Clinical and Laboratory Factors Associated with Severe Dengue: A Case-Control Study of Hospitalized Children

Demographic characteristics, clinical symptoms, biochemical markers and probability of occurrence of severe dengue: A multicenter hospital-based study in Bangladesh

Establishing reliable early warning models for severe dengue cases is a high priority to facilitate triage in dengue-endemic areas and optimal use of limited resources. However, few studies have identified the complex interactive relationship between potential risk factors and severe dengue. This research aimed to assess the potential risk factors and detect their high-order combinative effects on severe dengue. A structured questionnaire was used to collect detailed dengue outbreak data from eight representative hospitals in Dhaka, Bangladesh, in 2019. Logistic regression and machine learning models were used to examine the complex effects of demographic characteristics, clinical symptoms, and biochemical markers on severe dengue. A total of 1,090 dengue cases (158 severe and 932 non-severe) were included in this study. Dyspnoea (Odds Ratio [OR] = 2.87, 95% Confidence Interval [CI]: 1.72 to 4.77), plasma leakage (OR = 3.61, 95% CI: 2.12 to 6.15), and hemorrhage (OR = 2.33, 95% CI: 1.46 to 3.73) were positively and significantly associated with the occurrence of severe dengue. Classification and regression tree models showed that the probability of occurrence of severe dengue cases ranged from 7% (age >12.5 years without plasma leakage) to 92.9% (age ≤12.5 years with dyspnoea and plasma leakage). The random forest model indicated that age was the most important factor in predicting severe dengue, followed by education, plasma leakage, platelet, and dyspnoea. The research provides new evidence to identify key risk factors contributing to severe dengue cases, which could be beneficial to clinical doctors to identify and predict the severity of dengue early.

Successful Outpatient Management of Children at a Secondary Care Hospital in Pakistan in a Dengue Fever Epidemic and Their Clinical Outcomes

Background

There is limited published literature on the feasibility of WHO 2009 guidelines for the management of dengue fever (DF) in Pakistani children. This study aimed to assess the outcome of children with DF who received outpatient treatment according to these guidelines during a DF epidemic.

Method

This was a prospective cohort study conducted at Federal General Hospital, a secondary care hospital, Islamabad, Pakistan, from 1st August to 31st October 2019. Using WHO DF 2009 guidelines, children ≤13 years, diagnosed as confirmed DF (NS1 Ag +), were classified into the outpatient (DF) or the inpatient group (DF with warning signs or severe dengue (SD)). The inpatient group was admitted to the Pakistan Institute of Medical Sciences, a tertiary care hospital, and discharged on recovery. These children were followed for the primary outcome, i.e., recovery or hospitalization by day 14 of enrollment. Additionally, clinical and laboratory features (Hb, HCT, TLC, PLT, and ALT) of the patients in the outpatient who remained stable with those who progressed to inpatient care during follow-up were compared; also, time of recovery of blood counts was assessed.

Results

Of 93 children with DF, 87 (93.5%) received outpatient care at enrollment. Of these, 6 (7.8%) deteriorated by day 7 and were admitted to inpatient care. SD was present in 6/93 (6.4%) patients at presentation and were admitted. All children showed signs of recovery until day 14. Male gender (p=0.049), lower normal mean platelet (p=0.02), and high mean hematocrit (p=0.001) were associated with disease progression.

Conclusion

The majority of children with confirmed DF who received outpatient treatment according to WHO 2009 guidelines were successfully managed. Additionally, confirmed DF with warning signs or SD were admitted and recovered. Regular follow-ups according to the guidelines are pertinent. Thrombocytopenia and high HCT were associated with disease progression.

Clinical predictors of severe dengue: a systematic review and meta-analysis

Background

Severe dengue is a life-threatening complication; rapid identification of these cases, followed by adequate management is crucial to improve the clinical prognosis. Therefore, this study aimed to identify risk factors and predictors of severe dengue.

Methods

A literature search for studies reporting risk factors of severe dengue among individuals with dengue virus infection was conducted in PubMed, Scopus and Web of Science database from inception to December 31, 2020. Pooled odds ratios (ORs) for patients’ demographic characteristics, co-morbidities, and warning signs were estimated using an inverse variance heterogeneity model.

Results

We included 143 articles in the meta-analysis from a total of 13 090 articles retrieved from the literature search. The risk factors of severe dengue were: being a child [OR = 1.96; 95% confidence interval (CI): 1.22–3.13], secondary infection (OR = 3.23; 95% CI: 2.28–4.57), and patients with pre-existing diabetes (OR = 2.88; 95% CI: 1.72–4.81) and renal disease (OR = 4.54; 95% CI: 1.55–13.31). Warning signs strongly associated with severe disease were increased haematocrit with a concurrent decrease in platelet count (OR = 5.13; 95% CI: 1.61–16.34), abdominal pain (OR = 2.00; 95% CI: 1.49–2.68), lethargy (OR = 2.73; 95% CI: 1.05–7.10), vomiting (OR = 1.80; 95% CI: 1.43–2.26), hepatomegaly (OR = 5.92; 95% CI: 3.29–10.66), ascites (OR = 6.30; 95% CI: 3.75–10.60), pleural effusion (OR = 5.72; 95% CI: 3.24–10.10) and melena (OR = 4.05; 95% CI: 1.64–10.00).

Conclusions

Our meta-analysis identified children, secondary infection, diabetes and renal disease(s) as important predictors of severe dengue. Our finding also supports the predictive ability of the WHO warning signs to identify severe dengue. These findings are useful for clinicians to identify severe dengue for management and timely interventions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40249-021-00908-2.

Clinical signs and symptoms associated with WHO severe dengue classification: a systematic review and meta-analysis

The World Health Organization (WHO) introduced the new dengue classification in 2009. We aimed to assess the association of clinical signs and symptoms with WHO severe dengue classification in clinical practice. A systematic literature search was performed using the databases of PubMed, Embase, and Scopus between 2009 and 2018 according to PRISMA guideline. Meta-analysis was performed with the RevMan software. A random or fixed-effect model was applied to pool odds ratios and 95% confidence intervals of important signs and symptoms across studies. Thirty nine articles from 1790 records were included in this review. In our meta-analysis, signs and symptoms associated with higher risk of severe dengue were comorbidity, vomiting, persistent vomiting, abdominal pain or tenderness, pleural effusion, ascites, epistaxis, gum bleeding, GI bleeding, skin bleeding, lethargy or restlessness, hepatomegaly (>2 cm), increased HCT with decreased platelets, shock, dyspnea, impaired consciousness, thrombocytopenia, elevated AST and ALT, gall bladder wall thickening and secondary infection. This review shows new factors comorbidity, epistaxis, GI and skin bleeding, dyspnea, gall bladder wall thickening and secondary infection may be useful to refine the 2009 classification to triage severe dengue patients.

Pattern and Outcome of Dengue Fever in a Pediatric Tertiary Hospital: A Retrospective Report

Introduction

For Pakistan, dengue has been established as a public health problem. With superimposed factors such as poor socioeconomic conditions, limited public health awareness, poor hygiene, and sanitation conditions, the situation has become more severe and complications have become frequent. Almost 90% of all infections occur in children of age less than 18 years. This is a three-year retrospective report of dengue fever in Southern Pakistan.

Methods

In this retrospective analysis, all records of patients admitted to the National Institute of Child Health, Karachi, from May 1, 2016, till April 30, 2019, diagnosed with dengue fever were recruited. Their demographic, clinical, and biochemical records were assessed. The outcome was also recorded. Data were entered and analyzed using Statistical Package for Social Sciences (SPSS) for Windows version 20.0 (IBM Corp., Chicago).

Results

Among 93 cases of dengue fever, there were 71 (76.3%) male and 22 (23.7%) female children. Their mean age was 5.7 ± 3.07 years. The mean duration from onset of disease to hospitalization was 4.2 ± 2.1 days. The mean platelet count was 47391.30 ± 41370.61 x 10⁹/L. Fever (100%) and abdominal pain (35.5%) were common presentations. Bleeding episodes were seen in 31% of children, rash in 15%, disseminated intravascular coagulation in 3%, and 1% developed pleural effusion. There were no mortalities; 87 (93.5%) were discharged and six (6.5%) children left against medical advice.

Conclusion

Fever, abdominal pain, bleeding episodes, and rash were common presentations. Hematological, hepatological, neurological, and pleural complications were not uncommon. The outcome of the disease was adequate and there were no mortalities.

Factors predicting the severity of dengue in patients with warning signs in Rio de Janeiro, Brazil (1986–2012)

Background

Since 1981, >12 million cases of dengue have been reported in Brazil. Early prediction of severe dengue with no warning signs is crucial to avoid progression to severe dengue. Here we aimed to identify early markers of dengue severity and characterize dengue infection in patients in Rio de Janeiro.

Methods

We evaluated early severity markers, serotypes, infection status, number of days of illness and viral loads associated with dengue fever in patients from Rio de Janeiro, Brazil through an observational retrospective study (1986–2012). We compared dengue without warning signs and dengue with warning signs/severe dengue (DWWS/SD). Infection status was classified by enzyme-linked immunosorbent assay and viraemia was quantified by quantitative real-time reverse transcription polymerase chain reaction.

Results

The presence of DWWS/ SD was significantly associated with younger age; patients 13–19 y of age had a significantly greater chance of presenting warning signs. Dengue virus type 3 (DENV3) was more likely to induce DWWS/SD, which was more frequent on days 4–5 of illness.

Conclusions

DENV3, 4–5 d of illness and 13–19 y of age were early biomarkers of dengue severity. To our knowledge, this was the first study to analyse the characteristics of dengue severity in the state of Rio de Janeiro over 27 y of epidemics since the introduction of DENV.