Performance of the National Institute of Infectious Diseases disability scale in HTLV-1-associated myelopathy/tropical spastic paraparesis.

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic disabling disease. However, there is a lack of an adequate and specific health measurement instrument validated and with good performance to assess their degree of physical disability. This led us to carry out this study and to evaluate the performance of Fiocruz's National Institute of Infectious Diseases (IDS) disability scale, a specific instrument for HAM/TSP. Ninety-two HAM/TSP patients participated in the study. One researcher applied the IDS, IPEC scale, Disability Status Scale (DSS), Expanded DSS (EDSS), Osame scale, Beck Depression Inventory, and the WHOQOL-BREF questionnaire. In parallel, blindly, and separately, other researchers applied the IDS. An inter-rater reliability analysis of the IDS, correlation analysis with the other scales, and depression and quality of life questionnaires were performed. The applicability of the IDS was also evaluated. The IDS showed high reliability in all scores. The inter-rater reliability test for the total IDS score was 0.94 (0.82-0.98) on its four dimensions. The scale adequately indicated the different degrees of disability, presenting a distribution similar to normal. There was a high correlation with the other scales (Spearman coefficients > 0.80, p < 0.001). The scale had good acceptance among users and a short application time. IDS for HAM/TSP was reliable, consistent, easy, and fast to use. It can be used for both prospective evaluations and clinical trials. The present study supports the IDS as a valid instrument to measure disability in patients with HAM/TSP compared to previously used scales.

Neurological Phenotypes of IRF2BPL Gene Variants: A Report of Four Novel Variants.

IRF2BPL gene variants have recently been associated to developmental disability and epilepsy in children and movement disorders in adults. So far, only few cases have been reported; here we present four novel cases identified by exome sequencing, while investigating developmental delay, adult-onset cerebellar ataxia or regression.

Putative role of HLA polymorphism among a Brazilian HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) population.

Around ten million people are infected with HTLV-1 worldwide, and 1-4% develop HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), characterized by an important degeneration of the spinal cord, which can lead to death. Distinct HLA alleles have been associated with either HAM/TSP susceptibility or protection. However, these HLA alleles set may change according to the population studied. Brazil is the second country in the number of HTLV-1-infected people and there are few reports addressing the HLA influence on HTLV-1 infection as well as on disease outcome. The objective of this study was to evaluate the influence of HLA alleles as a risk factor for HAM/TSP and the proviral load (PVL) levels, clinical progression, and death outcomes in an admixed Brazilian population. The HLA-A, -B, -C, and -DRB1 were genotyped in 375 unrelated HTLV-1-infected individuals divided into asymptomatic carriers (AC) (n = 165) and HAM/TSP (n = 210) in a longitudinal cohort from 8 to 22 years of follow-up. Because locus B deviated from Hardy-Weinberg Equilibrium for the study groups, the results represented for HLA-B alleles were inconclusive. The alleles HLA-A*68 and -C*07 were related to HAM/TSP risk in multivariate analysis. The alleles HLA-A*33, and -A*36 were associated with protection against disease progression in HAM/TSP patients, while -C*12, -C*14, and -DRB1*08 were associated with increased risk of death. In the AC group, the presence of, -C*06 and -DRB1*15 alleles influenced an increased PVL, in an adjusted linear regression model, while -A*30, -A*34, -C*06, -C*17 and -DRB1*09 alleles were associated with increased PVL in HAM/TSP group compared to HAM/TSP individuals not carrying these alleles. All these alleles were also related to increased PVL associated with clinical progression outcome. Increased PVL associated with the death outcome was linked to the presence of HLA-A*30. PVL has been associated with HLA, and several alleles were related in AC and HAM/TSP patients with or without interacting with clinical progression outcomes. Understanding the prognostic value of HLA in HAM/TSP pathogenesis can provide important biomarkers tools to improve clinical management and contribute to the discovery of new therapeutic interventions.

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.

Efficacy of Corticosteroid Therapy for HTLV-1-Associated Myelopathy: A Randomized Controlled Trial (HAMLET-P).

Corticosteroids are most commonly used to treat HTLV-1-associated myelopathy (HAM); however, their clinical efficacy has not been tested in randomized clinical trials. This randomized controlled trial included 8 and 30 HAM patients with rapidly and slowly progressing walking disabilities, respectively. Rapid progressors were assigned (1:1) to receive or not receive a 3-day course of intravenous methylprednisolone in addition to oral prednisolone therapy. Meanwhile, slow progressors were assigned (1:1) to receive oral prednisolone or placebo. The primary outcomes were a composite of ≥1-grade improvement in the Osame Motor Disability Score or ≥30% improvement in the 10 m walking time (10 mWT) at week 2 for rapid progressors and changes from baseline in 10 mWT at week 24 for slow progressors. In the rapid progressor trial, all four patients with but only one of four without intravenous methylprednisolone achieved the primary outcome (p = 0.14). In the slow progressor trial, the median changes in 10 mWT were -13.8% (95% CI: -20.1--7.1; p < 0.001) and -6.0% (95% CI: -12.8-1.3; p = 0.10) with prednisolone and placebo, respectively (p for between-group difference = 0.12). Whereas statistical significance was not reached for the primary endpoints, the overall data indicated the benefit of corticosteroid therapy. (Registration number: UMIN000023798, UMIN000024085).

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.

Meningeal Sporotrichosis Due to Sporothrix brasiliensis: A 21-Year Cohort Study from a Brazilian Reference Center.

Meningeal sporotrichosis is rare and occurs predominantly in immunosuppressed individuals. This retrospective study explored clinical and laboratory characteristics, treatment, and prognosis of patients with disseminated sporotrichosis who underwent lumbar puncture (LP) at a Brazilian reference center from 1999 to 2020. Kaplan-Meier and Cox regression models were used to estimate overall survival and hazard ratios. Among 57 enrolled patients, 17 had meningitis. Fifteen (88.2%) had HIV infection, and in 6 of them, neurological manifestations occurred because of the immune reconstitution inflammatory syndrome (IRIS). The most frequent symptom was headache (88.2%). Meningeal symptoms at first LP were absent in 7/17 (41.2%) patients. Sporothrix was diagnosed in cerebrospinal fluid either by culture or by polymerase chain reaction in seven and four patients, respectively. All but one patient received prolonged courses of amphotericin B formulations, and seven received posaconazole, but relapses were frequent. Lethality among patients with meningitis was 64.7%, with a higher chance of death compared to those without meningitis (HR = 3.87; IC95% = 1.23;12.17). Meningeal sporotrichosis occurs mostly in people with HIV and can be associated with IRIS. Screening LP is indicated in patients with disseminated disease despite the absence of neurological complaints. Meningitis is associated with poor prognosis, and better treatment strategies are needed.

Following the Clues: Usefulness of Biomarkers of Neuroinflammation and Neurodegeneration in the Investigation of HTLV-1-Associated Myelopathy Progression.

Human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a neurodegenerative disease due to axonal damage of the corticospinal secondary to an inflammatory response against infected T-cells. In the present work, we aimed to evaluate biomarkers of neurodegeneration and neuroinflammation in the definition of HAM/TSP prognosis. Neurofilament light (NfL) and phosphorylated heavy (pNfH) chains, total Tau protein, cellular prion protein (PrPc), inflammatory chemokines, and neopterin were quantified in paired cerebrospinal fluid (CSF) and serum samples from HAM/TSP patients (n=21), HTLV-1 asymptomatic carriers (AC) (n=13), and HTLV-1 seronegative individuals with non-inflammatory non-degenerative neurological disease (normal-pressure hydrocephalus) (n=9) as a control group. HTLV-1 proviral load in peripheral blood mononuclear cells and the expression of chemokine receptors CCR4, CCR5, and CXCR3 in infected CD4+ T-cells (HTLV-1 Tax+ cells) were also assessed. CSF levels of Tau, NfL, and pNfH were similar between groups, but PrPc and neopterin were elevated in HAM/TSP patients. Most individuals in the control group and all HTLV-1 AC had CSF/serum neopterin ratio < 1.0, and two-thirds of HAM/TSP patients had ratio values > 1.0, which positively correlated with the speed of disease progression and pNfH levels, indicating active neuroinflammation. HAM/TSP patients showed high serum levels of CXCR3-binding chemokines (CXCL9, CXCL10, and CXCL11) and elevated CSF levels of CCL2, CCL3, CCL4, CCL17, CXCL5, CXCL10, and CXCL11. Indeed, CXCL10 concentration in CSF of HAM/TSP patients was 5.8-fold and 8.7-fold higher in than in HTLV-1 AC and controls, respectively, and correlated with CSF cell counts. HAM/TSP patients with typical/rapid disease progression had CSF/serum CXCL10 ratio > 1.0 and a higher frequency of CXCR3+Tax+CD4+ T-cells in blood, which indicated a positive gradient for the migration of infected cells and infiltration into the central nervous system. In conclusion, the slow progression of HAM/TSP abrogates the usefulness of biomarkers of neuronal injury for the disease prognosis. Thus, markers of inflammation provide stronger evidence for HAM/TSP progression, particularly the CSF/serum neopterin ratio, which may contribute to overcome differences between laboratory assays.

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.

Management of HAM/TSP: Systematic Review and Consensus-based Recommendations 2019.

PURPOSE OF REVIEW: To provide an evidence-based approach to the use of therapies that are prescribed to improve the natural history of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP)-a rare disease. RECENT FINDINGS: All 41 articles on the clinical outcome of disease-modifying therapy for HAM/TSP were included in a systematic review by members of the International Retrovirology Association; we report here the consensus assessment and recommendations. The quality of available evidence is low, based for the most part on observational studies, with only 1 double-masked placebo-controlled randomized trial. SUMMARY: There is evidence to support the use of both high-dose pulsed methyl prednisolone for induction and low-dose (5 mg) oral prednisolone as maintenance therapy for progressive disease. There is no evidence to support the use of antiretroviral therapy. There is insufficient evidence to support the use of interferon-α as a first-line therapy.

Inflammatory Cytokine Patterns Associated with Neurological Diseases in Coronavirus Disease 2019.

Patients with coronavirus disease 2019 (COVID-19) can present with distinct neurological manifestations. This study shows that inflammatory neurological diseases were associated with increased levels of interleukin (IL)-2, IL-4, IL-6, IL-10, IL-12, chemokine (C-X-C motif) ligand 8 (CXCL8), and CXCL10 in the cerebrospinal fluid. Conversely, encephalopathy was associated with high serum levels of IL-6, CXCL8, and active tumor growth factor ß1. Inflammatory syndromes of the central nervous system in COVID-19 can appear early, as a parainfectious process without significant systemic involvement, or without direct evidence of severe acute respiratory syndrome coronavirus 2 neuroinvasion. At the same time, encephalopathy is mainly influenced by peripheral events, including inflammatory cytokines. ANN NEUROL 2021;89:1041-1045.

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.

Bioimpedância em doenças infecciosas: revisão crítica / Bioimpedance in infectious diseases: critical review

Objetivo: verificar se o ângulo de fase, obtido por bioimpedância elétrica, pode ser utilizado como indicador prognóstico em doenças infecciosas e em quais dessas doenças seu uso está adequadamente embasado pela literatura científica. Métodos: revisão integrativa realizada por meio das bases de dados, como google acadêmico, na BVS Brasil, nas bases SciELO, LILACS e Pubmed, utilizando o termo para busca (bioimpedância e doenças infectocontagiosas e bioimpedância) AND (bioimpedance and infectious diseases OR bioimpedance). A seleção dos estudos foi feita, considerando artigos originais completos disponíveis on-line, em inglês, espanhol e português, publicados entre 2007 e 2021. Resultados: todos os estudos considerados (793) foram realizados em adultos com doença infecciosa. Destes 28 (3,5%) foram separados para leitura aprofundada sobre o perfil metodológico, e apenas quatro (0,50%) do total de artigos consideraram o ângulo de fase como índice prognóstico para doenças infeciosas, ambos em pacientes HIV + hospitalizados. Conclusão: A bioimpedância vem sendo considerada como instrumento de avaliação de estado nutricional em pacientes com doenças infecciosas. Mas o uso do ângulo de fase vem sendo pouco estudado como índice prognóstico para essa população, não podendo ser considerado adequadamente embasado para uso clínico na população com doença infecciosa, o que suscita maior atenção a esta população e a necessidade de maior investigação científica.

Objective: to verify if the phase angle obtained by electrical bioimpedance can be used as a prognostic indicator in infectious diseases and in which infectious diseases its use is adequately supported by scientific literature. Methods: integrative review conducted using databases such as Google Scholar, BVS Brazil, SciELO, LILACS and Pubmed, using the search term (bioimpedance and infectious diseases and bioimpedance) AND (bioimpedance and infectious diseases OR bioimpedance). The selection of studies was made considering complete original articles available online, in English, Spanish and Portuguese, published between 2007 and 2021. Results: all studies considered (793) were carried out in adults with infectious disease. Of these, 28 (3.5%) were separated for in-depth reading on the methodological profile, and only four (0.50%) of the total articles considered the phase angle as a prognostic index for infectious diseases, both in hospitalized HIV + patients. Conclusion: Bioimpedance has been considered as an instrument to assess nutritional status in patients with infectious diseases. However, the use of the phase angle has been little studied as a prognostic index for this population, and cannot be considered adequately substantiated for clinical use in the population with infectious disease, which raises more attention to this population and the need for further scientific investigation.

Isolated intracranial hypertension associated with COVID-19.

BACKGROUND: Headache is a frequent complaint in COVID-19 patients. However, no detailed information on headache characteristics is provided in these reports. Our objective is to describe the characteristics of headache and the cerebrospinal fluid (CSF) profile in COVID-19 patients, highlighting the cases of isolated intracranial hypertension. METHODS: In this cross-sectional study, we selected COVID-19 patients who underwent lumbar puncture due to neurological complaints from April to May 2020. We reviewed clinical, imaging, and laboratory data of patients with refractory headache in the absence of other encephalitic or meningitic features. CSF opening pressures higher than 250 mmH2O were considered elevated, and from 200 to 250 mmH2O equivocal. RESULTS: Fifty-six COVID-19 patients underwent lumbar puncture for different neurological conditions. A new, persistent headache that prompted a CSF analysis was diagnosed in 13 (23.2%). The pain was throbbing, holocranial or bilateral in the majority of patients. All patients had normal CSF analysis and RT-qPCR for SARS-CoV-2 was negative in all samples. Opening pressure >200 mmH2O was present in 11 patients and, in six of these, > 250 mmH2O. 6/13 patients had complete improvement of the pain, five had partial improvement, and two were left with a daily persistent headache. CONCLUSIONS: In a significant proportion of COVID-19 patients, headache was associated to intracranial hypertension in the absence of meningitic or encephalitic features. Coagulopathy associated with COVID-19 could be an explanation, but further studies including post-mortem analysis of areas of production and CSF absorption (choroid plexuses and arachnoid granulations) are necessary to clarify this issue.