Cytokine levels as biomarkers for leptospirosis patients.

Inflammatory mediators were suggested to be biomarkers for prediction of disease severity. In this study, we investigated the levels of IL-6, IL-8, IL-10 and TNF-α in leptospirosis patients with mild or severe illnesses. Sera samples were divided into two groups. The OI group and NOI groups included sera from patients with and without organ involvement, respectively. Each group consisted of 20 pairs of sera. Twenty-five sera from healthy individuals were included as controls. Cytokine levels were compared. Although IL-6, IL-8 and IL-10 levels in acute sera from the OI group were significantly higher than NOI group, only IL-8 level was significantly higher in the OI group when cytokine levels in convalescent sera were compared. TNF-α, an inflammatory cytokine widely studied in leptospirosis was not significantly different between two groups of patients. Our data suggested that IL-6, IL-8 and IL-10 were involved in disease severity. However, time of specimen collection could affect the significant levels of cytokines especially as biomarkers for monitoring disease severity.