Assay of Proinflannatory Cytokines (IL-6, IFN γ, TNFα) and its Correlation with Disease Severity in Dengue Fever

Abstract

Introduction: Dengue fever is the most common mosquito borne viral illness in humans. Study was done to determine the serum levels of pro-inflammatory cytokines (IL-6, IF Ngamma and TNF alpha) in patients with dengue infection and to determine the correlation of level of cytokine with disease severity, platelet count and SGOT values. Material and methods: Preserved samples of patients with the clinical features compatible with dengue infection and NSI antigen positivity admitted during the month of May and June 2016 in Pushpagiri Institute of Medical science and Research Centre, Thiruvalla were analysed for levels of pro-inflammatory cytokines (IL-6, IFN gamma, and TNF alpha). Disease severity of Dengue patients was assessed from the clinical details obtained from medical records. Total samples used in this study were 80 of which 49 were patients with dengue fever,11 were patients with severe dengue,10 were patients with other febrile illness and 10 are from healthy individuals. Results: The levels of all three cytokines were found to be elevated in the infected groups (dengue and severe dengue) when compared to the control groups (healthy and nondengue). The level of interleukin 6 and TNF alpha were found to be significantly elevated (p value <0.05) in the severe form of dengue. However no statistically significant difference (p value <0.05) between the infected and control group was found in Interferon gamma although it showed an elevation in the infected group. It was observed that all the three cytokines showed a negative correlation with platelet count. Conclusions: IL6 and TNF alpha correlated with disease severity suggesting that these cytokines can be used as a marker to predict the severity of the disease. Thus, necessary treatments and precaution can be taken in advance. TNF alpha correlated with the degree of thrombocytopenia and IL6 correlated with level of SGOT.