Early diagnosis and prognosis of severe dengue

Abstract

Dengue is considered as an emerging infectious disease with a wide expansion to more than 100 countries and territories in the world. Dengue has great social, economic and health impacts on endemic regions causing the disease burden to the community and becoming one of the most serious public health concerns. We described clinical and virological features of paediatric dengue cases in southern Vietnam in a large prospective cohort study. We used the new classification of WHO 2009 to include dengue shock syndrome, severe bleeding and organ failure in the category of severe dengue in data analysis. Of 7544 patients enrolled into the study with complete haemobiochemical results available, 2060 patients (27.3%) had laboratory- confirmed diagnosis of dengue. The number of cases with severe dengue, dengue requiring parenteral fluids and uncomplicated dengue was 117 (5.7%), 156 (7.6%) and 1787 (86.7%) respectively. Proportions of RT-PCR positivity in the groups of severe dengue, dengue requiring parenteral fluids and uncomplicated dengue was 115/117 (98.3%), 149/156 (95.5%) and 1690/1787 (94.6%) respectively. It is a challenge for attending physicians in the outpatient settings to recognize early dengue patients. A simple tool, called Early Dengue Classifier (EDC), including information of age, white blood cell and platelet counts can be used alone or in combination with the NS1 rapid test to make early diagnosis of dengue within 72 hours of onset illness. We demonstrate that the early diagnosis of dengue can be enhanced beyond the current standard of care using a simple evidence-based algorithm. A prognostic algorithm using vomiting, platelet count, aspartate aminotransferase and NS1 rapid test result, called Early Severe Dengue Identifier (ESDI), can predict severe complications. Though the positive predictive value of the ESDI was low as seen with common prognostic models for a rare outcome, the results should support patient management and clinical trials of specific therapies.