. Metodologia: 70 pacientes com média de idade de 67,5+16,3 anos, foram submetidos a 2 protocolos de avaliação da deglutição validados na literatura: Tohara (2003) e Xerez (2002). Resultados: Foram considerados aspiradores pelo exame clínico 62,9% (44/70). Ser classificado aspirador pelo exame clínico mostrou correlação estatística significativa com a presença de doença neurológica e redução do estado de alerta (p<0,001). Conclusão: o exame clínico foi capaz de detectar os pacientes em risco para pneumonia aspirativa. A presença da associação de fatores deve levar a equipe a adotar cautela maior no manuseio da alimentação do paciente com pneumonia que pode ser de origem aspirativa.

Pneumonia is a pulmonary parenchyma inflammation that results from an infectious or inflammatory process, responsible for 5% of all deaths reported in the world; it usually affects individuals whose defense mechanisms are compromised. The close association between swallowing abnormalities and the predisposition to repetitive bacterial pneumonia and its association with neuromuscular disorders have been the aim of many studies. Aim: To propose a clinical protocol to detect bronchoaspiration in patients with pneumonia, without videofluoroscopy. Method: 70 patients with mean age of 67.5±16.3 years were submitted to two swallowing evaluation protocols, previously validated in literature: (Tohara (2003) and Xerez (2002)).Results: 62.9% (44/70) of the patients were considered aspirators by the clinical examination, which showed a significant statistical correlation with the presence of neurological disorders and reduction in the state of alertness (p <0.001). Conclusion: The clinical examination was able to detect the patients at risk for aspiration pneumonia. The association of risk factors should lead the healthcare team to exercise more caution when planning the diet of the patient with pneumonia, as it can be the aspiration type.

[Guide of clinical management of HTLV patient: neurological aspects]. / Guia de manejo clínico do paciente com HTLV: aspectos neurológicos.

The Brazilian Ministry of Health (STD and Aids Program) invited specialists to make up an informative guide to deal with HTLV patients. Among the different topics, the neurological aspects associated to HTLV were contemplated. A suspected case should include changes in force and reflexes, distal paresthesiae and autonomic dysfunction. The investigation of such case should be based on the syndrome shown by the patient. For patients with spinal cord syndrome, magnetic resonance imaging or myelography as well as spinal fluid studies should be carried out. For patients with neuropathic or myopathic syndrome, electroneuromyography and CPK dosing should be done, and for those with autonomic syndrome, a search for postural hypotension, ultrasonography of urinary tract and urodynamic studies should be requested. The treatment may be symptomatic (spasticity, neurogenic bladder, intestinal constipation and neuropathic pain) and specific to be carried out in specialized centers.

Guia de manejo clínico do paciente com HTLV: aspectos neurológicos / Guide of clinical management of HTLV patient: neurological aspects

O Ministério da Saúde (Programa DST e Aids) reuniu especialistas para elaborar um guia informativo de manejo do paciente com HTLV. Dentre os diferentes tópicos, foram contemplados os aspectos neurológicos associados à infecção pelo HTLV. Um caso suspeito de doença neurológica associada ao HTLV deve incluir alteração de força e reflexos, parestesias distais e disfunção autonômica. A investigação do caso suspeito deve ser baseada na síndrome exibida pelo paciente. Para o paciente com síndrome medular, deve-se solicitar ressonância magnética da medula ou mielografia, assim como, estudo do líquor. Para o paciente com síndrome neuropática ou miopática, deve-se solicitar eletroneuromiografia e dosagem de CPK, e para aquele com síndrome autonômica, pesquisa de hipotensão postural, ultrassonografia das vias urinárias e estudo urodinâmico. O tratamento pode ser sintomático (espasticidade, bexiga neurogênica, constipação intestinal e dor neuropática) e específico a ser feito em centros especializados.

Adult T-cell leukemia/lymphoma associated with HTLV-1 infection in a Brazilian adolescent

We present the case of a 15-year-old patient infected with HTLV-1 who developed a cutaneous T-cell lymphoma, confirmed by histopathological and immunohistochemical examination, as well as clinically and hematologically confirmed leukemia. The patient died 3 months after initial presentation of the disease. The rarity of the disease in this age group justifies the present report