Role of Pro-inflammatory IL-8 and Anti-inflammatory IL-10 Cytokines in Dengue Severity

Abstract

Introduction: During dengue infection, cytokine levels may increase as various cytokines are released from infected inflammatory cells. This study was conducted to measure the levels of cytokines IL-8 and IL-10 in dengue patients and correlate them with dengue severity. Material & Methods: A prospective study was conducted on febrile patients suspected of dengue fever, seeking medical care in our institute. 107 cases confirmed to have dengue fever (by NS1/ IgM ELISA) and 100 healthy individuals with age and sex matched, were included in the study. The clinical features of all patients were recorded, and cytokine levels of IL-8 and IL-10 were estimated by ELISA in the dengue patients and healthy controls. Results: Out of 400 febrile patients suspected of having dengue fever, 107 (26.75%) cases were confirmed cases, of which 56 (52.3%), 20 (18.7%), and 31 (29%) were positive for only NS1 antigen, only IgM antibody, and both NS1 and IgM, respectively. Depending on the severity of the disease, 9 (8.5%) cases were classified as severe dengue cases while 98 (91.5%) as non-severe dengue fever. Mean levels (pg/ml) for IL-8 were 281.6 ± 76.6, 150.41 ± 55.9 and 75.4 ± 49.2 in severe dengue, dengue fever, and healthy controls respectively while for IL-10, the values were 219.4 ± 150.5, 38.9 ± 67.2, and 6.6 ± 0.65 among severe dengue cases, dengue cases, and healthy controls, respectively. Conclusion: Mean level of cytokines IL-8 and IL-10 were significantly raised in severe dengue patients as compared to non-severe dengue patients and healthy controls, suggesting their role in causing severe disease and as a potential predictor for disease severity and fatal outcome.