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1.
Biomed Res Int ; 2024: 3716786, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39130533

RESUMO

Background: Dengue fever (DF) is a mosquito-borne illness with substantial economic and societal impact. Understanding laboratory trends of hospitalized Dominican Republic (DR) pediatric patients could help develop screening procedures in low-resourced settings. We sought to describe laboratory findings over time in DR children with DF and DF severity from 2018 to 2020. Methods: Clinical information was obtained prospectively from recruited children with DF. Complete blood count (CBC) laboratory measures were assessed across Days 1-10 of fever. Participants were classified as DF-negative and DF-positive and grouped by severity. We assessed associations of DF severity with demographics, clinical characteristics, and peripheral blood studies. Using linear mixed-models, we assessed if hematologic values/trajectories differed by DF status/severity. Results: A total of 597 of 1101 with a DF clinical diagnosis were serologically evaluated, and 574 (471 DF-positive) met inclusion criteria. In DF, platelet count and hemoglobin were higher on earlier days of fever (p < = 0.0017). Eighty had severe DF. Severe DF risk was associated with thrombocytopenia, intraillness anemia, and leukocytosis, differing by fever day (p < = 0.001). Conclusions: In a pediatric hospitalized DR cohort, we found marked anemia in late stages of severe DF, unlike the typically seen hemoconcentration. These findings, paired with clinical symptom changes over time, may help guide risk-stratified screenings for resource-limited settings.


Assuntos
Vírus da Dengue , Dengue , Humanos , República Dominicana/epidemiologia , Dengue/epidemiologia , Dengue/sangue , Dengue/virologia , Dengue/diagnóstico , Masculino , Feminino , Pré-Escolar , Contagem de Células Sanguíneas , Lactente , Vírus da Dengue/isolamento & purificação , Criança , Epidemias , Anemia/epidemiologia , Anemia/sangue , Trombocitopenia/epidemiologia , Trombocitopenia/sangue , Trombocitopenia/virologia , Estudos Prospectivos
2.
Braz J Microbiol ; 55(2): 1801-1809, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38709438

RESUMO

Dengue necessitates accurate diagnosis. Rapid tests such as Bioline™ DENGUE DUO have gained traction, but validation in specific populations is essential. This study aimed to evaluate the performance of the Bioline™ test, alongside assessing the socio-epidemiological profile of symptomatic patients in a Brasília Military Hospital. The serum of 404 symptomatic patients was analyzed by the Bioline™ DENGUE DUO test, followed by Dengue virus detection and discrimination of the four serotypes by RT-qPCR. Accuracy was assessed using parameters including sensitivity (S), specificity (E), positive and negative predictive values (PPV and NPV), and positive (RV +) and negative (RV-) likelihood ratios. The NS1 component exhibited a sensitivity of 70.37%, a specificity of 97.30%, and an overall efficiency of 90.10% when compared to RT-qPCR as the gold standard. The IgM component demonstrated a sensitivity of 26.85%, a specificity of 89.53%, and an overall efficiency of 72.77% when compared to RT-qPCR as the gold standard. The IgG component demonstrated a sensitivity of 23.15%, a specificity of 68.92%, and an overall efficiency of 56.68% when compared to RT-qPCR as the gold standard. Several rapid tests are commercially available. However, considering variations across regions and demographic groups, it is important to question their accuracy in specific populations. Rapid tests are important screening tools, but they can have limitations for the certainty of diagnosis. Bioline™ DENGUE DUO displayed good specificity, but sensitivity was slightly below optimal levels. While helpful for confirming dengue, improvements are needed to effectively rule out the disease.


Assuntos
Vírus da Dengue , Dengue , Hospitais Militares , Sensibilidade e Especificidade , Humanos , Dengue/diagnóstico , Dengue/sangue , Dengue/virologia , Brasil/epidemiologia , Vírus da Dengue/imunologia , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , Anticorpos Antivirais/sangue , Criança , Idoso , Imunoglobulina M/sangue , Pré-Escolar , Kit de Reagentes para Diagnóstico/normas
3.
Braz J Infect Dis ; 28(3): 103746, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38703788

RESUMO

Immunodiagnostic tests for detecting dengue virus infections encounter challenges related to cross-reactivity with other related flaviviruses. Our research focuses on the development of a synthetic multiepitope antigen tailored for dengue immunodiagnostics. Selected dengue epitopes involved structural linearity and dissimilarity from the proteomes of Zika and Yellow fever viruses which served for computationally modeling the three-dimensional protein structure, resulting in the design of two proteins: rDME-C and rDME-BR. Both proteins consist of seven epitopes, separated by the GPGPG linker, and a carboxy-terminal 6 × -histidine tag. The molecular weights of the final proteins rDME-C and rDME-BR are 16.83 kDa and 16.80 kDa, respectively, both with an isoelectric point of 6.35. The distinguishing factor between the two proteins lies in the origin of their epitope sequences, where rDME-C is based on the reference dengue proteome, while rDME-BR utilizes sequences from prevalent Dengue genotypes in Brazil from 2008 to 2019. PyMol analysis revealed exposure of epitopes in the secondary structure. Successful expression of the antigens was achieved in soluble form and fluorescence experiments indicated a disordered structure. In subsequent testing, rDME-BR and rDME-C antigens were assessed using an indirect Elisa protocol against Dengue infected serum, previously examined with a commercial diagnostic test. Optimal concentrations for antigens were determined at 10 µg/mL for rDME-BR and 30 µg/mL for rDME-C, with serum dilutions ranging from 1:50 to 1:100. Both antigens effectively detected IgM and IgG antibodies in Dengue fever patients, with rDME-BR exhibiting higher sensitivity. Our in-house test showed a sensitivity of 77.3 % and 82.6 % and a specificity of 89.4 % and 71.4 % for rDME-C and rDEM-BR antigens. No cross-reactivity was observed with serum from Zika-infected mice but with COVID-19 serum samples. Our findings underscore the utility of synthetic biology in crafting Dengue-specific multiepitope proteins and hold promise for precise clinical diagnosis and monitoring responses to emerging Dengue vaccines.


Assuntos
Antígenos Virais , Vírus da Dengue , Dengue , Ensaio de Imunoadsorção Enzimática , Epitopos , Dengue/diagnóstico , Dengue/imunologia , Dengue/sangue , Antígenos Virais/imunologia , Epitopos/imunologia , Humanos , Vírus da Dengue/imunologia , Vírus da Dengue/genética , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Reações Cruzadas/imunologia , Sensibilidade e Especificidade
4.
Travel Med Infect Dis ; 59: 102699, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38452991

RESUMO

Dengue virus (DENV) is one of the most significant vector-borne pathogens worldwide. In this report, we describe clinical features and laboratory detection of dengue in a 45-year-old traveler to Nicaragua on return home to the United States in 2019. Clinical presentation was mild, with rash, headache, and fatigue, with only low-grade transient fever. Infection dynamics were documented by serology and PCR of serially collected body fluids. DENV serotype 2 was detected in whole blood 1 day after symptoms emerged, with viral RNA isolated to the red cell fraction, and remained detectable through day 89. DENV-2 RNA was detected in serum only on day 4, and IgM was undetectable on day 4 but evident by day 13. Viral RNA was also detected in urine. This report of DENV-2 RNA persistence in blood cells but only transient appearance in serum, supports the potential diagnostic value of whole blood over serum for PCR and opportunity of an expanded testing window. Informed testing approaches can improve diagnostic accuracy and inform strategies that preserve individual and public health.


Assuntos
Vírus da Dengue , Dengue , RNA Viral , Viagem , Humanos , Pessoa de Meia-Idade , Dengue/virologia , Dengue/diagnóstico , Dengue/sangue , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Imunoglobulina M/sangue , Nicarágua , RNA Viral/sangue , Sorogrupo
5.
Front Immunol ; 13: 793882, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35154111

RESUMO

In a world with an increasing population at risk of exposure to arthropod-borne flaviviruses, access to timely and accurate diagnostic tests would impact profoundly on the management of cases. Twenty peptides previously identified using a flavivirus proteome-wide microarray were evaluated to determine their discriminatory potential to detect dengue virus (DENV) infection. This included nine peptides recognized by IgM antibodies (PM peptides) and 11 peptides recognized by IgG antibodies (PG peptides). A bead-based multiplex peptide immunoassay (MPIA) using the Luminex technology was set-up to determine Ab binding levels to each of these peptides in a panel of 323 carefully selected human serum samples. Sera are derived from individuals either infected with different viruses, namely, the four DENV serotypes, Zika virus (ZIKV), yellow fever virus (YFV), chikungunya virus (CHIKV), West Nile virus (WNV) and Human immunodeficiency virus (HIV), or receiving vaccination against YFV, tick-borne encephalitis (TBEV), and Japanese encephalitis virus (JEV). Additionally, a set of healthy controls were included. We targeted a minimum specificity of 80% for all the analysis. The PG-9 peptide had the best sensitivity (73%) when testing DENV sera from acute patients (A-DENV; <8 days since symptom onset). With sera from convalescent DENV patients (C-DENV; >10 days since symptom onset) the FPG-1 peptide was the best seromarker with a sensitivity of 86%. When combining all A-DENV and C-DENV samples, peptides PM-22 and FPG-1 had the best-diagnostic performance with a sensitivity of 60 and 61.1%, and areas under the curve (AUC) of 0.7865 and 0.8131, respectively. A Random forest (RF) algorithm was used to select the best combination of peptides to classify DENV infection at a targeted specificity >80%. The best RF model for PM peptides that included A-DENV and C-DENV samples, reached a sensitivity of 72.3%, while for PG peptides, the best RF models for A-DENV only, C-DENV only and A-DENV + C-DENV reached a sensitivity of 88.9%, 89.1%, and 88.3%, respectively. In conclusion, the combination of multiple peptides constitutes a founding set of seromarkers for the discrimination of DENV infected individuals from other flavivirus infections.


Assuntos
Biomarcadores , Vírus da Dengue/fisiologia , Dengue/diagnóstico , Dengue/microbiologia , Peptídeos , Proteínas Virais , Adolescente , Adulto , Idoso , Anticorpos Antivirais , Biomarcadores/sangue , Criança , Pré-Escolar , Dengue/sangue , Dengue/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Peptídeos/sangue , Peru/epidemiologia , Prognóstico , Proteoma , Proteômica/métodos , Curva ROC , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Proteínas Virais/sangue , Adulto Jovem
6.
Platelets ; 33(2): 176-183, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-34027810

RESUMO

Dengue virus (DENV) infection is responsible for the development of dengue illness, which can be either asymptomatic, present mild manifestations or evolve to severe dengue. Thrombocytopenia is an important characteristic during DENV infection, being observed both in mild and severe dengue, although the lowest platelet counts are encountered during severe cases. This review gathers information regarding several mechanisms that have been related to alterations in platelet number and function, leading to thrombocytopenia but also platelet-mediated immune and inflammatory response. On this regard, we highlight that the decrease in platelet counts may be due to bone marrow suppression or consumption of platelets at the periphery. We discuss the infection of hematopoietic progenitors and stromal cells as mechanisms involved in bone marrow suppression. Concerning peripheral consumption of platelets, we addressed the direct infection of platelets by DENV, adhesion of platelets to leukocytes and vascular endothelium and platelet clearance mediated by anti-platelet antibodies. We also focused on platelet involvement on the dengue immunity and pathogenesis through translation and secretion of viral and host factors and through platelet-leukocyte aggregates formation. Hence, the present review highlights important findings related to platelet activation and thrombocytopenia during dengue infection, and also exhibits different mechanisms associated with decreased platelet counts.Graphical abstract:Schematic mechanistic representation of platelet-mediated immune responses and thrombocytopenia during dengue infection. (A) DENV-infected platelets secrete cytokines and chemokines and also adhere to activated vascular endothelium. Platelets aggregate with leukocytes, inducing the secretion of NETs and inflammatory mediators by neutrophils and monocytes, respectively. (B) DENV directly infects stromal cells and hematopoietic precursors, including megakaryocytes, which compromises megakaryopoiesis. Both central and peripheric mechanisms contribute to DENV-associated thrombocytopenia.


Assuntos
Plaquetas/fisiologia , Vírus da Dengue/patogenicidade , Dengue/sangue , Contagem de Plaquetas/métodos , Trombocitopenia/fisiopatologia , Feminino , Humanos , Masculino
7.
Viruses ; 13(9)2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34578370

RESUMO

The incidence of dengue in Latin America has increased dramatically during the last decade. Understanding the pathogenic mechanisms in dengue is crucial for the identification of biomarkers for the triage of patients. We aimed to characterize the profile of cytokines (IFN-γ, TNF-α, IL-1ß, IL-6, IL-18 and IL-10), chemokines (CXCL8/IL-8, CCL2/MCP-1 and CXCL10/IP-10) and coagulation mediators (Fibrinogen, D-dimer, Tissue factor-TF, Tissue factor pathway inhibitor-TFPI and Thrombomodulin) during the dengue-4 epidemic in Brazil. Laboratory-confirmed dengue cases had higher levels of TNF-α (p < 0.001), IL-6 (p = 0.005), IL-10 (p < 0.001), IL-18 (p = 0.001), CXCL8/IL-8 (p < 0.001), CCL2/MCP-1 (p < 0.001), CXCL10/IP-10 (p = 0.001), fibrinogen (p = 0.037), D-dimer (p = 0.01) and TFPI (p = 0.042) and lower levels of TF (p = 0.042) compared to healthy controls. A principal component analysis (PCA) distinguished between two profiles of mediators of inflammation and coagulation: protective (TNF-α, IL-1ß and CXCL8/IL-8) and pathological (IL-6, TF and TFPI). Lastly, multivariate logistic regression analysis identified high aspartate aminotransferase-to-platelet ratio index (APRI) as independent risk factors associated with severity (adjusted OR: 1.33; 95% CI 1.03-1.71; p = 0.027), the area under the receiver operating characteristics curve (AUC) was 0.775 (95% CI 0.681-0.869) and an optimal cutoff value was 1.4 (sensitivity: 76%; specificity: 79%), so it could be a useful marker for the triage of patients attending primary care centers.


Assuntos
Fatores de Coagulação Sanguínea/imunologia , Quimiocinas/sangue , Citocinas/sangue , Vírus da Dengue/imunologia , Dengue/imunologia , Índice de Gravidade de Doença , Adulto , Biomarcadores/sangue , Fatores de Coagulação Sanguínea/classificação , Brasil , Quimiocinas/classificação , Quimiocinas/imunologia , Citocinas/classificação , Citocinas/imunologia , Dengue/sangue , Feminino , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade
8.
Viruses ; 13(8)2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34452405

RESUMO

Transcriptomics, proteomics and pathogen-host interactomics data are being explored for the in silico-informed selection of drugs, prior to their functional evaluation. The effectiveness of this kind of strategy has been put to the test in the current COVID-19 pandemic, and it has been paying off, leading to a few drugs being rapidly repurposed as treatment against SARS-CoV-2 infection. Several neglected tropical diseases, for which treatment remains unavailable, would benefit from informed in silico investigations of drugs, as performed in this work for Dengue fever disease. We analyzed transcriptomic data in the key tissues of liver, spleen and blood profiles and verified that despite transcriptomic differences due to tissue specialization, the common mechanisms of action, "Adrenergic receptor antagonist", "ATPase inhibitor", "NF-kB pathway inhibitor" and "Serotonin receptor antagonist", were identified as druggable (e.g., oxprenolol, digoxin, auranofin and palonosetron, respectively) to oppose the effects of severe Dengue infection in these tissues. These are good candidates for future functional evaluation and clinical trials.


Assuntos
Antivirais/uso terapêutico , Dengue/tratamento farmacológico , Transcriptoma , Adenosina Trifosfatases/antagonistas & inibidores , Antagonistas Adrenérgicos/farmacologia , Antagonistas Adrenérgicos/uso terapêutico , Antivirais/farmacologia , Encéfalo/metabolismo , Simulação por Computador , Dengue/sangue , Dengue/genética , Dengue/metabolismo , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Reposicionamento de Medicamentos , Humanos , Fígado/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , NF-kappa B/metabolismo , Antagonistas da Serotonina/farmacologia , Antagonistas da Serotonina/uso terapêutico , Dengue Grave/sangue , Dengue Grave/tratamento farmacológico , Dengue Grave/genética , Dengue Grave/metabolismo , Baço/metabolismo
9.
Front Immunol ; 12: 686691, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34290707

RESUMO

Dengue is a major public health problem in tropical and sub-tropical regions worldwide. Since the Zika epidemic and the increased co-circulation of other arboviruses, the serology-based diagnosis of dengue has become more problematic due to the high antigenic resemblance, especially among the flavivirus family. Therefore, a more comprehensive understanding of the diversity, specificity and temporal evolution of the antibody response following dengue infection is needed. In order to close this knowledge gap, we used a high-density peptide microarray of 9,072 linear peptides covering the entire proteome diversity of dengue, Zika, yellow fever and chikungunya viruses. The IgM and IgG antibody responses were measured against the designed microarray in symptomatic dengue infected individuals from an arbovirus endemic area in Peru and in overseas travelers returning to Belgium, as representatives of multiple-exposed and primary infections, respectively. Serum samples were collected longitudinally across four time points over the period of six months in Peru and over two time points in travelers. We show that epitopes eliciting the strongest flavivirus cross-reactive antibodies, in both primary and secondary infections were concentrated in the capsid, E, NS1, NS3 and NS5 proteins. The IgG antibody responses against NS1 and NS3 followed a rise-and-fall pattern, with peak titers between two to four weeks after onset of illness. The response to the E and NS5 proteins increased rapidly in the acute phase and was maintained at stable levels until at least 6 months after illness. A more scattered IgM antibody reactivity across the viral proteome was observed in the acute phase of the disease and that persisted through the 6-month window. The magnitude, breadth (i.e. number of unique epitopes targeted) and depth (i.e. number of epitope variants recognized) of the IgG response was higher in secondary infections compared to primary infections. For IgM antibodies, the magnitude of the response was higher in primary infected individuals whereas the breadth and depth of the response was lower in this group compared with the endemic subjects. Finally, through this arboviral proteome-wide epitope mapping, we were able to identify IgM and IgG dengue-specific epitopes which can be useful serological markers for dengue diagnosis and serostatus determination.


Assuntos
Anticorpos Antivirais/imunologia , Vírus da Dengue/imunologia , Dengue/imunologia , Epitopos/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Adolescente , Adulto , Anticorpos Antivirais/sangue , Bélgica , Reações Cruzadas/imunologia , Dengue/sangue , Vírus da Dengue/genética , Ensaio de Imunoadsorção Enzimática , Epitopos/química , Feminino , Flavivirus/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Peru , Testes Sorológicos , Viagem , Adulto Jovem
10.
Am J Trop Med Hyg ; 105(3): 745-750, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34242180

RESUMO

The differentiation between dengue and COVID-19 diagnoses is a challenge in tropical regions because of the similarity of symptoms and limited access to specific diagnostic tests for each disease. The objective of this study was to describe the initial symptoms and laboratory test values of patients who presented to the emergency department with dengue or COVID-19. A cross-sectional study was performed in a single center in Cali, Colombia. The inclusion criteria were patients with a diagnosis of dengue or COVID-19 who were older than 14 years of age. All patients experienced fever or other symptoms for fewer than 10 days. Linear regression was performed to evaluate the differences in the neutrophil-lymphocyte ratio (NLR) between patients diagnosed with COVID-19 and dengue, and was adjusted for sex and age group (≤ 31 and > 31 years). The sample size was calculated to test the hypothesis that the median NLR in COVID-19 patients is higher than that in dengue patients. A P value < 0.05 was considered statistically significant for all analyses. A total of 93 patients were included: 70 with dengue and 23 with COVID-19. Dengue patients were younger than COVID-19 patients. There were significant differences between dengue and COVID-19 patients regarding platelet count (P < 0.01), neutrophil count (P < 0.01), NLR (P < 0.01), and abnormal alanine transaminase (ALT) (P = 0.03). The NLR was significantly higher in COVID-19 patients than in dengue patients (P < 0.01). In conclusion, during the first week of symptoms, absolute neutrophil count, NLR, and platelet count could help guide the initial differential approach between dengue and COVID-19. These findings could be useful in geographical areas with a lack of resources.


Assuntos
COVID-19/diagnóstico , Dengue/diagnóstico , SARS-CoV-2 , Adolescente , Adulto , COVID-19/sangue , Estudos Transversais , Dengue/sangue , Diagnóstico Diferencial , Feminino , Humanos , Linfócitos , Masculino , Pessoa de Meia-Idade , Neutrófilos , Adulto Jovem
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