Central and Peripheral Nervous System Manifestations Associated with Dengue Illness.

Dengue illness, caused by the dengue viruses, continues to be a major global health concern, with increasing incidence and the emergence of severe manifestations such as neurological complications. An overview of the current understanding of dengue epidemiology, clinical manifestations, and research priorities is presented here. Dengue transmission has escalated in recent years, exacerbated by factors such as vector expansion, climate change, and socioeconomic challenges. The clinical spectrum of dengue ranges from mild febrile illness to severe manifestations, including hemorrhagic fever and neurological complications. Neurological manifestations of dengue, once considered rare, are now increasingly reported, encompassing encephalitis, myelitis, and Guillain-Barré Syndrome, among others. Diagnosis primarily relies on laboratory methods such as RT/PCR, NS1 antigen detection, and serological assays. Despite advancements in understanding the dengue pathogenesis, there remains a critical need for effective vaccines, antiviral drugs, improved surveillance methods, predictive models for disease severity, and long-term studies on post-Dengue sequelae. Integrated programs and holistic approaches to dengue control are essential for mitigating its impact. Addressing these research priorities will be pivotal in combating dengue and reducing its global burden.

In vitro analysis of VEGF-mediated endothelial permeability and the potential therapeutic role of Anti-VEGF in severe dengue.

Background: Vascular endothelial growth factor (VEGF) is one of the proteins involved in dengue immunopathogenesis. It is overexpressed in severe dengue and contributes to vascular permeability and plasma leakage. In this study, we investigated the effects of VEGF and anti-VEGF treatments on endothelial cells in vitro, to assess the potential use of anti-VEGF antibodies in managing severe dengue. Methods: Human pulmonary microvascular endothelial cells were treated with VEGF and a VEGF/anti-VEGF combination. The effects of the treatments were studied using an endothelial permeability assay and microarray gene expression profiling. In the permeability assay, the fluorescein isothiocyanate (FITC)-dextran fluorescence signal across the endothelial monolayer was recorded, and the cells were stained with PECAM-1 to detect gap formation. RNA was extracted from treated cells for microarray gene profiling and analysis. The results were analyzed for differentially expressed genes (DEGs) and gene enrichment analysis. The DEGs were subjected to STRING to construct the protein-protein interaction network and then Cytoscape to identify the hub genes. Results: VEGF-treated endothelial cells showed greater movement of FITC-dextran across the monolayer than VEGF/anti-VEGF-treated cells. There were 111 DEGs for VEGF-treated cells and 118 DEGs for VEGF/anti-VEGF-treated cells. The genes upregulated in VEGF-treated cells were enriched in inflammatory responses and regulation of the endothelial barrier, nitric oxide synthesis, angiogenesis, and the nucleotide-binding oligomerization domain-like receptor signaling pathway. Top 10 hub genes were identified from the DEGs. Conclusions: VEGF treatment increased permeability across endothelial cells, while anti-VEGF reduced this leakage. Analysis of VEGF-treated endothelial cells identified hub genes implicated in severe dengue. The top 10 hub genes were TNF, IL1B, IL6, CCL2, PTGS2, ICAM1, CXCL2, CXCL1, CSF2, and TLR2. The results of this study show that using anti-VEGF antibodies to neutralize VEGF may be a promising therapy to prevent the progression of dengue to severe dengue.

Dengue NS1 interaction with lipids alters its pathogenic effects on monocyte derived macrophages.

BACKGROUND: While dengue NS1 antigen has been shown to be associated with disease pathogenesis in some studies, it has not been linked in other studies, with the reasons remaining unclear. NS1 antigen levels in acute dengue are often associated with increased disease severity, but there has been a wide variation in results based on past dengue infection and infecting dengue virus (DENV) serotype. As NS1 engages with many host lipids, we hypothesize that the type of NS1-lipid interactions alters its pathogenicity. METHODS: Primary human monocyte derived macrophages (MDMs) were co-cultured with NS1 alone or with HDL, LDL, LPS and/or platelet activating factor (PAF) from individuals with a history of past dengue fever (DF = 8) or dengue haemorrhagic fever (DHF = 8). IL-1ß levels were measured in culture supernatants, and gene expression analysis carried out in MDMs. Monocyte subpopulations were assessed by flow cytometry. Hierarchical cluster analysis with Euclidean distance calculations were used to differentiate clusters. Differentially expressed variables were extracted and a classifier model was developed to differentiate between past DF and DHF. RESULTS: Significantly higher levels of IL-1ß were seen in culture supernatants when NS1 was co-cultured with LDL (p = 0.01, median = 45.69 pg/ml), but lower levels when NS1 was co-cultured with HDL (p = 0.05, median = 4.617 pg/ml). MDMs of those with past DHF produced higher levels of IL-1ß when NS1 was co-cultured with PAF (p = 0.02). MDMs of individuals with past DHF, were significantly more likely to down-regulate RPLP2 gene expression when macrophages were co-cultured with either PAF alone, or NS1 combined with PAF, or NS1 combined with LDL. When NS1 was co-cultured with PAF, HDL or LDL two clusters were detected based on IL10 expression, but these did not differentiate those with past DF or DHF. CONCLUSIONS: As RPLP2 is important in DENV replication, regulating cellular stress responses and immune responses and IL-10 is associated with severe disease, it would be important to further explore how differential expression of RPLP2 and IL-10 could lead to disease pathogenesis based on NS1 and lipid interactions.

Predictors of acute kidney injury in dengue patients: a systematic review and meta-analysis.

BACKGROUND: Dengue infection poses a significant global health challenge, particularly in tropical and subtropical regions. Among its severe complications, Acute kidney injury (AKI) stands out due to its association with increased morbidity, mortality, and healthcare burdens. This Meta-analysis aim to identify and evaluate the predictors of AKI among dengue patients, facilitating early detection and management strategies to mitigate AKI's impact. METHODS: We searched PubMed, EMBASE, and Web of Science databases, covering literature up to February 2024. We included human observational studies reporting on AKI predictors in confirmed dengue cases. Nested-Knowledge software was used for screening and data extraction. The Newcastle-Ottawa Scale was used for quality assessment. R software (V 4.3) was utilized to compute pooled odds ratios (ORs) and 95% confidence intervals (CIs) for each predictor. RESULTS: Our search yielded nine studies involving diverse geographic locations and patient demographics. A total of 9,198 patients were included in the studies, with 542 diagnosed with AKI. in which key predictors of AKI identified include severe forms of dengue (OR: 2.22, 95% CI: 1.02-3.42), male gender (OR: 3.13, 95% CI: 1.82-4.44), comorbidities such as diabetes mellitus (OR: 3.298, 95% CI: 0.274-6.322), and chronic kidney disease (OR: 2.2, 95% CI: 0.42-11.24), as well as co-infections and clinical manifestations like rhabdomyolysis and major bleeding. CONCLUSION: Our study identifies several predictors of AKI in dengue patients. These findings indicate the importance of early identification and intervention for high-risk individuals. Future research should focus on standardizing AKI diagnostic criteria within the dengue context and exploring the mechanisms underlying these associations to improve patient care and outcomes.

An effective pan-serotype dengue vaccine and enhanced control strategies could help in reducing the severe dengue burden in Bangladesh-A perspective.

Dengue is an important vector-borne disease occurring globally. Dengue virus (DENV) infection can result in a potentially life-threatening disease. To date, no DENV-specific antiviral treatment is available. Moreover, an equally effective pan-serotype dengue virus vaccine is not available. Recently, two DENV vaccines, Dengvaxia and Qdenga, were licensed for limited use. However, none of them have been approved in Bangladesh. DENV is transmitted by Aedes mosquitoes, and global warming caused by climate change favoring Aedes breeding plays an important role in increasing DENV infections in Bangladesh. Dengue is a serious public health concern in Bangladesh. In the year 2023, Bangladesh witnessed its largest dengue outbreak, with the highest number of dengue cases (n = 321,179) and dengue-related deaths (n = 1,705) in a single epidemic year. There is an increased risk of severe dengue in individuals with preexisting DENV-specific immunoglobulin G if the individuals become infected with different DENV serotypes. To date, vector control has remained the mainstay for controlling dengue; therefore, an immediate, strengthened, and effective vector control program is critical and should be regularly performed for controlling dengue outbreaks in Bangladesh. In addition, the use of DENV vaccine in curbing dengue epidemics in Bangladesh requires more consideration and judgment by the respective authority of Bangladesh. This review provides perspectives on the control and prevention of dengue outbreaks. We also discuss the challenges of DENV vaccine use to reduce dengue epidemics infection in Bangladesh.

Kinetics of cardiovascular and inflammatory biomarkers in paediatric dengue shock syndrome.

Glycocalyx disruption and hyperinflammatory responses are implicated in the pathogenesis of dengue-associated vascular leak, however little is known about their association with clinical outcomes of patients with dengue shock syndrome (DSS). We investigated the association of vascular and inflammatory biomarkers with clinical outcomes and their correlations with clinical markers of vascular leakage. We performed a prospective cohort study in Viet Nam. Children ≥5 years of age with a clinical diagnosis of DSS were enrolled into this study. Blood samples were taken daily during ICU stay and 7-10 days after hospital discharge for measurements of plasma levels of Syndecan-1, Hyaluronan, Suppression of tumourigenicity 2 (ST-2), Ferritin, N-terminal pro Brain Natriuretic Peptide (NT-proBNP), and Atrial Natriuretic Peptide (ANP). The primary outcome was recurrent shock. Ninety DSS patients were enrolled. Recurrent shock occurred in 16 patients. All biomarkers, except NT-proBNP, were elevated at presentation with shock. There were no differences between compensated and decompensated DSS patients. Glycocalyx markers were positively correlated with inflammatory biomarkers, haematocrit, percentage haemoconcentration, and negatively correlated with stroke volume index. While Syndecan-1, Hyaluronan, Ferritin, and ST-2 improved with time, ANP continued to be raised at follow-up. Enrolment Syndecan-1 levels were observed to be associated with developing recurrent shock although the association did not reach the statistical significance at the P < 0.01 (OR = 1.82, 95% CI 1.07-3.35, P = 0.038). Cardiovascular and inflammatory biomarkers are elevated in DSS, correlate with clinical vascular leakage parameters and follow different kinetics over time. Syndecan-1 may have potential utility in risk stratifying DSS patients in ICU.

Differential Proteomic Profiling at Different Phases of Dengue Infection: An Intricate Insight from Proteins to Pathogenesis.

Dengue fever is a rapidly emerging tropical disease and an important cause of morbidity in its severe form worldwide. A wide spectrum of the pathophysiology is associated with the transition of dengue fever to severe dengue, which is driven by the host immune response and might reflect in patients' proteome profile. This study aims to analyze the plasma from different phases of dengue-infected patients at two time points. A mass-spectrometry-based proteomic approach was utilized to understand the involvement of probable candidate proteins toward developing a more severe, hemorrhagic form of dengue fever. Dengue-infected hospital-admitted patients with <5 days of fever were included in this study. Patient samples from the acute phase were screened for the presence of NS1 antigen using ELISA and subjected to molecular serotyping. Dengue molecular serotype-confirmed patient samples, pairwise from acute and critical phases with healthy control were subjected to qualitative and quantitative proteomic analysis, and then pathway analysis was performed. The protein-protein interaction network between the dengue virus and host proteins was depicted in the search for proteins associated with severe dengue pathophysiology. An array of apolipoprotein, cytokines, and endothelial proteins in association with virus replication and endothelial dysfunction were validated as biomolecules involved in severe dengue pathophysiology.

Integrated Approach to Severe Dengue Complicated by Guillain-Barré Syndrome and Multi-organ Failure.

This report details the case of a female patient who was admitted with severe dengue, which was further complicated by bilateral pneumonia and multiple organ involvement. The patient also developed quadriparesis, a neurological complication, and had a recent history of vaccination with the COVISHIELD COVID-19 vaccine. A nerve conduction study later determined the condition to be acute motor axonal neuropathy, a variant of Guillain-Barré syndrome (GBS). While neurological complications, such as GBS, are rare in dengue cases, they can significantly affect patient outcomes. Treatment with intravenous immunoglobulin (IVIG) has proven to be an effective disease-modifying therapy for GBS. IVIG therapy is recognized for its anti-inflammatory and immunomodulatory effects, making it beneficial in certain autoimmune conditions, including those involving the nervous system. However, its use in severe infections or sepsis remains controversial. In this case, IVIG therapy was administered alongside broad-spectrum antibiotics. The patient's favorable response to IVIG therapy and subsequent clinical improvement highlight the importance of early recognition and targeted intervention for neurological complications in dengue cases.

Complete Blood Count Values Over Time in Young Children During the Dengue Virus Epidemic in the Dominican Republic From 2018 to 2020.

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.

Risk of severe dengue during secondary infection: A population-based cohort study in Taiwan.

BACKGROUND: Dengue poses a significant public health concern. Secondary dengue infections with different dengue virus (DENV) serotypes have been linked to an increased risk of severe dengue. This study aimed to assess the risk of severe dengue during secondary infection in Taiwan. METHODS: A retrospective cohort study was conducted using Taiwan's National Health Insurance Research Database to identify dengue cases with secondary dengue infection born after 1944 from 2014 to 2015. Ten matched patients with primary infection were selected as controls using propensity score matching for each secondary dengue infection case. The odds ratio (OR) for severe dengue in secondary versus primary infections was calculated using conditional logistic regression. RESULTS: This study included 357 cases with secondary dengue infection and 3570 matched controls. The risk of severe dengue was found to be 7.8% in individuals with secondary infection, compared to 3.8% in those with primary dengue infection. Secondary infection significantly increased the risk of severe dengue (OR 2.13, 95% CI: 1.40-3.25, P = 0.0004). Notably, a significant association between secondary infection and severe dengue was observed only when the interval between the first and secondary infection was greater than two years (OR 3.19, 95% CI 2.04-5.00, P < 0.0001). CONCLUSION: Secondary dengue infection significantly increases the risk of severe disease in Taiwan, particularly when the interval between infections is over two years. Healthcare professionals should maintain heightened vigilance for individuals with a history of previous dengue infection, particularly if their initial diagnosis was more than two years prior.

Severe COVID-19 multisystem inflammatory syndrome versus severe dengue in children from Indonesia: a cross-sectional study.

INTRODUCTION: Severe multisystem inflammatory syndrome in children (MIS-C) and severe dengue are challenging to identify during the COVID-19 pandemic in dengue-endemic areas. Fever, multiorgan involvement, and shock characterize both severe MIS-C and severe dengue. Distinguishing between the two diseases is beneficial in initiating proper management. METHODS: Medical records of children < 18 years old who were hospitalized at Hasan Sadikin General Hospital's PICU between December 2020 and July 2022 with severe MIS-C or severe dengue were recorded. Differences were assessed using comparative and descriptive analyses. RESULTS: Seventeen severe dengue patients and 4 severe MIS-C were included. The average age of severe MIS-C was 11.5 years (SD ± 2.9, 95% CI), and that of severe dengue patients was 6.2 years (SD ± 4.4, 95% CI) (p value = 0.034, 95%). Fever and abdominal pain were the most common symptoms in both groups (p = 0.471, 95% CI). Rash (p = 0.049) and nonpurulent conjunctivitis (p = 0.035) were two symptoms with significant differences. The highest platelet count (p-value = 0.006, 95% CI), AST (p-value = 0.026, 95% CI), and D-dimer level (p-value = 0.025, 95% CI) were significantly different between the two cohorts. Cardiac abnormalities were found in all (100%) severe MIS-C patients, but only one (5.9%) in severe dengue patients. CONCLUSION: Age, rash, nonpurulent conjunctivitis, platelet count, AST and D-dimer level may distinguish severe MIS-C from severe dengue fever.

Utility of the WHO dengue guidelines in pediatric immunological studies.

Dengue is a significant health problem due to the high burden of critical infections during outbreaks. In 1997, the World Health Organization (WHO) classified dengue as dengue fever (DF), dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS). It was revised in 2009 (updated in 2015), and the new guidelines recommended classifying patients as dengue without warning signs (DNS), dengue with warning signs (DWS), and severe dengue (SD). Although the utility of the revised 2009 classification for clinical studies is accepted, for immunological studies it needs to be clarified. We determined the usefulness of the 2009 classification for pediatric studies that analyze the circulating interleukin (IL)-6 and IL-8, two inflammatory cytokines. Plasma levels of IL-6 and IL-8 were evaluated in the acute and convalescent phases by flow cytometry in children with dengue classified using the 1997 and 2009 WHO guidelines. The plasma levels of IL-6 and IL-8 were elevated during the acute and decreased during convalescence, and both cytokines served as a good marker of acute dengue illness compared to convalescence. There were no differences in the plasma level of the evaluated cytokines among children with different clinical severity with any classification, except for the IL-8, which was higher in DWS than DNS. Based on the levels of IL-8, the 2009 classification identified DWS plus SD (hospital-treated children) compared to the DNS group [area under the curve (AUC): 0.7, p = 0.028]. These results support the utility of the revised 2009 (updated in 2015) classification in studies of immune markers in pediatric dengue.

A Study on the Clinical Profile of Patients Presenting With Dengue Fever and the Precision Prediction of Dengue Severity Using Platelet Count at Presentation.

Background The most prevalent arbovirus infection in the world, dengue, has become a serious public health issue. This study aims to examine the clinical characteristics of individuals who present with dengue fever and use platelet count prediction to estimate the severity of dengue. Materials and methods This observational, cross-sectional study was conducted at Dr. D. Y. Patil Medical Hospital, Pune, Maharashtra, India, from February 2022 to May 2024. A total of 100 patients older than 12 years old who had dengue fever (presenting within three days of the first symptom) and were dengue NS1 antigen-positive in the laboratory were included. Patients under 12 years of age and pregnant women were excluded. Also excluded were patients with a history of prior dengue infection and patients on medications causing thrombocytopenia, such as antiplatelets (aspirin). Written informed consent was obtained from each patient. For adolescent boys and girls aged 13-18, consent was obtained from a parent or legal guardian along with the adolescent's assent. Data were collected through physical examinations and laboratory investigations. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 20 (Released 2011; IBM Corp., Armonk, New York), with descriptive statistics and tests for nonparametric data, setting the significance at p<0.05. Results The average age of the study participants was 29.48 ± 10.62 years, with 24% in the 0-20 year age group, 36% in the 21-30 age group, 24% in the 31-40 age group, 12% in the 41-50 age group, 3% in the 51-60 age group, and 1% in the 61-70 age group. Men comprised 65% of the population, with 35% being women. Weakness was the most prevalent symptom, followed by nausea and fever with chills. Patients with dengue fever without warning indications had a median platelet count of 114,000/µL upon admission; those with dengue fever with warning signs had a median count of 35,500/µL; and those with severe dengue had a median count of 25,000/µL. These distinctions attained statistical significance, underscored by p-values of <0.001. The predictive model for severe dengue using platelet count on presentation demonstrated a robust capacity to anticipate severe dengue with a noteworthy association (p<0.04), indicating an increased risk of severe dengue with a lower platelet count (<25,000/µL, odds ratio (OR) 7.5). Conclusion Dengue was more common in the young population, with a predominance of male patients. Weakness was the most common symptom. Patients with a platelet count less than 25,000/µL had 7.5 times more odds of developing severe dengue.

Kinetics of dengue viremia and its association with disease severity: an ambispective study.

Background: Dengue virus (DENV) infection is an important public health problem and causes significant morbidity and mortality. DENV typically causes a febrile illness that ranges from mild asymptomatic infection to fatal dengue hemorrhagic fever (DHF) and/or dengue shock syndrome (DSS). Early prediction of severe dengue disease is of utmost importance for providing prompt monitoring and treatment. The search for an ideal biomarker (host or viral factors) for early prediction of severe dengue remains elusive. Aim: To standardize a real time qRT-PCR for quantifying dengue viremia in serum samples and evaluate the kinetics of dengue viremia and its significance in disease severity. Results: In this ambispective study of 126 laboratory confirmed dengue patients, 72 were primary infections and 54 were secondary infections. The most common serotype was serotype 1 (n = 37) followed by serotype 2 (n = 34). According to WHO 1997 dengue case classification, 111 patients were cases of dengue fever (DF), 13 from DHF and 02 from DSS. Day 3 viremia levels were significantly elevated in severe dengue patients (DHF/DSS) as compared to that of DF (p < 0.05). However, no such association was found between viremia levels and serotype or immune status. Conclusion: Dengue viremia has a significant association with disease severity and day 3 viremia levels may be used as a predictor for dengue disease severity.

Comparison of predictive models using logistic regression, classification tree, and structural equation model for severe dengue.

BACKGROUND: The aim of this study was to compare the predictive performance of three statistical models-logistic regression, classification tree, and structural equation model (SEM)-in predicting severe dengue illness. METHODS/FINDINGS: We adopted modified classification of dengue illness severity based on WHO 1997 guideline. Predictive models were constructed using demographic factors and laboratory indicators on the day of fever occurrence. We developed statistical predictive models using data from two hospital cohorts in Thailand, consisting of 257 Thai children. Different predictive models for each category of severe dengue illness were developed employing logistic regression, classification tree, and SEM. The probability of discrimination of each model for severe output of disease was analyzed with external validation data sets from 55 and 700 patients not used in model development. From external validation using predictors on the day of presentation to the hospital, the area under the receiver operating characteristic curve was between 0.65 and 0.84 for the regression model. It was between 0.73 and 0.85 for SEM models. Classification tree models showed good results of sensitivity, ranging from 0.95 to 0.99. However, they showed poor specificity ranging from 0.10 to 0.44. CONCLUSIONS: Our study showed that SEM is comparable to logistic regression or classification tree, which was widely used for more severe form of dengue prediction.

Early-phase factors associated with pediatric severe dengue in the Thai-Myanmar cross-border region.

BACKGROUND: Dengue disease is caused by dengue virus, which is transmitted by Aedes mosquitoes in tropical and subtropical regions worldwide. Although most infected individuals have benign febrile illness or no apparent symptoms, a small percentage develop severe dengue, a potentially fatal condition that occurs after a febrile stage. Many studies have identified factors predicting dengue severity among different populations and time courses. To help find practical approaches applicable in remote settings, we focused on the investigation of early factors associated with severe dengue in Thai-Myanmar cross-border region. METHODS: This retrospective case-control study was performed to determine factors contributing to severe dengue in the pediatric population. We reviewed the hospital records of patients with dengue infection aged 0-19 years who were admitted to Maesot General Hospital, situated near the Thai-Myanmar cross-border region, between 2017 and 2022. Medical data during the first 5 days of illness and outcomes were collected and analyzed. RESULTS: This study included 144 patients with a serologically confirmed diagnosis of dengue infection, with 43 severe and 101 non-severe cases. Among biological factors, being an infant and belonging to an ethnic group in Myanmar showed a significant association with severe dengue in the univariable analysis. Multivariable logistic regression revealed that the presence of mucosal bleeding (adjusted OR 5.39, 95% CI 1.06-27.52, P = 0.043), a change in hematocrit ≥ 10% (adjusted OR 3.68, 95% CI 1.15-11.74, P = 0.028), and serum albumin < 35 g/L (adjusted OR 8.10, 95% CI 2.55-25.72, P < 0.001) during the first 5 days of illness were significantly associated with developing severe dengue. CONCLUSIONS: This study supports the use of certain WHO warning signs and hematocrit change during febrile phase to predict pediatric severe dengue in low-resource settings. Potential factors such as very young age and ethnic groups warrant further exploration to identify risks contributing to severe dengue infection.

Pre-or co-SARS-CoV-2 Infections Significantly Increase Severe Dengue Virus Disease Criteria: Implications for Clinicians.

Few studies have investigated whether SARS-CoV-2 infections increase the incidence of dengue haemorrhagic fever/shock syndrome (DHF/DSS) and/or severe dengue (SD) in dengue virus (DENV)-infected patients. This study was performed on a site with high incidences of classical dengue, but relatively few DHF/DSS or SD cases as defined by the WHO 1997 or 2009 criteria, respectively. Clinical, haematological/biochemical, and viral diagnostic data were collected from febrile patients before, during, and after the COVID-19 epidemic to assess whether (a) DENV-infected patients with prior SARS-CoV-2 infections or (b) DENV-SARS-CoV-2-co-infected patients had increased incidences of SD/DHF/DSS using logistic regression and machine learning models. Higher numbers of DHF/DSS/SD occurred during the COVID-19 epidemic, particularly in males and 18-40-year-olds. Significantly increased symptoms in the DENV-SARS-CoV-2-co-infected cases were (a) haemoconcentration (p < 0.0009) and hypotension (p < 0.0005) (DHF/DSS and SD criteria), (b) thrombocytopenia and mucosal bleeding (DHF/DSS-criteria), (c) abdominal pain, persistent vomiting, mucosal bleeding, and thrombocytopenia (SD warning signs) and (d) dyspnoea, but without fluid accumulation. DENV-infected patients with prior SARS-CoV-2 infections had significantly increased incidences of thrombocytopenia (DHF/DSS-criteria) and/or abdominal pain and persistent vomiting and also thrombocytopenia (SD warning signs), but without significant haemoconcentration or hypotension. DENV-SARS-CoV-2 co-infections significantly increased the incidence of DHF/DSS/SD, while DENV-infected patients with prior SARS-CoV-2 infections displayed significantly increased incidences of thrombocytopenia (DHF/DSS-criteria) and three important SD warning signs, which are therefore very important for health workers/clinicians in assessing patients' DHF/DSS/SD risk factors and planning their optimal therapies.

Dengue viremia kinetics and effects on platelet count and clinical outcomes: An analysis of 2340 patients from Vietnam.

Background: Viremia is a critical factor in understanding the pathogenesis of dengue infection, but limited data exist on viremia kinetics. This study aimed to investigate the kinetics of viremia and its effects on subsequent platelet count, severe dengue, and plasma leakage. Methods: We pooled data from three studies conducted in Vietnam between 2000 and 2016, involving 2340 dengue patients with daily viremia measurements and platelet counts after symptom onset. Viremia kinetics were assessed using a random effects model that accounted for left-censored data. The effects of viremia on subsequent platelet count and clinical outcomes were examined using a landmark approach with a random effects model and logistic regression model with generalized estimating equations, respectively. The rate of viremia decline was derived from the model of viremia kinetics. Its effect on the clinical outcomes was assessed by logistic regression models. Results: Viremia levels rapidly decreased following symptom onset, with variations observed depending on the infecting serotype. DENV-1 exhibited the highest mean viremia levels during the first 5-6 days, while DENV-4 demonstrated the shortest clearance time. Higher viremia levels were associated with decreased subsequent platelet counts from day 6 onwards. Elevated viremia levels on each illness day increased the risk of developing severe dengue and plasma leakage. However, the effect size decreased with later illness days. A more rapid decline in viremia is associated with a reduced risk of the clinical outcomes. Conclusions: This study provides comprehensive insights into viremia kinetics and its effect on subsequent platelet count and clinical outcomes in dengue patients. Our findings underscore the importance of measuring viremia levels during the early febrile phase for dengue studies and support the use of viremia kinetics as outcome for phase-2 dengue therapeutic trials. Funding: Wellcome Trust and European Union Seventh Framework Programme.

[Takotsubo syndrome in dengue patient]. / Síndrome de Takotsubo en paciente con dengue.

Takotsubo syndrome, was described in Japan in 1990, it is a stress cardiomyopathy, predominantly in women, usually postmenopausal. Cardiac hypokinesia occurs, with involvement of multiple coronary territories. In intensive care unit (ICU), it is considered underdiagnosed. Manifestations of severe dengue fever include cardiovascular involvement, mainly arrhythmias and systolic dysfunction. A case of a 72-year-old man is presented, who was hospitalized in ICU for dengue fever, with plateletopenia (15000 cells/mm3) and dehydration. After fluid management the patient reported respiratory discomfort, auscultating crackling rales. A pulmonary ultrasound was made where bilateral B lines were found with B7 pattern compatible with interstitial syndrome and pulmonary edema. Basal hyperkinesia, medial and apical hypokinesia with an image consistent with apical ballooning were observed in the transthoracic echocardiogram. The electrocardiogram showed complete right bundle branch block. Chagas serology was negative and quantitative troponin I was increased. In the context of severe dengue, a Takotsubo syndrome was diagnosed. The patient evolved favorably. After discharge, a normalization of the cardiac function was stated in ultrasound images. The case is of clinical importance due to the low association of these two diseases and the need to screen for cardiac involvement in severe dengue.

El síndrome de Takotsubo, fue descripto en Japón en 1990, se trata de una miocardiopatía por estrés, predominante en mujeres, generalmente postmenopáusicas. Se produce una hipoquinesia cardiaca, con compromiso de múltiples territorios coronarios. En las unidades de terapia intensiva (UTI), se considera subdiagnosticada. En las manifestaciones del dengue grave, se encuentra el compromiso cardiovascular, principalmente arritmias y disfunción sistólica. Se presenta el caso de un hombre de 72 años, internado en UTI por dengue, con plaquetopenia (15000 células/mm3) y deshidratación. Luego de la administración de fluidos refirió disconfort respiratorio, auscultándose estertores pulmonares. Se realizó ecografía pulmonar donde se apreció líneas B bilaterales con patrón B7 compatible con síndrome intersticial y edema pulmonar. En el ecocardiograma transtorácico se objetivó hiperquinesia basal, hipoquinesia medial y apical con imagen compatible con balonamiento apical. En el electrocardiograma se evidenció bloqueo completo de rama derecha. La serología para Chagas fue negativa y la troponina I cuantitativa se detectó aumentada. Se diagnosticó síndrome de Takotsubo en el contexto de dengue grave. El paciente evolucionó favorablemente. Posterior al alta, se constató normalización de la motilidad cardíaca, en las imágenes ecográficas. El caso es de importancia clínica por la baja asociación de las dos enfermedades y la necesidad de pesquisar el compromiso cardíaco en el dengue grave.

Papaya Leaf Extract Elevates Platelet Levels in Individuals With Dengue Fever.

Dengue, an arboviral illness, is notorious for inducing thrombocytopenia, leading to bleeding and heightened mortality risk. Carica papaya leaf extract has shown efficacy in elevating platelet counts. A 35-year-old male presented with fever, fatigue, and body pain persisting for four days. Additionally, he complained of severe back pain, ocular discomfort, and brief episodes of nosebleeds. Testing revealed a positive NS1 antigen, prompting the initiation of intravenous normal saline, paracetamol, and papaya extract tablets. Despite initial platelet levels of 74,000, a subsequent decline to 30,650 was observed following another nosebleed. Subsequently, the patient's spouse administered freshly prepared papaya leaf extract orally three to four times daily, resulting in a platelet count of 120,320 on day 14. Timely recognition of declining platelet levels and the commencement of C. Papaya leaf extract contributed significantly to averting mortality risks.