Dengue score as a diagnostic predictor for pleural effusion and/or ascites: external validation and clinical application

Aspartate Aminotransferase-to-Platelet Ratio Index (APRI) as a Novel Score in Early Detection of Complicated Dengue Fever

Introduction

The occurrence of dengue fever presents a considerable burden for public health care in developing countries. This study aims to validate APRI as predictor score for severity of dengue fever so that catastrophic events could be prevented, and early triage can save lives.

Methods

The retrospective cross-sectional study was done on dengue positive patients from August to November 2023. APRI score was calculated for every patient at the time of admission. The primary end-point was non-complicated disease (Simple dengue fever) vs complicated disease (dengue hemorrhagic fever and dengue shock syndrome). ROC curve was used to identify the role of APRI in prediction of dengue complication. Youden index was used to find the cut-off value of APRI along with sensitivity, specificity, positive and negative likelihood ratios. To further evaluate the role of APRI score, patients were divided into two groups, patients with APRI score greater and lesser than cut-off value. The qualitative variables among two groups were compared by chi-square testing. The predictors of complicated dengue were first determined by univariate regression analysis and then confirmed by multivariate regression analysis.

Results

The mean APRI score of 135 patients was 20.06 ± 6.31. AUC for APRI score was 0.93 (p < 0.0001) indicating that APRI score calculated at the time of admission is an excellent marker in determining the complicated dengue. The cut-off value for APRI score was 9.04 (sensitivity 84.91%, specificity 89.02%, p < 0.0001). The patients with APRI <9.04 mostly developed simple dengue fever (54.1%) vs DHF (4.4%) and DSS (1.5%), while patients with APRI >9.04 had more DHF (20.7%) and DSS (12.6%) vs simple dengue fever (6.7%). None of the patient died with APRI <9.04 while the mortality rate was 3.7% in patients with APRI >9.04.

Conclusion

The APRI score, calculated at the time of admission, is an excellent marker in determining the severe dengue.

Severity of Dengue Viral Infection Based on Clinical and Hematological Parameters among Pakistani Patients

The global burden of dengue infections has increased dramatically. Early diagnosis of dengue infection is critical to proper medical management to avoid further complications in patients. This study was geared to assess the severity of dengue infections based on clinical and hematological examinations. A cross-sectional study was conducted among febrile patients with dengue infection in a teaching hospital in Pakistan. Blood samples were investigated for dengue-specific antibodies (IgM and IgG) and the nonstructural 1 antigen. The clinical findings of each subject were noted to assess the severity of the infection. Tests for hematological parameters were performed. Of 130 patients with confirmed dengue infection, 23 had severe and 107 had nonsevere dengue. Patients with severe dengue experienced mucosal bleeding (71.4%), fluid accumulation (57.1%), shock (35.7%), and gastrointestinal bleeding (28.6%). The most significant hematological findings among severe and nonsevere patients with dengue infection were thrombocytopenia, leukopenia, and a raised hematocrit level (P < 0.001). Patients with severe dengue infection showed marked thrombocytopenia, with a mean platelet count of 49.96 × 109 platelets/L. The clinical presentation of patients with dengue infection along with hematological markers are the most important clues for the diagnosis of, prognosis of, and therapy for dengue infection. Thrombocytopenia, leukopenia, and raised hematocrit levels were the most significant hematological parameters when assessing the severity of dengue infection.

Evaluation of remote radiologist-interpreted point-of-care ultrasound for suspected dengue patients in a primary health care facility in Colombia

BACKGROUND

Early identification of plasma leakage may guide treatment decisions in dengue patients. This study evaluated the value of point-of-care ultrasound (POCUS) to detect plasma leakage and predict hospitalization or referral to a higher level of care in suspected dengue patients under routine conditions at a primary care facility in Colombia.

METHODS

We conducted a cohort study between April 2019 and March 2020 in a primary care hospital in Cali, Colombia. We prospectively included and followed 178 patients who were at least 2 years old with fever of less than 10 days and clinician-suspected dengue. A trained general practitioner performed a standardized POCUS protocol. Images were quality-rated and overread by an expert radiologist, and her results and those of the general practitioner were compared using the Kappa index. Logistic regression was used to identify factors associated with plasma leakage at enrollment and explore its prognostic value regarding hospital admission or referral to a higher level of care.

RESULTS

Half (49.6%) POCUS images were of suitable quality to be interpreted. The proportion of plasma leakage reported by the radiologist was 85.1% (95% CI: 78.6-90.2%) and 47.2% by the study physician (Kappa = 0.25, 95% CI: 0.15-0.35). The most frequent ultrasound findings were ascites (hepatorenal 87.2%, splenorenal 64%, or pelvic 21.8%) and gallbladder wall thickening (10.5%). Plasma leakage was higher in subjects with thrombocytopenia (aOR = 4, 95% CI: 1.3-12.1) and lower in patients 30-59 years old (aOR = 0.1, 95% CI: 0.0-0.4) than in those 18 years old or younger. POCUS evidence of plasma leakage (aOR = 8.2, 95% CI: 2.2-29.9), thrombocytopenia (aOR = 6.3, 95% CI: 2.4-16.0) and pulse pressure (aOR = 1.1, 95% CI: 1.07-1.2) were associated with hospital admission or referral to a higher level of care.

CONCLUSIONS

Ultrasound is useful to detect plasma leakage in primary care and, challenges remain to guarantee high-quality images and diagnostic accuracy, for which a standardized dengue POCUS protocol and training program is needed.

To study ultrasound and chest X-ray findings and their role in the diagnosis of dengue fever in children

Introduction

Dengue fever is a fatal viral illness affecting almost all age groups and is seen in almost all tropical countries. Ultrasonography (USG) can be a useful tool for the assessment and diagnosis of dengue fever.

Objectives

The study aimed to evaluate X-ray and ultrasound findings in children with dengue fever.

Material and Methods

This was a prospective and cross-sectional study that was carried out in a hospital in Mumbai for over one year. All relevant data were collected, validated, and analyzed statistically on the software Epi Info 7.

Results

Abnormal X-ray findings noticed were pleural effusion, pneumonia, and bilateral nodular opacities. Pleural effusion and respiratory complications were more common in severe dengue (P < 0.05). Out of the 37 patients on whom USG was done, 33 (89.18%) had abnormal and 4 (10.81%) had normal USG findings. Of the 17 patients with dengue who showed warning signs, 16 (89.9%) had abnormal USG findings. Plasma leakage in the form of ascites and effusion was commonly seen. One hundred percent of patients with severe dengue had abnormal USG findings. The abnormal USG findings were more commonly detected between 5-7 days and were more commonly associated with IgG + IgM-positive serology.

Conclusion

Ultrasonography is a good modality for the diagnosis and evaluation of dengue patients. Serial ultrasound should be done for the assessment and evaluation of said patients.

The aspartate aminotransferase/platelet count ratio index as a marker of dengue virus infection: Course of illness

BACKGROUND

The usefulness of laboratory tests in the decision-making process with regard to early identification of dengue virus infection has not been widely reported, particularly the aspartate aminotransferase (AST)/platelet count ratio index during a patient's days of illness. The aim of this study was to examine the pattern of the ratio index over the course of illness and identify whether it is a marker of dengue virus infection in dengue patients, as well as to assess the role of other laboratory tests.

METHODS

A chart review of 205 dengue patients was analyzed using available records of 845 laboratory results within different time intervals or exam dates during the course of illness. We used repeated measures mixed binary logistic regression analyses to model the dengue virus infection, defined as giving at least one positive antibody test (yes/no).

RESULTS

The high risk of dengue virus infection in dengue patients was found in the male gender (adjusted OR=4.316, 95% CI: 1.285-14.498, P=0.018), in patients with a high AST/platelet count ratio index (adjusted OR=1.438, 95% CI: 1.057-1.957, P=0.021), in patients with a low MCV level (adjusted OR=0.815, 95% CI: 0.679-0.978, P=0.028), and in patients with a low ALT level (adjusted OR=0.996, 95% CI: 0.993-0.999, P=0.010).

CONCLUSION

Laboratory markers, in particular the AST/platelet count ratio index, can be useful for clinicians to strengthen the decision-making process in primary care settings. Furthermore, our model revealed that low MCV and low ALT are predictors of the dengue virus infection, while being a male increases the risk of dengue virus infection. More studies are needed to evaluate the impact of the AST/platelet count ratio index on the severity of dengue fever infection during the onset of symptoms and course of treatment.

Diagnostic accuracy and predictive value in differentiating the severity of dengue infection

OBJECTIVE

To review the diagnostic test accuracy and predictive value of statistical models in differentiating the severity of dengue infection.

METHODS

Electronic searches were conducted in the Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, MEDLINE (complete), PubMed and Scopus. Eligible studies to be included in this review were cohort studies with participants confirmed by laboratory test for dengue infection and comparison among the different severity of dengue infection by using statistical models. The methodological quality of the paper was assessed by independent reviewers using QUADAS-2.

RESULTS

Twenty-six studies published from 1994 to 2017 were included. Most diagnostic models produced an accuracy of 75% to 80% except one with 86%. Two models predicting severe dengue according to the WHO 2009 classification have 86% accuracy. Both of these logistic regression models were applied during the first three days of illness, and their sensitivity and specificity were 91-100% and 79.3-86%, respectively. Another model which evaluated the 30-day mortality of dengue infection had an accuracy of 98.5%.

CONCLUSION

Although there are several potential predictive or diagnostic models for dengue infection, their limitations could affect their validity. It is recommended that these models be revalidated in other clinical settings and their methods be improved and standardised in future.

Characterization of clinical patterns of dengue patients using an unsupervised machine learning approach

Background

Despite the greater sensitivity of the new dengue clinical classification proposed by the World Health Organization (WHO) in 2009, there is a need for a better definition of warning signs and clinical progression of dengue cases. Classic statistical methods have been used to evaluate risk criteria in dengue patients, however they usually cannot access the complexity of dengue clinical profiles. We propose the use of machine learning as an alternative tool to identify the possible characteristics that could be used to develop a risk criterion for severity in dengue patients.

Method

In this study, we analyzed the clinical profiles of 523 confirmed dengue cases using self-organizing maps (SOM) and random forest algorithms to identify clusters of patients with similar patterns.

Results

We identified four natural clusters, two with features of dengue without warning signs or mild disease, one that comprises the severe dengue cases and high frequency of warning signs, and another with intermediate characteristics. Age appeared as the key variable for splitting the data into these four clusters although warning signs such as abdominal pain or tenderness, clinical fluid accumulation, mucosal bleeding, lethargy, restlessness, liver enlargement and increased hematocrit associated with a decrease in platelet counts should also be considered to evaluate severity in dengue patients.

Conclusions

These findings suggest that age must be the first characteristic to be considered in places where dengue is hyperendemic. Our results show that warning signs should be closely monitored, mainly in children. Further studies exploring these results in a longitudinal approach may help to understand the full spectrum of dengue clinical manifestations.

Evaluation of biochemical and haematological changes in dengue fever and dengue hemorrhagic fever in Sri Lankan children: a prospective follow up study

BACKGROUND

Series of biochemical and haematological changes occur during the course of dengue infection, which vary depending on the clinical disease. The patterns of change are not well documented and identifying these patterns in children with dengue infection would help to anticipate the progression to different clinical stages thus enabling effective management.

METHODS

A prospective follow up study was conducted during the period of July 2013 - April 2014 at Professorial Pediatric unit, Lady Ridgeway Hospital for Children, Colombo, Sri Lanka. Children (5-12 years) admitted within the first 84 h of fever, with a clinical diagnosis of dengue infection were recruited. Children who became positive for dengue IgM were included in the final analysis. Blood was collected on admission for complete blood count, Alanine aminotransferase, Aspartate aminotransferase, albumin, cholesterol and corrected calcium. These tests were repeated at 12 hourly intervals during the hospital stay.

RESULTS

Data of 130-subjects were analyzed (Dengue fever /Dengue hemorrhagic fever: 100/30). There was a significant difference in the pattern of white cell counts, platelets and haematocrit in the two clinical groups. Both transaminase rose initially in both dengue fever and dengue hemorrhagic fever and a steep rise were seen between 8th and 9th days in hemorrhagic fever. Both albumin and cholesterol decreased significantly at the time of entering into the critical phase. According to Receiver operating characteristic curve analysis, albumin level crossing 37.5g/L (sensitivity 86.7%, specificity 77.8%) and a 0.38 mmol/L reduction in cholesterol level (sensitivity 77.3%, specificity 71.9%) between day 3 and 4 were the best predictors of entering into critical phase. Calcium levels did not show any distinct pattern.

CONCLUSIONS

There is a clear difference in the pattern of change of both hematological and biochemical parameters in dengue fever and dengue hemorrhagic fever. Reduction in albumin and cholesterol levels seen between the completion of day 3 and day 4 were highly valid predictors of entering into critical phase in dengue hemorrhagic fever.