Clinical Profiles and Factors Associated with Death in Adults with Dengue Admitted to Intensive Care Units, Minas Gerais, Brazil

Temporal trends of dengue cases and deaths from 2007 to 2020 in Belo Horizonte, Brazil

Dengue, a disease with multifactorial determinants, is linked to population susceptibility to circulating viruses and the extent of vector infestation. This study aimed to analyze the temporal trends of dengue cases and deaths in Belo Horizonte, Minas Gerais, Brazil, from 2007 to 2020. Data from the Notifiable Diseases Information System (Sinan) were utilized for the investigation. To assess the disease's progression over the study period and predict its future incidence, time series analyses were conducted using a generalized additive model (GAM) and a seasonal autoregressive integrated moving average (SARIMA) model. Over the study period, a total of 463,566 dengue cases and 125 deaths were reported. Notably, there was an increase in severe cases and deaths, marking hyperendemics characterized by simultaneous virus circulation (79.17% in 2016-50% in 2019). The generalized additive model revealed a non-linear pattern with epidemic peaks in 2010, 2013, 2016, and 2019, indicating an explosive pattern of dengue incidence. The SARIMA (3,1,1) (0,0,0)12 model was validated for each year (2015 to 2019). Comparing the actual and predicted numbers of dengue cases, the model demonstrated its effectiveness for predicting cases in the municipality. The rising number of dengue cases emphasizes the importance of vector surveillance and control. Enhanced models and predictions by local health services will aid in anticipating necessary control measures to combat future epidemics.

Risk factors associated with severe dengue in Latin America: A systematic review and meta-analysis

OBJECTIVE

Severe dengue is a significant health problem in Latin America, with children being the most affected. Understanding risk factors for severe dengue is crucial for enhancing patient care. Therefore, this study aims to systematically review the literature to identify the risk factors associated with severe dengue in Latin America through systematic review and meta-analysis.

METHODS

PubMed, SciELO, LILACS and EMBASE databases were used to search for eligible scientific articles for the review. The outcomes considered were symptoms of severe dengue, hospitalisation and death. The Joanna Briggs Institute Critical Appraisal Checklist was used to assess the quality of the studies. Data analysis was performed using STATA v 13.0 software. The degree of heterogeneity between studies was quantified using the I2 measure, and statistically significant results were defined as those with p values <0.05.

RESULTS

Of the 1876 articles screened, 47 articles were included in the systematic review and 45 articles were analysed through meta-analysis. Identified risk factors associated with severe dengue included secondary dengue infection, female sex, white or Caucasian ethnicity and specific signs and symptoms such as headache, myalgia and/or arthralgia, vomiting/nausea, abdominal pain or tenderness, diarrhoea, prostration, lethargy, fatigue or similar. For the death outcome, respiratory symptoms and age <18 years were identified as risk factors. On the other hand, in women, the diagnosis of positive tourniquet test, platelet count <100,000 per μL and symptoms of capillary fragility were associated with a lower probability of death. These data highlight the importance of early screening of patients, to identify possible haemorrhagic signs and reduce deaths from dengue. This study has limitations, including possible publication bias, heterogeneity of results and study design biases.

CONCLUSION

These findings are significant for shaping strategies, management approaches and identifying high-risk groups, which will help establish future guidelines.

Frequency, Markers and Costs of Secondary Bacterial Infection in Pediatric Dengue

BACKGROUND

Secondary bacterial infection (SBI) occurs in a proportion of individuals with dengue and results in longer hospitalization, higher mortality, and increased health-related costs. However, the frequency, risk factors and predictive biomarkers of this comorbidity in pediatric dengue is partially known.

METHODS

We conducted a retrospective multicenter study in a dengue hyperendemic region of Colombia, analyzing 1597 children from two pediatric cohorts. We included children with confirmed dengue (mild to severe disease) and evaluated the rate of SBI, their clinical characteristics, diagnostic predictors and attention costs. We also assessed the diagnostic performance of plasma interleukin (IL)-6 for detecting SBI in pediatric dengue.

RESULTS

The frequency of SBI in children with dengue with warning signs in cohorts 1 and 2 was 2.4% and 7.3%, respectively, and this rate reached 30.7% and 38.2% in children with severe disease. Staphylococcus aureus and Escherichia coli were the more frequent infectious agents. Increased total leukocytes and C-reactive protein levels, as well as high IL-6 at hospital admission, in children <48 months of age were early indications of SBI in dengue. Higher rates of organ dysfunction, the requirement of a longer hospitalization and a 2.3-fold increase in attention costs were observed in SBI.

CONCLUSIONS

An important proportion of children with dengue course with SBI and exhibit higher morbidity. Elevated leukocytes, C-reactive protein and IL-6 in young children are early markers of SBI. Physicians should identify children with dengue and risk factors for SBI, microbiologically confirm the bacterial infection, and rationally and timely provide antimicrobial therapy.

Routine blood parameters of dengue infected children and adults. A meta-analysis

The World Health Organization (WHO) has revised dengue case classification in 2009 to better reflect the severity of the disease. However, there was no comprehensive meta-analysis of pooled routine blood parameters according to the age or the categories of the 2009 WHO classification. This study aimed to meta-analyze the routine blood parameters of dengue infected children and adults. Electronic search was performed with eligible articles included for review. Meta-analysis was conducted for six blood parameters stratified into children, adults and all ages, which were further grouped into the three 2009 WHO case classifications (dengue without warning signs, DwoWS; dengue with warning signs, DwWS; severe dengue, SD), non-severe dengue (non-SD) and 'All' cases. A total of 55 articles were included in the meta-analysis. Fifteen studies were conducted in the children's age category, 31 studies in the adult category and nine studies in all ages. The four selected pooled blood parameters for children were white blood cell (WBC) (×103/L) with 5.11 (SD), 5.64 (DwWS), 5.52 (DwoWS) and 4.68 (Non-SD) hematocrit (HCT) (%) with 36.78 (SD), 40.70 (DwWS), 35.00 (DwoWS) and 29.78 (Non-SD) platelet (PLT) (×103/µL) with 78.66 (SD), 108.01 (DwWS), 153.47 (DwoWS) and 108.29 (non-SD); and aspartate aminotransferase (AST) (/µL) with 248.88 (SD), 170.83 (DwWS), 83.24 (DwoWS) and 102.99 (non-SD). For adult, WBC were 4.96 (SD), 6.44 (DwWS), 7.74 (DwoWS) and 3.61 (non-SD); HCT were 39.50 (SD), 39.00 (DwWS), 37.45 (DwoWS) and 41.68 (non-SD); PLT were 49.62 (SD), 96.60 (DwWS), 114.37 (DwoWS) and 71.13 (non-SD); and AST were 399.50 (SD), 141.01 (DwWS), 96.19 (DwoWS) and 118.13 (non-SD). These blood parameters could not differentiate between each dengue severity according to the WHO 2009 classification, SD, DwoWS, DwWS and non-SD, because the timing of blood drawing was not known and there was an overlapping confidence interval among the clinical classification. Hence, these pooled blood parameter values could not be used to guide clinicians in management and did not correlate with severity as in previous scientific literatures and guidelines.

The Emergence of Travel-related Infections in Critical Care Units

Several tropical or geographically confined infectious diseases may lead to organ failure requiring management in an intensive care unit (ICU), both in endemic low- and middle-income countries where ICU facilities are increasingly being developed and in (nonendemic) high-income countries through an increase in international travel and migration. The ICU physician must know which of these diseases may be encountered and how to recognize, differentiate, and treat them. The four historically most prevalent "tropical" diseases (malaria, enteric fever, dengue, and rickettsiosis) can present with single or multiple organ failure in a very similar manner, which makes differentiation based solely on clinical signs very difficult. Specific but frequently subtle symptoms should be considered and related to the travel history of the patient, the geographic distribution of these diseases, and the incubation period. In the future, ICU physicians may also be more frequently confronted with rare but frequently lethal diseases, such as Ebola and other viral hemorrhagic fevers, leptospirosis, and yellow fever. No one could have foreseen the worldwide 2019-up to now coronavirus disease 2019 (COVID-19) crisis caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which was initially spread by travel too. In addition, the actual pandemic due to SARS-CoV-2 reminds us of the actual and potential threat of (re)-emerging pathogens. If left untreated or when treated with a delay, many travel-related diseases remain an important cause of morbidity and even mortality, even when high-quality critical care is provided. Awareness and a high index of suspicion of these diseases is a key skill for the ICU physicians of today and tomorrow to develop.

A modified Sequential Organ Failure Assessment score for dengue: development, evaluation and proposal for use in clinical trials

Background

Dengue is a neglected tropical disease, for which no therapeutic agents have shown clinical efficacy to date. Clinical trials have used strikingly variable clinical endpoints, which hampers reproducibility and comparability of findings. We investigated a delta modified Sequential Organ Failure Assessment (delta mSOFA) score as a uniform composite clinical endpoint for use in clinical trials investigating therapeutics for moderate and severe dengue.

Methods

We developed a modified SOFA score for dengue, measured and evaluated its performance at baseline and 48 h after enrolment in a prospective observational cohort of 124 adults admitted to a tertiary referral hospital in Vietnam with dengue shock. The modified SOFA score included pulse pressure in the cardiovascular component. Binary logistic regression, cox proportional hazard and linear regression models were used to estimate association between mSOFA, delta mSOFA and clinical outcomes.

Results

The analysis included 124 adults with dengue shock. 29 (23.4%) patients required ICU admission for organ support or due to persistent haemodynamic instability: 9/124 (7.3%) required mechanical ventilation, 8/124 (6.5%) required vasopressors, 6/124 (4.8%) required haemofiltration and 5/124 (4.0%) patients died. In univariate analyses, higher baseline and delta (48 h) mSOFA score for dengue were associated with admission to ICU, requirement for organ support and mortality, duration of ICU and hospital admission and IV fluid use.

Conclusions

The baseline and delta mSOFA scores for dengue performed well to discriminate patients with dengue shock by clinical outcomes, including duration of ICU and hospital admission, requirement for organ support and death. We plan to use delta mSOFA as the primary endpoint in an upcoming host-directed therapeutic trial and investigate the performance of this score in other phenotypes of severe dengue in adults and children.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07705-8.

The Roles of C-X-C Motif Chemokine Ligand 10 (CXCL10) in Dengue

Early diagnosis of dengue is crucial to prevent the progression to severe dengue (SD) leading to mortality rate reduction. This study aimed to determine the role of the CXCL10 in dengue and its potential utilization as one of the biomarkers for the early diagnosis of dengue. A case-control study was conducted involving healthy subjects as control (n = 10) and 193 subjects as dengue cases. The cases were categorized into dengue without warning signs (DwoWS: n = 70; 34.5 %), dengue with warning signs (DWWS: n = 108; 23.2 %), and severe dengue (SD: n = 15; 7.4 %). The socio-demographic characteristics, clinical presentations, and laboratory parameters (platelet and hematocrit) were documented. Serum CXCL10 quantification was performed using an enzyme-linked immunosorbent assay (ELISA). The descriptive analysis and Pearson’s correlation test were used to analyze demographic data and the correlation between CXCL10, hematocrit, and platelet respectively. The difference in age (p = 0.02) and ethnicity (p = 0.02) were significant between cases and control. Males more frequently had SD in contrast to females (4:1). The frequent warning signs were abdominal pain (42.0 %), severe vomiting (38.3 %), bleeding tendency (15.0 %), and fluid accumulation (7.2 %). The increase in hematocrit (p = 0.039) and platelet reduction (p = 0.0005) were significant in SD. The mean of CXCL10 in control (134.85 ± 48.52 rg/mL) was significantly lower than in cases (545.22 ± 76.33 rg/mL, p = 0.0005). The CXCL10 is evident to be a potential biomarker in the early diagnosis of dengue.

Liver function in dengue and its correlation with disease severity: a retrospective cross-sectional observational study in a tertiary care center in Coastal India

Introduction

dengue, the most important arthropod- borne disease is transmitted to humans by mosquitos of the Aedes family. Liver dysfunction in dengue varies from mild injury with elevation of transaminases to severe hepatocyte injury. The aim of our study was to assess the prevalence of hepatic dysfunction in patients with dengue and to correlate between the severity of the disease with the extent of hepatic dysfunction.

Methods

retrospective cross-sectional observational study including 120 patients with confirmed dengue serology admitted in Medicine Department of Father Muller Medical College during November 2018-December 2019. Patient demographics, presenting symptoms, clinical signs, laboratory parameters such as complete blood count, serum glutamic-oxaloacetic transaminase (SGOT), serum glutamic-pyruvic transaminase (SGPT), alkaline Phosphatase (ALP), total and direct bilirubin; serum albumin and globulin levels were collected. Patients were categorized based on the modified WHO classification of 2009 into dengue with or without the warning signs and severe dengue. Comparison of multiple means across disease severity was performed using One Way-ANOVA with post hoc analysis using least significant difference. Pearson's correlation coefficient test was used to calculate the correlation between transaminases and platelet count. P-value <0.05 and CI 95% were considered in all analyses.

Results

serum glutamic-oxaloacetic transaminase was elevated in 66.7%, 78.6% and 91.7% patients of dengue without warning signs, warning signs and severe dengue respectively. Serum glutamic-pyruvic transaminase was elevated in 42.4%, 52.4% and 91.7% patients of dengue without warning signs, warning signs and severe dengue respectively. Patients with elevated SGOT (93.8%) and SGPT (81.2%) had a higher incidence of bleeding manifestations. Hypoalbuminemia (50.8%) and A: G ratio reversal (27.3%) was significantly more in severe dengue (p<0.0001). Serum glutamic-oxaloacetic transaminase and serum glutamic-pyruvic transaminase levels negatively correlated with platelet count (p<0.0001).

Conclusion

liver involvement in the form of elevated transaminases was found in 74.2% dengue patients. Serum glutamic-oxaloacetic transaminase and serum glutamic-pyruvic transaminase level increases with increase in dengue severity which is indicated by fall in platelet count as they are negatively correlated with each other. Liver damage is one of the common complications of dengue and transaminitis, hypoalbuminemia and reversal of A: G ratio should be used as biochemical markers in dengue patients to detect and monitor hepatic dysfunction.

Does dengue and COVID-19 co-infection have worse outcomes? A systematic review of current evidence

In dengue-endemic regions, the co-infection with SARS-CoV-2 and dengue is a significant health concern. Therefore, we performed a literature search for relevant papers in seven databases on 26 Spetember 2021. Out of 24 articles, the mortality rate and intensive care unit (ICU) admission were 19.1% and 7.8%, respectively. The mean hospital stay was 11.4 days. In addition, we identified two pregnancies with dengue and COVID-19 co-infection; one ended with premature rupture of membrane and intrauterine growth restriction fetus, while the other one ended with maternal mortality and intrauterine fetal death. COVID-19 and dengue co-infection had worse outcomes regarding mortality rates, ICU admission, and prolonged hospital stay. Thus, wise-decision management approaches should be adequately offered to these patients to enhance their outcomes. Establishing an early diagnosis might be the answer to reducing the estimated significant burden of these conditions.

Severe dengue in adults and children, Ouagadougou (Burkina Faso), West Africa, October 2015–January 2017

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Severe dengue was common in this sudy.

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In contrast to multiple prior studies, the risk of severe dengue was greater for patients with primary dengue compared to those with secondary infection.

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Additional risk factors for severe dengue included age, male sex, haemoglobin S, diabetes, and hypertension.  Case mapping showed that dengue cases were more concentrated  in sectors located in the centre of the city and close to the health centres.

Introduction

Although dengue is the most common arbovirus infection worldwide, studies of severe dengue in Africa are lacking, and risk factors for severe dengue have been insufficiently described. This study was conducted in the context of the 2016 dengue epidemic in Burkina Faso to determine the prevalence of severe dengue, identify factors associated with severe dengue, and perform mapping of dengue cases in the country's capital, Ouagadougou.

Methods

This cross-sectional study was conducted from November 2015 to January 2017. Data were collected in 15 public and private health centres, and included sociodemographic, clinical and patient outcome variables. Dengue was diagnosed using SD Bioline Dengue Duo rapid diagnostic tests. Data were analysed using Epi-Info Version 7. Logistic regression was used to identify predictors of severe dengue. P<0.05 was considered significant. Dengue case mapping was performed using Geographic Information System software (ArcGIS).

Results

Of the 811 patients who tested positive for dengue, 609 (75%) had early dengue (AgNS1 positive) and 272 (33.5%) had severe dengue. Patient age ranged from 1 to 83 years (median 30.5 years) and 393 (48.3%) were female. Renal failure (13.1%) and severe bleeding (10.6%) were the most common signs of severe dengue. Risk factors for severe dengue included age, male sex, haemoglobin S, diabetes, hypertension, and primary dengue. Dengue cases were more concentrated  in sectors located in the centre of the city and close to the health centres.

Conclusion

Dengue is increasingly common in Africa and factors associated with severity should be sought systematically as soon as a patient tests positive. Additional studies are needed to determine if the factors found to be associated with severity can be used to identify patients at risk for dengue-related complications, and to provide early and specialized management to reduce morbidity and mortality related to dengue in Africa.

Development of a bedside score to predict dengue severity

Background

In 2017, New Caledonia experienced an outbreak of severe dengue causing high hospital burden (4379 cases, 416 hospital admissions, 15 deaths). We decided to build a local operational model predictive of dengue severity, which was needed to ease the healthcare circuit.

Methods

We retrospectively analyzed clinical and biological parameters associated with severe dengue in the cohort of patients hospitalized at the Territorial Hospital between January and July 2017 with confirmed dengue, in order to elaborate a comprehensive patient’s score. Patients were compared in univariate and multivariate analyses. Predictive models for severity were built using a descending step-wise method.

Results

Out of 383 included patients, 130 (34%) developed severe dengue and 13 (3.4%) died. Major risk factors identified in univariate analysis were: age, comorbidities, presence of at least one alert sign, platelets count < 30 × 10⁹/L, prothrombin time < 60%, AST and/or ALT > 10 N, and previous dengue infection. Severity was not influenced by the infecting dengue serotype nor by previous Zika infection.

Two models to predict dengue severity were built according to sex. Best models for females and males had respectively a median Area Under the Curve = 0.80 and 0.88, a sensitivity = 84.5 and 84.5%, a specificity = 78.6 and 95.5%, a positive predictive value = 63.3 and 92.9%, a negative predictive value = 92.8 and 91.3%. Models were secondarily validated on 130 patients hospitalized for dengue in 2018.

Conclusion

We built robust and efficient models to calculate a bedside score able to predict dengue severity in our setting. We propose the spreadsheet for dengue severity score calculations to health practitioners facing dengue outbreaks of enhanced severity in order to improve patients’ medical management and hospitalization flow.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06146-z.

Incidence of Cardiac Manifestations in Children with Dengue Fever: A Cross-sectional Study

OBJECTIVE

The aim of our study was to explore the incidence of cardiac involvement in children with dengue infection admitted in a tertiary care hospital and to evaluate the features of cardiac involvement with the severity of dengue fever.

METHODS

This was a cross-sectional study conducted from September 2014 to August 2016. A total of 130 patients with confirmed dengue NS1 antigen or IgM antibody positivity between the ages of 1 month and 18 years were evaluated. On the third day of admission, blood samples for cardiac markers were collected, and electrocardiograms (ECG) and echocardiograms were performed for each patient.

RESULTS

Of the 130 dengue patients in the study, 60 (46.2%) were males and 70 (53.8%) were females (male to female ratio, 1:1.16). Cardiac involvement was present in 60 (46.2%) children and was more prominent in children with severe dengue (72.7%), followed by dengue with warning symptoms (53.8%) and dengue fever (28.6%). There was no significant correlation between cardiac involvement and primary/secondary dengue. Both ECG and echocardiography changes were significantly correlated with dengue severity, as opposed to cardiac markers.

CONCLUSIONS

Cardiac involvement was present in children with dengue. Evaluation with ECG, echocardiography, and cardiac markers such as creatine phosphokinase-myocardial band (CPK-MB) are required for the management of cardiac complications in children with dengue. Our study showed an association between cardiac involvement and the severity of dengue. Further studies should be framed, and follow-up of dengue patients with cardiac involvement is necessary for therapeutic management.

Dengue: A Minireview

Dengue, caused by infection of any of four dengue virus serotypes (DENV-1 to DENV-4), is a mosquito-borne disease of major public health concern associated with significant morbidity, mortality, and economic cost, particularly in developing countries. Dengue incidence has increased 30-fold in the last 50 years and over 50% of the world’s population, in more than 100 countries, live in areas at risk of DENV infection. We reviews DENV biology, epidemiology, transmission dynamics including circulating serotypes and genotypes, the immune response, the pathogenesis of the disease as well as updated diagnostic methods, treatments, vector control and vaccine developments.

A prospective 3 year study of clinical spectrum and outcome of dengue fever in ICU from a tertiary care hospital in North India

Background and Aims:

The incidence of specific complications and adverse outcomes in dengue patients needing admission to intensive care units (ICU) may be quite variable in different regions of India presumably because of different strains of dengue virus or due to re infection.

Methods:

Patients admitted with acute febrile illness (AFI) with either positive IgM antibody or NS1 antigen for dengue were enrolled. Data were collected for 3 years (2015-2017). A total of 313 patients with acute febrile illness were admitted in the study period (2252 total ICU admissions). A total of 137 (43.76%) cases were serologically proven as dengue fever.

Results:

Median age (IQR) of study population was 36.0 (26.0–52.0) years. Liver (65.7%) was the main organ involved followed by acute kidney Injury (AKI) (18.6%). Dengue Shock Syndrome (DSS) was found in 18.6% of cases. Fifty-two patients died and the crude mortality was 38.0%. On multivariate analysis APACHE Score <10, thrombocytopenia, hepatic dysfunction, AKI and dengue shock syndrome (DSS) were associated with the risk of mortality.

Conclusion:

This study in ICU patients showed high mortality in relatively younger patients. Liver (in the form of raised Bilirubin) was the most common organ dysfunction. The need to recognise early warning signs for ICU admission is highlighted.

Clinical profiles and factors associated with mortality in adults with yellow fever admitted to an intensive care unit in Minas Gerais, Brazil

BACKGROUND

Yellow fever (YF) is a viral hemorrhagic disease caused by an arbovirus from the Flaviviridae family. Data on the clinical profile of severe YF in intensive care units (ICUs) are scarce. This study aimed to evaluate factors associated with YF mortality in patients admitted to a Brazilian ICU during the YF outbreaks of 2017 and 2018.

METHODS

This was a longitudinal cohort case series study that included YF patients admitted to the ICU. Demographics, clinical and laboratory data were analyzed. Cox regression identified independent predictors of death risk.

RESULTS

A total of 114 patients were studied. The median age was 48 years, and 92.1% were males. In univariate analysis, jaundice, leukopenia, bradycardia, prothrombin time, expressed as a ratio to the international normalized ratio-(PT-INR), alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin, lactate, arterial pH and bicarbonate, Acute Physiology and Chronic Health Evaluation II (APACHE II) and Simplified Acute Physiology Score 3 (SAPS 3) severity scores, transfusion of fresh frozen plasma, acute renal failure (Acute Kidney Injury Network stage III (AKIN III)), hemodialysis, cumulative fluid balance at 72 h of ICU, vasopressor use, seizures and grade IV encephalopathy were significantly associated with mortality. In multivariate analysis, factors independently associated with YF mortality were PT-INR, APACHE II, and grade IV hepatic encephalopathy.

CONCLUSIONS

In the large outbreak in Brazil, factors independently associated with death risk in YF were: PT-INR, APACHE II, and grade IV hepatic encephalopathy. Early identification of patients with YF mortality risk factors may be very useful. Once these patients with a poor prognosis have been identified, proper management should be promptly implemented.

Comorbidities increase in-hospital mortality in dengue patients in Brazil

Dengue remains an unmet public health burden. We determined risk factors for dengue in-hospital mortality in Brazil. Of 326,380 hospitalised dengue cases in 9-45-year-old individuals, there were 971 deaths. Risk of dying was 11-times higher in the presence of underlying common comorbidities (renal, infectious, pulmonary disease and diabetes), similar to the risk of dying from severe dengue and much higher with the combination. Ensuring access to integrated dengue preventative measures in individuals aged ≥ 9 years including those with comorbidities may help achieve the WHO objective of 50% reduction in mortality and 25% reduction in morbidity due to dengue by 2020.

Prediction of mortality in severe dengue cases

BACKGROUND

Increasing incidence of dengue cases in Malaysia over the last few years has been paralleled by increased deaths. Mortality prediction models will therefore be useful in clinical management. The aim of this study is to identify factors at diagnosis of severe dengue that predicts mortality and assess predictive models based on these identified factors.

METHOD

This is a retrospective cohort study of confirmed severe dengue patients that were admitted in 2014 to Hospital Kuala Lumpur. Data on baseline characteristics, clinical parameters, and laboratory findings at diagnosis of severe dengue were collected. The outcome of interest is death among patients diagnosed with severe dengue.

RESULTS

There were 199 patients with severe dengue included in the study. Multivariate analysis found lethargy, OR 3.84 (95% CI 1.23-12.03); bleeding, OR 8.88 (95% CI 2.91-27.15); pulse rate, OR 1.04 (95% CI 1.01-1.07); serum bicarbonate, OR 0.79 (95% CI 0.70-0.89) and serum lactate OR 1.27 (95% CI 1.09-1.47), to be statistically significant predictors of death. The regression equation to our model with the highest AUROC, 83.5 (95% CI 72.4-94.6), is: Log odds of death amongst severe dengue cases = - 1.021 - 0.220(Serum bicarbonate) + 0.001(ALT) + 0.067(Age) - 0.190(Gender).

CONCLUSION

This study showed that a large proportion of severe dengue occurred early, whilst patients were still febrile. The best prediction model to predict death at recognition of severe dengue is a model that incorporates serum bicarbonate and ALT levels.

Critical care for dengue in adult patients: an overview of current knowledge and future challenges

PURPOSE OF REVIEW

This review aims to update and summarize the current knowledge about clinical features, management, and risk factors of adult dengue patients requiring intensive care with consequently higher risk of mortality.

RECENT FINDINGS

Increasingly, there are more adult dengue patients who require intensive care. This may be due to a shift in epidemiology of dengue infection from mainly a pediatric disease toward adult disease. In addition, multiorgan dysfunction was observed to be a key risk factor for ICU admission and mortality. This may be due to older adults having preexisting comorbidities that potentially predispose to have multiple severe organ impairment. Interventions remain largely supportive but also require more evidence-based trials and treatment protocols.

SUMMARY

These findings highlight the common clinical manifestations of adult dengue patients and the challenges of clinical management in ICU. Risk factors for prediction of adult dengue patients who require ICU are available, but they lack validation and consistent study design for meta-analysis in future. Early recognition of these risk factors, with close monitoring and prompt clinical management, remains critical to reduce mortality.

Clinical, laboratory and virological data from suspected ZIKV patients in an endemic arbovirus area

BACKGROUND

The emergence of Zika virus (ZIKV) presents new challenges to both clinicians and public health authorities. Overlapping clinical features between the diseases caused by ZIKV, dengue (DENV) and chikungunya (CHIKV) and the lack of validated serological assays for ZIKV make accurate diagnosis difficult. Brazilian authorities largely rely on clinical and epidemiological data for the epidemiological and clinical classifications of most ZIKV cases.

OBJECTIVE

To report the laboratory and clinical profiles of patients diagnosed with Zika fever based only on clinical and epidemiological data.

STUDY DESIGN

We analyzed 433 suspected cases of ZIKV identified by the attending physician based on proposed clinical criteria. The samples were also screened for ZIKV, DENV and CHIKV using PCR.

RESULTS

Of the 433 patients analyzed, 168 (38.8%) were laboratory-confirmed for arboviruses: 96 were positive for ZIKV, 67 were positive for DENV (56 for DENV-2, 9 for DENV-1, and 2 for DENV-4), four were positive for co-infection with ZIKV/DENV-2, and one was positive for CHIKV. The most common signs or symptoms in the patients with laboratory-confirmed ZIKV were rash (100%), arthralgia (77.1%), fever (74.0%), myalgia (74.0%) and non-purulent conjunctivitis (69.8%). In patients with laboratory-confirmed DENV infections, the most frequently observed symptoms were rash (100%), fever (79.1%), myalgia (74.6%), headache (73.1%) and arthralgia (70.1%). The measure of association between clinical manifestations and laboratory manifestations among patients with ZIKV and DENV detected a statistically significant difference only in abdominal pain (p=0.04), leukopenia (p=0.003), and thrombocytopenia (p=0.01).

CONCLUSION

Our data suggests that clinical and epidemiological criteria alone are not a good tool for ZIKV and DENV differentiation, and that laboratory diagnosis should be mandatory.

Cardio-haemodynamic assessment and venous lactate in severe dengue: Relationship with recurrent shock and respiratory distress

Background

Dengue can cause plasma leakage that may lead to dengue shock syndrome (DSS). In approximately 30% of DSS cases, recurrent episodes of shock occur. These patients have a higher risk of fluid overload, respiratory distress and poor outcomes. We investigated the association of echocardiographically-derived cardiac function and intravascular volume parameters plus lactate levels, with the outcomes of recurrent shock and respiratory distress in severe dengue.

Methods/Principle findings

We performed a prospective observational study in Paediatric and adult ICU, at the Hospital for Tropical Diseases (HTD), Ho Chi Minh City, Vietnam. Patients with dengue were enrolled within 12 hours of admission to paediatric or adult ICU. A haemodynamic assessment and portable echocardiograms were carried out daily for 5 days from enrolment and all interventions recorded.

102 patients were enrolled; 22 patients did not develop DSS, 48 had a single episode of shock and 32 had recurrent shock. Patients with recurrent shock had a higher enrolment pulse than those with 1 episode or no shock (median: 114 vs. 100 vs. 100 b/min, P = 0.002), significantly lower Stroke Volume Index (SVI), (median: 21.6 vs. 22.8 vs. 26.8mls/m², P<0.001) and higher lactate levels (4.2 vs. 2.9 vs. 2.2 mmol/l, P = 0.001). Higher SVI and worse left ventricular function (higher Left Myocardial Performance Index) on study days 3–5 was associated with the secondary endpoint of respiratory distress. There was an association between the total IV fluid administered during the ICU admission and respiratory distress (OR: 1.03, 95% CI 1.01–1.06, P = 0.001). Admission lactate levels predicted patients who subsequently developed recurrent shock (P = 0.004), and correlated positively with the total IV fluid volume received (rho: 0.323, P = 0.001) and also with admission ALT (rho: 0.764, P<0.001) and AST (rho: 0.773, P<0.001).

Conclusions/Significance

Echo-derived intravascular volume assessment and venous lactate levels can help identify dengue patients at high risk of recurrent shock and respiratory distress in ICU. These findings may serve to, not only assist in the management of DSS patients, but also these haemodynamic endpoints could be used in future dengue fluid intervention trials.

Dengue is a viral illness that can lead to severe and potentially fatal complications. The most common complication is fluid leakage from blood vessels, which can cause low blood pressure or dengue shock syndrome (DSS). The majority of patients recover with simple intravenous fluid replacement, however in approximately 30% of DSS cases, recurrent episodes of shock occur, and these patients have a higher risk of fluid overload, respiratory distress and death. We investigated whether using portable echocardiograms (Echo) in the intensive care unit (ICU) to assess cardiac function and intravascular volume parameters as well as blood lactate levels, can help identify these patients. We found patients who developed recurrent shock had higher heart rates and lower Stroke Volume Index (SVI), and higher lactate levels at enrolment than those with 1 episode or no shock. Higher SVI and worse cardiac function after 3 days in ICU was associated with respiratory distress. Admission lactate levels predicted patients who subsequently developed recurrent shock and correlated positively with the total IV fluid volume received. These results demonstrate that Echo-derived intravascular volume assessment and venous lactate levels can help identify dengue patients at high risk of poor outcomes in the ICU, and could assist in the management of severe dengue.

Clinical and laboratory factors associated with mortality in dengue

Dengue is endemic in more than 100 countries, giving rise to an increased number of deaths in the last five years in the South-East Asian region. We report our findings from a retrospective study of adults admitted with confirmed dengue at our institution. We studied the clinical and laboratory parameters associated with mortality in these patients. Of the 172 hospitalised patients studied, 156 (90.69 %) recovered while 16 (9.3%) died. Univariate analysis showed altered sensorium on presentation, lower haemoglobin and haematocrit levels, higher serum creatinine, higher serum transaminase and lower serum albumin levels to be significantly associated with mortality in dengue. Further, using stepwise multivariate logistic regression, altered sensorium ( P = 0.006) and hypoalbuminemia ( P = 0.013) were identified as independent predictors of mortality in dengue. Identification of these parameters early in the course of disease should prompt intensification of treatment in dengue cases.

A Cohort Study of Adult Patients with Severe Dengue in Taiwanese Intensive Care Units: The Elderly and APTT Prolongation Matter for Prognosis

Background

There was a large dengue outbreak in Taiwan in 2015, in which the ages of the affected individuals were higher than those in other countries. The aim of this study was to explore the characteristics and prognostic factors for adults with severe dengue in intensive care units (ICUs).

Methods

All adults admitted to ICUs with dengue virus infection (DENV) at a medical center from July 1, 2015 to December 31, 2015 were enrolled. DENV was diagnosed by the presence of serum NS1 antigen, IgM antibodies to dengue virus, or dengue virus RNA by real-time reverse transcriptase polymerase chain reaction. Demographic data, clinical features, and lab data were collected, and a multivariate Cox model was used to identify the predictive factors for in-hospital mortality.

Results

Seventy-five patients admitted to ICUs with laboratory-confirmed DENV were enrolled (mean age 72.3±9.3 years). The most common comorbidities included hypertension (72.0%), diabetes (43.7%), and chronic kidney disease (22.7%). The in-hospital case fatality rate (CFR) was 41.3%. The patients who died were predominantly female, had higher disease severity at ICU admission, shorter ICU/hospital stay, longer initial activated partial thromboplastin time (APTT), and higher initial serum aspartate transaminase levels. Cardiac arrest before ICU admission (hazard ratio [HR]: 6.26 [1.91–20.54]), prolonged APTT (>48 seconds; HR: 3.91 [1.69–9.07]), and the presence of acute kidney injury on admission (HR: 2.48 [1.07–5.74]), were independently associated with in-hospital fatality in the Cox multivariate analysis.

Conclusion

During the 2015 dengue outbreak in Taiwan, the patients with severe dengue in ICUs were characterized by old age, multiple comorbidities, and a high CFR. Organ failure (including cardiac failure, and renal failure) and coagulation disturbance (prolongation of initial APTT) were independent predictive factors for in-hospital fatality.

Severe forms of dengue fever (DF) are usually considered as a pediatric disease in southern Asia and are graded from dengue hemorrhagic fever (DHF) to dengue with shock syndrome (DSS). However, the age of affected individuals is increasing in Singapore, Thailand, Mainland China, Taiwan and many other countries. Limited data are available on the elderly with DF in intensive care units (ICUs). DF in the elderly is an emerging infectious disease and poses a new clinical challenge to physicians. We enrolled the patients with laboratory-confirmed dengue in our ICU during the 2015 dengue outbreak in Taiwan. These patients were characterized by old age, multiple comorbidities, and a high case fatality rate (CFR). All of the patients were classified as severe dengue, and the in-hospital CFR was 41.3%. Renal failure and cardiac arrest were associated with fatality. In addition to organ failure, initial prolonged activated partial thromboplastin time (APTT) in our study was consistent with an independent predictive factor for in-hospital fatality. Previous studies have also reported that prolongation of APTT is a clinical predictor of dengue virus infection (DENV) or DHF. Our results highlight that APTT prolongation may be a prognostic factor in critically ill adults with severe dengue.

Evaluation of the importance of fever with respect to dengue prognosis according to the 2009 WHO classification: a retrospective study

Background

The 2009 revised World Health Organization (WHO) guidelines for dengue describe fever as the core symptom. Accordingly, the diagnosis of non-febrile patients is complicated. The aim of this study was to evaluate the importance of fever in patients with dengue according to the 2009 revised WHO classification.

Methods

In this study, we assessed 30,670 dengue cases using enzyme-linked immunosorbent assay, detection of the non-structural protein 1, or polymerase chain reaction for diagnostic confirmation. Fisher’s exact test was used to evaluate associations between fever and related clinical manifestations. The Mann–Whitney U test was used to assess the association of dengue classification with fever and time to treatment. The effects of fever and time to treatment on the risk of progression were analyzed using an ordinal logistic regression to stereotype the model.

Results

Disease classification was found to associate significantly with both fever and time to treatment (both P < 0.001). Non-febrile patients were nearly four-fold more likely to exhibit “dengue without warning signs” than “severe dengue” (odds ratio [OR] = 3.74; 95% confidence interval [CI]: 3.20–4.36). Patients who received treatment within 7 days were twice as likely to have “dengue without warning signs” as opposed to “severe dengue” when compared to those who waited >7 days (OR = 2.23; 95% CI: 1.78–2.80). However, this difference was negligible in the multivariate analysis (OR = 1.02; 95% CI: 0.98–1.07).

Conclusions

Fever is a risk factor for disease progression in patients with dengue. However, non-febrile patients should not be neglected because this may delay treatment and could lead to more severe disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-2128-4) contains supplementary material, which is available to authorized users.

Molecular surveillance of dengue in Minas Gerais provides insights on dengue virus 1 and 4 circulation in Brazil

Dengue, caused by any of the four types of Dengue virus (DENV) is the most important arbovirus in the world. In this study we performed a molecular surveillance of dengue during the greatest dengue outbreak that took place in Divinópolis, Minas Gerais state, Southeast Brazil, in 2013. Samples from 100 patients with clinical symptoms of dengue were studied and 26 were positive. The capsid/premembrane (CprM) and envelope gene sequences of some samples were amplified and sequenced. Molecular analyses demonstrated that two DENV-1 lineages, belonging to genotype V were introduced and co-circulated in Divinópolis. When compared to each other, those lineages presented high genetic diversity and showed unique amino acids substitutions in the envelope protein, including in domains I, II, and III. DENV-4 strains from Divinópolis clustered within genotype IIb and the most recent common ancestor was probably introduced into the city three years before the 2013 epidemic. Here we demonstrated for the first time the circulation of DENV-4 and the co-circulation of two DENV-1 lineages in Midwest region of Minas Gerais, Brazil. Moreover our analysis indicated the introduction of five DENV-1 lineages, genotype V into Brazil, in different times. J. Med. Virol. 89:966-973, 2017. © 2016 Wiley Periodicals, Inc.

Trend and geographic analysis of the prevalence of dengue in Taiwan, 2010-2015

BACKGROUND

Dengue is the most rapidly spreading disease caused by a mosquito-borne virus in the world. The incidence of dengue globally has increased 30-fold in the last 50 years. Understanding the prevalence of dengue and its longitudinal trends can improve prevention and control strategies. This study assessed the trends in prevalence of dengue in Taiwan by population characteristics and geographical region.

METHODS

Dengue and population data for the years 2010-2015 were obtained from the public statistics databases of the Taiwan Centers for Disease Control and Department of Statistics, Taiwan Ministry of Interior. Yearly prevalence rates of dengue were calculated by age group, sex, and administrative area within five geographic regions (northern, mid-western, southern, and eastern regions, and outer islands).

RESULTS

The national prevalence rate of dengue decreased gradually from 8 to 4 per 100000 population between 2010 and 2013, but it increased substantially in 2014 and 2015 to 67 and 187 per 100000 population, respectively. There was no significant difference in prevalence rate between males and females. People aged 60-69 years had a significantly higher prevalence rate than those in the other age groups during 2010-2014, and people aged over 70 years had the highest rate in 2015 (309 per 100000 population). The southern region had the highest yearly dengue prevalence rate (the rate decreased from 23 to 9 per 100000 population between 2010 and 2013, but increased to 220 and 616 per 100000 population in 2014 and 2015, respectively). Three unexpected outbreaks of dengue were observed during the study period: the first outbreak occurred in Penghu County in 2011 (prevalence rate 101 per 100000 population), the second in Kaohsiung City in 2014 (prevalence rate 540 per 100000 population), and the third in Tainan City in 2015 (prevalence rate 1208 per 100000 population).

CONCLUSIONS

More efforts are still needed to prevent and control dengue in Taiwan. The government should direct resources and interventions to southern Taiwan, which has a tropical climate and a high population density, and should target older people who are more likely to be infected. Strategies are also needed to respond quickly to unexpected incidents to prevent dengue outbreaks.

The exploration of risk factors of concurrent bacteraemia in patients critically ill with severe dengue

We investigated the clinical features of intensive care unit (ICU) patients with concomitant severe dengue infection and bacteraemia to identify risk factors for this comorbidity. The records of all ICU dengue patients admitted during the period of 31 July–30 November 2015 were reviewed. Patients with ‘concurrent bacteremia’ (positive bacterial blood culture within 72 h of ICU admission) were identified. ICU admission was required for 142 patients, of which 22 (15.5 %) had concurrent bacteraemia. Species of the genus Streptococcus was the most common pathogens, followed by Escherichia coli then species of the genus Staphylococcus. Patients with a severe dengue infection and bacteraemia had higher APACHE II and TISS scores, C-reactive protein (CRP) levels and leukocyte counts, positive fluid balances, longer activated partial thromboplastin times (APTTs), higher lactate levels and more kidney failure, but controls (severe dengue patients without bacteraemia) had higher Glasgow Coma Scale (GCS) scores, higher albumin levels and more abdominal pain (all P<0.05). Patients with bacteraemia had a higher mortality rate than did ontrols (40.9 vs 18.3 %; P=0.018). Multiple logistic regression analysis showed that bacteraemia was significantly positively associated with the following independent predictors: higher CRP levels [adjusted odds ratio (aOR): 1.026; 95 % confidence interval (CI): 1.008–1.044; P=0.005], and longer APTTs (aOR: 1.034; 95 CI: 1.004–1.065; P=0.027). Concurrent bacteraemia is not uncommon in severe dengue patients in the ICU, and it is associated with high mortality. Higher CRP levels and longer APTTs were two independent risk factors associated with bacteraemia.

Current management of severe dengue infection

INTRODUCTION

Traditionally a disease mainly affecting the pediatric population, dengue burden has increased significantly in recent decades and adults with severe disease may become more common. There is currently no effective anti-viral agent available for the treatment of dengue and supportive care is the mainstay of management. Areas covered: We present a review of current literature on dengue severity classification systems and the management of severe dengue in adults. In particular, emphasis was placed on organ impairment in dengue and management of elderly individuals with multiple medical problems. Expert commentary: There is an urgent need to search for an effective anti-viral agent to treat infected individuals. The commercial availability of a dengue vaccine in older children has provided optimism in reducing the disease burden but long term efficacy and safety are unknown. The results from phase III trials of two new candidate vaccines are eagerly awaited.

The outcomes of patients with severe dengue admitted to intensive care units

Outcomes of adult patients with dengue infections requiring intensive care unit (ICU) admissions remain unclear. We assessed the clinical manifestations and prognostic factors of patients critically ill with severe dengue.This retrospective study was done in a tertiary referral hospital with 96 adult ICU beds. All of the patients with laboratory-confirmed severe dengue infections and admitted to the ICU were enrolled between July 31 and November 31, 2015, during the large outbreak period. The medical records of all the recruited patients were reviewed for the following information: age, gender, clinical manifestations, disease severity scores, underlying conditions, laboratory examinations, and outcomes. The primary endpoint was to find the predictors of ICU mortality.During the study period, 4787 patients with dengue infections required ICU admission. One hundred forty-three (2.99%) were critically ill (mean age: 69.7 years). Hypertension (n = 90, 62.9%) and diabetes mellitus (n = 70, 49.0%) were the 2 most common underlying diseases. Eighty critically ill patients (55.9%) had cobacterial infections, and 33 had cobacteremia. The hematologic system failed most often, followed by thoracic and cardiovascular systems. Fever was the most common presentation (n = 112; 78.3%), followed by anorexia (n = 47; 32.9%) and abdominal pain (n = 46; 32.2%). Overall, 33 patients died (mortality rate: 23.1%). Multivariate analysis showed that ICU mortality was significantly associated with lower Glasgow Coma Scale (GCS) scores, lower platelet counts before ICU discharge, and more organ failures.The number of severe dengue patients who require ICU admission remains high. The mortality rate was associated with lower GCS scores, lower platelet counts, and more organ failures. In addition, more than half of the critically ill dengue patients had comorbid bacterial infections.

Bacterial coinfections in dengue virus disease: what we know and what is still obscure about an emerging concern

PURPOSE

Dengue virus is the most frequent arthropod-borne viral infection worldwide. Simultaneously to the growth of its incidence, cases of bacterial coinfection in dengue have been increasingly reported. The clinical course of dual infections may worsen for reciprocal interactions and delays in the diagnosis, so that clinicians should be aware of this eventuality. Therefore, we reviewed literature to provide an overview of the epidemiological, clinical, and physiopathological issues related to bacterial coinfections and bacteremia in dengue.

METHODS

Clinical studies and case reports regarding bacteremia and bacterial coinfections in dengue and the interactions between the pathogens published on PubMed were reviewed.

RESULTS

We found 26 case reports, only 3 studies on concurrent bacteremia and 12 studies reporting data on bacterial coinfections in dengue. According to the three available studies, the 0.18-7 % of dengue infections are accompanied by concurrent bacteremia, while the 14.3-44.4 % of dengue-related deaths seem associated to bacterial coinfections. Comorbidities, advanced age, and more severe dengue manifestations could be risk factors for dual infections. A longer duration of fever and alterations in laboratory parameters such as procalcitonin, hyponatremia, leukocyte count, and renal function tests can raise the suspicion.

CONCLUSIONS

Despite the real burden and consequences of this emerging concern is still not computable accurately due to the lack of a significant number of studies on large cohorts, clinicians need a greater awareness about it to early recognize warning signs, to properly use available diagnostic tools and to readily start antibiotic treatment able to prevent worsening in mortality and morbidity.

Patterns and causes of liver involvement in acute dengue infection

Background

Liver involvement in acute dengue infection is frequently observed and sometimes leads to acute liver failure, with fatal outcomes. Many factors are thought to contribute to liver dysfunction, including hypoxic injury due to decreased perfusion, direct damage by the virus and immune mediated injury. In this study, we sought to identify the pattern in the change in liver enzymes throughout the illness and its association with the degree of viraemia, onset and extent of plasma leakage and inflammatory mediators.

Methods

Serial daily blood samples were obtained from 55 adult patients with acute dengue from the time of admission to discharge and the liver function tests, viral loads and cytokines were assessed. The onset and extent of fluid leakage was measured by daily ultrasound examinations and all clinical and laboratory features were serially recorded.

Results

Aspartate transaminase (AST), alanine transaminase (ALT) and gamma glutamyl transferase (GGT) levels were elevated in patients with dengue infection throughout the illness. The highest AST levels were seen on day 6 of illness and both AST and GGT levels were significantly higher in patients with severe dengue (SD), when compared to those with non-severe dengue (NSD) on day 5 and 6 of illness. Three patients with SD had AST and ALT values of >1000/IU in the absence of any fluid leakage or a rise in the haematocrit (≥20 %). The peak of the AST levels and the lowest serum albumin levels were seen 24 h before the maximum fluid leakage and 24 h after the peak in viraemia. Both serum IL-10 and IL-17 levels were elevated during early illness and were significantly higher in those with SD when compared to NSD.

Conclusion

Dengue associated liver injury appears to peak around day 6 and 7. Therefore, liver function tests done at earlier dates might not reflect the extent of liver involvement in acute infection. Since severe liver involvement can occur in the absence of fluid leakage, after the peak viraemia, and since it is associated with high IL-17 and IL-10 levels, possible immune mechanisms leading to hepatic damage should be investigated.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1656-2) contains supplementary material, which is available to authorized users.