Inflammatory mediators in dengue virus infection in children: Interleukin-6 and its relation to C-reactive protein and secretory phospholipase A2

To assess the potential role of interleukin-6 (IL-6) in the pathogenesis of dengue virus infection, levels of this cytokine were measured in children with dengue vir-us infection on admission to the hospital. As presumed surr ogate markers of IL-6. C-reactive protein (CRP) and secretory phospholipase A2 (sPLA2) were measured. Three groups were studied: 33 apparently healthy children as negative controls, I I children with bacterial infections as p ositive controls, and 186 children with serologically documented dengue vir us infection. One-hundred and fifteen patients had dengue fever (DF) and 71 had dengue hemorrhagic fever (DHF). Compared with healthy controls, dengue shock syndrome (DSS) patients had significantly higher levels of IL-6 on a dmission (P < 0.05), comparable with those in positive controls. Dengue pat ients with shock had significantly higher levels of IL-6 than normotensive patients (P < 0.001) and higher levels of IL-6 were associated with a highe r incidence of ascites. C-reactive protein concentrations in dengue patient s and in healthy children were not different, but lower than in children wi th bacterial infections (P = 0.008). Secretory phospholipase A2 levels were higher in dengue patients than in apparently healthy children (P <less tha n or equal to> 0.05) and similar to those in children with bacterial infect ion. Dengue shock syndrome patients had significantly higher sPLA2 concentr ations than normotensive patients (P = 0.02). These data indicate that IL-6 and sPLA2 may have a pathogenetic role only in the most severe forms of de ngue virus infection.