Clinical Severity in Acute Dengue Associates with Increased Plasma Interleukin-10 Levels

Abstract

Background: Dengue viruses, comprising four distinct serotypes, represent the most significant arthropod-borne viral infections globally. As reported by Monath in 1994, these viruses are responsible for more than 260,000 cases of dengue hemorrhagic fever (DHF) and approximately 20,000 deaths annually [1]. Dengue infections can manifest in various clinical syndromes. These encompass an undifferentiated febrile illness, which is more commonly observed in children. Methods: In our study, a subset of participants was chosen from each of the three diagnostic categories: Dengue Hemorrhagic Fever (DHF), Dengue Fever (DF), and Other Febrile Illnesses (OFI) for immunoassay testing. Due to limitations in the volume of available plasma, it was not feasible to conduct all immune response assessments on the same patients’ samples. The selection of these subgroup populations was carried out without any knowledge of clinical data, except for their final diagnosis. For each selected subject, we included all accessible samples, which ranged from 2 to 6 samples per subject. To serve as healthy controls in the immunoassays, plasma samples obtained during the 6-month follow-up visit from study subjects who had experienced acute dengue virus infection were utilized (n = 25). Results: The study involved a total of 55 children who were categorized into three distinct diagnostic groups: 25 children with Dengue Hemorrhagic Fever (DHF), 20 children with Dengue Fever (DF), and 10 children with Other Febrile Illnesses (OFI). Among the 25 children with DHF, the severity was further classified into grades, with 18 children classified as having grade 1 DHF, 2 children with grade 2 DHF, and 5 children displaying grade 3 DHF. This classification allowed for a comprehensive assessment of disease severity within the DHF subgroup. Conclusion: Certainly, this study presented compelling evidence of elevated IL-10 levels in children suffering from dengue infection. These heightened IL-10 levels demonstrated a clear correlation with the severity of the disease, effectively distinguishing between Dengue Fever (DF) and Dengue Hemorrhagic Fever (DHF).